Publications by authors named "Dayong Zhang"

102 Publications

Protective effect of berberine against LPS-induced endothelial cell injury via the JNK signaling pathway and autophagic mechanisms.

Bioengineered 2021 Dec;12(1):1324-1337

Department of Emergency Medicine, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.

The role of autophagic mechanisms in the protective effect of berberine (BBR) on lipopolysaccharide (LPS)-induced injury in the endothelial cells human umbilical vein endothelial cells (HUVECs) and human pulmonary microvascular endothelial cells (HPMECs) was investigated. Cell viability, proliferation, and apoptosis were detected by the CCK-8 assay, the EdU kit, and flow cytometry, respectively, and autophagy-related protein expression, the number of autophagic vacuoles, and LC3 double-fluorescence were examined using western blot analysis, transmission electron microscopy, and confocal microscopy, respectively. LPS resulted in a decrease in the cell viability and proliferation of HUVECs and HPMECs and an increase in the number of apoptotic cells, while BBR treatment resulted in an increase in cell viability and proliferation, as well as a decrease in cell apoptosis. Furthermore, BBR could inhibit LPS-induced autophagy, as demonstrated by its inhibitory effects on the LC3-II/LC3-I ratio and Beclin-1 levels and its promotive effect on p62 expression. Addition of the autophagy inducer rapamycin (RAPA) aggravated LPS-induced injury, while treatment with the autophagy blocker 3-methyladenine (3-MA) attenuated the injury. Further, the protective effect of BBR was inhibited by rapamycin. JNK inhibition by SP600125 inhibited LPS-induced autophagy, and BBR could not alter the LPS-induced autophagy in HUVECs and HPMECs that were pretreated with SP600125. The present data indicate that BBR attenuated LPS-induced cell apoptosis by blocking JNK-mediated autophagy in HUVECs and HPMECs. Therefore, the JNK-mediated autophagy pathway could be a potential target for the prevention and treatment of cardiovascular disease.
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http://dx.doi.org/10.1080/21655979.2021.1915671DOI Listing
December 2021

Reducing Metal/Graphene Contact Resistance via N, N-Dimethylacetamide-Assisted Clean Fabrication Process.

Nanotechnology 2021 Apr 21. Epub 2021 Apr 21.

Institute of Microelectronics Chinese Academy of Sciences, Beijing, CHINA.

Contact resistance (R) is of great importance for radio frequency (RF) applications of graphene, especially graphene field effect transistors (FETs) with short channel. FETs and transmission line model (TLM) test structures based on chemical vapor deposition grown graphene are fabricated. The effects of employing traditional lithography solvent (Acetone) and strong solvents for photo resist, such as N, N-Dimethylacetamide (ZDMAC) and N-Methyl pyrrolidone (NMP), are systematically investigated. It was found that ZDMAC and NMP have more proficiency than acetone to remove the photo-resist residues and contaminations attached on graphene surface, enabling clean surface of graphene. However, strong solvents are found to destroy the lattice structure of graphene channel and induce defects in graphene lattice. Clean surface contributes to a significant reduction in the Rbetween graphene channel and metal electrode, and the defects introduced on graphene surface underneath metal electrodes also contribute the reduction of R. But defects and deformation of lattice will increase the resistance in graphene channel and lead to the compromise of device performance. To address this problem, a mix wet-chemical approach employing both acetone and ZDMAC was developed in our study to realize a 19.07% reduction of R, without an unacceptable mass production of defects.
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http://dx.doi.org/10.1088/1361-6528/abfa56DOI Listing
April 2021

Low host specificity and broad geographical ranges in a community of parasitic non-pollinating fig wasps (Sycoryctinae; Chalcidoidea).

J Anim Ecol 2021 Mar 18. Epub 2021 Mar 18.

Agriculture and Environment Department, Harper Adams University, Newport, UK.

Plants, phytophagous insects and their parasitoids form the most diverse assemblages of macroscopic organisms on earth. Enclosed assemblages in particular represent a tractable system for studying community assembly and diversification. Communities associated with widespread plant species are especially suitable as they facilitate a comparative approach. Pantropical fig-wasp communities represent a remarkably well-replicated system, ideal for studying these historical processes. We expect high dispersal ability in non-pollinating fig wasps to result in lower geographical turnover in comparison to pollinating fig wasps. The ability of non-pollinating wasps to utilise a number of hosts (low host specificity) is a key determinant of overall geographical range, with intraspecific competition becoming a constraining factor should diet breadth overlap among species. Finally, we expect conserved community structure throughout the host range. We aim to test these expectations, derived from population genetic and community studies, using the multi-trophic insect community associated with Ficus hirta throughout its 3,500 km range across continental and insular Asia. We collect molecular evidence from one coding mitochondrial gene, one non-coding nuclear gene and multiple microsatellites across 25 geographical sites. Using these data, we establish species boundaries, determine levels of host specificity among non-pollinating fig wasps and quantify geographical variation in community composition. We find low host specificity in two genera of non-pollinating fig wasps. Functional community structure is largely conserved across the range of the host fig, despite limited correspondence between the ranges of non-pollinator and pollinator species. While nine pollinators are associated with Ficus hirta, the two non-pollinator tribes developing in its figs each contained only four species. Contrary to predictions, we find stronger isolation by distance in non-pollinators than pollinators. Long-lived non-pollinators may disperse more gradually and be less reliant on infrequent long-distance dispersal by wind currents. Segregation among non-pollinating species across their range is suggestive of competitive exclusion and we propose that this may be a result of increased levels of local adaptation and moderate, but regular, rates of dispersal. Our findings provide one more example of lack of strict codiversification in the geographical diversification of plant-associated insect communities.
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http://dx.doi.org/10.1111/1365-2656.13483DOI Listing
March 2021

Cotton Fiber Development Requires the Pentatricopeptide Repeat Protein GhIm for Splicing of Mitochondrial nad7 mRNA.

Genetics 2021 Mar;217(1):1-17

State Key Laboratory of Crop Genetics & Germplasm Enhancement, Hybrid Cotton R & D Engineering Research Center, Ministry of Education, Nanjing Agricultural University, Nanjing 210095, China.

Pentatricopeptide repeat (PPR) proteins encoded by nuclear genomes can bind to organellar RNA and are involved in the regulation of RNA metabolism. However, the functions of many PPR proteins remain unknown in plants, especially in polyploidy crops. Here, through a map-based cloning strategy and Clustered regularly interspaced short palindromic repeats/cas9 (CRISPR/cas9) gene editing technology, we cloned and verified an allotetraploid cotton immature fiber (im) mutant gene (GhImA) encoding a PPR protein in chromosome A03, that is associated with the non-fluffy fiber phenotype. GhImA protein targeted mitochondrion and could bind to mitochondrial nad7 mRNA, which encodes the NAD7 subunit of Complex I. GhImA and its homolog GhImD had the same function and were dosage-dependent. GhImA in the im mutant was a null allele with a 22 bp deletion in the coding region. Null GhImA resulted in the insufficient GhIm dosage, affected mitochondrial nad7 pre-mRNA splicing, produced less mature nad7 transcripts, and eventually reduced Complex I activities, up-regulated alternative oxidase metabolism, caused reactive oxygen species (ROS) burst and activation of stress or hormone response processes. This study indicates that the GhIm protein participates in mitochondrial nad7 splicing, affects respiratory metabolism, and further regulates cotton fiber development via ATP supply and ROS balance.
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http://dx.doi.org/10.1093/genetics/iyaa017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8045684PMC
March 2021

Silver-catalyzed synthesis of β-fluorovinylphosphonates by phosphonofluorination of aromatic alkynes.

Beilstein J Org Chem 2020 18;16:3086-3092. Epub 2020 Dec 18.

School of Science, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210000, P. R. China.

A silver-catalyzed three-component reaction involving alkynes, Selectfluor, and diethyl phosphite was employed for the one-pot formation of C(sp)-F and C(sp)-P bonds to provide an efficient access to β-fluorovinylphosphonates in a highly regio- and stereoselective manner under mild reaction conditions. This reaction is operationally simple and offers an excellent functional group tolerance as well as a broad substrate scope that includes both terminal and internal alkynes. The reaction proceeded through the oxidative generation of a P-centered radical and subsequent fluorine atom transfer.
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http://dx.doi.org/10.3762/bjoc.16.258DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7753110PMC
December 2020

Stable P-Type chemical doping of graphene with reduced contact resistance by a single layer PFSA.

Nanotechnology 2020 Dec 28. Epub 2020 Dec 28.

Institute of Microelectronics Chinese Academy of Sciences, Beijing, CHINA.

Recently, graphene has provided unprecedent progress in device performance at the atom limit. High performance of field-effect transistors (FETs) requires a low graphene-metal contact resistance. However, the chemical doping methods used to tailor or improve the properties of graphene are sensitive to ambient conditions. Here, we fabricate a single layer perfluorinated polymeric sulfonic acid (PFSA), also known as Nafion, between graphene and the substrate as a p-type dopant. The PFSA doping method, without inducing any additional structural defects, reduces the contact resistance of graphene by ~28.8%, which has a significant impact on practical applications. This reduction can keep at least 67 days due to the extreme stability of PFSA. Effective, uniform and stable, the PFSA doping method provides an efficient way to reduce the contact resistance of graphene applications.
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http://dx.doi.org/10.1088/1361-6528/abd715DOI Listing
December 2020

Structure-guided modification of isoxazole-type FXR agonists: Identification of a potent and orally bioavailable FXR modulator.

Eur J Med Chem 2021 Jan 7;209:112910. Epub 2020 Oct 7.

State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China. Electronic address:

Farnesoid X receptor (FXR) agonists are emerging as potential therapeutics for the treatment of various metabolic diseases, as they display multiple effects on bile acid, lipid, and glucose homeostasis. Although the steroidal obeticholic acid, a full FXR agonist, was recently approved, several side effects probably due to insufficient pharmacological selectivity impede its further clinical application. Activating FXR in a partial manner is therefore crucial in the development of novel FXR modulators. Our efforts focusing on isoxazole-type FXR agonists, common nonsteroidal agonists for FXR, led to the discovery a series of novel FXR agonists bearing aryl urea moieties through structural simplification of LJN452 (phase 2). Encouragingly, compound 11k was discovered as a potent FXR agonist which exhibited similar FXR agonism potency but lower maximum efficacy compared to full agonists GW4064 and LJN452 in cell-based FXR transactivation assay. Extensive in vitro evaluation further confirmed partial efficacy of 11k in cellular FXR-dependent gene modulation, and revealed its lipid-reducing activity. More importantly, orally administration of 11k in mice exhibited desirable pharmacokinetic characters resulting in promising in vivo FXR agonistic activity.
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http://dx.doi.org/10.1016/j.ejmech.2020.112910DOI Listing
January 2021

Ferroptosis involves in renal tubular cell death in diabetic nephropathy.

Eur J Pharmacol 2020 Dec 22;888:173574. Epub 2020 Sep 22.

School of Sciences, China Pharmaceutical University, Nanjing, 211198, China. Electronic address:

Ferroptosis is a novel type of programmed cell death characterized by iron-dependent accumulation of lipid hydroperoxides to lethal levels. Accumulative studies have indicated diabetic nephropathy (DN) as an inflammatory disorder, which involved immune modulation both in the occurrence and progression of the disease. In addition, DN is also considered as the major threatening complication of Diabetes mellitus (DM). However, other forms of programmed cell death, such as autophagy, apoptosis and necrosis, have been reported to be associated with DN, while there are no effective drugs to alleviate the damage of DN. In this study, we explored whether ferroptosis was involved in the progression of DN both in vivo and in vitro. We first established DN models using streptozotocin (STZ) and db/db mice. Results showed significant changes of ferroptosis associated markers, like increased expression levels of acyl-CoA synthetase long-chain family member 4 (ACSL4) and decreased expression levels of glutathione peroxidase 4 (GPX4) in DN mice. Also lipid peroxidation products and iron content were increased in DN mice. Next, in vitro, ferroptosis inducer erastin or RSL3 could induce renal tubular cell death, while iron and high ACSL4 levels sensitised ferroptosis. Finally, ACSL4 inhibitor rosiglitazone (Rosi) was used in the development of DN, which improved survival rate and kidney function, reduced lipid peroxidation product MDA and iron content. In summary, we first found ferroptosis was involved in DN and ferroptosis might be as a future direction in the treatment of DN.
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http://dx.doi.org/10.1016/j.ejphar.2020.173574DOI Listing
December 2020

Extreme risk spillover between chinese and global crude oil futures.

Financ Res Lett 2020 Aug 30:101743. Epub 2020 Aug 30.

Institutes of Science and Development, Chinese Academy of Sciences, Beijing 100190, China.

This paper investigates the risk spillover between China's crude oil futures and international crude oil futures by constructing upside and downside VaR connectedness networks. The findings show that China's crude oil futures behave as a net risk receiver in the global crude oil system, in which Brent and WTI play the leading roles in risk transmission in the system. The dynamic results indicate that the risk spillover between Chinese and international crude oil futures presents obvious time-varying characteristics and has risen sharply since the beginning of 2020, induced by the COVID-19 pandemic.
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http://dx.doi.org/10.1016/j.frl.2020.101743DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7456448PMC
August 2020

Increasing vaccination coverage: The school entry vaccination record check program in Guizhou Province China, 2003-2018.

Vaccine 2020 10 3;38(46):7379-7383. Epub 2020 Sep 3.

Office of the WHO Western Pacific Region, Manila, Philippines.

Background: Guizhou Province of China implements a vaccination program specifying that children's vaccination records are to be checked upon entry to kindergarten and primary school; children missing one or more recommended vaccinations are to be offered the missed vaccinations; school-level vaccination coverage levels are assessed at the time of school enrollment and six months later to monitor compliance rates.

Methods: We obtained the number of doses of each vaccine in the national immunization schedule that were administered before and six months after kindergarten and school enrollment and reported to Guizhou Province during 2004 through 2018. We determined temporal trends in coverage of the second dose of measles-containing vaccine (MCV2) and other vaccines, incidence of measles, and number of school-based measles outbreaks.

Results: MCV2 coverage at kindergarten entry increased from 53% in 2004 to 98% in 2018. Among children missing one or more vaccinations, the six-month catch-up rate of MCV2 increased from 80% in 2004 to 99% in 2018. Among primary school children, coverage of MCV2 and other recommended vaccines had similar increases. The annual incidence of measles among Guizhou's total population declined from 280 per million in 2003 to 0.3 per million in 2018. There have been no measles outbreaks in kindergartens or schools since 2015.

Conclusions: Checking vaccination record at kindergartens and primary schools and providing necessary catch-up vaccination was associated with increased coverage of measles and other vaccines, lower incidence of measles, and an apparent end to school-based measles outbreaks. Guizhou's experience of checking vaccination records at school enrollment led to implementation of this strategy in other provinces. In 2019, the kindergarten and school entry vaccination record check program was incorporated into China's national vaccine law.
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http://dx.doi.org/10.1016/j.vaccine.2020.08.055DOI Listing
October 2020

Financial markets under the global pandemic of COVID-19.

Financ Res Lett 2020 Oct 16;36:101528. Epub 2020 Apr 16.

Institute of Science and Development, Chinese Academy of Sciences, Beijing 100190, China.

The rapid spread of coronavirus (COVID-19) has dramatic impacts on financial markets all over the world. It has created an unprecedented level of risk, causing investors to suffer significant loses in a very short period of time. This paper aims to map the general patterns of country-specific risks and systemic risks in the global financial markets. It also analyses the potential consequence of policy interventions, such as the US' decision to implement a zero-percent interest rate and unlimited quantitative easing (QE), and to what extent these policies may introduce further uncertainties into global financial markets.
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http://dx.doi.org/10.1016/j.frl.2020.101528DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7160643PMC
October 2020

Effects of Charge Trapping at the MoS-SiO Interface on the Stability of Subthreshold Swing of MoS Field Effect Transistors.

Materials (Basel) 2020 Jun 28;13(13). Epub 2020 Jun 28.

High-Frequency High-Voltage Device and Integrated Circuits R&D Center, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, China.

The stability of the subthreshold swing (SS) is quite important for switch and memory applications in logic circuits. The SS in our MoS field effect transistor (FET) is enlarged when the gate voltage sweep range expands towards the negative direction. This is quite different from other reported MoS FETs whose SS is almost constant while varying gate voltage sweep range. This anomalous SS enlargement can be attributed to interface states at the MoS-SiO interface. Moreover, a deviation of SS from its linear relationship with temperature is found. We relate this deviation to two main reasons, the energetic distribution of interface states and Fermi level shift originated from the thermal activation. Our study may be helpful for the future modification of the MoS FET that is applied in the low power consumption devices and circuits.
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http://dx.doi.org/10.3390/ma13132896DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7372460PMC
June 2020

Cu-Photoredox-catalyzed C(sp)-C(sp) coupling of redox-active esters with terminal alkynes.

Org Biomol Chem 2020 Jun 3. Epub 2020 Jun 3.

School of Science, China Pharmaceutical University, Nanjing 210009, P.R. China.

Visible-light-induced C(sp)-C(sp3) coupling of redox-active esters with terminal alkynes has been developed. The activation of carboxylic acids as their redox-active ester derivatives was important for this decarboxylative alkynylation. The strategy established here facilitates the straightforward introduction of triple-bonded functional groups and avoids additional photocatalysts. A wide range of primary, secondary and tertiary acids can be converted into the target products; so this reaction exhibits a broad substrate scope and tolerance of functional groups. Mechanistic experiments suggested that this reaction may undergo a radical process. Under mild reaction conditions, a copper acetylide ligand as a photocatalyst delivered an electron to redox-active ester derivatives, and generated alkyl radicals. The radicals reacted with Cu(ii) to deliver a Cu(iii) complex, and then reductive elimination gave the products.
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http://dx.doi.org/10.1039/d0ob00835dDOI Listing
June 2020

Chinese expert brief consensus on newborn screening of inherited metabolic disorders during the novel coronavirus infection epidemic.

Ann Transl Med 2020 Apr;8(7):429

Newborn Screening Center/Center for Clinical Molecular Laboratory Medicine, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, China.

Novel coronavirus (2019-nCov) infection (COVID-19) rapidly spread across China and 25 countries in the worldwide, which infected not only adults but also children, even neonates. Each year, about 15 million newborns are delivered in China. Newborn screening (NBS) helps effectively prevent some mental retardation, premature death, and adverse outcomes in the early stage of baby, which could detect some inherited metabolic disorders (IMDs). During this COVID-19 epidemic, how to balance the risk of infected 2019-nCov and the risk of disability and teratogenesis of IMDs. Expert members of NBS extra quality assessment in National Clinical Center of Laboratory (NCCL) give a brief consensus for NBS of IMDs in the COVID-2019 epidemic, hoping that the brief consensus could be reference for NBS of IMDs in the other epidemic areas or periods all over the world.
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http://dx.doi.org/10.21037/atm.2020.03.60DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7210144PMC
April 2020

Visible-Light-Induced Copper-Catalyzed Alkynylation/Alkylation of Alkenes.

J Org Chem 2020 Mar 27;85(5):3213-3223. Epub 2020 Feb 27.

School of Science, China Pharmaceutical University, Nanjing 210009, P. R. China.

A photoinduced, copper-catalyzed, three-component reaction of haloalkane, alkenes, and alkyne under mild reaction conditions is reported. The reaction provides a direct approach to introducing privileged functionalities into propargylic systems.
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http://dx.doi.org/10.1021/acs.joc.9b03087DOI Listing
March 2020

Design, synthesis, and pharmacological evaluation of 4- or 6-phenyl-pyrimidine derivatives as novel and selective Janus kinase 3 inhibitors.

Eur J Med Chem 2020 Apr 16;191:112148. Epub 2020 Feb 16.

Institute of Pharmaceutical Science, China Pharmaceutical University, Nanjing, 210009, PR China. Electronic address:

As non-receptor tyrosine kinases, Janus kinases (JAKs) have become an attractive target for the treatment of autoimmune diseases and cancers. JAKs play a pivotal role in innate immunity, inflammation, and hematopoiesis by mediating the signaling of numerous cytokines, growth factors, and interferons (IFNs). Selective inhibitors of a variety of JAK members are expected to inhibit pro-inflammatory cytokine-mediated inflammation and immune responses, while preventing targeting other subtypes of JAKs. In this work, poorly selective compounds based on 4- or 6-phenyl-pyrimidine derivatives have been improved to highly potent and selective compounds by designing a covalent binding tether, which attaches to the unique cysteine (Cys909) residue in JAK3. Compound 12 exhibited potent JAK3 inhibitory activity (IC = 1.7 nM) with an excellent selectivity profile when compared to the other JAK isoforms (>588-fold). In a cellular assay, compound 12 strongly inhibited JAK3-dependent signaling and T cell proliferation. Moreover, in vivo data revealed that compound 12 significantly suppressed oxazolone (OXZ)-induced delayed hypersensitivity responses in Balb/c mice. Compound 12 also displayed decent pharmacokinetic properties and was suitable for in vivo use. Taken together, these results indicated that compound 12 may be a promising tool compound as a selective JAK3 inhibitor for treating autoimmune diseases.
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http://dx.doi.org/10.1016/j.ejmech.2020.112148DOI Listing
April 2020

Regulation of Ammonium Cellular Levels is An Important Adaptive Trait for the Euhalophytic Behavior of Salicornia europaea.

Plants (Basel) 2020 Feb 17;9(2). Epub 2020 Feb 17.

College of Life Sciences and Engineering, Southwest University of Sciences and Technology, Mianyang 62101, China.

Salinization of agricultural land is a devastating phenomenon which will affect future food security. Understanding how plants survive and thrive in response to salinity is therefore critical to potentiate tolerance traits in crop species. The halophyte has been used as model system for this purpose. High salinity causes NH accumulation in plant tissues and consequent toxicity symptoms that may further exacerbate those caused by NaCl. In this experiment we exposed Salicornia plants to five concentrations of NaCl (0, 1, 10, 50 and 200 mM) in combination with two concentrations of NHCl (1 and 50 mM). We confirmed the euhalophytic behavior of Salicornia that grew better at 200 vs. 0 mM NaCl in terms of both fresh (+34%) and dry (+46%) weights. Addition of 50 mM NHCl to the growth medium caused a general growth reduction, which was likely caused by NH accumulation and toxicity in roots and shoots. When plants were exposed to high NHCl, high salinity reduced roots NH concentration (-50%) compared to 0 mM NaCl. This correlates with the activation of the NH assimilation enzymes, glutamine synthetase and glutamate dehydrogenase, and the growth inhibition was partially recovered. We argue that NH detoxification is an important trait under high salinity that may differentiate halophytes from glycophytes and we present a possible model for NH detoxification in response to salinity.
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http://dx.doi.org/10.3390/plants9020257DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7076498PMC
February 2020

Copper-Catalyzed Photoinduced Enantioselective Dual Carbofunctionalization of Alkenes.

Org Lett 2020 Feb 6;22(4):1490-1494. Epub 2020 Feb 6.

State Key Laboratory of Organometallic Chemistry , Shanghai Institute of Organic Chemistry, Center for Excellence in Molecular Synthesis, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , P. R. China.

A photoinduced, copper-catalyzed, highly enantioselective dual alkylation/arylation and alkynylation of alkene is reported. A single chiral copper(I) complex serves to enable photoredox catalysis and induce enantioselectivity during the reaction. This reaction couples three different components under mild reaction conditions, exhibits a broad substrate scope, and provides facile access to chiral propargylic systems, including those featuring valuable fluorinated substituents.
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http://dx.doi.org/10.1021/acs.orglett.0c00071DOI Listing
February 2020

[Effects of resveratrol on aging of mesenchymal stem cells and its mechanism].

Zhejiang Da Xue Xue Bao Yi Xue Ban 2019 Dec;48(6):617-624

School of Medicine, Zhejiang University City College, Hangzhou 310015, China.

Objective: To investigate the effects of resveratrol (Res) on aging of marrow mesenchymal stem cells (MSCs), and to explore its mechanism.

Methods: MSCs were isolated from young SD rats and cultured . The optimal D-gal concentration for induction of MSCs senescence was determined. Then MSCs were randomly divided into four groups, namely the control group, 10μmol/L, 50μmol/L and 100μmol/L Res groups. After the cells were treated with different concentration of Res for 48 h, the senescence-associated changes were examined with senescence-associated-β-galactosidase (SA-β-gal) staining; the expression of p53, p16 and γ-H2AX was evaluated by Western blot. The total active oxygen species (ROS) level was determined by flow cytometry with DCFH-DA staining. In order to assess the effect of Res on the mitochondrial function, MitoSox Red staining was used to detect mitochondrial ROS levels in each group, mitochondrial membrane potential was detected by JC-1 assay, mPTP method was used to detect mitochondrial membrane channel opening level, and Western blot was used to detect the expression level of cytoplasmic cytochrome C (Cyt-C).

Results: D-gal 10 and 50 g/L significantly increased the number of SA-β-gal positive cells and the level of mitochondrial ROS (all <0.01). Therefore, 10 g/L D-gal was used to induce the senescence of MSCs in subsequent experiment. Compared with the control group, the number of SA-β-gal positive cells in Res groups significantly decreased (all <0.01), the expression of p53, p16 and γ-H2AX decreased, and the total and mitochondrial ROS level also decreased (all <0.01). Moreover, mitochondrial membrane potential, open level of mitochondrial membrane channels and the levels of cytoplasm Cyt-C in the Res treatment groups decreased compared with the control group (<0.05 or <0.01).

Conclusions: Resveratrol can protect the mitochondrial function of MSCs, and effectively delay the MSC senescence.
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December 2019

Genome-wide association reveals genetic variation of lint yield components under salty field conditions in cotton (Gossypium hirsutum L.).

BMC Plant Biol 2020 Jan 14;20(1):23. Epub 2020 Jan 14.

State Key Laboratory of Crop Genetics and Germplasm Enhancement, Engineering Research Center of Hybrid Cotton Development (the Ministry of Education), Nanjing Agricultural University, Nanjing, 210095, China.

Background: Salinity is one of the most significant environmental factors limiting the productivity of cotton. However, the key genetic components responsible for the reduction in cotton yield in saline-alkali soils are still unclear.

Results: Here, we evaluated three main components of lint yield, single boll weight (SBW), lint percentage (LP) and boll number per plant (BNPP), across 316 G. hirsutum accessions under four salt conditions over two years. Phenotypic analysis indicated that LP was unchanged under different salt conditions, however BNPP decreased significantly and SBW increased slightly under high salt conditions. Based on 57,413 high-quality single nucleotide polymorphisms (SNPs) and genome-wide association study (GWAS) analysis, a total of 42, 91 and 25 stable quantitative trait loci (QTLs) were identified for SBW, LP and BNPP, respectively. Phenotypic and QTL analysis suggested that there was little correlation among the three traits. For LP, 8 stable QTLs were detected simultaneously in four different salt conditions, while fewer repeated QTLs for SBW or BNPP were identified. Gene Ontology (GO) analysis indicated that their regulatory mechanisms were also quite different. Via transcriptome profile data, we detected that 10 genes from the 8 stable LP QTLs were predominantly expressed during fiber development. Further, haplotype analyses found that a MYB gene (GhMYB103), with the two SNP variations in cis-regulatory and coding regions, was significantly correlated with lint percentage, implying a crucial role in lint yield. We also identified that 40 candidate genes from BNPP QTLs were salt-inducible. Genes related to carbohydrate metabolism and cell structure maintenance were rich in plants grown in high salt conditions, while genes related to ion transport were active in plants grown in low salt conditions, implying different regulatory mechanisms for BNPP at high and low salt conditions.

Conclusions: This study provides a foundation for elucidating cotton salt tolerance mechanisms and contributes gene resources for developing upland cotton varieties with high yields and salt stress tolerance.
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http://dx.doi.org/10.1186/s12870-019-2187-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6961271PMC
January 2020

Preparation and Characterization of β-glucosidase Films for Stabilization and Handling in Dry Configurations.

Curr Pharm Biotechnol 2020 ;21(8):741-747

State Key Laboratory of Crop Genetics & Germplasm Enhancement, Nanjing Agricultural University, Nanjing, China.

Background: Although the stability of proteins is of significance to maintain protein function for therapeutical applications, this remains a challenge. Herein, a general method of preserving protein stability and function was developed using gelatin films.

Methods: Enzymes immobilized onto films composed of gelatin and Ethylene Glycol (EG) were developed to study their ability to stabilize proteins. As a model functional protein, β-glucosidase was selected. The tensile properties, microstructure, and crystallization behavior of the gelatin films were assessed.

Results: Our results indicated that film configurations can preserve the activity of β-glucosidase under rigorous conditions (75% relative humidity and 37°C for 47 days). In both control films and films containing 1.8 % β-glucosidase, tensile strength increased with increased EG content, whilst the elongation at break increased initially, then decreased over time. The presence of β-glucosidase had a negligible influence on tensile strength and elongation at break. Scanning electron-microscopy (SEM) revealed that with increasing EG content or decreasing enzyme concentrations, a denser microstructure was observed.

Conclusion: In conclusion, the dry film is a promising candidate to maintain protein stabilization and handling. The configuration is convenient and cheap, and thus applicable to protein storage and transportation processes in the future.
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http://dx.doi.org/10.2174/1389201020666191202145351DOI Listing
August 2020

Autophagy inhibits the mesenchymal stem cell aging induced by D-galactose through ROS/JNK/p38 signalling.

Clin Exp Pharmacol Physiol 2020 03 26;47(3):466-477. Epub 2019 Nov 26.

Department of Clinical Medicine, School of Medicine, Zhejiang University City College, Hangzhou, China.

Autophagy and cellular senescence are two critical responses of mammalian cells to stress and may have a direct relationship given that they respond to the same set of stimuli, including oxidative stress, DNA damage, and telomere shortening. Mesenchymal stem cells (MSCs) have emerged as reliable cell sources for stem cell transplantation and are currently being tested in numerous clinical trials. However, the effects of autophagy on MSC senescence and corresponding mechanisms have not been fully evaluated. Several studies demonstrated that autophagy level increases in aging MSCs and the downregulation of autophagy can delay MSC senescence, which is inconsistent with most studies that showed autophagy could play a protective role in stem cell senescence. To further study the relationship between autophagy and MSC senescence and explore the effects and mechanisms of premodulated autophagy on MSC senescence, we induced the up- or down-regulation of autophagy by using rapamycin (Rapa) or 3-methyladenine, respectively, before MSC senescence induced by D-galactose (D-gal). Results showed that pretreatment with Rapa for 24 hours remarkably alleviated MSC aging induced by D-gal and inhibited ROS generation. p-Jun N-terminal kinases (JNK) and p-38 expression were also clearly decreased in the Rapa group. Moreover, the protective effect of Rapa on MSC senescence can be abolished by enhancing the level of ROS, and p38 inhibitor can reverse the promoting effect of H O on MSC senescence. In summary, the present study indicates that autophagy plays a protective role in MSC senescence induced by D-gal, and ROS/JNK/p38 signalling plays an important mediating role in autophagy-delaying MSC senescence.
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http://dx.doi.org/10.1111/1440-1681.13207DOI Listing
March 2020

Rapid, label-free detection of cerebral ischemia in rats using hyperspectral imaging.

J Neurosci Methods 2020 01 16;329:108466. Epub 2019 Oct 16.

Department of Neurosurgery, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China. Electronic address:

Background: Stroke is the third most common cause of disability and the second most common cause of death worldwide. Ischemia, one of the two broad categories of stroke, is characterized by a lack of sufficient amounts of blood in order to supply an adequate amount of oxygen and nutrients. It is important to assess the part of the brain that becomes ischemic and necrotic during neurosurgery or experiments in real time. However, there is currently no effective means to achieve this goal.

New Method: We proposed a method based on hyperspectral imaging (HSI) for the real-time detection of a varied range of ischemic brain tissues in vivo or ex vivo and assessed the practical utility of a model of ischemic stroke in rats.

Results: The results showed that hyperspectral images processed with a ratio of spectral reflectance at 545 and 560 nm (R545/R560) could identify early brain ischemia and accurately show regions of ischemia.

Comparison With Existing Methods: We verified the area imaged by HSI using hematoxylin and eosin (HE) and 2, 3, 5-triphenyltetrazolium chloride (TTC) staining methods. This technique could precisely image the ischemic part of the brain in vivo and ex vivo.

Conclusions: These results demonstrate the practical utility of HSI for the real-time detection of cerebral ischemia in rats. By providing rapid assessment of brain tissue perfusion, HSI may help doctors recognize ischemic regions quickly and precisely during surgery as well as have great utility in the experimental process.
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http://dx.doi.org/10.1016/j.jneumeth.2019.108466DOI Listing
January 2020

Identifying and quantifying potential super-spreaders in social networks.

Sci Rep 2019 10 15;9(1):14811. Epub 2019 Oct 15.

School of Computer Science and Technology, Harbin Institute of Technology, Weihai, 264209, China.

Quantifying the nodal spreading abilities and identifying the potential influential spreaders has been one of the most engaging topics recently, which is essential and beneficial to facilitate information flow and ensure the stabilization operations of social networks. However, most of the existing algorithms just consider a fundamental quantification through combining a certain attribute of the nodes to measure the nodes' importance. Moreover, reaching a balance between the accuracy and the simplicity of these algorithms is difficult. In order to accurately identify the potential super-spreaders, the CumulativeRank algorithm is proposed in the present study. This algorithm combines the local and global performances of nodes for measuring the nodal spreading abilities. In local performances, the proposed algorithm considers both the direct influence from the node's neighbourhoods and the indirect influence from the nearest and the next nearest neighbours. On the other hand, in the global performances, the concept of the tenacity is introduced to assess the node's prominent position in maintaining the network connectivity. Extensive experiments carried out with the Susceptible-Infected-Recovered (SIR) model on real-world social networks demonstrate the accuracy and stability of the proposed algorithm. Furthermore, the comparison of the proposed algorithm with the existing well-known algorithms shows that the proposed algorithm has lower time complexity and can be applicable to large-scale networks.
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http://dx.doi.org/10.1038/s41598-019-51153-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6794301PMC
October 2019

Enhanced electron transportation of PF-NR cathode interface by gold nanoparticles.

Nanoscale Res Lett 2019 Jul 30;14(1):261. Epub 2019 Jul 30.

Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang, 621900, China.

In order to achieve a wider organic light-emitting diode (OLED) commercial popularity, solution processing inverted polymer light-emitting diode (iPLED) is a trend for further development, but there is still a gap for solution processing devices to achieve commercialization. The improvement of the performance iPLEDs is a research topic of intense current interest. The modification of the cathode interface layer of poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PF-NR) can greatly improve the performance of the devices. However, the electron transportation of the cathode interface layer of PF-NR films is currently poor, and there is substantial interest in improving its electron transportation to further enhance the performance of organic optoelectronic devices. In this paper, gold nanoparticles (Au NPs) with a particle size of 20 nm were prepared and doped into the interface layer PF-NR at a specified ratio. The electron transportation of the interface layer of PF-NR was greatly improved, as judged by conductive atomic force microscopy measurements, which is due to the excellent conductivity of Au NPs. Herein, we demonstrate improved electron transportation of the interface layer by doping Au NPs in PF-NR film, which provides important and practical theoretical guidance and technical support for the preparation of high performance organic optoelectronic devices.
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http://dx.doi.org/10.1186/s11671-019-3090-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6667568PMC
July 2019

Combining genome-wide and transcriptome-wide analyses reveal the evolutionary conservation and functional diversity of aquaporins in cotton.

BMC Genomics 2019 Jul 1;20(1):538. Epub 2019 Jul 1.

State Key Laboratory of Crop Genetics & Germplasm Enhancement, Engineering Research Center of Hybrid Cotton Development Ministry of Education, Nanjing Agricultural University, Nanjing, 210095, Jiangsu Province, People's Republic of China.

Background: Aquaporins (AQPs) are integral membrane proteins from a larger family of major intrinsic proteins (MIPs) and function in a huge variety of processes such as water transport, plant growth and stress response. The availability of the whole-genome data of different cotton species allows us to study systematic evolution and function of cotton AQPs on a genome-wide level.

Results: Here, a total of 53, 58, 113 and 111 AQP genes were identified in G. arboreum, G. raimondii, G. hirsutum and G. barbadense, respectively. A comprehensive analysis of cotton AQPs, involved in exon/intron structure, functional domains, phylogenetic relationships and gene duplications, divided these AQPs into five subfamilies (PIP, NIP, SIP, TIP and XIP). Comparative genome analysis among 30 species from algae to angiosperm as well as common tandem duplication events in 24 well-studied plants further revealed the evolutionary conservation of AQP family in the organism kingdom. Combining transcriptome analysis and Quantitative Real-time PCR (qRT-PCR) verification, most AQPs exhibited tissue-specific expression patterns both in G. raimondii and G. hirsutum. Meanwhile, a bias of time to peak expression of several AQPs was also detected after treating G. davidsonii and G. hirsutum with 200 mM NaCl. It is interesting that both PIP1;4 h/i/j and PIP2;2a/e showed the highly conserved tandem structure, but differentially contributed to tissue development and stress response in different cotton species.

Conclusions: These results demonstrated that cotton AQPs were structural conservation while experienced the functional differentiation during the process of evolution and domestication. This study will further broaden our insights into the evolution and functional elucidation of AQP gene family in cotton.
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http://dx.doi.org/10.1186/s12864-019-5928-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6604486PMC
July 2019

Full-field burn depth detection based on near-infrared hyperspectral imaging and ensemble regression.

Rev Sci Instrum 2019 Jun;90(6):064103

Department of Burns, The First Affiliated Hospital Sun Yat-Sen University, Guangzhou 510080, China.

The accurate and instant diagnosis of burn severity is always the key point of optimal wound management and clinical treatment. However, the accuracy of burn depth assessment is low via visual inspection and lacks a quantitative measurement. In this work, a full-field burn depth detection system is proposed using the near-infrared hyperspectral imaging with the ensemble regression. The rotational feature subspace ensemble regression is introduced to establish a complex regression model between the hyperspectral imaging data and the burn depth. By the in vivo measurement of a porcine model, the method can get the average relative error about 7% for the burn depth measurement, which demonstrates that the proposed method can perform an accurate full-field assessment of burn depth and provide more practical references for clinicians.
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http://dx.doi.org/10.1063/1.5034503DOI Listing
June 2019

Appropriate Donor-Acceptor Phase Separation Structure for the Enhancement of Charge Generation and Transport in Polymer Solar Cells.

Polymers (Basel) 2018 Mar 18;10(3). Epub 2018 Mar 18.

Department of Chemistry, Renmin University of China, Beijing 100872, China.

The morphology of active layer for polymer solar cells is critical to enhance the performance especially for fill factor of the devices. To investigate the relationship between active layer morphology and performance of polymer solar cells (PSCs), 1,8-diiodooctane (DIO) additive, and [6,6]-phenyl-C-butyric acid methyl ester (PCBM) electron acceptor were used to regulate the aggregation morphology of copolymer poly(thieno[3,4-b]-thiophene/benzodithiophene) (PTB7) electron donor from solution state to solid state. Atom force microscopy (AFM), steady-state absorption (UV-Vis), time-resolved absorption (TA), spectroelectrochemistry (SEC) and current-voltage (J-V) measurements were employed to characterize the morphology, optical and electrical characteristics of active layers and to reveal the relationship among the morphology, photophysical property, and performance of PTB7-based devices. The results show that DIO can refine the aggregation scale of PTB7 during the dissolution process, whereas both the aggregation scale and aggregation behaviors of PTB7 donor are affected by PCBM acceptor molecules. Furthermore, the bulk heterojunction structure (BHJ) morphology of active layer can be optimized during the DIO evaporation process. TA kinetic data indicate that the population and lifetime of charged species are improved in the DIO-treated BHJ active layer. Moreover, the active layers with DIO treatment have a relative low highest occupied molecular orbital (HOMO) energy level, which makes hole transport more easily in PTB7 donor phase. As a result, the performance of PTB7-based PSCs is enhanced.
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http://dx.doi.org/10.3390/polym10030332DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6414981PMC
March 2018

Multiple parapatric pollinators have radiated across a continental fig tree displaying clinal genetic variation.

Mol Ecol 2019 05 31;28(9):2391-2405. Epub 2019 May 31.

CEFE, CNR, EPHE, IRD, Université de Montpellier, Université Paul-Valéry Montpellier, Montpellier, France.

The ways that plant-feeding insects have diversified are central to our understanding of terrestrial ecosystems. Obligate nursery pollination mutualisms provide highly relevant model systems of how plants and their insect associates have diversified and the over 800 species of fig trees (Ficus) allow comparative studies. Fig trees can have one or more pollinating fig wasp species (Agaonidae) that breed within their figs, but factors influencing their number remain to be established. In some widely distributed fig trees, the plants form populations isolated by large swathes of sea, and the different populations are pollinated by different wasp species. Other Ficus species with continuous distributions may present genetic signatures of isolation by distance, suggesting more limited pollinator dispersal, which may also facilitate pollinator speciation. We tested the hypothesis that Ficus hirta, a species for which preliminary data showed genetic isolation by distance, would support numerous pollinator species across its range. Our results show that across its range F. hirta displays clinal genetic variation and is pollinated by nine parapatric species of Valisia. This is the highest number of pollinators reported to date for any Ficus species, and it is the first demonstration of the occurrence of parapatric pollinator species on a fig host displaying continuous genetic structure. Future comparative studies across Ficus species should be able to establish the plant traits that have driven the evolution of pollinator dispersal behaviour, pollinator speciation and host plant spatial genetic structure.
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http://dx.doi.org/10.1111/mec.15046DOI Listing
May 2019

Traditional Uses, Botany, Phytochemistry, Pharmacology, Pharmacokinetics and Toxicology of L.: A Review.

Molecules 2019 Jan 19;24(2). Epub 2019 Jan 19.

School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, China.

L. (Asteraceae) is a common and well-known traditional Chinese herbal medicine usually named Cang-Er-Zi, and has been used for thousands of years in China. The purpose of this paper is to summarize the progress of modern research, and provide a systematic review on the traditional usages, botany, phytochemistry, pharmacology, pharmacokinetics, and toxicology of the . Moreover, an in-depth discussion of some valuable issues and possible development for future research on this plant is also given. , as a traditional herbal medicine, has been extensively applied to treat many diseases, such as rhinitis, nasal sinusitis, headache, gastric ulcer, urticaria, rheumatism bacterial, fungal infections and arthritis. Up to now, more than 170 chemical constituents have been isolated and identified from , including sesquiterpenoids, phenylpropenoids, lignanoids, coumarins, steroids, glycosides, flavonoids, thiazides, anthraquinones, naphthoquinones and other compounds. Modern research shows that the extracts and compounds from possess wide-ranging pharmacological effects, including anti- allergic rhinitis (AR) effects, anti-tumor effects, anti-inflammatory and analgesic effects, insecticide and antiparasitic effects, antioxidant effects, antibacterial and antifungal effects, antidiabetic effects, antilipidemic effects and antiviral effects. However, further research should focus on investigating bioactive compounds and demonstrate the mechanism of its detoxification, and more reasonable quality control standards for should also be established.
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http://dx.doi.org/10.3390/molecules24020359DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6359306PMC
January 2019