Publications by authors named "Shiqing Li"

65 Publications

Highly stable graphene oxide composite nanofiltration membrane.

Nanoscale 2021 Jun 27;13(22):10061-10066. Epub 2021 May 27.

Xiamen University Center for Membrane Application and Advancement, College of Materials, Xiamen University, Xiamen 361005, Fujian, China.

Graphene oxide (GO) based membranes are promising for advanced nanofiltration in water treatments but there is a need to improve water flux and membrane stability. Although the interlayer distance of GO membranes can be expanded using intercalants to improve permeability, achieving uniform intercalation without the added complication of water-induced swelling is challenging. Herein, we report the fabrication of GO hybrid lamellar membranes with controllable layer structures to achieve high performance in nanofiltration. The interlayer spacing of the GO hybrid membrane is regulated using TiO intercalants of different sizes, while the stability of GO membranes is enhanced by encapsulating with polyethyleneimine (PEI). The optimal composite membrane delivers a pure water-flux up to 26.0 L m h bar with a 99.9% rejection of methylene blue and eosin under an ultra-low pressure nanofiltration condition. More importantly, the composite membrane sustains good cycling stability after 5 filtration cycles of dye, which enables the potential industrial application in realizing ultra-stable GO based membranes.
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http://dx.doi.org/10.1039/d1nr01823jDOI Listing
June 2021

Response of maize yield and nitrogen leaching to combining controlled-release urea and normal urea under different surface mulching.

J Sci Food Agric 2021 Mar 14. Epub 2021 Mar 14.

State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, China.

Background: A one-off application of combining controlled-release urea (CRU) and conventional urea has been recommended for the reduction of nitrogen (N) loss and improvement of grain yield. However, the effects of combining CRU and urea with different surface mulching has not been studied in detail, and the underlying agronomical and physiological mechanisms need to be more clearly understood.

Result: A 3-year field study was conducted to determine the effects of combining CRU and urea with different surface mulching on dry matter, N accumulation and translocation, nitrate nitrogen (NO -N) residuals and loss in maize grown under rain-fed conditions. Three surface mulching [plastic film mulching (FM), straw mulching (SM) and no mulching (NM)] as well as three N fertilization [combining CRU and urea with 1:2 as the baseline application (NC), a split urea application with 4:3:3 (NU) and a N control (N0)] were used. The FM under NC fertilization increased N uptake, decreased NO -N residual in the deep soil layer, and decreased N loss. The FM, SM and NM under NC fertilization increased 3-year mean grain yields by 5.8%, 4.0% and 4.6%, respectively, compared to that under NU fertilization. The FM under NC fertilization showed the highest grain yield and economic return.

Conclusion: Properly managing N application by mixing CRU and urea in a one-off application combined with plastic film mulching may have the potential to provide a better compromise among grain yield, N loss and economic returns for maize in rain-fed farmland. © 2021 Society of Chemical Industry.
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http://dx.doi.org/10.1002/jsfa.11201DOI Listing
March 2021

High leaf area index inhibits net primary production in global temperate forest ecosystems.

Environ Sci Pollut Res Int 2021 May 9;28(18):22602-22611. Epub 2021 Jan 9.

State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, 712100, People's Republic of China.

Within limited growth age in some regions, forest production, including gross primary production (GPP) and net primary production (NPP), was linearly correlated with leaf area index (LAI). However, over wide range of growth age in the global scale, LAI patterns of forest production are unclear. Here, we compiled a subset from the Global Soil Respiration Database (SRDB) for global temperate forest ecosystems. The subset database mainly included forest production, soil respiration, and LAI data in 493 study sites over wide range of forest growth age (0-500 years). The results showed that LAI initially increased rapidly, reached a peak at juvenility, decreased slowly until maturity, and again increased possibly with further forest aging (R = 0.21, P < 0.001). We found that the dynamics of both GPP and NPP across global temperate forest ecosystems were driven by LAI. GPP initially increased and subsequently stabilized with increasing LAI. NPP peaked at LAI of about 5.6 m m, and subsequently decreased. The decrease in NPP resulted from the asymptotic increase in GPP and the continuing decrease in the NPP/GPP ratio with increasing LAI. The decline in the NPP/GPP ratio resulted from the significant increase in autotrophic respiration (R), and especially after canopy closure, R increased more quickly with increasing LAI than GPP. These results will improve our understanding of the control of LAI on ecosystem production.
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http://dx.doi.org/10.1007/s11356-020-11928-0DOI Listing
May 2021

The C-H functionalization of organic cations: an interesting and fresh journey.

Org Biomol Chem 2020 Nov;18(43):8810-8826

Guangxi Key Laboratory of Electrochemical and Magneto-Chemical Function Materials, College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, China.

Organic ionic compounds, especially those with organic cations, are commonly applied in ionic liquids (ILs), organocatalysts, (a)NHC ligands, ion recognition, and optoelectronic materials. The direct C-H functionalization of organic cations offers valuable opportunities for the rapid assembly of diverse functionalized cations and for their further exploitation in material science applications. This review summarizes the substantial progress that has been made in the C-H functionalization of organic cations from the 1960s to May 2020, including transition metal-mediated/catalyzed C-H alkylation, arylation, and annulation, and photo-induced C-H functionalization. Substrate scopes, limitations, regio-/chemoselectivity, and reaction mechanisms are discussed. In addition, the applications of some new organic functional materials are briefly exemplified. This review also aims to serve as a reminder that much care should be taken when using organic ionic compounds as solvents, because they can behave as reactants that can break up desired coupling reactions.
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http://dx.doi.org/10.1039/d0ob01453bDOI Listing
November 2020

Excite Spoof Surface Plasmons with Tailored Wavefronts Using High-Efficiency Terahertz Metasurfaces.

Adv Sci (Weinh) 2020 Oct 5;7(19):2000982. Epub 2020 Aug 5.

State Key Laboratory of Surface Physics Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education) Fudan University Shanghai 200433 China.

Spoof surface plasmons (SSPs) play crucial roles in terahertz (THz) near-field photonics. However, both high-efficiency excitation and wavefront engineering of SSPs remain great challenges, which hinder their wide applications in practice. Here, a scheme is proposed to simultaneously achieve these two goals efficiently using a single ultracompact device. First, it is shown that a gradient meta-coupler constructed by high-efficiency Pancharatnam-Berry (PB) meta-atoms can convert circularly polarized (CP) THz beams into SSPs with absolute efficiency up to 60%. Encoding a parabolic phase profile into the meta-coupler based on the PB mechanism, it is demonstrated that the device can covert CP beams into SSPs with focusing or defocusing wavefronts, dictated by the chirality of the incident wave. Finally, two distinct chirality-dependent phase distributions are encoded into the meta-coupler design by combining the PB and resonance phase mechanisms, and it is demonstrated that the resulting meta-device can achieve SSP excitations with chirality-delinked bifunctional wavefront engineering. THz near-field experiments are performed to characterize all three devices, in excellent agreement with full-wave simulations. The results pave the road to realize ultracompact devices integrating different functionalities on near-field manipulations, which can find many applications (e.g., optical sensing, imaging, on-chip photonics, etc.) in different frequency domains.
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http://dx.doi.org/10.1002/advs.202000982DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7539192PMC
October 2020

MrHex1 is Required for Woronin Body Formation, Fungal Development and Virulence in .

J Fungi (Basel) 2020 Sep 14;6(3). Epub 2020 Sep 14.

CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.

The Woronin body (WB) is a peroxisome-derived dense-core vesicle, a self-assembling hexagonal crystal of a single protein Hex1. This organelle is specific to the ascomycete fungi belonging to the Pezizomycotina subphylum by functioning in sealing septal pores in response to mycelium damage and the control of cell heterogeneity. We retrieved all available Hex1-domain containing proteins of different fungi from the GenBank database and found considerable length variations among 460 obtained Hex1 proteins. However, a highly conserved Hex1 domain containing 75 amino acid residues with a specific S/A-R/S-L consensus motif for targeting peroxisome is present at the carboxy-terminus of each protein. A homologous gene, named , was deleted in the entomopathogenic fungus It was found that MrHex1 was responsible for WB formation in and involved in sealing septal pores to maintain cell integrity and heterogeneity. Different assays indicated that, relative to the wild-type (WT) strain, ∆ demonstrated a growth defect on a solid medium and substantial reductions of conidiation, appressorium formation and topical infectivity against insect hosts. However, there was no obvious virulence difference between WT and mutants during injection of insects. We also found that ∆ could tolerate different stress conditions like the WT and the gene-rescued mutant of , which is in contrast to the reports of the stress-response defects of the null mutants of other fungal species. In addition to revealing the phenotypic/functional alterations of the deletion mutants between different pathotype fungi, the results of this study may benefit the understanding of the evolution and WB-control of fungal entomopathogenicity.
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http://dx.doi.org/10.3390/jof6030172DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7559983PMC
September 2020

Adjudin-loaded redox-sensitive paclitaxel-prodrug micelles for overcoming multidrug resistance with efficient targeted Colon cancer therapy.

Drug Deliv 2020 Dec;27(1):1094-1105

Department of Gastrointestinal Surgery, The First Affiliated Hospital of Bengbu Medical College, Bengbu, China.

Multidrug resistance (MDR) is the primary cause for the failure of chemotherapy in the treatment of colon cancer. Recent research has indicated that the combination of a chemotherapeutic agent and a mitochondrial inhibitor might represent a promising strategy to help overcome MDR. However, for this approach to be clinically effective, it is important that the two drugs can be actively and simultaneously delivered into tumor cells at an optimal ratio and completely released drug within cells. To address these challenges, we designed and prepared a folate receptor-targeted and redox-responsive drug delivery system (FA- -P/A) that was able to co-deliver paclitaxel (PTX) and adjudin (ADD) to reverse colon cancer MDR. The PTX prodrug was obtained by conjugating PTX to dextrin via a disulfide-linkage. Then, folic acid (FA) was modified on the PTX prodrug. Finally, ADD, a mitochondrial inhibitor, was encapsulated in the PTX prodrug-formed micelles. A series of in vitro and in vivo experiments subsequently demonstrated that FA- -P/A can effectively reverse MDR by increasing cell uptake, inhibiting PTX efflux, and improving drug release.
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http://dx.doi.org/10.1080/10717544.2020.1797245DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7470106PMC
December 2020

Cu-Catalyzed tandem N-arylation of phthalhydrazides with cyclic iodoniums to yield dihydrobenzo[c]cinnolines.

Org Biomol Chem 2020 07;18(25):4824-4830

Guangxi Key Laboratory of Electrochemical and Magneto-Chemical Function Materia, College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, P. R. China.

Dihydrocinnolines have significant pharmacological properties. Herein, we investigate a Cu-catalyzed tandem N-arylation reaction of phthalhydrazides with cyclic iodonium salts to construct dihydrobenzo[c]cinnoline derivatives. Various iodonium salts, such as symmetrical, unsymmetrical, aryl-aryl, and aryl-heteroaryl ones, could react with phthalhydrazides smoothly and give the title products in moderate to high yields. Moreover, the -NH2 group, which has been diarylated by cyclic iodonium salts to form carbazoles in previous reports, is also well tolerated in this work.
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http://dx.doi.org/10.1039/d0ob00894jDOI Listing
July 2020

Elucidation of colon-protective efficacy of diosgenin in experimental TNBS-induced colitis: inhibition of NF-κB/IkB-α and Bax/Caspase-1 signaling pathways.

Biosci Biotechnol Biochem 2020 Sep 11;84(9):1903-1912. Epub 2020 Jun 11.

Gastroenterology Department, Nanchong Central Hospital, The Second Clinical Medical College, North Sichuan Medical , Nanchong, Sichuan, China.

The aim of present investigation was to elucidate the unrevealed beneficial role of diosgenin against an experimental model of TNBS (2,4,6-trinitrobenzenesufonic acid)-induced ulcerative colitis (UC). Colitis was induced in Sprague-Dawley rats by intrarectal administration of TNBS (in 50% ethanol). Then animals were treated with diosgenin (50, 100, and 200 mg/kg) for 14 days. Various biochemical, behavioral, molecular, and histological analysis was performed. Diosgenin significantly decreased (0.05) TNBS-induced elevated colonic oxido-nitrosative damage, myeloperoxidase, hydroxyproline, mRNA expressions of proinflammatory cytokines (TNF-α, IL-1β, IL-6, and IFN-γ) and inflammatory markers (iNOs and COX-2) induced by TNBS. Western blot analysis relevated that TNBS-induced up-regulated protein expressions of NF-κB, IκBα, Bax, and Caspase-1 were markedly decreased (0.05) by diosgenin treatment. It also markedly ameliorated the histological insults induced in the colon by TNBS. In conclusion, diosgenin exerts its colon-protective efficacy probably through the inhibition of NF-κB/IkB-α and Bax/Caspase-1 signaling pathways to experimental TNBS-induced ulcerative colitis.

Abbreviations: ANOVA: Analysis of variance; 5-ASA: 5-aminosalicylic acid; Bax: Bcl-2-associated X protein; COX-2: Cyclooxygenase-2; DAI: Disease Activity Index; DMSO: Dimethyl sulfoxide; GAPDH: Glyceraldehyde 3-phosphate dehydrogenase; GSH: Glutathione; HP: Hydroxyproline; IAEC: International Animal Ethics Committee; IBD: Inflammatory Bowel Disease; IBS: Inflammatory Bowel Syndrome; IL's: Interleukin's; IFN-γ: Interferon-gamma; IκBα: nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor-alpha; iNOs: Inducible nitric oxide synthase; LTB4: Leukotriene B4; MDA: Malondialdehyde; MPO: Myeloperoxidase; NO: Nitric Oxide; NF-κB: Nuclear Factor-κB; ROS: Reactive Oxygen Species; SOD: Superoxide Dismutase; TNBS: Trinitrobenzene Sulfonic Acid; TNF-α: Tumor necrosis factor-α.
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http://dx.doi.org/10.1080/09168451.2020.1776590DOI Listing
September 2020

Changes in nutrient balance, environmental effects, and green development after returning farmland to forests: A case study in Ningxia, China.

Sci Total Environ 2020 Sep 14;735:139370. Epub 2020 May 14.

College of Resources and Environment, Northwest A&F University, 712100 Yangling, China. Electronic address:

Returning sloping farmland (>25°) to forest/grassland (RFTF) is an effective ecological measure for soil and water conservation. However, changes in nutrient cycles and green development are still unclear. Ningxia, in Northwestern China, began to implement RFTF in 2000. Here, we used the NUFER model to calculate the input and loss of nitrogen and phosphorus, utilization efficiency, production and consumption at food-chain scale in Ningxia for the period 1985-2015. Five aspects comprised the evaluation of green development: society, economy, resources, environment, and productivity. Results showed that forest coverage rate increased from 7.74% to 33.2%, while cropping area decreased by 6.6%. NH loss increased from 53,000 to 83,000 tons (56%), NO increased from 1200 to 2300 tons (92%) and leaching loss from 18,000 to 62,000 tons (240%). Phosphorus leaching loss increased from 13,000 to 35,000 tons (130%). The environmental cost of food nitrogen per unit of production decreased from 8 to 6.7 kg/kg (19.4%). Nitrogen and phosphorus use efficiencies decreased by 4.8% and 58% in crops-animal systems, respectively, but increased by 652% and 430% in animal husbandry systems. The proportion of animal protein production increased from 18.3% to 39.0% (113%). The major source of organic waste was livestock and poultry manure and urine (70%). Indicators for achieving green development level increased from 14 to 18 (14.7%). Improving the level of scientific and technological management of aquaculture system, increasing the proportion of organic matter returned to farmlands, and paying attention to the combination of planting and breeding will effectively promote future cycling efficiency of nitrogen and phosphorus in the food chain, and the sustainability of agriculture towards green development.
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http://dx.doi.org/10.1016/j.scitotenv.2020.139370DOI Listing
September 2020

The C-H Activation/Bidirecting Group Strategy for Selective Direct Synthesis of Diverse 1,1'-Biisoquinolines.

Org Lett 2020 Jun 19;22(11):4207-4212. Epub 2020 May 19.

Guangxi Key Laboratory of Electrochemical and Magneto-Chemical Function Materia, College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, China.

Multidentate ligands are highly important but difficult to access. Herein we disclose an atom- and step-economic synthesis of highly substituted 1,1'-biisoquinolines by a C-H activation/bididirecting group strategy. Through rational design of a bididirecting group to "N-OH + N-OAc", selective unsymmetrical diannulation with two different alkynes in a one-pot reaction has been achieved for the first time to access unsymmetrical biisoquinolines. Moreover, the resultant biisoquinolines show tunable photoluminescence and serve as aggregation-induced emission (AIE) systems.
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http://dx.doi.org/10.1021/acs.orglett.0c01260DOI Listing
June 2020

Broadband and high-efficiency spin-polarized wave engineering with PB metasurfaces.

Opt Express 2020 May;28(10):15601-15610

Manipulating circularly polarized (CP) light waves at will are highly important for photonic researches and applications. Recently, while Pancharatnam-Berry (PB) metasurfaces have shown unprecedented capabilities to control CP light, meta-devices constructed so far always suffer from the limitations of low-efficiency and narrow bandwidth. Here, we propose a scheme to construct PB metasurfaces with these two issues well addressed. To verify our idea, two PB meta-devices are designed and fabricated for achieving high-efficiency and broadband photonic spin Hall effect and focusing effect, respectively. Experimental results, in good agreement with full wave simulations, demonstrate the desired functionalities with efficiencies reaching 80% within an ultra-wide frequency band (8.2-17.3GHz). The proposed design scheme is generic and can be extended to high-frequency regimes. Our work can stimulate the realizations of high-performance and broadband PB meta-devices with diversified functionalities.
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http://dx.doi.org/10.1364/OE.394658DOI Listing
May 2020

Cytotoxic Free Radicals on Air-Borne Soot Particles Generated by Burning Wood or Low-Maturity Coals.

Environ Sci Technol 2020 05 3;54(9):5608-5618. Epub 2020 Mar 3.

Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.

The traditional cook stove is a major contributor to combustion-derived soot particles, which contain various chemical species that may cause a significant impact to human health and ecosystems. However, properties and toxicity associated with environmentally persistent free radicals (EPFRs) in such emissions are not well known. This paper investigated the characteristics and cytotoxicity of soot-associated EPFRs discharged from Chinese household stoves. Our results showed that the concentrations of EPFRs were related to fuel types, and they were higher in wood-burning soot (8.9-10.5 × 10 spins/g) than in coal-burning soot (3.9-9.7 × 10 spins/g). Meanwhile, EPFR concentrations in soot decreased with an increase of coal maturity. The soot EPFRs, especially reactive fractions, readily induced the generation of reactive oxygen species (ROS). Potential health effects of soot EPFRs were also examined using normal human bronchial epithelial cell line 16HBE as a model. Soot particles were internalized by 16HBE cells inducing cytotoxicity. The main toxicity inducers were identified to be reactive EPFR species, which generated ROS inside human cells. Our findings provided valuable insights into potential contributions of soot EPFRs associated with different types of fuel to health problems. This information will support regulations to end or limit current stove usage in numerous households.
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http://dx.doi.org/10.1021/acs.est.9b06395DOI Listing
May 2020

Soil C and N dynamics and hydrological processes in a maize-wheat rotation field subjected to different tillage and straw management practices.

Agric Ecosyst Environ 2019 Dec;285:106616

Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.

The impact of farmland nutrient losses on environment security is of serious concern. Conservation tillage led to reduced water and soil losses and increased grain yield, and is therefore one potential solution, but this approach requires an understanding of the complex adaptive traits for environment conditions. In this study, a 4-year field experiment was conducted to quantify the crop yield, runoff and soil water, organic C and N content dynamics in summer maize-winter wheat rations subjected to different tillage and straw management practices. Based on these, the effects of different tillage and straw management regimes on water, C and N balances of the soil-plant system was evaluated with a 11-year model prediction using the SPACSYS model. The treatments used in this study included conventional tillage (CT) with straw removal, conventional tillage with straw returning (CTSR), reduced tillage (RT) with straw removal and reduced tillage with straw returning (RTSR). The results showed that maize yield was remarkably affected by straw returning while there was no significant tillage effect. By contrast, wheat yield showed a high inter-annual variability, but was not significantly influenced by tillage and straw management practices. The soil water balance analysis demonstrated that the treatments with straw returning improved water use efficiency by increasing transpiration while reducing water losses through evaporation and runoff, compared to the straw-removal treatments. The simulations for all of the treatments showed that the soils acted as C and N sinks in the present study. Furthermore, plots that included straw returning amassed more C and N in the soil than the that with straw removal. Our work demonstrates that in maize-wheat rotation slopping land reduced tillage with straw returning is a win-win practice for the equilibrium between agricultural productivity and low soil water, C and N losses.
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http://dx.doi.org/10.1016/j.agee.2019.106616DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6743210PMC
December 2019

Effects of different mulching and fertilization on phosphorus transformation in upland farmland.

J Environ Manage 2020 Jan 23;253:109717. Epub 2019 Oct 23.

State Key Laboratory of Soil Erosion and Dry-land Farming on the Loess Plateau, Northwest A&F University, Yangling, 712100, China.

In the present study, the impact of different soil surface mulching, fertilization on phosphorus mineralization and bio-availability of spring maize at various growth stages and soil layers (0-20 and 20-40 cm soil layer) were evaluated. The results indicated that the contents of total P and Olsen-Phosphorus (Olsen-P) in the soils of 0-20 cm soil layer were significantly higher than those in the 20-40 cm soil layer at different stages. The addition of organic fertilizer significantly increased the soil total P and Olsen-P content in the 0-20 cm soil layer. The different surface mulching, no mulching (NM), gravel mulching (GM) and film mulching (FM) were significantly affected by the content of Olsen-P in both soil layers during the critical growth period of spring maize. The Ca-P contents in both soil layers were the maximum in terms of the inorganic phosphorus content in soils with different surface mulching and different fertilization. Surface mulching significantly affected the transformation of inorganic phosphorus in different soil layers of dry-land farmland, and accelerated the increase of Ca-P content (first phosphorus source) in 0-20 cm soil layer by GM and FM. In addition, phosphorus combined with inorganic nitrogen fertilizer increased Ca-P (second Olsen-P source) to a certain extent, and reduced the relative content of Ca-P (first phosphorus source). Compared with phosphate (P), nitrogen and phosphorus (NP) treatments, manure and nitrogen and phosphorus (MNP) treatments increased the contents of Ca-P (first phosphorus source) and Ca-P (second effective phosphorus source), while it reduced the insoluble phosphorus source (O-P) content.
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http://dx.doi.org/10.1016/j.jenvman.2019.109717DOI Listing
January 2020

Domino N-/C- or N-/N-/C-arylation of imidazoles to yield polyaryl imidazolium salts via atom-economical use of diaryliodonium salts.

Chem Commun (Camb) 2019 Sep;55(75):11267-11270

Guangxi Key Laboratory of Electrochemical and Magneto-Chemical Function Materia, College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, P. R. China.

Herein, we disclose a Cu-mediated domino di-/triarylation reaction of imidazoles to efficiently access polyaryl imidazolium salts in a single step by using two aryls as well as an anion of a diaryliodonium salt. The diarylation shows high atom economy and excellent selectivity with unsymmetrical iodonium salts.
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http://dx.doi.org/10.1039/c9cc05237bDOI Listing
September 2019

Solitary fibrous tumor in the subcutaneous soft tissues of the left abdominal wall: A case report.

Clin Case Rep 2019 Jul 4;7(7):1370-1373. Epub 2019 Jun 4.

Department of Gastrointestinal Surgery The First Affiliated Hospital of Bengbu Medical College Bengbu China.

Solitary fibrous tumor (SFT) derived from the abdominal wall is rare. We report a case of SFT in the abdominal wall. When abdominal computed tomography reveals soft-tissue mass and analysis of preoperative needle biopsy reveals spindle cell tumor, the possibility of SFT should be considered.
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http://dx.doi.org/10.1002/ccr3.2217DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6637379PMC
July 2019

The Adipokine Metrnl Ameliorates Chronic Colitis in Il-10-/- Mice by Attenuating Mesenteric Adipose Tissue Lesions During Spontaneous Colitis.

J Crohns Colitis 2019 Jul;13(7):931-941

Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu, Anhui.

Background: Crosstalk between mesenteric adipose tissue [MAT] and the intestines affects the progression of Crohn's disease [CD]. The adipokine metrnl regulates adipocyte function and has anti-inflammatory activity. We aimed to explore metrnl expression in CD MAT, investigate the influence of metrnl on the experimental colitis disease course and determine the mechanism underlying this effect.

Methods: Metrnl expression in MAT specimens obtained from patients with and without CD was tested by immunohistochemistry. Male Il-10-/- mice with spontaneous enteritis were divided into positive control and metrnl-treated [Metrnl-Fc, 10 mg/kg/d, intraperitoneally, 8 weeks] groups. Age-matched male wild-type [WT] mice were used as negative controls. The effects of metrnl on enteritis and mesenteric lesions and the potential controlling mechanisms were evaluated.

Results: Metrnl expression was higher in human CD MAT than in control MAT. Systemic delivery of metrnl significantly ameliorated chronic colitis in Il-10-/- mice, as demonstrated by decreases in the disease activity index, inflammatory score and proinflammatory mediators. The protective effects of metrnl on MAT included reduced mesenteric hypertrophy, increased adipocyte size, improved adipocyte intrinsic function and ameliorated inflammation. Metrnl treatment activated STAT5/PPAR-γ signaling and promoted adipocyte differentiation in the MAT.

Conclusions: Metrnl expression was increased in the MAT of CD patients. Metrnl administration attenuated mesenteric lesions by promoting adipocyte function and differentiation partly through STAT5/PPAR-γ signaling pathway activation, thereby ameliorating CD-like colitis in mice.
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http://dx.doi.org/10.1093/ecco-jcc/jjz001DOI Listing
July 2019

The tumor suppressor role of miR-155-5p in gastric cancer.

Oncol Lett 2018 Aug 8;16(2):2709-2714. Epub 2018 Jun 8.

Clinical Laboratory Department, The Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China.

Gastric cancer (GC) is the fifth most common type of malignant tumor worldwide and the most common cause of cancer-associated mortality in China. Recent studies revealed that microRNAs (miRNAs) function in the pathogenesis of GC, and that miR-155-5p expression is downregulated in GC tissues. However, the function of miR-155-5p has not been fully identified. In the present study, it was demonstrated that overexpression of miR-155-5p inhibited GC-cell proliferation and promoted apoptosis, while downregulation of miR-155-5p promoted GC-cell proliferation and decreased the cisplatin sensitivity of GC cells. Mitogen-activated protein kinase kinase kinase 10 was demonstrated to be a potential target gene of miR-155-5p. In conclusion, an antitumor role of miR-155-5p in gastric cancer was suggested.
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http://dx.doi.org/10.3892/ol.2018.8932DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6036547PMC
August 2018

Study on the potential way of hepatic cytotoxicity of N,N-dimethylformamide.

Authors:
Shiqing Li Cui Wang

J Biochem Mol Toxicol 2018 Sep 9;32(9):e22190. Epub 2018 Jul 9.

College of Life Science, Zhejiang Chinese Medical University, Hangzhou, 310053, China.

The intermediate metabolites and redox status imbalance were supported as the two major points for N,N-dimethylformamide (DMF)-induced hepatotoxicity. However, the potential mechanism has not yet been concerned. By applying two inhibitors, this study tried to seek the major role in DMF-induced toxicity on HL7702 cell. We observed that DMF induced cell apoptosis through mitochondrial-dependent and p53 pathway. Inhibition reactive oxygen species by catalase remarkably attenuated the mitochondrial transmembrane potential (MMP), apoptotic proteins, and apoptosis. On the contrary, it reduced the biodegradation rate of DMF by coincubation with CYP2E1 antagonist (DDC) partially reduced late apoptosis. However, the change in MMP, the ratio of Bax to Bcl-xl, and cleaved-caspase 9 was not attenuated by DDC. The pathway in DDC coincubation groups was related to the p53 rather than the mitochondrial pathway. Restoring the redox balance during biodegradation is much more effective than attenuating the metabolite rate of DMF. This study may provide a suitable prevention method to occupational workers.
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http://dx.doi.org/10.1002/jbt.22190DOI Listing
September 2018

Effects of water stress on water use efficiency of irrigated and rainfed wheat in the Loess Plateau, China.

Sci Total Environ 2018 Nov 14;642:1-11. Epub 2018 Jun 14.

State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling 712100, China; College of Resources and Environment, University of Chinese Academy of Science, Beijing 100049, China; School of Life Sciences, University of Technology Sydney, P.O. Box 123, Broadway, NSW 2007, Australia. Electronic address:

The Loess Plateau, the largest arid and semi-arid zone in China, has been confronted with more severe water resource pressure and a growing demand for food production under global changes. For developing sustainable agriculture in this region, it is critical to learn spatiotemporal variations in water use efficiency (WUE) of main crops (e.g. winter wheat in this region) under various water management practices. In this study, we classified irrigated and rainfed wheat areas based on MODIS data, and calculated the winter wheat yield by using an improved light use efficiency model. The actual evapotranspiration (ETa) of winter wheat and the evapotranspiration drought index (EDI) were also investigated. Then we mainly examined the synergistic relationship between crop yield, ETa, and WUE, and analyzed the variations in WUE of irrigated and rainfed wheat under water stress during the 2010-2011 growing season. The results suggested that winter wheat in the Loess Plateau was primarily dominated by rainfed wheat. The average yield of irrigated wheat was 3928.4 kg/ha, 22.2% more than that of rainfed wheat. High spatial heterogeneities of harvest index (HI) and maximum light use efficiency (ε) were found in the Loess Plateau. The ETa of irrigated wheat was 10.2% more than that of rainfed wheat. The ratio of irrigated and rainfed wheat under no water stress was 31.55% and 17.16%, respectively. With increasing water stress, the WUE of rainfed wheat decreased more quickly than that of irrigated wheat. The WUE variations in winter wheat under water stress depended strongly on the synergistic effects of two WUE components (crop yield and ETa) and their response to environmental conditions as well as water management practices (irrigated or rainfed). Our findings enhance our current understanding of the variations in WUE as affected by water stress under various water use conditions in arid and semi-arid areas.
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http://dx.doi.org/10.1016/j.scitotenv.2018.06.028DOI Listing
November 2018

Reveal the response of enzyme activities to heavy metals through in situ zymography.

Ecotoxicol Environ Saf 2018 Jul 14;156:106-115. Epub 2018 Mar 14.

College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling 712100, China.

Enzymes in the soil are vital for assessing heavy metal soil pollution. Although the presence of heavy metals is thought to change the soil enzyme system, the distribution of enzyme activities in heavy metal polluted-soil is still unknown. For the first time, using soil zymography, we analyzed the distribution of enzyme activities of alfalfa rhizosphere and soil surface in the metal-contaminated soil. The results showed that the growth of alfalfa was significantly inhibited, and an impact that was most pronounced in seedling biomass and chlorophyll content. Catalase activity (CAT) in alfalfa decreased with increasing heavy metal concentrations, while malondialdehyde (MDA) content continually increased. The distribution of enzyme activities showed that both phosphatase and β-glucosidase activities were associated with the roots and were rarely distributed throughout the soil. In addition, the total hotspot areas of enzyme activities were the highest in extremely heavy pollution soil. The hotspot areas of phosphatase were 3.4%, 1.5% and 7.1% under none, moderate and extremely heavy pollution treatment, respectively, but increased from 0.1% to 0.9% for β-glucosidase with the increasing pollution levels. Compared with the traditional method of enzyme activities, zymography can directly and accurately reflect the distribution and extent of enzyme activity in heavy metals polluted soil. The results provide an efficient research method for exploring the interaction between enzyme activities and plant rhizosphere.
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http://dx.doi.org/10.1016/j.ecoenv.2018.03.015DOI Listing
July 2018

Pursuing sustainable productivity with millions of smallholder farmers.

Nature 2018 03 7;555(7696):363-366. Epub 2018 Mar 7.

Institute of Agricultural Resources and Environment, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050051, China.

Sustainably feeding a growing population is a grand challenge, and one that is particularly difficult in regions that are dominated by smallholder farming. Despite local successes, mobilizing vast smallholder communities with science- and evidence-based management practices to simultaneously address production and pollution problems has been infeasible. Here we report the outcome of concerted efforts in engaging millions of Chinese smallholder farmers to adopt enhanced management practices for greater yield and environmental performance. First, we conducted field trials across China's major agroecological zones to develop locally applicable recommendations using a comprehensive decision-support program. Engaging farmers to adopt those recommendations involved the collaboration of a core network of 1,152 researchers with numerous extension agents and agribusiness personnel. From 2005 to 2015, about 20.9 million farmers in 452 counties adopted enhanced management practices in fields with a total of 37.7 million cumulative hectares over the years. Average yields (maize, rice and wheat) increased by 10.8-11.5%, generating a net grain output of 33 million tonnes (Mt). At the same time, application of nitrogen decreased by 14.7-18.1%, saving 1.2 Mt of nitrogen fertilizers. The increased grain output and decreased nitrogen fertilizer use were equivalent to US$12.2 billion. Estimated reactive nitrogen losses averaged 4.5-4.7 kg nitrogen per Megagram (Mg) with the intervention compared to 6.0-6.4 kg nitrogen per Mg without. Greenhouse gas emissions were 328 kg, 812 kg and 434 kg CO equivalent per Mg of maize, rice and wheat produced, respectively, compared to 422 kg, 941 kg and 549 kg CO equivalent per Mg without the intervention. On the basis of a large-scale survey (8.6 million farmer participants) and scenario analyses, we further demonstrate the potential impacts of implementing the enhanced management practices on China's food security and sustainability outlook.
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http://dx.doi.org/10.1038/nature25785DOI Listing
March 2018

Therapeutic effects of stemonine on particulate matter 2.5-induced chronic obstructive pulmonary disease in mice.

Exp Ther Med 2017 Nov 1;14(5):4453-4459. Epub 2017 Sep 1.

Center for Preventive Treatment of Disease, Yantai Hospital of Traditional Chinese Medicine, Yantai, Shandong 264016, P.R. China.

Particulate matter 2.5 (PM) is a growing concern worldwide due to its association with respiratory diseases, including chronic obstructive pulmonary disease (COPD). Stemonine, a traditional Chinese herb, has been demonstrated to exhibit anti-inflammatory and antioxidant properties, making it a potential drug for the treatment of respiratory diseases. The therapeutic effects of stemonine on mice with PM-induced COPD were investigated in the present study. Kunming mice were randomly divided into the following five groups (n=10/group): Control, model, low-dose stemonine, moderate-dose stemonine and high-dose stemonine. The model mice received an intranasal instillation of PM suspension (40 mg/kg). The levels of specific enzymes, markers of oxidative stress, and the inflammatory cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6 were measured in the bronchoalveolar lavage fluid of the mice using ELISA kits. Hematoxylin and eosin staining was performed to determine inflammatory changes to the lung tissue. It was demonstrated that stemonine could significantly alleviate lung injury by decreasing the levels of enzymes and cytokines associated with inflammation and oxidative stress in a dose-dependent manner. In addition, stemonine dose-dependently increased the amount of superoxide dismutase. These results suggest that stemonine reduces lung inflammation in mice with PM-induced COPD, providing a novel approach for the treatment of PM-induced respiratory diseases.
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http://dx.doi.org/10.3892/etm.2017.5092DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5658775PMC
November 2017

High-Performance Ruthenium Sensitizers Containing Imidazolium Counterions for Efficient Dye Sensitization in Water.

ChemSusChem 2017 07 21;10(14):2914-2921. Epub 2017 Jun 21.

Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, PR China.

A new type of water-soluble ruthenium sensitizers incorporating imidazolium counterions, denoted [DMPI] -Ru and [DMHI] -Ru, has been developed, which can be efficiently adsorbed onto TiO photoanodes in aqueous solution. Owing to the good thermal stability of imidazolium, [DMPI] -Ru adsorbed on TiO has a higher decomposition temperature than N719 dye [di(tetrabutylammonium) cis-di(thiocyanato)bis(2,2'-bipyridine-4,4'-dicarboxylato)ruthenium(II)]. When using organic solvent-based I /I electrolytes, solars cell based on [DMPI] -Ru-sensitized TiO in water show high power conversion efficiencies (PCE) of up to 10.2 %, which is higher than that of N719 (9.9 %) under the common conditions for dye sensitization in organic solvent. [DMHI] -Ru, with poorer water solubility than [DMPI] -Ru, gives a smaller dye-adsorption amount on TiO and thus a lower PCE of 9.4 %. From the viewpoint of safety and environmental impact, the fabrication of dye-sensitized solar cells (DSSCs) by using water as solvent is undoubtedly a preferable strategy. Although the [DMPI] -Ru-based device fabricated by using water as the solvent for both the dye-sensitization process and the electrolyte gives a relatively low efficiency, it provides a promising approach for the practical application of DSSCs.
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http://dx.doi.org/10.1002/cssc.201700579DOI Listing
July 2017

Cu-catalyzed controllable C-H mono-/di-/triarylations of imidazolium salts for ionic functional materials.

Chem Commun (Camb) 2017 Mar 10;53(24):3489-3492. Epub 2017 Mar 10.

Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu 610064, P. R. China.

Herein the Cu-catalyzed direct C-H mono-, di- and triarylations of imidazolium salts with aryl iodides/bromides are accomplished for the first time. The unprecedented alkenylation and alkynylation are also realized using alkenyl and alkynyl iodides, respectively. Moreover, triarylated imidazolium salts with different substituents can be accessed in a modular and one-pot manner. This protocol provides an efficient tool for the assembly of diverse imidazolium-based ionic functional materials. As applicable examples, an electrochromic bisbenzimidazolium salt 7 and a photochromic triarylimidazolium salt 8 are easily obtained.
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http://dx.doi.org/10.1039/c7cc01076aDOI Listing
March 2017

Rh/Cu-Catalyzed Cascade [4+2] Vinylic C-H O-Annulation and Ring Contraction of α-Aryl Enones with Alkynes in Air.

Angew Chem Int Ed Engl 2017 04 9;56(15):4286-4289. Epub 2017 Mar 9.

Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P.R. China.

An unprecedented Rh-catalyzed ketone-directed vinylic C-H activation/[4+2] O-annulation of α-aryl enones with internal alkynes followed by a Cu-catalyzed ring contraction in air to provide multiaryl-substituted furan derivatives has been developed. The preliminary mechanism study identifies the active pyrylium salt as the key intermediate.
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http://dx.doi.org/10.1002/anie.201612147DOI Listing
April 2017

Cascade C-H Annulation of Aldoximes with Alkynes Using O as the Sole Oxidant: One-Pot Access to Multisubstituted Protoberberine Skeletons.

Org Lett 2017 02 19;19(3):604-607. Epub 2017 Jan 19.

Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University , 29 Wangjiang Road, Chengdu 610064, P.R. China.

A cascade double C-H annulation of aldoximes with alkynes to produce benz[a]acridizinium salts is developed by using a simple catalytic system of [Cp*Rh(OAc)] in the presence of Zn(OTf) with oxygen as the sole oxidant. In addition, the challenging C-H annulation of aldoximes with alkynes, especially arylalkynes, to synthesize 1H-isoquinolines is also achieved under slightly modified conditions. This protocol provides an efficient one-pot access to multisubstituted dehydroberberinium skeletons from simple starting materials, which can be easily transformed into berberinium and tetrahydroberberine skeletons by controlled hydrogenation.
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http://dx.doi.org/10.1021/acs.orglett.6b03772DOI Listing
February 2017

Room-Temperature Coupling/Decarboxylation Reaction of α-Oxocarboxylates with α-Bromoketones: Solvent-Controlled Regioselectivity for 1,2- and 1,3-Diketones.

J Org Chem 2017 02 18;82(3):1403-1411. Epub 2017 Jan 18.

Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University 29 Wangjiang Road, Chengdu 610064, P. R. China.

A transition-metal-free and room-temperature coupling/decarboxylation reaction between α-oxocarboxylates and α-bromoketones is reported herein. It represents the first mild and regioselective synthesis of either 1,2- or 1,3-diketones from the same starting materials. Notably, the regioselectivity is simply controlled by solvents. The preliminary experimental data and DFT calculations suggest sequential Darzens-type coupling, alkaline hydrolysis, KOH-promoted oxirane opening and decarboxylation in one pot. This method is efficient for the synthesis of α,β-epoxy-γ-butyrolactone and curcuminoids.
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http://dx.doi.org/10.1021/acs.joc.6b02575DOI Listing
February 2017

Microbial Functional Diversity, Biomass and Activity as Affected by Soil Surface Mulching in a Semiarid Farmland.

PLoS One 2016 14;11(7):e0159144. Epub 2016 Jul 14.

State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Northwest A&F University, Yangling 712100, Shaanxi, China.

Mulching is widely used to increase crop yield in semiarid regions in northwestern China, but little is known about the effect of different mulching systems on the microbial properties of the soil, which play an important role in agroecosystemic functioning and nutrient cycling. Based on a 4-year spring maize (Zea mays L.) field experiment at Changwu Agricultural and Ecological Experimental Station, Shaanxi, we evaluated the responses of soil microbial activity and crop to various management systems. The treatments were NMC (no mulching with inorganic N fertilizer), GMC (gravel mulching with inorganic N fertilizer), FMC (plastic-film mulching with inorganic N fertilizer) and FMO (plastic-film mulching with inorganic N fertilizer and organic manure addition). The results showed that the FMO soil had the highest contents of microbial biomass carbon and nitrogen, dehydrogenase activity, microbial activity and Shannon diversity index. The relative use of carbohydrates and amino acids by microbes was highest in the FMO soil, whereas the relative use of polymers, phenolic compounds and amines was highest in the soil in the NMC soil. Compared with the NMC, an increased but no significant trend of biomass production and nitrogen accumulation was observed under the GMC treatment. The FMC and FMO led a greater increase in biomass production than GMC and NMC. Compare with the NMC treatment, FMC increased grain yield, maize biomass and nitrogen accumulation by 62.2, 62.9 and 86.2%, but no significant difference was found between the FMO and FMC treatments. Some soil biological properties, i.e. microbial biomass carbon, microbial biomass nitrogen, being sensitive to the mulching and organic fertilizer, were significant correlated with yield and nitrogen availability. Film mulching over gravel mulching can serve as an effective measure for crop production and nutrient cycling, and plus organic fertilization additions may thus have improvements in the biological quality of the soil and its sustainability in the rainfall-limited semiarid region.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0159144PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4945083PMC
July 2017
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