Publications by authors named "Kun Ren"

69 Publications

UPLC-Q-Exactive-MS analysis for hepatotoxicity components of Evodiae Fructus based on spectrum-toxicity relationship.

J Chromatogr B Analyt Technol Biomed Life Sci 2021 Jun 18;1176:122772. Epub 2021 May 18.

School of Traditional Chinese Medicine, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning 110016, China. Electronic address:

Evodiae Fructus (EF) is generally divided into three categories: small flower EF (SEF), medium flower EF (MEF) and big flower EF (BEF) in commodity circulation according to the size of the fruit. It is a well-known and frequently used herbal medicine for treating gastrointestinal disorder-related stomachache and headache, which has aroused wide attention for its hepatotoxicity. However, reports about hepatotoxicity is controversial and hepatotoxic components are inconclusive. The study aimed to explain the controversial hepatotoxicity of EF and screen the components associated with hepatotoxicity of EF based on the spectrum-toxicity relationship. UPLC fingerprints of 39 batches of EF collected from different regions were established. Combined with the results of L02 cell viability assays, the spectrum-toxicity relationship was investigated on the basic of orthogonal partial least squares (OPLS). The results of the research demonstrated that the toxicity of EF was obviously various among the different categories, in particularly, SEF was with less toxicity, MEF except for adulterants and BEF had mild toxicity and adulterants of MEF (A-MEF) produced more damage to L02 cell and no regions specificity in hepatotoxicity of EF. Thereinto, samples, the contents of which do not meet the requirements of Chinese Pharmacopoeia, were adulterants. It was worth noting that P11, P17, P20 and P25 were closely related to hepatotoxicity of EF and they were respectively identified as limonin (LIM), evodiamine (EVO), 1-methyl-2-nonyl-4(1H)-quinolone (MNQ), and 1-methyl-2-undecyl-4(1H)-quinolone (MUQ) by UPLC-Q-Exactive-MS. The hepatoprotection of P11 and hepatotoxicity of P17 were consistent with the results of spectrum-toxicity relationship. In summary, A-MEF was more toxic than other categories and SEF was less toxic than the others. It was noteworthy that EVO was the main hepatotoxic component of EF and LIM was the main hepatoprotective component of EF. The results provided worthy evidence for better utilization and development of EF.
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http://dx.doi.org/10.1016/j.jchromb.2021.122772DOI Listing
June 2021

Biochanin A Mitigates Atherosclerosis by Inhibiting Lipid Accumulation and Inflammatory Response.

Oxid Med Cell Longev 2020 11;2020:8965047. Epub 2020 Nov 11.

Department of Pathophysiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, 230032 Anhui, China.

Biochanin A (BCA), a dietary isoflavone extracted from red clover and cabbage, has been shown to antagonize hypertension and myocardial ischemia/reperfusion injury. However, very little is known about its role in atherogenesis. The aim of this study was to observe the effects of BCA on atherosclerosis and explore the underlying mechanisms. Our results showed that administration of BCA promoted reverse cholesterol transport (RCT), improved plasma lipid profile, and decreased serum proinflammatory cytokine levels and atherosclerotic lesion area in apoE mice fed a Western diet. In THP-1 macrophage-derived foam cells, treatment with BCA upregulated ATP-binding cassette (ABC) transporter A1 (ABCA1) and ABCG1 expression and facilitated subsequent cholesterol efflux and diminished intracellular cholesterol contents by activating the peroxisome proliferator-activated receptor (PPAR)/liver X receptor (LXR) and PPAR/heme oxygenase 1 (HO-1) pathways. BCA also activated these two signaling pathways to inhibit the secretion of proinflammatory cytokines. Taken together, these findings suggest that BCA is protective against atherosclerosis by inhibiting lipid accumulation and inflammatory response through the PPAR/LXR and PPAR/HO-1 pathways. BCA may be an attractive drug for the prevention and treatment of atherosclerotic cardiovascular disease.
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http://dx.doi.org/10.1155/2020/8965047DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8074550PMC
May 2021

[Sources and Fate of Nitrate in Groundwater in a Typical Karst Basin: Insights from Carbon, Nitrogen, and Oxygen Isotopes].

Huan Jing Ke Xue 2021 May;42(5):2268-2275

Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004, China.

Multiple isotopes (C, N, and O) and hydrochemical data were used to trace the sources and fate of nitrate in ground and surface waters of the Babu subterranean stream watershed in Guizhou Province. The origin of nitrate in the water samples was also quantitatively analyzed by the SIAR model. Approximately 38% of the groundwater samples were not drinkable because the nitrate exceeded the drinking water standard, thereby indicating that the groundwater was seriously polluted by nitrate. The ranges of N-NO, O-NO, and O-HO in groundwater were 2.30‰-30.33‰ (mean of 9.68‰), 2.65‰-13.73‰ (mean of 6.64‰), and -8.83‰﹣-7.37‰ (mean of -8.18‰), respectively. Based on the stable isotopic compositions (N-NO, O-NO, and O-HO), nitrification was the dominant process in the basin. The nitric acid produced by nitrification promoted the dissolution of carbonate rocks, thereby leading to a significantly negative correlation (<0.001) between the carbon isotope of dissolved inorganic carbon (C) and N-NO and indicating that C, combined with N-NO, is effective in exploring the fate of nitrate in karst groundwater. The nitrate in the ground and surface waters mainly originated from soil N, manure and sewage, and ammonium nitrogen fertilizer. The results of the SIAR model showed that the contributions of soil N, manure and sewage, and ammonium nitrogen fertilizer were 36.19%, 33.71%, and 30.10% in groundwater, respectively, and 39.15%, 36.08%, and 24.77% in surface water, respectively. Therefore, it would be more effective to reduce the nitrate recharge flux in groundwater by simultaneously removing nitrate and ammonium nitrogen during wastewater treatment and by adopting scientific fertilization technology in agricultural areas.
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http://dx.doi.org/10.13227/j.hjkx.202010028DOI Listing
May 2021

CTRP12 ameliorates atherosclerosis by promoting cholesterol efflux and inhibiting inflammatory response via the miR-155-5p/LXRα pathway.

Cell Death Dis 2021 03 10;12(3):254. Epub 2021 Mar 10.

Institute of Clinical Medicine, The Second Affiliated Hospital of Hainan Medical University, Haikou, 570100, Hainan, China.

C1q tumor necrosis factor-related protein 12 (CTRP12), a conserved paralog of adiponectin, is closely associated with cardiovascular disease. However, little is known about its role in atherogenesis. The aim of this study was to examine the influence of CTRP12 on atherosclerosis and explore the underlying mechanisms. Our results showed that lentivirus-mediated CTRP12 overexpression inhibited lipid accumulation and inflammatory response in lipid-laden macrophages. Mechanistically, CTRP12 decreased miR-155-5p levels and then increased its target gene liver X receptor α (LXRα) expression, which increased ATP binding cassette transporter A1 (ABCA1)- and ABCG1-dependent cholesterol efflux and promoted macrophage polarization to the M2 phenotype. Injection of lentiviral vector expressing CTRP12 decreased atherosclerotic lesion area, elevated plasma high-density lipoprotein cholesterol levels, promoted reverse cholesterol transport (RCT), and alleviated inflammatory response in apolipoprotein E-deficient (apoE) mice fed a Western diet. Similar to the findings of in vitro experiments, CTRP12 overexpression diminished miR-155-5p levels but increased LXRα, ABCA1, and ABCG1 expression in the aortas of apoE mice. Taken together, these results suggest that CTRP12 protects against atherosclerosis by enhancing RCT efficiency and mitigating vascular inflammation via the miR-155-5p/LXRα pathway. Stimulating CTRP12 production could be a novel approach for reducing atherosclerosis.
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http://dx.doi.org/10.1038/s41419-021-03544-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7947013PMC
March 2021

Position selective dielectric polarization enhancement in CNT based heterostructures for highly efficient microwave absorption.

Nanoscale 2021 Feb;13(4):2324-2332

School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, People's Republic of China.

Constructing carbon nanotube (CNT) based heterostructures has proven to be an effective way of improving the microwave absorption (MA) capability of these materials, regardless of whether the heterostructures are located on the inner or outer walls of the CNTs. However, the potential of the two sides of CNTs for constructing efficient MA heterostructures has not been compared, and the underlying mechanism behind this difference has not been determined. Therefore, CNT based heterostructures with Fe2O3 nanoparticles inside (Fe2O3-in-CNTs) and outside (Fe2O3-out-CNTs) of the CNTs were synthesized and characterized. The minimum reflection loss and maximum effective bandwidth of the Fe2O3-in-CNTs are -34.1 dB at 3.0 mm and 5.1 GHz at 2.6 mm, much better than those of the Fe2O3-out-CNTs. Stronger interfacial polarization at the inner surface of the CNTs than at the outer surface was confirmed using off-axis electron holography, which is regarded as the key factor that determines the excellent MA performance of the heterointerface constructed by the inner surface of the CNTs. The attractive potential of the inner surface of CNTs for constructing highly efficient MA heterostructures has, to our knowledge, not been proposed before, the findings of which can shed the light on the approach of developing CNT composited MA materials that have outstanding MA properties.
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http://dx.doi.org/10.1039/d0nr08245gDOI Listing
February 2021

LncRNA kcnq1ot1 promotes lipid accumulation and accelerates atherosclerosis via functioning as a ceRNA through the miR-452-3p/HDAC3/ABCA1 axis.

Cell Death Dis 2020 12 9;11(12):1043. Epub 2020 Dec 9.

Institute of Clinical Medicine, The Second Affiliated Hospital of Hainan Medical University, Haikou, 570100, Hainan, PR China.

Kcnq1 overlapping transcript 1 (kcnq1ot1), an imprinted antisense lncRNA in the kcnq1 locus, acts as a potential contributor to cardiovascular disease, but its role in atherosclerosis remains unknown. The aim of this study was to explore the effects of kcnq1ot1 on atherogenesis and the underlying mechanism. Our results showed that kcnq1ot1 expression was significantly increased in mouse aorta with atherosclerosis and lipid-loaded macrophages. Lentivirus-mediated kcnq1ot1 overexpression markedly increased atherosclerotic plaque area and decreased plasma HDL-C levels and RCT efficiency in apoE mice fed a Western diet. Upregulation of kcnq1ot1 also reduced the expression of miR-452-3p and ABCA1 but increased HDAC3 levels in mouse aorta and THP-1 macrophages. Accordingly, kcnq1ot1 overexpression inhibited cholesterol efflux and promoted lipid accumulation in THP-1 macrophages. In contrast, kcnq1ot1 knockdown protected against atherosclerosis in apoE mice and suppressed lipid accumulation in THP-1 macrophages. Mechanistically, kcnq1ot1 enhanced HDAC3 expression by competitively binding to miR-452-3p, thereby inhibiting ABCA1 expression and subsequent cholesterol efflux. Taken together, these findings suggest that kcnq1ot1 promotes macrophage lipid accumulation and accelerates the development of atherosclerosis through the miR-452-3p/HDAC3/ABCA1 pathway.
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http://dx.doi.org/10.1038/s41419-020-03263-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7723992PMC
December 2020

Impacts of acid mine drainage on karst aquifers: Evidence from hydrogeochemistry, stable sulfur and oxygen isotopes.

Sci Total Environ 2021 Mar 24;761:143223. Epub 2020 Oct 24.

Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004, China. Electronic address:

The pollution of karst aquifers by acid mine drainage (AMD) waters is increasing. Major and minor ions (Ca, Mg, HCO, SO, F, and Fe), stable sulfur and oxygen isotopes of dissolved sulfates (δS and δO) and oxygen isotope of water (δO), were analyzed in rainwater, surface water, groundwater, and AMD water sampled from the Babu subterranean stream watershed, in Southwest China. The principal aim of this study was to explore the impact of AMD waters on the evolution of karst aquifers. Based on hydrogeochemistry and stable isotopes (δO, δO and δS): (1) the chemistry of AMD waters was primarily controlled by pyrite oxidation, karst conduit water by AMD waters and mixing with calcite and dolomite dissolution, and spring water by atmospheric precipitation and carbonate dissolution; (2) contamination of the karst conduit water was mainly attributed to the input of AMD waters, resulting in a shift of δS towards more negative values (from 3.4‰ to -13.2‰); (3) the quality of karst conduit water changed from suitable to unsuitable for irrigation and drinking, particularly due to the increase in total Fe, SO, and F concentrations, reflecting the cumulative effect of AMD waters derived from tailings dumps; this influence was enhanced during rainstorm/drought and anthropogenic activities; and (4) the flow of contaminated groundwater through the conduit promoted the dissolution of carbonates, especially during the dry season due to the greater proportion of AMD in the groundwater. This released more CO to the atmosphere. We believe that analysis of stable isotopes (δO, δO, and δS), combined with hydrogeochemistry, is effective for exploring the impact of AMD on karst aquifers. Therefore, reasonable treatment methods should be taken to reduce the negative impacts of tailings dumps on karst aquifers.
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http://dx.doi.org/10.1016/j.scitotenv.2020.143223DOI Listing
March 2021

LncRNA-modulated autophagy in plaque cells: a new paradigm of gene regulation in atherosclerosis?

Aging (Albany NY) 2020 11 4;12(21):22335-22349. Epub 2020 Nov 4.

The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan City People’s Hospital, Qingyuan, Guangdong, China.

The development of atherosclerosis is accompanied by the functional deterioration of plaque cells, which leads to the escalation of endothelial inflammation, abnormal vascular smooth muscle cell phenotype switching and the accumulation of lipid-laden macrophages within vascular walls. Autophagy, a highly conserved homeostatic mechanism, is critical for the delivery of cytoplasmic substrates to lysosomes for degradation. Moderate levels of autophagy prevent atherosclerosis by safeguarding plaque cells against apoptosis, preventing inflammation, and limiting the lipid burden, whereas excessive autophagy exacerbates cell damage and inflammation and thereby accelerates the formation of atherosclerotic plaques. Increasing lines of evidence suggest that long noncoding RNAs can be either beneficial or detrimental to atherosclerosis development by regulating the autophagy level. This review summarizes the research progress related to 1) the significant role of autophagy in atherosclerosis and 2) the effects of the lncRNA-mediated modulation of autophagy on the plaque cell fate, inflammation levels, proliferative capacity, and cholesterol metabolism and subsequently on atherogenesis.
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http://dx.doi.org/10.18632/aging.103786DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7695379PMC
November 2020

Quality assessment of Typhae Pollen Carbonisata based on chromaticity analysis combined with UPLC fingerprinting and thrombin activity.

Phytochem Anal 2020 Nov 8;31(6):809-817. Epub 2020 Jun 8.

School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, Liaoning, China.

Introduction: Typhae pollen (TP) has been used as an anticoagulant in traditional Chinese medicine and throughout Asia. Typhae Pollen Carbonisata (TPC), a processed product of TP, has hemostatic properties. TPC is produced by frying TP, and the degree of processing can be judged by the colour change from yellow to brown.

Objective: To establish a novel method for quality assessment of TPC and discriminate TPC from underdone products and overdone products.

Methodology: The Commission Internationale de l'Eclairage (CIE) L a b colour space values of TP and TPC were measured to establish the colour model of TPC. Ultra-performance liquid chromatography was developed for fingerprinting. Thrombin activity promoting rates, clotting time, and bleeding time illustrated the difference in the hemostatic effect of the processed products. Chemometric approaches were performed to reveal the correlation between components and colour values or thrombin activity.

Results: Reference ranges of colour values and mathematical functions of TPC were established. The developed method was found to be fast, economic, sensitive, and stable. Fingerprints and thrombin activity in conjunction with partial least squares (PLS) demonstrated that peaks 2, 4, 7, 30, and 36 (isorhamnetin) were the main contributors for colour values and hemostatic activity of TPC.

Conclusions: TPC and its unqualified products can be effectively distinguished based on chromaticity analysis, which provides a powerful tool for the comprehensive evaluation of the quality of Chinese herbal medicines.
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http://dx.doi.org/10.1002/pca.2947DOI Listing
November 2020

Trimetazidine attenuates diabetic inflammation via Nrf2 activation.

Int J Cardiol 2020 05;307:153

The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan City People's Hospital, Qingyuan, 511518, Guangdong, China. Electronic address:

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http://dx.doi.org/10.1016/j.ijcard.2019.10.003DOI Listing
May 2020

Crystal-Like Glassy Structure in Sc-Doped BiSbTe Ensuring Excellent Speed and Power Efficiency in Phase Change Memory.

ACS Appl Mater Interfaces 2020 Apr 25;12(14):16601-16608. Epub 2020 Mar 25.

State Key Laboratory of Functional Materials for Informatics, Laboratory of Nanotechnology, Shanghai Institute of Micro-System and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.

Phase change memory (PCM) is regarded as a promising technology for storage-class memory and neuromorphic computing, owing to the excellent performances in operation speed, data retention, endurance, and controllable crystallization dynamics, whereas the high power consumption of PCM remains to be a short-board characteristic that limits its extensive applications. Here, Sc-doped BiSbTe has been proposed for high-speed and low-power PCM applications. An operation speed of 6 ns and a threshold current of 0.7 mA have been achieved in 190 nm ScBiSbTe PCM, which consumes lower power than GeSbTe and ScSbTe PCM. A good endurance of 5 × 10 has been achieved, which is attributed to the small volume change of 4% during phase change and a good homogeneity phase in the crystalline state. The structure of amorphous ScBiSbTe has been characterized by experimental and theoretical methods, showing the existence of a large amount of crystal-like structural factions, which can efficiently minimize the atomic movements required for crystallization and subsequently improve the operation speed and power efficiency. The low diffusivity of Sc and Bi at room temperature and the rapidly increased diffusivity of Bi at elevated temperatures are fundamental for the high data retention of 94 °C and the fast crystallization in ScBiSbTe. The combination of high atomic mobility and minimized atomic movements during crystallization ensures the high speed and low power consumption of ScBiSbTe PCM, which can promote its application to energy-efficient systems, that is, AI chips and wearable electronics.
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http://dx.doi.org/10.1021/acsami.0c00476DOI Listing
April 2020

Transmission, refraction and dark-field retrieval in hard X-ray grating interferometry.

J Synchrotron Radiat 2020 Mar 26;27(Pt 2):494-502. Epub 2020 Feb 26.

National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui 230026, People's Republic of China.

A three-image algorithm is proposed to retrieve the sample's transmission, refraction and dark-field information in hard X-ray grating interferometry. Analytical formulae of the three-image algorithm are theoretically derived and presented, and evaluated by proof-of-principle synchrotron radiation experiments. The results confirm the feasibility of the proposed algorithm. The novelty of the proposed algorithm is that it allows versatile and tunable multimodal X-ray imaging by substantially relaxing the existing limitations on the lateral grating position. Furthermore, this algorithm can also be adapted for samples with negligible refraction, reducing the number of required sample measurements to two. Furthermore, the noise properties of the retrieved images are investigated in terms of the standard deviations. Theoretical models are presented and verified by synchrotron radiation measurements. It is shown that the noise standard deviations exhibit strong dependence on the lateral grating position, especially in the case of refraction and dark-field images. Further noise reduction and dose reduction can thus be possible by optimizing the lateral grating position for a selected region of interest. Those results can serve as general guidelines to optimize the data acquisition scheme for specific applications and problems.
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http://dx.doi.org/10.1107/S1600577519017223DOI Listing
March 2020

Vimentin promotes endothelial inflammation by activating NLRP3.

Int J Cardiol 2020 02;301:155

The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan City People's Hospital, Qingyuan, 511518, Guangdong, China. Electronic address:

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http://dx.doi.org/10.1016/j.ijcard.2019.09.024DOI Listing
February 2020

Statin ameliorates adipose inflammation via NLRP3 suppression.

Int J Cardiol 2020 02;301:154

The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan City People's Hospital, Qingyuan, 511518, Guangdong, China. Electronic address:

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http://dx.doi.org/10.1016/j.ijcard.2019.10.016DOI Listing
February 2020

Multiple Fano resonances with flexible tunablity based on symmetry-breaking resonators.

Beilstein J Nanotechnol 2019 11;10:2459-2467. Epub 2019 Dec 11.

College of Precision Instrument and Opto-electronics Engineering; Key Laboratory of Opto-electronics Information Technology, Ministry of Education, Tianjin 300072, China.

A symmetry-breaking nanostructure is proposed to achieve multiple Fano resonances. The nanostructure consists of an asymmetric ring resonator coupled to a plasmonic waveguide. The broken symmetry is introduced by deviating the centers of regular ring. New resonant modes that are not accessible through a regular symmetric ring cavity are excited. Thus, one asymmetric cavity can provide more than one resonant mode with the same mode order. As a result, the interval of Fano resonances is greatly reduced. By combining different rings with different degrees of asymmetry, multiple Fano resonances are generated. Those Fano resonances have different dependences on structural parameters due to their different physical origin. The resonance frequency and resonance peak number can be arbitrarily adjusted by changing the degree of asymmetry. This research may provide new opportunities to design on-chip optical devices with great tuning performance.
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http://dx.doi.org/10.3762/bjnano.10.236DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6941448PMC
December 2019

[Geochemical Characteristics and Ecological Significance of Carbon Isotopes in Groundwater Under the Influence of Different Land Use Types in Karst Areas].

Huan Jing Ke Xue 2019 Oct;40(10):4523-4531

Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004, China.

Based on the seasonal characteristics of groundwater hydrochemistry and the carbon isotopes (C) of dissolved inorganic carbon (DIC) in the Hongjiadu Basin, Guizhou Province, this paper discusses the natural processes and anthropogenic factors affecting the characteristics of C in karst groundwaters under different land use types. The results show that the main sources of DIC in groundwater are carbonate weathering and soil CO. In winter, the C values for groundwater ranged from -14.8‰ to -4.1‰ with an average of -10.1‰ and, in summer, ranged from -14.5‰ to -6.3‰ with an average of -10.2‰. Sulfuric acid from sulfide oxidation in coal-bearing strata and acid rain is involved in carbonate weathering, resulting in the enrichment of groundwater with heavy carbon isotopes. Due to the soil CO effect, the C values of woodland groundwater experiencing less disturbance from human activities are lower in summer than in winter. The degradation of organic matter input from residential areas is a significant contributor of DIC to groundwater. The average values of C in winter and summer were -11.9‰ and -11.6‰, respectively, and the seasonal difference was relatively small in residential areas. During different seasons and for different types of land use, human activities could lead to differences in groundwater C values and hydrochemistry. Therefore, C can reflect the impact of human activities on karst aquifers, which has important ecological significance.
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http://dx.doi.org/10.13227/j.hjkx.201904100DOI Listing
October 2019

Mineralogical phase separation and leaching characteristics of typical toxic elements in Chinese lignite fly ash.

Sci Total Environ 2020 Mar 20;708:135095. Epub 2019 Nov 20.

CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.

To investigate the distribution characteristics of typical toxic elements in different mineralogical phases of fly ash is of significance when fly ash is comprehensively utilized. In this study, lignite fly ash can be preliminarily separated into three mineralogical phases: unburned lignite, iron microbeads and aluminate-silicate microbeads by two methods namely screening and dry magnetic separation. Then, the aluminate-silicate microbeads were subjected to two-step leaching. The first step was to investigate whether toxic elements migrated easily in the environment by column leaching test. In the second step, the aluminate-silicate microbeads were stripped from the surface of the particles to the internal by the acid-base combined leaching method, then the structural characteristics of the product and the trend of toxic elements content were explored. The results showed that there were few toxic elements in unburned lignite and the toxic elements Cr, Ni, Mo and Cd had a relatively high proportion in the iron microbeads. Column leaching results showed that the toxic elements V, Cr, Mn, Co, Cu, Hg and Pb had higher leaching rates, which proved that these elements were significantly enriched on the surface of the particles and easily migrated in the environment. Cr, Mo, Cd and W were highly enriched in the quartz-mullite mixture. Mn, Co, Ni, Cu, Zn and As were highly enriched in the amorphous component. The toxic elements exhibited different leaching rules during the acid-base combined leaching process revealing the complex embedded relationship with constant elements.
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http://dx.doi.org/10.1016/j.scitotenv.2019.135095DOI Listing
March 2020

Relaxin inhibits macrophage inflammation by repressing NLRP3.

Int J Cardiol 2020 01;299:254

The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan City People's Hospital, Qingyuan 511518, Guangdong, China. Electronic address:

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http://dx.doi.org/10.1016/j.ijcard.2019.09.018DOI Listing
January 2020

Mangiferin promotes macrophage cholesterol efflux and protects against atherosclerosis by augmenting the expression of ABCA1 and ABCG1.

Aging (Albany NY) 2019 12 2;11(23):10992-11009. Epub 2019 Dec 2.

The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan City People's Hospital, Qingyuan, Guangdong, China.

Mangiferin has been identified as a potent cardioprotective factor that enhances high-density lipoprotein cholesterol levels in plasma. The aim of this study was to investigate the impact of mangiferin on macrophage cholesterol efflux and the development of atherosclerosis. The results showed that mangiferin injection significantly decreased atherosclerotic plaque size, and reduced plasma levels of low-density lipoprotein cholesterol, triglyceride, and total cholesterol in apoE knockout mice, whereas reverse cholesterol transport efficiency and high-density lipoprotein cholesterol levels were enhanced. study showed that mangiferin prevented lipid accumulation and promoted [H]-cholesterol efflux from acetylated LDL-loaded RAW264.7 macrophages with an increase in the expression of ATP binding cassette A1/G1 (ABCA1/G1), liver X receptor-α (LXRα) and peroxisome proliferator-activated receptor-γ (PPARγ). Moreover, transfection of PPARγ siRNA or LXRα siRNA markedly abolished the positive effects of mangiferin on ABCA1/G1 expression and cholesterol efflux. The opposite effects were observed after treatment with PPARγ agonist rosiglitazone or LXRα agonist T0901317. In conclusion, mangiferin may attenuate atherogenesis by promoting cholesterol efflux from macrophages via the PPARγ-LXRα-ABCA1/G1 pathway.
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http://dx.doi.org/10.18632/aging.102498DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6932905PMC
December 2019

Colchicine inhibits endothelial inflammation via NLRP3/CRP pathway.

Int J Cardiol 2019 11;294:55

Department of Histology and Embryology, Guilin Medical University, Guilin, Guangxi 541004, China. Electronic address:

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http://dx.doi.org/10.1016/j.ijcard.2019.06.070DOI Listing
November 2019

Contaminant sources and processes affecting spring water quality in a typical karst basin (Hongjiadu Basin, SW China): insights provided by hydrochemical and isotopic data.

Environ Sci Pollut Res Int 2019 Oct 31;26(30):31354-31367. Epub 2019 Aug 31.

Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, 541004, China.

Springs are an important source of drinking water supply in mountainous karst areas of SW China. However, the quality of many spring waters has deteriorated greatly in recent years, which leads to a significant problem of drinking water scarcity. In this study, hydrochemistry and stable sulfur and oxygen isotopic compositions of SO (δS and δO) of 38 representative samples of waters (incl. spring water, surface water, rainwater, and sewage) from the Hongjiadu Basin, Guizhou province, SW China, were investigated in order to identify the sources of contaminates in spring waters and trace the processes affecting the karst groundwater quality. Approximately 28% of the total investigated springs has been suffered from serious contamination and the concentrations of NO, SO, and total iron (TFe) in many spring waters have exceeded the standards for drinking water. The springs that have NO concentrations of > 30 mg/L are concentrated in residential and agricultural areas, suggesting that NO in spring water are mainly derived from chemical fertilizers, manure, and sewage. δS and δO data indicate that SO in spring water mainly originates from sulfide oxidation, acid rain, and sewage. Furthermore, the high δS and δO values of SO in some spring waters may be related to the occurrence of bacterial sulfate reduction. Some springs that are discharged from abandoned coal mines have SO concentrations of > 250 mg/L, demonstrating that mining activities have accelerated the deterioration of spring water quality. Also, springs with TFe concentrations of > 0.3 mg/L are discharged from coal-bearing strata, revealing that iron in spring waters is mainly derived from the oxidation of pyrite. Our results show that the karst spring waters are highly vulnerable to anthropogenic contaminations and human activities, such as agricultural fertilizing and sewage and waste disposal as well as mining activities, which exert a great impact on the quality of groundwater in karst areas.
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http://dx.doi.org/10.1007/s11356-019-06272-xDOI Listing
October 2019

Speeding Up the Write Operation for Multi-Level Cell Phase Change Memory with Programmable Ramp-Down Current Pulses.

Micromachines (Basel) 2019 Jul 8;10(7). Epub 2019 Jul 8.

State Key Laboratory of Functional Materials for Informatics; Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.

Multi-level cell (MLC) phase change memory (PCM) can not only effectively multiply the memory capacity while maintaining the cell area, but also has infinite potential in the application of the artificial neural network. The write and verify scheme is usually adopted to reduce the impact of device-to-device variability at the expense of a greater operation time and more power consumption. This paper proposes a novel write operation for multi-level cell phase change memory: Programmable ramp-down current pulses are utilized to program the RESET initialized memory cells to the expected resistance levels. In addition, a fully differential read circuit with an optional reference current source is employed to complete the readout operation. Eventually, a 2-bit/cell phase change memory chip is presented with a more efficient write operation of a single current pulse and a read access time of 65 ns. Some experiments are implemented to demonstrate the resistance distribution and the drift.
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http://dx.doi.org/10.3390/mi10070461DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6680789PMC
July 2019

Optimal design of high-power cascade co-pumping Er/Yb-codoped fiber lasers.

Opt Lett 2019 Mar;44(5):1100-1103

The Yb-ASE problem has been a main obstacle to the power scaling of Er/Yb-codoped fiber lasers (EYDFLs). In this Letter, cascade co-pumping high-power EYDFLs, i.e., EYDFLs with an Yb-band resonant cavity, are proposed and systematically analyzed, for the first time to the best of our knowledge. A high-Q Yb-band cavity is introduced in an EYDFL to lock and recycle the Yb band energy. The oscillation wavelength of the Yb cavity, the reflectivity of the output fiber grating, and the length of the fiber are optimized numerically. Thermal effects are also considered in the study. The simulation results show that compared to ordinary EYDFLs, the introduction of an appropriate Yb cavity can not only effectively suppress the Yb-ASE, increase the output power, and improve the pump conversion efficiency, but can also greatly shorten the optimal gain fiber length. Cascade co-pumping is a promising way to improve the performance of high-power EYDFLs.
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http://dx.doi.org/10.1364/OL.44.001100DOI Listing
March 2019

Sc-Centered Octahedron Enables High-Speed Phase Change Memory with Improved Data Retention and Reduced Power Consumption.

ACS Appl Mater Interfaces 2019 Mar 12;11(11):10848-10855. Epub 2019 Mar 12.

State Key Laboratory of Functional Materials for Informatics, Laboratory of Nanotechnology , Shanghai Institute of Micro-System and Information Technology, Chinese Academy of Sciences , Shanghai 200050 , China.

Phase change memory (PCM) with advantages of high operation speed, multilevel storage capability, spiking-time-dependent plasticity, etc., has wide application scenarios in both Von Neumann systems and neuromorphic systems. In the automotive application, intelligent system not only needs high efficiency to handle massive data processing but also good robustness to retain the existing data against high working temperature. In this work, Sc-doped GeTe is developed for PCM, which has achieved 120 °C data retention for 10 years, 6 ns operation speed, and 7 nJ low power consumption. The high data retention is attributed to the high coordination number of Sc and its strong bonds with Te atoms in the amorphous phase, which enhances the robustness of the atomic matrices. Sc-centered octahedrons in amorphous state provide a nucleation center, leading to fast crystallization. In the crystalline phase, Sc atoms occupy Ge vacancies to form a homogenous GeTe-like rhombohedral phase. The strong covalent-like Sc-Te bonds weaken the neighboring Ge-Te bonds, lowering energy for melting. Together with the increased energy efficiency originated from confined grain size, the reduced power consumption has been achieved. The improvements in data retention, speed, and power efficiency have made Sc-doped GeTe a promising candidate for high-performance automobile electronics application.
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http://dx.doi.org/10.1021/acsami.8b22580DOI Listing
March 2019

Magnetic-field sensor with self-reference characteristic based on a magnetic fluid and independent plasmonic dual resonances.

Beilstein J Nanotechnol 2019 22;10:247-255. Epub 2019 Jan 22.

College of Precision Instrument and Opto-electronics Engineering,Tianjin University; Key Laboratory of Opto-electronics Information Technology, Ministry of Education, Tianjin 300072, China.

A magnetic-field sensor with self-reference characteristic based on metal-dielectric-metal (MDM) plasmonic waveguides and a magnetic fluid (MF) is proposed and theoretically investigated. Independent dual resonances are supported by the coupled resonator-waveguide system. The physical mechanisms of dual resonances are analyzed by the temporal coupled-mode theory. The transmission response to an external magnetic field is explored by using the remarkable tunability of the refractive index of the MF. Based on the different dependence of two resonances on the external field, a magnetic-field sensor with self-reference characteristic is achieved. The magnetic-field nanosensor shows an excellent performance with a high sensitivity of 27 pm/Oe, i.e., 270 pm/mT. The proposed sensor takes advantage of the refractive-index tunability of the MF and the compactness of the MDM waveguide structure. This research may open new opportunities to design nanoscale magnetic sensors with good performance.
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http://dx.doi.org/10.3762/bjnano.10.23DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6350879PMC
January 2019

Technical Note: Single-shot phase retrieval method for synchrotron-based high-energy x-ray grating interferometry.

Med Phys 2019 Mar 13;46(3):1317-1322. Epub 2019 Feb 13.

National Synchrotron Radiation Laboratory University of Science and Technology of China, 230029, Hefei, China.

Purpose: X-ray grating interferometry (XGI) provides substantially increased contrast over conventional absorption-based imaging methods and therefore shows great potential for future biomedical applications. In this work, we propose a single-shot phase retrieval method for synchrotron-based high-energy x-ray grating interferometry. Contrary to existing retrieval methods, the presented novel approach enables direct retrieval of the object's phase map quantitatively from a single projection image, thus significantly simplifying the experimental procedure and reducing data acquisition times.

Methods: The phase retrieval method is analytically derived, based on the phase-attenuation duality of soft tissues when being imaged with high-energy x rays. The sensitivity of the retrieved phase map, quantified by the standard deviation, is evaluated as a function of the photon number. Numerical experiments are performed to validate the proposed method and provide some quantitative insight.

Results: The numerical results show that the method can provide high-quality phase images, where the well-known streak artifacts are significantly suppressed. Moreover, the retrieved phase maps confirm that the method is highly stable with respect to statistical noise.

Conclusions: Thanks to simplified experimental procedure and reduced acquisition time and dose deposition to the sample, we believe that this new method can find its potential in biomedical imaging and in vivo studies. Future work will focus on the adaptation of the method to polychromatic x ray from tube source and to computed tomography.
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http://dx.doi.org/10.1002/mp.13399DOI Listing
March 2019

Single-image phase retrieval for hard X-ray grating interferometry.

J Synchrotron Radiat 2019 Jan 1;26(Pt 1):215-219. Epub 2019 Jan 1.

National Synchrotron Radiation Laboratory, University of Science and Technology of China, Anhui 230026, People's Republic of China.

A single-image method is proposed for quantitative phase retrieval in hard X-ray grating interferometry. This novel method assumes a quasi-homogeneous sample, with a constant ratio between the real and imaginary parts of its complex refractive index. The method is first theoretically derived and presented, and then validated by synchrotron radiation experiments. Compared with the phase-stepping method, the presented approach abandons grating scanning and multiple image acquisition, and is therefore advantageous in terms of its simplified acquisition procedure and reduced data-collection times, which are especially important for applications such as in vivo imaging and phase tomography. Moreover, the sample's phase image, instead of its first derivative, is directly retrieved. In particular, the stripe artifacts encountered in the integrated phase images are significantly suppressed. The improved quality of the retrieved phase images can be beneficial for image interpretation and subsequent processing. Owing to its requirement for a single image and its robustness against noise, the present method is expected to find use in potential investigations in diverse applications.
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http://dx.doi.org/10.1107/S1600577518016727DOI Listing
January 2019

[Identification of Nitrate Pollution Sources Through Various Isotopic Methods: A Case Study of the Huixian Wetland].

Huan Jing Ke Xue 2018 Dec;39(12):5410-5417

Key Laboratory of Karst Dynamics Laboratory, Ministry of Land and Resources & Guangxi, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004, China.

In recent years, the ecological environment of wetlands has deteriorated under the predatory exploitation of human beings. Nitrate pollution is a major problem faced by wetland ecosystems. In this paper, Huixian karst wetland was selected as a study area to identify the main factors leading to the increase of nitrate in wetland water. The main sources of nitrate pollution in the area were determined by means of N(NO) and O(NO) isotopes. The contribution rate of all types of pollution sources was determined with the SIAR model. To explore the relationship between the spatial distribution of the nitrate concentration and the groundwater runoff conditions, the C isotopes were used to qualitatively characterize the runoff conditions of the groundwater. The results show that there are three main factors affecting the nitrate concentration in the study area:animal manure and domestic sewage, NO in chemical fertilizer, and soil nitrogen. The average contribution rates to nitrate pollution are 39.1%, 32.2%, and 28.5% respectively. The C isotope data clarify that a light C reflects better groundwater runoff conditions. The concentration of NO is generally lower, while the NO concentration corresponding to heavy C is generally higher. The condition of the groundwater runoff to a certain extent also affects the distribution of the NO concentration.
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http://dx.doi.org/10.13227/j.hjkx.201803212DOI Listing
December 2018

N-acetylcysteine decreases malignant characteristics of glioblastoma cells by inhibiting Notch2 signaling.

J Exp Clin Cancer Res 2019 Jan 3;38(1). Epub 2019 Jan 3.

School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.

Background: Glioblastomas multiforme (GBM) is the most devastating primary intracranial malignancy lacking effective clinical treatments. Notch2 has been established to be a prognostic marker and probably involved in GBM malignant progression. N-acetylcysteine (NAC), a precursor of intracellular glutathione (GSH), has been widely implicated in prevention and therapy of several cancers. However, the role of NAC in GBM remains unclear and the property of NAC independent of its antioxidation is largely unknown.

Methods: The mRNA and protein levels of Notch family and other related factors were detected by RT-PCR and western blot, respectively. In addition, intracellular reactive oxygen species (ROS) was measured by flow cytometry-based DCFH-DA. Moreover, cell viability was assessed by CCK8 and cell cycle was analyzed by flow cytometry-based PI staining. The level of apoptosis was checked by flow cytometry-based Annexin V/PI. Cell migration and invasion were evaluated by wound healing and transwell invasion assays. At last, U87 Xenograft model was established to confirm whether NAC could restrain the growth of tumor.

Results: Our data showed that NAC could decrease the protein level of Notch2. Meanwhile, NAC had a decreasing effect on the mRNA and protein levels of its downstream targets Hes1 and Hey1. These effects caused by NAC were independent of cellular GSH and ROS levels. The mechanism of NAC-mediated Notch2 reduction was elucidated by promoting Notch2 degradation through Itch-dependent lysosome pathway. Furthermore, NAC could prevent proliferation, migration, and invasion and might induce apoptosis in GBM cells via targeting Notch2. Significantly, NAC could suppress the growth of tumor in vivo.

Conclusions: NAC could facilitate Notch2 degradation through lysosomal pathway in an antioxidant-independent manner, thus attenuating Notch2 malignant signaling in GBM cells. The remarkable ability of NAC to inhibit cancer cell proliferation and tumor growth may implicate a novel application of NAC on GBM therapy.
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http://dx.doi.org/10.1186/s13046-018-1016-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6319015PMC
January 2019

S1P promotes inflammation-induced tube formation by HLECs via the S1PR1/NF-κB pathway.

Int Immunopharmacol 2019 Jan 23;66:224-235. Epub 2018 Nov 23.

Institute of Cardiovascular Disease, Key Laboratory for Atherosclerology of Hunan Province, University of South China, 28 W Changsheng Road, Hengyang, 421001, Hunan, China. Electronic address:

Inflammation-induced lymphangiogenesis is a widely accepted concept. However, most of the inflammatory factors and their related mechanisms have not been clarified. It has been reported that sphingosine-1-phosphate (S1P) is not only closely related to the chronic inflammatory process but also affects angiogenesis. Therefore, we investigated the inflammatory effects of S1P on human lymphatic endothelial cells (HLECs). Our results showed that S1P promotes tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) secretion in HLECs. We also confirmed that S1P-stimulated TNF-α and IL-1β secretion is mediated through S1P receptor 1 (S1PR1). Using TNF-α siRNA and IL-1β siRNA, we found that TNF-α and IL-1β play essential roles in S1P-induced HLEC proliferation, migration, and tube formation. S1P induces phosphorylation of NF-κB p65 and activation of NF-κB nuclear translocation. A S1PR1 antagonist (W146) and NF-κB inhibitor (BAY11-7082) inhibited S1P-induced TNF-α and IL-1β secretion and prevented NF-κB nuclear translocation. Taken together, the results demonstrated for the first time that S1P promotes the secretion of TNF-α and IL-1β in HLECs via S1PR1-mediated NF-κB signaling pathways, thus affecting lymphangiogenesis. The study provides a new strategy for finding treatments for lymphangiogenesis-related diseases.
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http://dx.doi.org/10.1016/j.intimp.2018.11.032DOI Listing
January 2019