ANALYTICAL CHEMISTRY
·
2021
·
IF 6.986
Liu Shi,Lin Wang,Xuemei Ma,Xiaona Fang,Liangliang Xiang,Yongxiang Yi,Jinlong Li,Zhaofeng Luo,Genxi Li
With the outbreak of COVID-19, which is fast transmitting and highly contagious, the development of rapid, highly specific, and sensitive detection kits has become a research hotspot. The existing assay methods for SARS-CoV-2 are mainly based on enzymatic reactions, which require expensive reagents, hindering popular use, especially in resource-constrained areas. Herein, we propose an aptamer-based method for the assay of SARS-CoV-2 via binding of the spike protein using functionalized biomimetic nanochannels. To get the analogous effect of human ACE2, a receptor for the spike protein, the aptamer to bind to the spike S1 protein has been first screened by a SELEX technique and then immobilized on the previously prepared nanochannels. In the presence of SARS-CoV-2, the changes in steric hindrance and charge density on the surface of the nanochannels will affect the ion transport, along with a rapid electrochemical response. Our method has been successfully applied to detect the viral particles in clinical pharyngeal swab specimens in one step without sample treatment. We expect this rapid, reagent-free, and sensitive assay method to be developed as a useful tool for diagnosing COVID-19.
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高影响因子
CELLULOSE
·
2018
·Vol. 25
·期 7
·3843-3851
·
IF 3.809
Hu Hui-Chao,Zhang Yu,Zeng Tong,Zhou Weining,Chen Lihui,Huang Liulian,Ni Yonghao
This paper reports a robust method for rapid determination of cellulose derived 5-hydroxymethyl-2-furfural (5-HMF) in biomass hydrolysate suspension based on headspace gas chromatography (HS-GC). The headspace equilibration at 150 °C for longer than 4 min with a pH range of 2.0–3.5 and a 50% (v/v) of ethanol content can obtain the full evaporation of 5-HMF, and eliminate the formation of additional 5-HMF generation from hexose. The linear GC response of 5-HMF was achieved by controlling the sample size within 20 μL. The results showed that this method has a good precision (relative standard deviation < 6.97%) and accuracy (recoveries ranged from 94.0 to 104.8%). The limit of quantification of the method was 51 mg/L. It was also found that a considerable amount of furfural (13.8%) and 5-HMF (18.7%) was adsorbed on condensed lignin and humins in residual biomass, and the washing procedure with ethanol can completely extract the adsorbed furfural and 5-HMF. The present method is accurate, simple, and robust, it will be a powerful tool for determining the content of 5-HMF in the liquid samples from biorefinery related processes.
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INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2022
·Vol. 23
·期 10
·5715
·
IF 6.208
He Wang,Jingjing Li,Qian Yang,Lan Wang,Jing Wang,Yaxin Zhang,Yanjing Guo,Rui Li,Ruiqi Zhang,Xiaorong Tao,Bernal E. Valverde,Sheng Qiang,Hazem M. Kalaji,Shiguo Chen
2-Amino-3-methylhexanoic acid (AMHA) was synthetized as a non-natural amino acid more than 70 years ago; however, its possible function as an inducer of plant resistance has not been reported. Plant resistance inducers, also known as plant elicitors, are becoming a novel and important development direction in crop protection and pest management. We found that free AMHA accumulated in the mycelia but not in fermentation broths of four fungal species,Magnaporthe oryzaeand threeAlternariaspp. We unequivocally confirmed that AMHA is a naturally occurring endogenous (2S, 3S)-α-amino acid, based on isolation, purification and structural analyses. Further experiments demonstrated that AMHA has potent activity-enhancing resistance against extreme temperature stresses in several plant species. It is also highly active against fungal, bacterial and viral diseases by inducing plant resistance. AMHA pretreatment strongly protected wheat against powdery mildew,ArabidopsisagainstPseudomonas syringaeDC3000 and tobacco againstTomato spotted wilt virus. AMHA exhibits a great potential to become a unique natural elicitor protecting plants against biotic and abiotic stresses.Keywords:agricultural production;natural product;plant resistance inducer;biopesticide;biotic and abiotic stress
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Journal of the American Chemical Society
·
2017
·
IF 13.858
Yuyang Zhang,Yi Zou,Nelson L. Brock,Tingting Huang,Yingxia Lan,Xiaozheng Wang,Zixin Deng,Yi Tang,Shuangjun Lin
3-Substituted 2-oxindoles are important structural motifs found in many biologically active natural products and pharmaceutical lead compounds. Here, we report an enzymatic formation of the 3-substituted 2-oxindoles catalyzed by MarE in the maremycin biosynthetic pathway in Streptomyces sp. B9173. MarE is a homologue of FeII/heme-dependent tryptophan 2,3-dioxygenases (TDOs). Typical TDOs usually catalyze the insertion of two oxygen atoms from O2 into an indole ring to generate N-formylkynurenine (NFK)-like products. In contrast, MarE catalyzes the insertion of a single oxygen atom from O2 into an indole ring, to probably generate an epoxyindole intermediate that undergoes an unprecedented 2,3-hydride migration to form 2-oxindole structure. MarE shows substrate robustness to catalyze the conversion of a series of 3-substituted indoles into their corresponding 3-substituted 2-oxindoles. Although containing most key amino acid residues conserved in well-known TDO homologues, MarE falls into a separate new subgroup in the phylogenetic tree. The characterization of MarE and its homologue enriches the functional diversities of TDO superfamily and provides a new strategy for discovering novel natural products containing 3-substituted 2-oxindole pharmacophores by genome mining.
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高影响因子
Desalination and Water Treatment
·
2014
·
IF 0.987
Ling Li,Jun Cheng Li,Zhuang Rao,Gong Wu Song,Bin Hu
The adsorpion of methylene blue from aqueous solution on a highly porous metal-organic framework material [Cu3(BTC)2(H2O)3] was studied in conjunction with the adsorption isotherm, kinetics and regenerate of the sorbent. The adsorption isotherms of methylene blue on [Cu3(BTC)2(H2O)3] followed both the Freundlich isotherm and the Langmuir adsorption isotherm. Adsorption kinetics was determined from the experimental data, and the results showed that the adsorption obeyed a pseudo-second-order kinetics. The best oscillate time and the best [Cu3(BTC)2(H2O)3] amount were discussed, and [Cu3(BTC)2(H2O)3] gave high adsorption in only 5 minutes. The used [Cu3(BTC)2(H2O)3] could be regenerated by glycol solution, thus recycled. SEM image and FT-TR spectra of recycled [Cu3(BTC)2(H2O)3] after different adsorption times were compared. The high adsorption capacity and excellent reusability make [Cu3(BTC)2(H2O)3] attractive for the removal of methylene blue from aqueous solution.
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Journal of Biomedical Nanotechnology
·
2022
·Vol. 18
·期 11
·2470-2478
·
IF 3.641
Tu Rong,You Xiaoguang,Ding Zhichao,Wu Huanyu,Zhao Linlu,Qiu Zhi,Wei Junjie,Yang Xiaofeng
Development of imaging methods that can detect target molecules will be of great significance for non-invasive molecular diagnosis. Vascular endothelial growth factor receptor-2 (VEGFR-2) is a broadly expressed target, and VEGFR-2-specific agents have been used in biological therapy.
In this study, amine-reactive coupling was used to label the polypeptide VEGF125–136 with a Gd(DOTA) complex to create a magnetic resonance contrast agent, VEGF125–136-Gd, which binds to VEGFR-2. Using T1-weighted magnetic resonance imaging, we explored the tumor cell-targeting
ability of VEGF125–136-Gd and its enhancement of T1-weighted image intensity using human hepatoma (HepG2) cells and found that the signal-to-noise ratio (SNR) increased commensurately with the concentration of VEGF125–136-Gd. At a concentration of 2 mM, the SNR produced by VEGF125–136-Gd
was 5.4-fold higher than that produced by a Gd-labelled non-targeting polypeptide (NTPP-Gd) control. We also evaluated the tumor-targeting efficiency of VEGF125–136-Gd in nude mice injected with human hepatoma (HepG2) cells. Preliminary in vivo imaging of VEGFR-2 in tumor tissue
revealed a targeting peak 60 min post administration of VEGF125–136-Gd, the intensity of which was 23% higher than the SNR of NTPP-Gd at the same time point. Our findings may help lay the foundation for clinical applications of VEGF125–136-Gd in targeted imaging.
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高影响因子
POWDER TECHNOLOGY
·
2021
·
IF 5.134
Mingyu Zheng,Tiefeng Peng,Yanhong Wang,Liqun Luo,Wei Shao,Jiaqi Gao,Qi Lu
Selective separation of pyrite and galena using 2-mercaptobenzimidazole (MBI) as a chelating collector, was investigated by flotation , scanning electron microscope (SEM), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations. Single-mineral flotation showed a significant flotability of pyrite at pH = 2–4 and galena at pH = 8–10 in the presence of MBI. The depressant effect of pyrite was observed to be more pronounced under alkaline conditions. Artificially mixed minerals flotation suggested the galena-pyrite could be separated under alkaline conditions, especially at pH = 10. SEM analysis indicates that the adsorption of MBI on galena surface is more intense than pyrite. However, the interaction between MBI and pyrite is stronger than that of MBI-galena. FT-IR analysis shows the iron and lead ions may chelate with -N = and -SH groups of MBI. Pyrite contains more iron hydroxide (or sulfate forms) in solution from XPS analysis, only half of the metallic ions on the surface function as active sites, thus reducing the amount of metal that can be chelated with MBI. DFT calculations revealed that MBI was often in the molecular form under acidic mediums and the ionic form under alkaline condition, while the ionic form of MBI was more active.
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高影响因子
OncoTargets and Therapy
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2019
·
IF 3.046
Xiaolin Pu,Changqing Dong,Wenyu Zhu,Wei Li,Hua Jiang
Purpose Toll-like receptor 4 (TLR4) is involved in the inflammation in liver cancer. High-expressed stomatin-like protein 2 (SLP-2) is commonly reported in many cancer types. This study aims to investigate the functions of SLP-2 in TLR4-mediated inflammatory responses and tumor progression of liver cancer. Patients and methods Plasmid transfection technique was applied to silence and overexpress genes. Changes in cell viability and apoptosis were determined by performing cell counting kit-8 assay and flow cytometry. The levels of pro-inflammatory cytokines were determined by ELISA. We further measured the several types of the malignant transformation of SK-Hep1 cells to assess the effects of SLP-2 silencing on the cell migration and invasion, proliferation and angiogenesis of liver cancer in vitro. Western blot and RT-qPCR were performed for expression analysis. Results Lipopolysaccharide (LPS) promoted the cell proliferation of SK-Hep1 and production of tumor necrosis factor-α (TNF-α) and IL-6. SLP-2 silencing could inhibit the protein and mRNA levels of CD14 and Cdc42 and subsequently inhibited the levels of TNF-α and IL-6. Overexpressed CD14 not only remarkably reversed the proapoptotic ability of SLP-2 silencing and promoted the expression of Cdc42 and production of TNF-α and IL-6, but also notably reversed the inhibitory effects on the malignant abilities of SK-Hep1 cells by SLP-2 silencing. Conclusion SLP-2 silencing could significantly attenuate the inflammatory responses and tumor progression of liver cancer via inhibiting LPS/TLR4 signal transduction through the repression of CD14.
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高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2016
·
IF 3.902
Lu Chen,Jun Lin,Juan Li,Xiaozhao Wang,Junjun Zhuang,Huiming Wang,Kui Cheng,Wenjian Weng
In this study, mineralized collagen (COL) coatings with controlled loading and release of bone morphogenetic protein (rhBMP-2) as well as enhanced osteogenic differentiation were successfully achieved via the spatially-control of hydroxypropyltrimethyl ammonium chloride chitosan (HACC) within the coatings. The distribution of HACC in the inner part (HACC-IN) or the outer part (HACC-OUT) of the coatings were adjusted by different potential values and negative/positive alternations during alternating potentials assisted electrochemical deposition (AP-ECD). It was found that rhBMP-2 loading capacity was remarkably enhanced with the increased incorporation of HACC due to their strong interaction, and the release behavior was also tuned by HACC location. In general, HACC-IN coatings showed a prominent improvement in cytocompatibility and osteogenic differentiation. The main reason is considered that the inner location of HACC can eliminate the negative effect of HACC to initial cellular adhesion and bring to a sustained rhBMP-2 release behavior due to kinetic modification. An optimized coating in this work could load as high as 4644 ng/cm 2 rhBMP-2 and release only 25% for 14 days, which consequently leads to a better osteogenic differentiation. This study has thus inspired another promising protocol for designing growth factor incorporated bioactive coatings for bone implants with improved osteointegration.
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高影响因子
JOURNAL OF NEUROSCIENCE
·
2021
·Vol. 41
·期 23
·4976-4990
·
IF 6.167
Jinxing Hou,Huiru Bi,Zhuoyang Ye,Wenhui Huang,Gang Zou,Xiaochuan Zou,Yun Stone Shi,Ying Shen,Quanhong Ma,Frank Kirchhoff,Yimin Hu,Guiquan Chen
Mutations on γ-secretase subunits are associated with neurologic diseases. Whereas the role of γ-secretase in neurogenesis has been intensively studied, little is known about its role in astrogliogenesis. Recent evidence has demonstrated that astrocytes can be generated from oligodendrocyte precursor cells (OPCs). However, it is not well understood what mechanism may control OPCs to differentiate into astrocytes. To address the above questions, we generated two independent lines of oligodendrocyte lineage-specific presenilin enhancer 2 (Pen-2) conditional KO mice. Both male and female mice were used. Here we demonstrate that conditional inactivation of Pen-2 mediated by Olig1-Cre or NG2-CreERT2 causes enhanced generation of astrocytes. Lineage-tracing experiments indicate that abnormally generated astrocytes are derived from Cre-expressing OPCs in the CNS in Pen-2 conditional KO mice. Mechanistic analysis reveals that deletion of Pen-2 inhibits the Notch signaling to upregulate signal transducer and activator of transcription 3, which triggers activation of GFAP to promote astrocyte differentiation. Together, these novel findings indicate that Pen-2 regulates the specification of astrocytes from OPCs through the signal transducer and activator of transcription 3 signaling.SIGNIFICANCE STATEMENT Astrocytes and oligodendrocyte (OLs) play critical roles in the brain. Recent evidence has demonstrated that astrocytes can be generated from OL precursor cells (OPCs). However, it remains poorly understood what mechanism governs the differentiation of OPCs into astrocytes. In this study, we took advantage of OL lineage cells specific presenilin enhancer 2 (Pen-2) conditional KO mice. We show that deletion of Pen-2 leads to dramatically enhanced astrocyte differentiation from OPCs in the CNS. Mechanistic analysis reveals that deletion of Pen-2 inhibits Hes1 and activates signal transducer and activator of transcription 3 to trigger GFAP activation which promotes astrocyte differentiation. Overall, this study identifies a novel function of Pen-2 in astrogliogenesis from OPCs.
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高影响因子
Journal of Materials Chemistry B
·
2023
·
IF 7
Yanhao Zhang,Ji Wang,Hanlei Xing,Chao Liu,Wenhui Zha,Shuo Dong,Yuhao Jiang,Xinsong Li
mRNA vaccines have emerged as a highly promising approach for preventing cancer and infectious diseases, attributed to their superior immunogenicity, rapid development speed, and quality-controlled scale production. While homologous mRNA vaccine administration is currently the most prevalent method employed in clinical settings, heterologous administration is a promising avenue worth exploring. In this report, two types of mRNA vaccine formulations for SARS-CoV-2 infection were developed based on different lipid nanoparticle (LNP) delivery systems, and heterologous and homologous mRNA vaccinations were administered to explore the levels of immune responses comparatively. First, five novel H-series ionizable lipids were synthesized and confirmed by NMR and MS. Subsequently, six SARS-CoV-2 receptor-binding domain (RBD) mRNA-encapsulated LNP formulations were prepared using a microfluidic mixer based on H-series and MC3 lipids. These formulations exhibited spherical structures with an average diameter ranging from 90–140 nm, as characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The safety of these formulations was confirmed in vitro by the cytotoxicity assay. Moreover, transfection assay, lysosomal escape test, and western blot, and in vivo biodistribution analyses collectively demonstrated that lipids H03 and MC3 exhibited superior in vitro and in vivo delivery efficacy in comparison to other H-series lipids. Notably, H03-Fluc mRNA exhibited an approximately 2.2-fold higher in vivo bioluminescence signal intensity than MC3-Fluc mRNA. Additionally, evaluation of humoral immunity demonstrated that homologous H03-mRNA vaccination elicited an immune response that was approximately 3-fold higher than that of homologous MC3-mRNA vaccination. More significantly, the heterologous H03-mRNA/MC3-mRNA vaccination elicited an immune response that was approximately 2-3-fold higher than that of homologous H03-mRNA vaccination and 6–9-fold higher than that of homologous MC3-mRNA vaccination, without any observable adverse effects. These results suggest that heterologous mRNA vaccination is superior to homologous mRNA vaccination and may be attributed to differences in LNP carriers. Therefore, our research may inspire further exploration of different delivery systems to enhance mRNA-based therapeutics.
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高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2015
·
IF 4.152
Zhenzhen Liu,Yong Tang,Ting Kang,Minyu Rao,Kejia Li,Qin Wang,Changyun Quan,Chao Zhang,Qing Jiang,Huiyong Shen
HA and bone morphogenetic protein-2 (BMP-2) possess superior osteoinductive and osteoconductive activities in the repair of bone defects. In this study, a BMP-2 mimicking oligopeptide (serine–serine–valine–proline–threonine, SSVPT) was introduced to the surface of nano-sized HA as the reinforcement phase of a poly(methyl methacrylate) (PMMA) cement, and the synergistic action of HA and oligopeptide on the bioactivity of HA/PMMA bone cement was investigated. Incorporated with 3-trimethoxysilyl propyl methacrylate (MPS)-modified HA, the compressive strength, flexural strength, and flexural modulus of HA/PMMA complied with the international standardization organization 5833 standard. Adherence measurement demonstrated that the introduction of HA and SSVPT could promote the adhesion and proliferation of human fetal osteoblast (hFOB) on the surface of HA/PMMA cement. The increased alkaline phosphatase (ALP) activity indicated that HA/PMMA could promote osteogenic differentiation of hFOB. All of the results illuminated that the HA/PMMA cement could be used as a bioactive material for regeneration and reconstruction of load-bearing bone.
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