Publications by authors named "Xiaojuan Zhao"

94 Publications

Digital Light Processing 4D Printing of Transparent, Strong, Highly Conductive Hydrogels.

ACS Appl Mater Interfaces 2021 Jul 20. Epub 2021 Jul 20.

Key Laboratory of Science and Technology on High-tech Polymer Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.

Hydrogels have excellent biocompatibility, transparency, stretchability, and ionic conductivity, but their fabrication through photopolymerization-based 3D printing is limited due to the low solubility of hydrophobic photoinitiators and lack of efficient hydrophilic photoinitiators. Herein, a type of microemulsion is synthesized and the common hydrophobic photoinitiator can be adopted and finally, a series of transparent hydrogels with high strength (up to 22.9 MPa), elasticity (up to 583%), and ionic conductivity (up to 9.64 S m) are fabricated through digital light processing 3D printing technology. Objects with complex structures and a high printing resolution are printed. Hydrogels with both high strength and high ionic conductivity are obtained through chemical crosslinking and ion coordination effect. Dual-material 3D printing is applied to package the hydrogel with elastomers. Due to the high sensitivity and reliability under both stretching and compressive deformation, the hydrogel sensors are applied to monitor various human motions. In addition, the hydrogel exhibits solvent-induced dehydration and excellent water-activated shape memory properties, which are greatly beneficial for its storage and applications in the biomedical field.
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http://dx.doi.org/10.1021/acsami.1c08438DOI Listing
July 2021

A High Strength but Fast Fracture-Self-Healing Thermoplastic Elastomer.

Macromol Rapid Commun 2021 Jul 17;42(14):e2100135. Epub 2021 Jun 17.

Key Laboratory of Science and Technology on High-Tech Polymer Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.

Herein, a new type of healable thermoplastic poly(urethane-urea) (PUU) elastomer with a unique dual dynamic network structure consisting of multi-strength hydrogen bonds and aromatic disulfide bonds, is designed and synthesized. The resultant PUU elastomer exhibits high tensile strength (41 MPa), great toughness (104 MJ m ), and excellent self-healing capability (completely severes, heals at 60 ℃ for just 1 h, and recovers more than 80% of the original tensile strength). Although the PUU possesses high-density hydrogen bonds, it is completely homogeneous without micro-phase separation. The unique dual dynamic network structure alleviates the adverse effects of strong molecular interactions on self-healing process, simultaneously endowing the polymer with outstanding mechanical properties and excellent self-healing capability at mild temperature. In addition, the underlying mechanism between performance and structure is revealed. The PUU has potential applications in soft robots and wearable electronics.
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http://dx.doi.org/10.1002/marc.202100135DOI Listing
July 2021

Exploration of a ternary deep eutectic solvent for the efficient extraction of plantamajoside, acteoside, quercetin and kaempferol from Plantago asiatica L.

Phytochem Anal 2021 Jun 16. Epub 2021 Jun 16.

College of Pharmacy, Jiangxi University of Traditional Chinese Medicine, Nanchang, Jiangxi, 330006, P.R. China.

Introduction: In the present study, ternary deep eutectic solvent-based ultrasound-assisted extraction was developed for the efficient extraction of plantamajoside, acteoside, quercetin and kaempferol from Plantago asiatica L.

Methodology: Six kinds of choline chloride-based ternary deep eutectic solvents (TDESs) were prepared as potential extraction solutions. In order to obtain optimal extraction efficiency, a series of extraction conditions were investigated by single-factor test and orthogonal test.

Results: The extraction efficiency of choline chloride/lactic acid/ethylene glycol (ChCl-LA-EG) was much higher than that of other TDESs. ChCl-LA-EG-11 synthesised with choline chloride, lactic acid and ethylene glycol (1:4:2) was considered to have a higher extraction efficiency. The optimal ultrasound-assisted extraction conditions were as follows: water content in ChCl-LA-EG-11, 50%; extraction temperature, 70°C; ratio of solid/liquid, 20 mg/mL; ultrasonic power, 60 W; extraction time, 35 min; pH of the solution, 8. Under the optimal extraction conditions, the extraction efficiencies of plantamajoside, acteoside, quercetin and kaempferol were 3.83 ± 0.41, 4.23 ± 0.45, 0.56 ± 0.15 and 0.19 ± 0.08 mg/g, respectively. The extraction efficiency of the total target components was 9.21 ± 0.63 mg/g, which was much higher than that of conventional solvents (water, methanol, ethanol, 50% methanol, 50% ethanol). The target components were isolated efficiently from the TDES solution by an AB-8 macroporous resin column with a recovery rate of 95.6%.

Conclusion: This study demonstrated that TDESs possessed excellent physical and chemical properties and had enormous potential for active component extraction of traditional Chinese medicinal materials.
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http://dx.doi.org/10.1002/pca.3071DOI Listing
June 2021

Utility of multi-parametric quantitative magnetic resonance imaging of the lacrimal gland for diagnosing and staging Graves' ophthalmopathy.

Eur J Radiol 2021 Aug 8;141:109815. Epub 2021 Jun 8.

Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510080, Guangdong Province, China. Electronic address:

Purpose: To explore radiological changes of the lacrimal gland (LG) in Graves' ophthalmopathy (GO) based on multi-parametric quantitative MRI and its clinical utility in LG diagnosis and activity in GO.

Methods: We enrolled 99 consecutive patients with GO (198 eyes) and 12 Graves' Disease (GD) patients (24 eyes) from July 2018 to June 2020. Clinical, laboratory, and MRI data were collected at the first visit. Based on clinical activity scores, eyes with GO were subdivided into active and inactive groups. T2-relaxation time (T2) and the absolute reduction in T1-relaxation time (ΔT1) were determined. After MRI and processing, we performed descriptive data analysis and group comparisons. Novel logistic regression predictive models were developed for diagnosing and staging GO. Diagnostic performance of MRI parameters and models was assessed by receiver operating characteristic curve analysis.

Results: LG in GO group had significantly higher T2 and ΔT1 values than the GD group [106.25(95.30,120.21) vs. 83.35(78.15,91.45), P<0.001, and 662.62(539.33,810.95) vs. 547.35(458.62,585.57), P = 0.002, respectively]. The GO group had higher T2 of LG indicating higher disease activity [110.93(102.54,127.67) vs. 93.29(87.06,101.96), P < 0.001]. Combining T2 and ΔT1 values of LG, Model I had higher diagnostic value for distinguishing GO from GD (AUC=0.94, 95 %CI: 0.89,0.99, P<0.001). Meanwhile, T2 of LG had higher diagnostic value for grading GO activity (AUC = 0.84, 95 %CI: 0.76,0.92, P<0.001).

Conclusions: Multi-parametric quantitative MRI parameters of the LG in GO were significantly altered. Novel models combining LG T2 and ΔT1 values showed excellent predictive performances in diagnosing GO. Furthermore, T2 of LG showed practical utility for staging GO.
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http://dx.doi.org/10.1016/j.ejrad.2021.109815DOI Listing
August 2021

High-throughput quantification of eighteen heterocyclic aromatic amines in roasted and pan-fried meat on the basis of high performance liquid chromatography-quadrupole-orbitrap high resolution mass spectrometry.

Food Chem 2021 Nov 18;361:130147. Epub 2021 May 18.

College of Light Industry and Food Sciences, Guangdong Key Laboratory of Science and Technology of Lingnan Special Food, Innovation Research Institute of Modern Agricultural Engineering, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China. Electronic address:

Triple quadrupole mass spectrometry has been the main technique for HAAs analysis in recent decade, while it requires extensive optimization of compound-dependent parameters. A novel method based on HPLC-Q-Orbitrap-HRMS was developed firstly for simultaneous determination of eighteen HAAs. Extraction and purification conditions were optimized and the developed method was validated in terms of linearity, accuracy and precision. Results indicated eighteen HAAs and two internal standards could be separated in 12 min using a gradient elution program. The full MS/dd-MS scan was adopted for analysis, which indicated favorable recoveries (71.3-114.8%) along with LODs and LOQs in the ranges of 0.02-0.6 and 0.05-2.0 μg/kg, respectively. Internal standards used for calibration could effectively reduce quantification errors produced by matrix effects. The validated method was successfully applied for HAAs analysis in roasted and pan-fried meat and was confirmed to be an alternative method when triple quadrupole mass spectrometry is absent in lab.
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http://dx.doi.org/10.1016/j.foodchem.2021.130147DOI Listing
November 2021

Synergistic Effects of Ladder and Cage Structured Phosphorus-Containing POSS with Tetrabutyl Titanate on Flame Retardancy of Vinyl Epoxy Resins.

Polymers (Basel) 2021 Apr 22;13(9). Epub 2021 Apr 22.

Key Laboratory of Science and Technology on High-Tech Polymer Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.

The cage and ladder structured phosphorus-containing polyhedral oligomeric silsesquioxanes (DOPO-POSS) have been synthesized through the hydrolytic condensation of 9,10-dihydro-9-oxa-10-phosphenanthrene-10-oxide (DOPO)-vinyl triethoxysilane (VTES). The unique ladder and cage-ladder structured components in DOPO-POSS endowed it with good solubility in vinyl epoxy resin (VE), and it was used with tetrabutyl titanate (TBT) to construct a phosphorus-silicon-titanium synergy system for the flame retardation of VE. Thermal stabilities, mechanical properties, and flame retardancy of the resultant VE composites were investigated by thermal gravimetric analysis (TGA), dynamic mechanical analysis (DMA), three-point bending tests, limiting oxygen index (LOI) measurement, and cone calorimetry. The experimental results showed that with the addition of only 4 wt% DOPO-POSS and 0.5 wt% TBT, the limiting oxygen index value (LOI) increased from 19.5 of pure VE to 24.2. With the addition of DOPO-POSS and TBT, the peak heat release rate (PHRR), total heat release (THR), smoke production rate (SPR), and total smoke production (TSP) were decreased significantly compared to VE-0. In addition, the VE composites showed improved thermal stabilities and mechanical properties comparable to that of the VE-0. The investigations on pyrolysis volatiles of cured VE further revealed that DOPO-POSS and TBT exerted flame retardant effects in gas phase. The results of char residue of the VE composites by SEM and XPS showed that TBT and DOPO-POSS can accelerate the char formation during the combustion, forming an interior char layer with the honeycomb cavity structure and dense exterior char layer, making the char strong with the formation of Si-O-Ti and Ti-O-P structures.
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http://dx.doi.org/10.3390/polym13091363DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8122454PMC
April 2021

Tetherin/BST2, a physiologically and therapeutically relevant regulator of platelet receptor signalling.

Blood Adv 2021 04;5(7):1884-1898

School of Physiology, Pharmacology, and Neuroscience, and.

The reactivity of platelets, which play a key role in the pathogenesis of atherothrombosis, is tightly regulated. The integral membrane protein tetherin/bone marrow stromal antigen-2 (BST-2) regulates membrane organization, altering both lipid and protein distribution within the plasma membrane. Because membrane microdomains have an established role in platelet receptor biology, we sought to characterize the physiological relevance of tetherin/BST-2 in those cells. To characterize the potential importance of tetherin/BST-2 to platelet function, we used tetherin/BST-2-/- murine platelets. In the mice, we found enhanced function and signaling downstream of a subset of membrane microdomain-expressing receptors, including the P2Y12, TP thromboxane, thrombin, and GPVI receptors. Preliminary studies in humans have revealed that treatment with interferon-α (IFN-α), which upregulates platelet tetherin/BST-2 expression, also reduces adenosine diphosphate-stimulated platelet receptor function and reactivity. A more comprehensive understanding of how tetherin/BST-2 negatively regulates receptor function was provided in cell line experiments, where we focused on the therapeutically relevant P2Y12 receptor (P2Y12R). Tetherin/BST-2 expression reduced both P2Y12R activation and trafficking, which was accompanied by reduced receptor lateral mobility specifically within membrane microdomains. In fluorescence lifetime imaging-Förster resonance energy transfer (FLIM-FRET)-based experiments, agonist stimulation reduced basal association between P2Y12R and tetherin/BST-2. Notably, the glycosylphosphatidylinositol (GPI) anchor of tetherin/BST-2 was required for both receptor interaction and observed functional effects. In summary, we established, for the first time, a fundamental role of the ubiquitously expressed protein tetherin/BST-2 in negatively regulating membrane microdomain-expressed platelet receptor function.
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http://dx.doi.org/10.1182/bloodadvances.2020003182DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8045503PMC
April 2021

OBP2 in the Midlegs of the Male Is Involved in the Perception of the Female-Biased Sex Pheromone 4-Allyl-2,6-dimethoxyphenol.

J Agric Food Chem 2021 Jan 4;69(1):126-134. Epub 2021 Jan 4.

Institute of Plant Health, ZhongKai University of Agriculture and Engineering, 510225 Guangzhou, Guangdong, China.

Short-range semiochemicals convey individual-specific information, which is important for final successful courtship and copulation. In this study, an electroantennography (EAG) instrument was used to determine the legs of male that might participate in the perception of 4-allyl-2,6-dimethoxyphenol (4-DMP), a female-biased cuticular hydrocarbon (CHC) component. By performing comparative RNA-seq analysis, nine differentially expressed OBPs between 4-DMP-stimulated (M) and unstimulated (M) male flies were screened out. Among the four downregulated OBPs, OBP2 exhibited the strongest binding to 4-DMP than OBP4, OBP19a, and OBP56h. Functional analyses confirmed that the reduction in transcript abundance of OBP2 led to a significant decrease in behavioral responses of male flies to 4-DMP. simulation revealed dramatic changes in the key residues and conformation between the two complexes, implying that OBP2 might activate different receptors after binding to 4-DMP or methyl eugenol (ME). The results of this study suggest that OBP2 mediates behavioral responses to 4-DMP and could be a promising molecular target for strategies of pest control.
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http://dx.doi.org/10.1021/acs.jafc.0c05945DOI Listing
January 2021

Petroleum extract of alleviates nasal symptoms by regulating the Th1-Th2 cytokine balance in a mouse model of Allergic Rhinitis.

Int J Med Sci 2021 1;18(2):555-563. Epub 2021 Jan 1.

Shanxi Key Laboratory of Otorhinolaryngology Head and Neck Cancer, First Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi, China.

is a traditional Chinese medicine that has long been used to treat allergies. In this study, we aimed to investigate the effect of a petroleum extract of (PEFF) in a mouse model of allergic rhinitis (AR) and to explore the underlying molecular mechanisms of action. An animal model of AR was established by sensitization and challenge of BALB/c mice with ovalbumin (OVA). PEFF was administered intranasally and AR nasal symptoms were assessed on a semi-quantitative scale according to the frequencies of nose rubbing and sneezing and the degree of rhinorrhea. The mechanism of action of PEFF was evaluated by histological analysis of nasal mucosa architecture and inflammatory status; ELISA-based quantification of serum OVA-specific IgE, interferon-γ (IFN-γ), and interleukin-4 (IL-4) concentrations; and immunohistochemical and western blot analysis of T-bet and GATA3 protein expression in nasal mucosa and spleen tissues. The results showed intranasal administration of PEFF alleviated AR symptom scores and reduced both the infiltration of inflammatory cells and tissue damage in the nasal mucosa. PEFF significantly decreased serum concentrations of OVA-specific IgE (<0.01) and IL-4 (<0.05) and significantly increased IFN-γ (<0.01). PEFF also upregulated the expression of T-bet protein (<0.05) but downregulated GATA3 protein (<0.05) in nasal mucosa and spleen tissues. In conclusion, PEFF effectively reduces AR nasal symptoms and serum IgE levels in a mouse model and may act by correcting the imbalance between Th1 and Th2 responses.
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http://dx.doi.org/10.7150/ijms.52915DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7757150PMC
January 2021

Hollow Mesoporous Carbon Spheres for High Performance Symmetrical and Aqueous Zinc-Ion Hybrid Supercapacitor.

Front Chem 2020 15;8:663. Epub 2020 Sep 15.

Hubei Key Laboratory of Ferro and Piezoelectric Materials and Devices, Faculty of Physics and Electronic Science, Hubei University, Wuhan, China.

Zinc-ion hybrid supercapacitors are a promising energy storage device as they simultaneously combine the high capacity of batteries and the high power of supercapacitors. However, the practical application of Zinc-ion hybrid supercapacitors is hindered by insufficient energy density and poor rate performance. In this study, a symmetrical zinc-ion hybrid supercapacitor device was constructed with hollow mesoporous-carbon nanospheres as electrode materials, and aqueous ZnSO adopted as an electrolyte. Benefiting from the mesoporous structure and high specific area (800 m/g) of the hollow carbon nanospheres, fast capacitor-type ion adsorption/de-adsorption on both the cathode and the anode can be achieved, as well as additional battery-type Zn/Zn electroplating/stripping on the anode. This device thus demonstrates outstanding electrochemical performance, with high capacity (212.1 F/g at 0.2 A/g), a high energy density (75.4 Wh/kg at 0.16 kW/kg), a good rate performance (34.2 Wh/kg energy density maintained at a high power density of 16.0 kW/kg) and excellent cycling stability with 99.4% capacitance retention after 2,500 cycles at 2 A/g. The engineering of this new configuration provides an extremely safe, high-rate, and durable energy-storage device.
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http://dx.doi.org/10.3389/fchem.2020.00663DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7533584PMC
September 2020

Contribution of Cation Addition to MnO Nanosheets on Stable Co O Nanowires for Aqueous Zinc-Ion Battery.

Front Chem 2020 23;8:793. Epub 2020 Sep 23.

Hubei Key Laboratory of Ferro and Piezoelectric Materials and Devices, Faculty of Physics and Electronic Science, Hubei University, Wuhan, China.

Zinc-based electrochemistry attracts significant attention for practical energy storage owing to its uniqueness in terms of low cost and high safety. In this work, we propose a 2.0-V high-voltage Zn-MnO battery with [email protected] [email protected] on carbon cloth as a cathode, an optimized aqueous ZnSO electrolyte with Mn additive, and a Zn metal anode. Benefitting from the architecture engineering of growing CoO nanorods on carbon cloth and subsequently deposited MnO on CoO with a two-step hydrothermal method, the binder-free zinc-ion battery delivers a high power of 2384.7 W kg, a high capacity of 245.6 mAh g at 0.5 A g, and a high energy density of 212.8 Wh kg. It is found that the Mn cations are converted to MnO during electrochemical operations followed by a phase transition into electroactive MnO in our battery system. The charge-storage mechanism of the MnO-based cathode is Zn/Zn and H insertion/extraction. This work shines light on designing multivalent cation-based battery devices with high output voltage, safety, and remarkable electrochemical performances.
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http://dx.doi.org/10.3389/fchem.2020.00793DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7539680PMC
September 2020

Physiological Characteristic Changes and Full-Length Transcriptome of Rose (Rosa chinensis) Roots and Leaves in Response to Drought Stress.

Plant Cell Physiol 2021 Feb;61(12):2153-2166

College of Landscape Architecture and Forestry, Qingdao Agricultural University, Qingdao, Shandong 266109, China.

Rose (Rosa chinensis) is the most important ornamental crops worldwide. However, the physiological and molecular mechanism of rose under drought stress remains elusive. In this study, we analyzed the changes of photosynthetic and phytohormone levels in the leaves and roots of rose seedlings grown under control (no drought), mild drought (MD) and severe drought stress. The total chlorophyll content and water use efficiency were significantly enhanced under MD in rose leaves. In addition, the concentration of ABA was higher in the leaves compared to the roots, whereas the roots accumulated more IAA, methylindole-3-acetic acid and indole-3-propionic acid. We also constructed the first full-length transcriptome for rose, and identified 96,201,862 full-length reads of average length 1,149 bp that included 65,789 novel transcripts. A total of 3,657 and 4,341 differentially expressed genes (DEGs) were identified in rose leaves and roots respectively. KEGG pathway analysis showed enrichment of plant hormone, signal transduction and photosynthesis are among the DEGs. 42,544 alternatively spliced isoforms were also identified, and alternative 3' splice site was the major alternative splicing (AS) event among the DEGs. Variations in the AS patterns of three genes between leaves and roots indicated the possibility of tissue-specific posttranscriptional regulation in response to drought stress. Furthermore, 2,410 novel long non-coding RNAs were detected that may participate in regulating the drought-induced DEGs. Our findings identified previously unknown splice sites and new genes in the rose transcriptome, and elucidated the drought stress-responsive genes as well as their intricate regulatory networks.
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http://dx.doi.org/10.1093/pcp/pcaa137DOI Listing
February 2021

Coaxial spinning fabricated high nitrogen-doped porous carbon walnut anchored on carbon fibers as anodic material with boosted lithium storage performance.

J Colloid Interface Sci 2021 Mar 27;586:371-380. Epub 2020 Oct 27.

Key Laboratory of Energy Materials Chemistry, Ministry of Education; Key Laboratory of Advanced Functional Materials, Autonomous Region; Institute of Applied Chemistry, College of Chemistry, Xinjiang University, Urumqi, 830046, Xinjiang, PR China.

Commercial graphite with low theoretical capacity cannot meet the ever-increasing requirement demands of lithium-ion batteries (LIBs) caused by the rapid development of electric devices. Rationally designed carbon-based nanomaterials can provide a wide range of possibilities to meet the growing requirements of energy storage. Hence, the porous walnut anchored on carbon fibers with reasonable pore structure, N-self doping (10.2 at%) and novel structure and morphology is designed via interaction of inner layer polyethylene oxide and outer layer polyacrylonitrile and polyvinylpyrrolidone during pyrolysis of the obtained precursor, which is fabricated by coaxial electrospinning. As an electrode material, the as-made sample shows a high discharge capacity of 965.3 mA h g at 0.2 A g in the first cycle, retains a capacity of 819.7 mA h g after 500 cycles, and displays excellent cycling stability (475.2 mA h g at 1 A g after 1000 cycles). Moreover, the capacity of the electrode material still keeps 260.5 mA h g at 5 A g after 1000 cycles. Therefore, the obtained sample has a bright application prospect as a high performance anode material for LIBs. Besides, this design idea paves the way for situ N-enriched carbon material with novel structure and morphology by coaxial electrospinning.
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http://dx.doi.org/10.1016/j.jcis.2020.10.100DOI Listing
March 2021

Polydatin inhibits ZEB1-invoked epithelial-mesenchymal transition in fructose-induced liver fibrosis.

J Cell Mol Med 2020 11 15;24(22):13208-13222. Epub 2020 Oct 15.

State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China.

High fructose intake is a risk factor for liver fibrosis. Polydatin is a main constituent of the rhizome of Polygonum cuspidatum, which has been used in traditional Chinese medicine to treat liver fibrosis. However, the underlying mechanisms of fructose-driven liver fibrosis as well as the actions of polydatin are not fully understood. In this study, fructose was found to promote zinc finger E-box binding homeobox 1 (ZEB1) nuclear translocation, decrease microRNA-203 (miR-203) expression, increase survivin, activate transforming growth factor β1 (TGF-β1)/Smad signalling, down-regulate E-cadherin, and up-regulate fibroblast specific protein 1 (FSP1), vimentin, N-cadherin and collagen I (COL1A1) in rat livers and BRL-3A cells, in parallel with fructose-induced liver fibrosis. Furthermore, ZEB1 nuclear translocation-mediated miR-203 low-expression was found to target survivin to activate TGF-β1/Smad signalling, causing the EMT in fructose-exposed BRL-3A cells. Polydatin antagonized ZEB1 nuclear translocation to up-regulate miR-203, subsequently blocked survivin-activated TGF-β1/Smad signalling, which were consistent with its protection against fructose-induced EMT and liver fibrosis. These results suggest that ZEB1 nuclear translocation may play an essential role in fructose-induced EMT in liver fibrosis by targeting survivin to activate TGF-β1/Smad signalling. The suppression of ZEB1 nuclear translocation by polydatin may be a novel strategy for attenuating the EMT in liver fibrosis associated with high fructose diet.
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http://dx.doi.org/10.1111/jcmm.15933DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7701525PMC
November 2020

Design, synthesis and structure-activity relationship studies of novel partial FXR agonists for the treatment of fatty liver.

Bioorg Chem 2020 11 2;104:104262. Epub 2020 Sep 2.

School of Pharmacy, Yancheng Teachers' University, Yancheng, PR China. Electronic address:

Nonalcoholic fatty liver disease (NAFLD) is now the most common chronic liver disease, while there is still no medicine available. Farnesoid X receptor (FXR) is considered as a potential target for the treatment of NAFLD, and there are several FXR agonists reached in clinical trials. Based on better safety, industry and academia are pursuing development of the partial FXR agonists. To extend the chemical space of existing partial FXR agonists, we performed a structure-activity relationship study based on previously reported partial agonist 1 by using bioisosteric strategy. All of these efforts resulted in the identification of novel partial FXR agonist 13, which revealed the best agonistic activity in this series. Notably, compound 13 significantly alleviated the hepatic steatosis and hepatic function index in methionine-choline deficient (MCD) induced db/db mice, a classical nonalcoholic steatohepatitis (NASH) model widely used in preclinical evaluation. These results suggested that partial FXR agonist 13 might be a promising lead compound worthy further researches.
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http://dx.doi.org/10.1016/j.bioorg.2020.104262DOI Listing
November 2020

MiR-581/SMAD7 Axis Contributes to Colorectal Cancer Metastasis: A Bioinformatic and Experimental Validation-Based Study.

Int J Mol Sci 2020 Sep 5;21(18). Epub 2020 Sep 5.

Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, School of Life Sciences, Northwest University, Xi'an 710069, China.

Metastasis is a well-known poor prognostic factor and primary cause of mortality in patients with colorectal cancer (CRC). Recently, with the progress of high through-put sequencing, aberrantly expressed non-coding RNAs (ncRNAs) were found to participate in the initiation and development of cancer. However, the mechanisms of ncRNA-mediated regulation of metastasis in CRC remain largely unknown. In this study, we systematically analyzed the expression network of microRNAs (miRNAs) and genes in CRC metastasis using bioinformatics, and discovered that the miR-581/SMAD7 axis could be a potential factor that drives CRC metastasis. A dual luciferase report assay and protein analysis confirmed the binding relationship between miR-581 and SMAD7. Further functional assays revealed that miR-581 inhibition could suppress cell proliferation and induce apoptosis in SW480 cells. Up-regulation or down-regulation of miR-581 could both affect cell invasion capacity and modulate epithelial to mesenchymal transition (EMT) via a SMAD7/TGFβ signaling pathway. In conclusion, our findings elucidated that miR-581/SMAD7 could be essential for CRC metastasis, and may serve as a potential therapeutic target for CRC patients.
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http://dx.doi.org/10.3390/ijms21186499DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7555590PMC
September 2020

Empirical prediction of patent pledge financing of pharmaceutical enterprises-A case study in Jiangsu China.

PLoS One 2020 4;15(6):e0233601. Epub 2020 Jun 4.

School of Intellectual Property, Nanjing University of Science and Technology, Nanjing, Jiangsu, China.

Financing by patent pledge is an important way for small- and medium-sized pharmaceutical enterprises to address financing problems. In this study, eight indexes are analyzed considering both the pledge patent value and pledger credit value. And a prediction model for the patent pledge financing amount for pharmaceutical enterprises is constructed for the first time using the analytic hierarchy process and the fuzzy comprehensive evaluation method. Three levels of financing amount are concluded through the prediction model and prediction results corresponding with the financing amount are displayed. This model was designed to help small- and medium-sized pharmaceutical enterprises get access to financing through patent pledge to relieve their financial stress. At the same time, it provides guides for pledgees and policymakers to improve the efficiency and quality of patent pledge. This work is reliable and valid in that it constructs this prediction model based on systematical data from official data sources.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0233601PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7271991PMC
August 2020

Isolation, purification, characterization and immunostimulatory activity of an exopolysaccharide produced by Lactobacillus pentosus LZ-R-17 isolated from Tibetan kefir.

Int J Biol Macromol 2020 May 7;158:408-419. Epub 2020 May 7.

College of Food Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, PR China. Electronic address:

In this study, three strains of lactic acid bacteria isolated from Tibetan kefir grains, including two strains of Lactobacillus pentosus LZ-R-17 and L. helveticus LZ-R-5, and one strain of Lactococcus lactis subsp. lactis LZ-R-12. The ability of three strains to produce exopolysaccharide (EPS) was tested, and L. pentosus LZ-R-17 was found to have the highest EPS yield. One EPS (R-17-EPS) was isolated from the fermented milk by L. pentosus LZ-R-17 and purified by DEAE-52 anion exchange chromatography. Furthermore, R-17-EPS preliminary structure and macrophage immunomodulatory activity in vitro were investigated. On the basis of the analytical results of ultraviolet-visible spectrum, Fourier transform-infrared spectrum, monosaccharide composition analysis and one-dimensional and two-dimensional nuclear magnetic resonance (NMR) spectra, R-17-EPS was found to have an average molecular weight of 1.20 × 10 Da and was composed of galactose and glucose residues with a molar ratio of 1.00:3.15. NMR analysis revealed that the R-17-EPS was a linear hetero-galactoglucan containing repeating units of →2)-α-D-Galp-(1 → 4)-β-D-Glcp-(1 → 4)-β-D-Glcp-(1 → 4)-β-D-Glcp-(1→. In addition, R-17-EPS could effectively enhanced the proliferation, phagocytosis, nitric oxide and cytokines production of RAW264.7 cells, suggesting that R-17-EPS had potent immunostimulatory activity and could be explored as immunomodulator in functional food and/or medicine fields.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.05.027DOI Listing
May 2020

Controlling layered Ruddlesden-Popper perovskites via solvent additives.

Nanoscale 2020 Apr 23;12(13):7330-7338. Epub 2020 Mar 23.

Wuhan National Laboratory for Optoelectronics, School of Optoelectronic Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.

Layered Ruddlesden-Popper (RP) phase perovskites, with a formula of A'MAPb3 (where A' is an organic cation, MA is methylammonium, n is the integer for the number of inorganic sheets [PbI] between the organic cation spacers), are of high interest due to their chemical stability. However, the low-n phases (e.g., n = 1, 2) not only act as carrier traps, but also hinder carrier transport within the layered RP perovskites, leading to a decreased photovoltaic performance for their corresponding devices. Herein, we report that a solvent additive-induced Ostwald ripening process effectively promotes the reduction of low-n phases and uniform RP perovskites composition. Note that the solvent added, such as ethylene glycol as an example, should have selective solubility to organic cations, and be less volatile but have a higher boiling point than the host solvents such as N,N-dimethylformamide (DMF). During fast spin-coating at room temperature, the host solvent DMF quickly evaporates while the low-n phase perovskite films are formed due to a smaller nucleation barrier, allowing the contained solvent additive, ethylene glycol, to act as a plasticizer. Then, annealing at 100 °C, causes a slow release of the restrained solvent additive which recrystallizes the perovskite grains with low-n phases into high-n phases (e.g., n≥3) in the (ClPEA)MAPbI (where ClPEA is 2-(4-chlorophenyl)ethanaminium) layered RP phase perovskites. When used in solar cells, the device with a configuration of ITO/PEDOT:PSS/RP perovskite/PCBM/BCP/Ag showed an enhanced 11% power conversion efficiency, which can be attributed to the decreased trap-state density and the increased carrier transport induced by the solvent additive.
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http://dx.doi.org/10.1039/c9nr10382aDOI Listing
April 2020

Carbonic Anhydrase Inhibitors suppress platelet procoagulant responses and in vivo thrombosis.

Platelets 2020 Oct 1;31(7):853-859. Epub 2020 Jan 1.

School of Physiology, Pharmacology and Neuroscience, University of Bristol , Bristol, UK.

Carbonic anhydrase (CA) inhibitors have a long history of safe clinical use as mild diuretics, in the treatment of glaucoma and for altitude sickness prevention. In this study, we aimed to determine if CA inhibition may be an alternative approach to control thrombosis. We utilized a high-resolution dynamic imaging approach to provide mechanistic evidence that CA inhibitors may be potent anti-procoagulant agents and effective anti-thrombotics . Acetazolamide and methazolamide, while sparing platelet secretion, attenuated intracellular chloride ion entry and suppressed the procoagulant response of activated platelets and thrombosis . The chemically similar N-methyl acetazolamide, which lacks CA inhibitory activity, did not affect platelet procoagulant response . Outputs from rotational thromboelastometry did not reflect changes in procoagulant activity and reveal the need for a suitable clinical test for procoagulant activity. Drugs specifically targeting procoagulant remodeling of activated platelets, by blockade of carbonic anhydrases, may provide a new way to control platelet-driven thrombosis without blocking essential platelet secretion responses.
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http://dx.doi.org/10.1080/09537104.2019.1709632DOI Listing
October 2020

Construction and Validation of an Immune-Related Prognostic Model Based on TP53 Status in Colorectal Cancer.

Cancers (Basel) 2019 Nov 4;11(11). Epub 2019 Nov 4.

Institute of Preventive Genomic Medicine, School of Life Sciences, Northwest University, Xi'an 710069, China.

Growing evidence has indicated that prognostic biomarkers have a pivotal role in tumor and immunity biological processes. TP53 mutation can cause a range of changes in immune response, progression, and prognosis of colorectal cancer (CRC). Thus, we aim to build an immunoscore prognostic model that may enhance the prognosis of CRC from an immunological perspective. We estimated the proportion of immune cells in the GSE39582 public dataset using the CIBERSORT (Cell type identification by estimating relative subset of known RNA transcripts) algorithm. Prognostic genes that were used to establish the immunoscore model were generated by the LASSO (Least absolute shrinkage and selection operator) Cox regression model. We established and validated the immunoscore model in GEO (Gene Expression Omnibus) and TCGA (The Cancer Genome Atlas) cohorts, respectively; significant differences of overall survival analysis were found between the low and high immunoscore groups or TP53 subgroups. In the multivariable Cox analysis, we observed that the immunoscore was an independent prognostic factor both in the GEO cohort (HR (Hazard ratio) 1.76, 95% CI (confidence intervals): 1.26-2.46) and the TCGA cohort (HR 1.95, 95% CI: 1.20-3.18). Furthermore, we established a nomogram for clinical application, and the results suggest that the nomogram is a better predictive model for prognosis than immunoscore or TNM staging.
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http://dx.doi.org/10.3390/cancers11111722DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6895875PMC
November 2019

Arrestin-3 differentially regulates platelet GPCR subsets.

Platelets 2020 Jul 4;31(5):641-645. Epub 2019 Nov 4.

School of Physiology, Pharmacology and Neuroscience, University of Bristol , Bristol, UK, BS8 1TD.

The principal demonstrated role of the nonvisual arrestins is to limit G protein-coupled receptor (GPCR) signaling. Nonetheless, a direct demonstration of this fundamental ability in platelets remains lacking, despite the prominent role played by GPCRs in platelet activation. This paper describes the basic characterization of the activatory responses of platelets from mice lacking arrestin-3 (arr3-/-), revealing pleiotropic roles dependent on GPCR ligand. Functionally, arrestin-3 acts as a brake on platelet aggregation regardless of ligand tested. Downstream of P2Y receptors, arr3-/- mice show increased secretion and integrin activation mirrored by enhanced intracellular calcium signaling and global PKC-dependent phosphorylation. Furthermore, P2Y12 receptor (P2Y12R) activity as assessed by ADP-mediated reduction of VASP phosphorylation is enhanced in arr3-/-mice. Downstream of PAR receptors there are similar increases in secretion and integrin activation in arr3-/- mice, together with enhanced PKC activity. Last, in arr3-/- mice the TP receptor displays unaltered PKC activity but markedly reduced calcium responses, which together with the kinetics of the aggregation response suggested a unique positive regulatory role for arrestin-3 in TP signaling. Overall, this paper reveals pleiotropic roles for arrestin-3 dependent on GPCR ligand describing for the first time a negative regulatory function for arrestin-3 in platelets.
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http://dx.doi.org/10.1080/09537104.2019.1686754DOI Listing
July 2020

Effect of Ionic Composition on Physicochemical Properties of Mono-Ether Functional Ionic Liquids.

Molecules 2019 Aug 27;24(17). Epub 2019 Aug 27.

Key Laboratory for Utility of Environment-Friendly Composite Materials and Biomass in Universities of Gansu Province, Department of Chemical Engineering, Northwest Minzu University, Lanzhou 730000, China.

Tunable properties prompt the development of different "tailor-made" functional ionic liquids (FILs) for specific tasks. FILs with an ether group are good solvents for many organic compounds and enzymatic reactions. However, ionic composition influences the solubility by affecting the physiochemical properties of these FILs. To address the structure effect, a series of novel FILs with a mono-ether group (ME) based on imidazole were prepared through cationic functionalization and anionic exchange reactions, and characterized by NMR, mass spectroscopy, and Thermogravimetric analysis (TGA). The effect of ionic composition (cationic structure and anions) on density, viscosity, ionic conductivity, electrochemical window, and thermal properties of these ME-FILs were systematically investigated. In general, the viscosity and heat capacity increases with the bigger cationic volume of ME-FILs; in particular, the 2-alkyl substitution of imidazolium enhances the viscosity remarkably, whereas the density and conductivity decrease on the condition of the same [NTf] anion; For these ME-FILs with the same cations, the density follows the order of [NTf] > [PF] > [BF]. The viscosity follows the order of [PF] > [BF] > [NTf]. Ion conductivity follows the order of [NTf] ≈ [BF] > [PF]. It is noted that the dynamic density has a good linear relationship with the temperature, and the slopes are the same for all ME-FILs. Furthermore, these ME-FILs have broad electrochemical windows and glass transition temperatures in addition to a cold crystallization and a melt temperature for ME-FIL. Therefore, the cationic structure and counter anion affect the physicochemical properties of these ME-FILs together.
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http://dx.doi.org/10.3390/molecules24173112DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6749295PMC
August 2019

Ice-bath assisted sodium hydroxide purification coupled with GC-MS/MS analysis for simultaneous quantification of ethyl carbamate and 12 N-nitrosoamines in yellow rice wine and beer.

Food Chem 2019 Dec 17;300:125200. Epub 2019 Jul 17.

College of Light Industry and Food Sciences, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China.

Ethyl carbamate (EC) and N-nitrosoamines (NAs) are toxic contaminants which can be typically formed in fermented alcoholic beverages. In the present work, a novel approach for simultaneous analysis of EC and NAs in beer and yellow rice wine based on ice-bath assisted sodiumhydroxide purification and GC-MS/MS was firstly established. Samples were extracted with acetonitrile-ethyl acetate after addition of internal standards. The extraction solution system was purified by sodiumhydroxide solid under ice-bath. After concentration, target analytes were separated on a HP-INNOWAX quartz capillary column and determined under dynamic multiple reactions monitoring mode of MS/MS. The limits of detection and quantification (LOD and LOQ), matrix effect, recovery and precision of the method were evaluated. Results were linear in the concentration range 2-200 μg/L for all analytes of interest, with regression coefficients higher than 0.999. LODs and LOQs were in the ranges of 0.1-0.5 μg/kg and 0.5-1.5 μg/kg, respectively. The mean recoveries at three spiked levels were between 81.5% and 121.0%. The intra- and inter-day precisions were in the ranges of 2.2-9.4% and 1.6-7.9%, respectively. The validated method was successfully applied to determine thirteen targets in commercial beer and yellow rice wine. EC was detected in all beers and yellow rice wines with the concentrations ranging from 1.18 to 22.90 μg/L. Results indicated wide EC contamination and confirmed its urgency for monitoring EC in fermented alcoholic beverages.
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http://dx.doi.org/10.1016/j.foodchem.2019.125200DOI Listing
December 2019

Evaluation of the sp. 99-125 Lipase Positional Selectivity for 1,3-Diolein Synthesis.

Biomed Res Int 2019 20;2019:4318631. Epub 2019 May 20.

School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an 223003, China.

In this study, comparative experiments were carried out to investigate the positional selectivity of sp. 99-125 lipase in preparing 1,3-diolein by using medium engineering strategy. The results indicated that the diolein yield was markedly enhanced from 56.5% to 86.7% with increasing log⁡ values of the solvents, while the selectivity of the examined lipase for the over the hydroxyl of glycerol was decreased, thus leading to a reduced 1,3-diolein to 1,2-diolein ratio. To evaluate the possibility of industrial enzymatic production of 1,3-diolein, larger-scale experiments were assessed. After being used repeatedly for eight batches, the diolein content reached 95.1%, while the 1,3-diolein to 1,2-diolein ratio was 7:1 following purification. Results of the level experiments significantly demonstrated the practicability of the enzymatic process and the efficiency of the purification strategy for the product.
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http://dx.doi.org/10.1155/2019/4318631DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6545781PMC
December 2019

Effect of ultrasound-assisted extraction on physicochemical properties and TLR2-affinity binding of the polysaccharides from Pholiota nameko.

Int J Biol Macromol 2019 Aug 30;135:1020-1027. Epub 2019 May 30.

Tianjin Key Laboratory of Food Biotechnology, Faculty of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, PR China.

The effect of the ultrasonic treatment on the physicochemical properties, oil-holding capacities, foaming capacities, and TLR2-affinity of the polysaccharides from Pholiota nameko (PNPS), was evaluated. Compared with the protein content of PNPS before ultrasonic treatment, the protein content of PNPS all presented a decrease under different ultrasonic conditions. The viscosity of PNPS showed a decrease when the ultrasonic intensity was strong enough, as well as the molecular weight. The oil-holding capacity and the foaming capacity of PNPS showed a continuous increasing trend with the increase of the ultrasonic treatment time under a set ultrasonic power of 400 W. Further, the ultrasonic operation could induce the decrease of the affinity binding between PNPS and the receptor proteins TLR2. These data confirmed that applying the ultrasonic treatment could obtain PNPS with high carbohydrate contents, low viscosity and low TLR2-affinity under proper ultrasonic condition.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.05.177DOI Listing
August 2019

MicroRNA-3607 inhibits the tumorigenesis of colorectal cancer by targeting DDI2 and regulating the DNA damage repair pathway.

Apoptosis 2019 08;24(7-8):662-672

Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, School of Life Sciences, Northwest University, Taibai North Road 229, Xi'an, 710069, Shaanxi, China.

Mutations in the DNA damage repair (DDR) pathway are frequently detected in colorectal cancer (CRC). The dysregulation of miRNAs, such as oncogenes or tumor suppressors, participates in CRC tumorigenesis. A previous study showed that low miR-3607 expression correlated with poor survival in prostate cancer patients, but its role in CRC remains unclear. In this study, we analyzed miR-3607 expression Pan-Cancer data from the NCI's Genomic Data Commons (GDC) and found that miR-3607 was downregulated in lymphatic invasion patients and in recurrent cancer and correlated with Pan-Cancer patient survival. Functional studies indicated that the overexpression of miR-3607 decreased CRC cell proliferation, migration and invasion. Additionally, we used gene set enrichment analysis (GSEA), Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and a protein-protein interaction network to demonstrate that miR-3607 affects the DDR pathway. Luciferase reporter and apoptosis assays confirmed that DNA damage inducible 1 homolog 2 (DDI2) is the functional target of miR-3607. Therefore, miR-3607 inhibits the tumorigenesis of CRC probably by suppressing the oncogene DDI2, and it might serve as a novel target for CRC prediction and therapy.
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http://dx.doi.org/10.1007/s10495-019-01549-5DOI Listing
August 2019

Resveratrol downregulates PCSK9 expression and attenuates steatosis through estrogen receptor α-mediated pathway in L02 cells.

Eur J Pharmacol 2019 Jul 11;855:216-226. Epub 2019 May 11.

Jiangsu Key Laboratory of Regional Resource Exploitation and Medicinal Research, Huaiyin Institute of Technology, Huai'an, 223003, China.

Proprotein convertase subtilisin kexin type 9 (PCSK9) is a promising target for treating dyslipidemia and atherosclerosis. Circulating PCSK9 levels are closely related to hepatic steatosis severity and endogenous estrogen levels. Resveratrol (RSV) is a phytoestrogens that protects against atherosclerosis and hepatic steatosis. Thus, we sought to determine whether RSV had the activities to inhibit PCSK9 expression and to attenuate lipid accumulation in free fatty acid (FFA)-induced L02 cells via ERα pathway. In this study, RSV (10, 20 μM) were cultured with L02 cells in the presence of FFA (oleate:palmitate = 2:1). RSV significantly reduced the number of lipid droplets and intracellular TG in steatotic L02 cells, and Oil red O staining and Nile red staining had the same results. Western blot analysis showed that RSV significantly reduced apoB secretion and intracellular microsomal triglyceride transporter (MTP) expression under lipid-rich conditions. Treatment with RSV reduced expression of PCSK9 while maintaining LDL receptor (LDLR) expression and LDL uptake. RSV decreased SREBP-1c expression at both mRNA and protein levels. In addition, RSV significantly reduced the expression of liver X receptor α (LXRα) mRNA in L02 cells, but did not affect the expression of liver X receptor β (LXRβ) mRNA. The luciferase reporter assays suggested that RSV inhibited SREBP-mediated transcription of PCSK9. Finally, these results could be partly reversed by Estrogen receptor α (ERα) gene silencing. These results suggest that RSV attenuates steatosis and PCSK9 expression through down-regulation of SREBP-1c expression, at least in part through ERα-mediated pathway.
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http://dx.doi.org/10.1016/j.ejphar.2019.05.019DOI Listing
July 2019

Atomic-Scale Tailoring of Organic Cation of Layered Ruddlesden-Popper Perovskite Compounds.

J Phys Chem Lett 2019 Apr 2;10(8):1813-1819. Epub 2019 Apr 2.

Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information , Huazhong University of Science and Technology , Wuhan 430074 , Hubei , P.R. China.

Layered Ruddlesden-Popper (RP) phase perovskite compounds have emerged as promising photovoltaic materials for solar cell applications, but they suffer from poor absorption and strong exciton-binding energy. Herein, fluoro-, chloro-, and bromo-substitutions on the 4-position of the phenyl group in the component CHCHCHNH (PEA) are designed and synthesized to investigate their effect on the layered RP type H-PEAMAPbI (MA = CHNH) perovskite as an example. Single-crystal X-ray diffraction and temperature-dependent photoluminescence spectroscopy characterization reveal the electron-withdrawing halogen in organic cations decreases the distortion of inorganic sheets and significantly reduces the impact of two-dimensional quantum and dielectric confinement. This is further verified with an increased visible absorption and lower exciton-binding energy for these new layered RP-type perovskite compounds. A planar structured perovskite solar cell using an F-PEAMAPbI layer achieves a power conversion efficiency of 5.8%, which is better than that of the reference H-PEAMAPbI.
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http://dx.doi.org/10.1021/acs.jpclett.9b00479DOI Listing
April 2019

Superstretchable and Processable Silicone Elastomers by Digital Light Processing 3D Printing.

ACS Appl Mater Interfaces 2019 Apr 3;11(15):14391-14398. Epub 2019 Apr 3.

Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , People's Republic of China.

A series of photosensitive resins suitable for the production of silicone elastomers through digital light processing 3D printing are reported. Based on thiol-ene click reaction between a branched mercaptan-functionalized polysiloxane and different-molecular-weight vinyl-terminated poly(dimethylsiloxane), silicone elastomers with tunable hardness and mechanical properties are obtained. Printed elastomeric objects show high printing resolution and excellent mechanical properties. The break elongation of the silicone elastomers can get up to 1400%, which is much higher than the reported UV-cured elastomers and is even higher than the most stretchable thermocuring silicone elastomers. The superstretchable silicone elastomers are then applied to fabricate stretchable electronics with carbon nanotubes-doped hydrogel. The printable and processable silicone elastomers have great potential applications in various fields, including soft robotics, flexible actuators, and medical implants.
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http://dx.doi.org/10.1021/acsami.9b03156DOI Listing
April 2019
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