303 results on '"Jianzhao Liu"'
Search Results
52. Mapping messenger RNA methylations at single base resolution
- Author
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Xinhua Feng, Jianzhao Liu, Jie Cao, and Xiao Shu
- Subjects
0301 basic medicine ,Adenosine ,Resolution (mass spectrometry) ,Computational biology ,Biology ,010402 general chemistry ,Methylation ,01 natural sciences ,Biochemistry ,Cell Line ,Epigenesis, Genetic ,Analytical Chemistry ,03 medical and health sciences ,Gene expression ,Humans ,RNA, Messenger ,Amines ,RNA Processing, Post-Transcriptional ,Aldehydes ,Messenger RNA ,Base Sequence ,Guanosine ,Staining and Labeling ,Single Molecule Imaging ,0104 chemical sciences ,030104 developmental biology ,Gene Expression Regulation ,MRNA methylation - Abstract
The messenger RNA (mRNA) methylations in mammalian cells have been found to contain N6-methyladenosine (m6A), N6-2'-O-dimethyladenosine (m6Am), 7-methylguanosine (m7G), 1-methyladenosine (m1A), 5-methylcytosine (m5C), and 2'-O-methylation (2'-OMe). Their regulatory functions in control of mRNA fate and gene expression are being increasingly uncovered. To unambiguously understand the critical roles of mRNA methylations in physiological and pathological processes, mapping these methylations at single base resolution is highly required. Here, we will review the progresses made in methylation sequencing methodologies developed mainly in recent two years, with an emphasis on chemical labeling-assisted single base resolution methods, and discuss the problems and prospects as well.
- Published
- 2021
53. Socially-interactive dressing room: an iterative evaluation on interface design.
- Author
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Jasy Suet Yan Liew, Elizabeth Kaziunas, JianZhao Liu, and Shen Zhuo
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- 2011
- Full Text
- View/download PDF
54. SUMOylation regulates pre-mRNA splicing to overcome DNA damage in fungi
- Author
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Yunqing Jian, Xia Chen, Kewei Sun, Zunyong Liu, Danni Cheng, Jie Cao, Jianzhao Liu, Xiaofei Cheng, Liang Wu, Feng Zhang, Yuming Luo, Matthias Hahn, Zhonghua Ma, and Yanni Yin
- Subjects
Physiology ,Plant Science - Abstract
● Pathogenic fungi are subject to DNA damage stress derived from host immune responses during infection. SUMO modification and precursor (pre)-mRNA splicing are both involved in DNA damage response (DDR). However the mechanisms of how SUMOylation and splicing coordinated in DDR remain largely unknown. ● Combining with biochemical analysis, RNA-seq method, and biological analysis, we report that SUMO pathway participates in DDR and virulence in Fusarium graminearum, a causal agent of Fusarium head blight of cereal crops worldwide. Interestingly, a key transcription factor FgSR is SUMOylated upon DNA damage stress. ● SUMOylation regulates FgSR nuclear-cytoplasmic partitioning and its phosphorylation by FgMec1, and promotes its interaction with chromatin remodeling complex SWI/SNF for activating the expression of DDR-related genes. Moreover, the SWI/SNF complex was found to further recruit splicing-related NineTeen Complex, subsequently modulates pre-mRNAs splicing during DDR. ● Our findings reveal a novel function of SUMOylation in DDR by regulating a transcription factor to orchestrate gene expression and pre-mRNA splicing to overcome DNA damage during the infection of F. graminearum, which advances the understanding of the delicate regulation of DDR by SUMOylation in pathogenic fungi, and extends the knowledge of cooperation of SUMOylation and pre-mRNA splicing in DDR in eukaryotes.
- Published
- 2022
55. Resonant energy transfer between rare earth atomic layers in nanolaminate films
- Author
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Kang Yuan, Yao Liu, Z. T. Ou-Yang, Jianzhao Liu, Yang Yang, and Jiaming Sun
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Atomic and Molecular Physics, and Optics - Abstract
Förster resonant energy transfer between atoms separated at a distance of a few nanometers has strong relevance to different properties of matter. In this work, the resonant energy transfer rate is derived from the electric potential in a system with one dipole interacting with a separated 2D plane of dipoles. It shows an R−2 (R: distance between dipole and 2D plane of dipoles) dependency on the distance of dipole layers, which is different from previous theoretical evaluations with an R−4 dependency. The electroluminescence (EL) properties are studied in different rare earth (Re: Tm, Tb, Ho, Yb, Er) distributed single atomic layer doped Al2O3 nanolaminates prepared by atomic layer deposition, in which the distance between single atomic layers of Re3+ is modulated at the atomic scale. Our theoretical results are consistent with the changes of EL intensity and decay time with the distance between the single atomic rare earth doping layers. This result is crucial for increasing the accuracy in biosensing and design of photonic materials.
- Published
- 2022
56. Environmental stress stimulates microbial activities as indicated by cyclopropane fatty acid enhancement
- Author
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Xinhao Zhu, Ziyu Guo, Nannan Wang, Jianzhao Liu, Yunjiang Zuo, Kexin Li, Changchun Song, Yanyu Song, Chao Gong, Xiaofeng Xu, Fenghui Yuan, and Lihua Zhang
- Subjects
Environmental Engineering ,Environmental Chemistry ,Pollution ,Waste Management and Disposal - Published
- 2023
57. N6-methyladenosine modification-mediated mRNA metabolism is essential for human pancreatic lineage specification and islet organogenesis
- Author
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Xiaojie Ma, Jie Cao, Ziyu Zhou, Yunkun Lu, Qin Li, Yan Jin, Guo Chen, Weiyun Wang, Wenyan Ge, Xi Chen, Zhensheng Hu, Xiao Shu, Qian Deng, Jiaqi Pu, Chengzhen Liang, Junfen Fu, Jianzhao Liu, and Saiyong Zhu
- Subjects
Multidisciplinary ,General Physics and Astronomy ,General Chemistry ,General Biochemistry, Genetics and Molecular Biology - Abstract
Pancreatic differentiation from human pluripotent stem cells (hPSCs) provides promising avenues for investigating development and treating diseases. N6-methyladenosine (m6A) is the most prevalent internal messenger RNA (mRNA) modification and plays pivotal roles in regulation of mRNA metabolism, while its functions remain elusive. Here, we profile the dynamic landscapes of m6A transcriptome-wide during pancreatic differentiation. Next, we generate knockout hPSC lines of the major m6A demethylase ALKBH5, and find that ALKBH5 plays significant regulatory roles in pancreatic organogenesis. Mechanistic studies reveal that ALKBH5 deficiency reduces the mRNA stability of key pancreatic transcription factors in an m6A and YTHDF2-dependent manner. We further identify that ALKBH5 cofactor α-ketoglutarate can be applied to enhance differentiation. Collectively, our findings identify ALKBH5 as an essential regulator of pancreatic differentiation and highlight that m6A modification-mediated mRNA metabolism presents an important layer of regulation during cell-fate specification and holds great potentials for translational applications.
- Published
- 2022
58. N 4 ‐Allyldeoxycytidine: A New DNA Tag with Chemical Sequencing Power for Pinpointing Labelling Sites, Mapping Epigenetic Markers, and In Situ Imaging
- Author
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Donghong Liu, Xiao Shu, Siying Xiang, Tengwei Li, Chenyang Huang, Mohan Cheng, Jie Cao, Yuejin Hua, and Jianzhao Liu
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Organic Chemistry ,Molecular Medicine ,Molecular Biology ,Biochemistry - Published
- 2022
59. A Mutation‐Based Method for Pinpointing a DNA N 6 ‐Methyladenine Methyltransferase Modification Site at Single Base Resolution
- Author
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Yizhen Wang, Jianzhao Liu, Fengqin Wang, Mohan Cheng, Siying Xiang, Minsong Gao, Jie Cao, and Xiao Shu
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Mutation ,biology ,010405 organic chemistry ,Stereochemistry ,DNA polymerase ,Hybridization probe ,Organic Chemistry ,DNA replication ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,DNA methylation ,medicine ,biology.protein ,Molecular Medicine ,A-DNA ,Molecular Biology ,DNA ,Polymerase - Abstract
DNA N6 -methyladenine (6mA) has recently received notable attention due to an increased finding of its functional roles in higher eukaryotes. Here we report an enzyme-assisted chemical labeling method to pinpoint the DNA 6mA methyltransferase (MTase) substrate modification site at single base resolution. A designed allyl-substituted MTase cofactor was applied in the catalytic transfer reaction, and the allyl group was installed to the N6 -position of adenine within a specific DNA sequence to form N6 -allyladenine (6aA). The iodination of 6aA allyl group induced the formation of 1, N6 -cyclized adenine which caused mutations during DNA replication by a polymerase. Thus the modification site could be precisely detected by a mutation signal. We synthesized 6aA deoxynucleoside and deoxynucleotide model compounds and a 6aA-containing DNA probe, and screened nine DNA polymerases to define an optimal system capable of detecting the substrate modification site of a DNA 6mA MTase at single-base resolution.
- Published
- 2021
60. Precise identification of an RNA methyltransferase's substrate modification site
- Author
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Siying Xiang, Jianzhao Liu, Mohan Cheng, Minsong Gao, Jie Cao, Fengqin Wang, Xiao Shu, and Ting Deng
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Adenosine ,Methyltransferase ,Biosensing Techniques ,010402 general chemistry ,medicine.disease_cause ,Methylation ,01 natural sciences ,Catalysis ,Cofactor ,03 medical and health sciences ,Labelling ,Materials Chemistry ,medicine ,Humans ,RNA Processing, Post-Transcriptional ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,Mutation ,Binding Sites ,Base Sequence ,biology ,Metals and Alloys ,RNA ,Substrate (chemistry) ,Methyltransferases ,General Chemistry ,Single Molecule Imaging ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Enzyme ,chemistry ,Biochemistry ,Ceramics and Composites ,biology.protein ,Protein Binding - Abstract
Here we report a simple and nonradioactive biochemical assay which is capable of accurately determining the substrate methylation sites of human RNA N6-methyladenosine methyltransferases METTL3/METTL14 and METTL16. This method employs enzyme-assisted chemical labelling of a specific base in an RNA substrate with the assistance of an allyl-substituted methyltransferase cofactor, and enables precise identification of the labelling site by a mutation signal from standard nucleic acid sequencing. Our method provides a platform to investigate the enzymatic methylations of long and structurally complex RNA substrates, and facilitates the discovery of new methyltransferases.
- Published
- 2021
61. Quantifying the Cloud Water Resource: Methods Based on Observational Diagnosis and Cloud Model Simulation
- Author
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Jietai Mao, Hu Zhijin, Jianzhao Liu, Qianrong Ma, Qi Li, Yuquan Zhou, Tang Yahui, Chao Tan, and Miao Cai
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Atmospheric water ,010504 meteorology & atmospheric sciences ,Meteorology ,business.industry ,Evaporation ,Cloud computing ,010502 geochemistry & geophysics ,01 natural sciences ,Resource (project management) ,Model simulation ,Environmental science ,Satellite ,Precipitation ,business ,Water vapor ,0105 earth and related environmental sciences - Abstract
Based on the concepts of cloud water resource (CWR) and related variables proposed in the first part of this study, this paper provides details of two methods to quantify the CWR. One is diagnostic quantification (CWR-DQ) based on satellite observations, precipitation products, and atmospheric reanalysis data; and the other is numerical quantification (CWR-NQ) based on a cloud resolving model developed at the Chinese Academy of Meteorological Sciences (CAMS). The two methods are applied to quantify the CWR in April and August 2017 over North China, and the results are evaluated against all available observations. Main results are as follows. (1) For the CWR-DQ approach, reference cloud profiles are firstly derived based on the CloudSat/CALIPSO joint satellite observations for 2007–2010. The NCEP/NCAR reanalysis data in 2000–2017 are then employed to produce three-dimensional cloud fields. The budget/balance equations of atmospheric water substance are lastly used, together with precipitation observations, to retrieve CWR and related variables. It is found that the distribution and vertical structure of clouds obtained by the diagnostic method are consistent with observations. (2) For the CWR-NQ approach, it assumes that the cloud resolving model is able to describe the cloud microphysical processes completely and precisely, from which four-dimensional distributions of atmospheric water vapor, hydrometeors, and wind fields can be obtained. The data are then employed to quantify the CWR and related terms/quantities. After one-month continuous integration, the mass of atmospheric water substance becomes conserved, and the tempospatial distributions of water vapor, hydrometeors/cloud water, and precipitation are consistent with observations. (3) Diagnostic values of the difference in the transition between hydrometeors and water vapor (Cvh − Chv) and the surface evaporation (Es) are well consistent with their numerical values. (4) Correlation and bias analyses show that the diagnostic CWR contributors are well correlated with observations, and match their numerical counterparts as well, indicating that the CWR-NQ and CWR-DQ methods are reasonable. (5) Underestimation of water vapor converted from hydrometeors (Chv) is a shortcoming of the CWR-DQ method, which may be rectified by numerical quantification results or by use of advanced observations on higher spatiotemporal resolutions.
- Published
- 2020
62. Soil dissolved organic carbon in terrestrial ecosystems: Global budget, spatial distribution and controls
- Author
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Zhongmei Wan, Fenghui Yuan, Yunjiang Zuo, Jianzhao Liu, Xiaofeng Xu, Yihui Wang, Changchun Song, Yanyu Song, Liyuan He, Dan Li, Nannan Wang, and Ziyu Guo
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0106 biological sciences ,Total organic carbon ,Global and Planetary Change ,Ecology ,Soil texture ,010604 marine biology & hydrobiology ,Soil carbon ,010603 evolutionary biology ,01 natural sciences ,Tundra ,Environmental chemistry ,Dissolved organic carbon ,Soil water ,Environmental science ,Soil horizon ,Terrestrial ecosystem ,Ecology, Evolution, Behavior and Systematics - Abstract
AIMS: Soil dissolved organic carbon (DOC) is a primary form of labile carbon in terrestrial ecosystems, and therefore plays a vital role in soil carbon cycling. This study aims to quantify the budgets of soil DOC at biome and global levels and to examine the variations in soil DOC and their environmental controls. LOCATION: Global. TIME PERIOD: 1981–2019. METHODS: We compiled a global dataset and analysed the concentration and distribution of DOC across 10 biomes. RESULTS: Large variations in DOC are found among biomes across space and the soil DOC concentration declines exponentially along soil depths. Tundra has the highest soil DOC concentration in 0–30 cm soils [453.75 (95% confidence interval: 324.95–633.5) mg/kg], whereas tropical and temperate forests have relatively lower DOC concentrations, ranging from 30.20 (24.78–36.80) to 54.54 (49.77–59.77) mg/kg. DOC generally accounts for
- Published
- 2020
63. A metabolic labeling method detects m6A transcriptome-wide at single base resolution
- Author
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Xiao Shu, Zhike Lu, Yizhen Wang, Xinhua Feng, Mohan Cheng, Ting Li, Lijia Ma, Jianzhao Liu, Qing Dai, Xiaolong Cui, Jie Cao, Siying Xiang, Chuan He, Xiner Ying, Minsong Gao, Fengqin Wang, and Yanan Yue
- Subjects
0303 health sciences ,Messenger RNA ,Methionine ,Chemistry ,030302 biochemistry & molecular biology ,HEK 293 cells ,RNA ,Cell Biology ,Computational biology ,Methylation ,Reverse transcriptase ,Transcriptome ,03 medical and health sciences ,chemistry.chemical_compound ,Complementary DNA ,Molecular Biology ,030304 developmental biology - Abstract
Transcriptome-wide mapping of N6-methyladenosine (m6A) at base resolution remains an issue, impeding our understanding of m6A roles at the nucleotide level. Here, we report a metabolic labeling method to detect mRNA m6A transcriptome-wide at base resolution, called ‘m6A-label-seq’. Human and mouse cells could be fed with a methionine analog, Se-allyl-l-selenohomocysteine, which substitutes the methyl group on the enzyme cofactor SAM with the allyl. Cellular RNAs could therefore be metabolically modified with N6-allyladenosine (a6A) at supposed m6A-generating adenosine sites. We pinpointed the mRNA a6A locations based on iodination-induced misincorporation at the opposite site in complementary DNA during reverse transcription. We identified a few thousand mRNA m6A sites in human HeLa, HEK293T and mouse H2.35 cells, carried out a parallel comparison of m6A-label-seq with available m6A sequencing methods, and validated selected sites by an orthogonal method. This method offers advantages in detecting clustered m6A sites and holds promise to locate nuclear nascent RNA m6A modifications. The authors developed a metabolic labeling method via incorporation of allyl-SAM analogs to profile transcriptome-wide m6A at base resolution, which enables identification of m6A motifs and clustered m6A sites.
- Published
- 2020
64. m
- Author
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Xiao, Shu, Jie, Cao, and Jianzhao, Liu
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cell culture ,Adenosine ,sequence analysis ,molecular/chemical probes ,Protocol ,RNA ,molecular biology ,RNA, Messenger ,sequencing ,RNA-seq ,Transcriptome ,chemistry ,Methylation - Abstract
Summary We describe here a metabolic labeling protocol for detecting cellular transcriptome-wide mRNA N6-methyladenosine (m6A) at base resolution. By feeding cells an analog of methionine, potential mRNA m6A forming sites are replaced with the N6-allyladenosine (a6A). A mild chemical iodination of a6A in RNA results in its opposite base misincorporation during RNA reverse transcription, and thus m6A locations could be precisely identified in the high-throughput sequencing. m6A-label-seq provides a strategy to label and identify cellular epitranscriptomic modification sites. For complete details on the use and execution of this profile, please refer to Shu et al., 2020., Graphical abstract, Highlights • Detection of cellular mRNA m6A modification sites at single base resolution • m6A-forming site labeling via an allyl-substituted methyltransferase cofactor • Replacement of RNA m6A by N6-allyl adenosine via RNA metabolism • N6-allyl adenosine is a chemical sequencing nucleoside analog, We describe here a metabolic labeling protocol for detecting cellular transcriptome-wide mRNA N6-methyladenosine (m6A) at base resolution. By feeding cells an analog of methionine, potential mRNA m6A forming sites are replaced with the N6-allyladenosine (a6A). A mild chemical iodination of a6A in RNA results in its opposite base misincorporation during RNA reverse transcription, and thus m6A locations could be precisely identified in the high-throughput sequencing. m6A-label-seq provides a strategy to label and identify cellular epitranscriptomic modification sites.
- Published
- 2022
65. Microbial mechanisms for methane source-to-sink transition after wetland conversion to cropland
- Author
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Nannan Wang, Xinhao Zhu, Yunjiang Zuo, Jianzhao Liu, Fenghui Yuan, Ziyu Guo, Lihua Zhang, Ying Sun, Chao Gong, Dufa Guo, Changchun Song, and Xiaofeng Xu
- Subjects
History ,Polymers and Plastics ,Soil Science ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2023
66. A multifunctional piperazine-modified tetraphenylethene derivative: Hazardous chemical detection and lysosome-targeted cell imaging
- Author
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Juechen Ni, Xiao Shu, Jianzhao Liu, and Jing Zhi Sun
- Subjects
Biophysics ,General Chemistry ,Condensed Matter Physics ,Biochemistry ,Atomic and Molecular Physics, and Optics - Published
- 2022
67. N
- Author
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Xiaojie, Ma, Jie, Cao, Ziyu, Zhou, Yunkun, Lu, Qin, Li, Yan, Jin, Guo, Chen, Weiyun, Wang, Wenyan, Ge, Xi, Chen, Zhensheng, Hu, Xiao, Shu, Qian, Deng, Jiaqi, Pu, Chengzhen, Liang, Junfen, Fu, Jianzhao, Liu, and Saiyong, Zhu
- Subjects
Adenosine ,Organogenesis ,RNA Stability ,AlkB Homolog 5, RNA Demethylase ,Humans ,RNA, Messenger ,Transcription Factors - Abstract
Pancreatic differentiation from human pluripotent stem cells (hPSCs) provides promising avenues for investigating development and treating diseases. N
- Published
- 2021
68. ALKBH3-dependent m
- Author
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Wenjun, Kuang, Hao, Jin, Feng, Yang, Xiying, Chen, Jianzhao, Liu, Ting, Li, Yongxia, Chang, Min, Liu, Zhangqi, Xu, Chunxiao, Huo, Xiaoyi, Yan, Yuehong, Yang, Wei, Liu, Qiang, Shu, Shanshan, Xie, and Tianhua, Zhou
- Abstract
Primary cilia are antenna-like subcellular structures to act as signaling platforms to regulate many cellular processes and embryonic development. m
- Published
- 2021
69. Specific Targeting, Imaging, and Ablation of Tumor-Associated Macrophages by Theranostic Mannose–AIEgen Conjugates
- Author
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Xiaoying Gao, Fang Hu, Duo Mao, Jianzhao Liu, Bin Liu, Peng Zhang, Xingang Zuo, Jie Cao, Ben Zhong Tang, and Jing Zhi Sun
- Subjects
medicine.medical_treatment ,Mannose ,Photodynamic therapy ,010402 general chemistry ,Benzylidene Compounds ,01 natural sciences ,Theranostic Nanomedicine ,Analytical Chemistry ,Rats, Sprague-Dawley ,Mice ,chemistry.chemical_compound ,stomatognathic system ,medicine ,Animals ,Photosensitizer ,Tumor microenvironment ,Photosensitizing Agents ,Chemistry ,Macrophages ,010401 analytical chemistry ,Ablation ,0104 chemical sciences ,Photochemotherapy ,Tumor progression ,Mannosides ,Cancer research ,Mannose receptor ,Conjugate - Abstract
Tumor-associated macrophages (TAMs) that exist in tumor microenvironment promote tumor progression and have been suggested as a promising therapeutic target for cancer therapy in preclinical studies. Development of theranostic systems capable of specific targeting, imaging, and ablation of TAMs will offer clinical benefits. Here we constructed a theranostic probe, namely, TPE-Man, by attaching mannose moieties to a red-emissive and AIE (aggregation-induced emission)-active photosensitizer. TPE-Man can specifically recognize a mannose receptor that is overexpressed on TAMs by the sugar-receptor interaction and enables fluorescent visualization of the mannose-receptor-positive TAMs in high contrast. The histologic study of mouse tumor sections further verifies TPE-Man's excellent targeting specificity being comparable with the commercial mannose-receptor antibody. TAMs can be effectively eradicated upon exposure to white light irradiation via a photodynamic therapy effect. To our knowledge, this is the first small molecular theranostic probe for TAMs that revealed combined advantages of low cost, high targeting specificity, fluorescent light-up imaging, and efficient photodynamic ablation.
- Published
- 2019
70. Visualization and quantification of cellular RNA production and degradation using a combined fluorescence and mass spectrometry characterization assay
- Author
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Ben Zhong Tang, Xiaoying Gao, Yizhen Wang, Yinuo Song, Minsong Gao, Fengqin Wang, Jianzhao Liu, Jie Cao, Jing Zhi Sun, and Xiao Shu
- Subjects
RNA metabolism ,Chromatography ,010405 organic chemistry ,Chemistry ,Metals and Alloys ,RNA ,General Chemistry ,010402 general chemistry ,Mass spectrometry ,01 natural sciences ,Fluorescence ,Catalysis ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Characterization (materials science) ,Materials Chemistry ,Ceramics and Composites ,Degradation (geology) ,Linear correlation - Abstract
Here we report a combined fluorescence and mass spectrometry assay which is capable of stably visualizing and quantifying cellular nucleoside-labeled RNA production and degradation. The fluorescence and mass spectrometry signals from cellular labeled RNAs show a linear correlation. This simple and robust assay benefits the biological community to study RNA metabolism.
- Published
- 2019
71. Wetland conversion to cropland alters the microbes along soil profiles and over seasons
- Author
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Xinhao Zhu, Fenghui Yuan, Liyuan He, Ziyu Guo, Nannan Wang, Yunjiang Zuo, Jianzhao Liu, Kexin Li, Yihui Wang, Ying Sun, Lihua Zhang, Changchun Song, Yanyu Song, Chao Gong, Yowhan Son, Dufa Guo, and Xiaofeng Xu
- Subjects
Earth-Surface Processes - Published
- 2022
72. Circadian Clock Regulation of Hepatic Lipid Metabolism by Modulation of m6A mRNA Methylation
- Author
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Xiaorong Zhu, Nathaniel Hubert, Tian Wang, Jianzhao Liu, Jiayao Yu, Eugene B. Chang, Xiang Zhong, Vanessa Leone, Chuan He, Yong Huang, Fanfei Lin, Kyle T. Dolan, Xiaocheng Weng, Yi Li, Yun Tao, Candace M. Cham, Kristina Martinez-Guryn, and Katya Frazier
- Subjects
0301 basic medicine ,Adenosine ,Time Factors ,RNA methylation ,RNA Stability ,Circadian clock ,Methylation ,Models, Biological ,Article ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Circadian Clocks ,Animals ,Humans ,PPAR alpha ,RNA, Messenger ,Circadian rhythm ,Post-transcriptional regulation ,lcsh:QH301-705.5 ,Cell Proliferation ,Mice, Knockout ,Gene knockdown ,Chemistry ,ARNTL Transcription Factors ,RNA-Binding Proteins ,Lipid metabolism ,Hep G2 Cells ,Methyltransferases ,Lipid Metabolism ,Cell biology ,030104 developmental biology ,Liver ,lcsh:Biology (General) ,MRNA methylation ,Reactive Oxygen Species ,Gene Deletion - Abstract
Summary: Transcriptional regulation of circadian rhythms is essential for lipid metabolic homeostasis, disruptions of which can lead to metabolic diseases. Whether N6-methyladenosine (m6A) mRNA methylation impacts circadian regulation of lipid metabolism is unclear. Here, we show m6A mRNA methylation oscillations in murine liver depend upon a functional circadian clock. Hepatic deletion of Bmal1 increases m6A mRNA methylation, particularly of PPaRα. Inhibition of m6A methylation via knockdown of m6A methyltransferase METTL3 decreases PPaRα m6A abundance and increases PPaRα mRNA lifetime and expression, reducing lipid accumulation in cells in vitro. Mechanistically, YTHDF2 binds to PPaRα to mediate its mRNA stability to regulate lipid metabolism. Induction of reactive oxygen species both in vitro and in vivo increases PPaRα transcript m6A levels, revealing a possible mechanism for circadian disruption on m6A mRNA methylation. These data show that m6A RNA methylation is important for circadian regulation of downstream genes and lipid metabolism, impacting metabolic outcomes. : Zhong et al. reveal that hepatic Bmal1 deletion changes m6A mRNA methylation, particularly of PPaRα. METTL3 or YTHDF2 knockdown affects PPaRα transcription and translation, impacting downstream lipid metabolism. These findings further reveal the overlap between circadian gene network disruption, mRNA m6A modifications, and metabolic state. Keywords: circadian clock, Bmal1, hepatic, lipid metabolism, ROS, m6A RNA methylation, post-transcriptional regulation, METTL3, YTHDF2, PPaRα
- Published
- 2018
73. A Mutation-Based Method for Pinpointing a DNA N
- Author
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Mohan, Cheng, Xiao, Shu, Jie, Cao, Minsong, Gao, Siying, Xiang, Fengqin, Wang, Yizhen, Wang, and Jianzhao, Liu
- Subjects
Base Sequence ,Mutation ,Base Pairing ,DNA Modification Methylases - Abstract
DNA N
- Published
- 2021
74. Synthetic modified messenger RNA for therapeutic applications
- Author
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Jianzhao Liu, Xinhua Feng, Minsong Gao, and Qingyi Zhang
- Subjects
COVID-19 Vaccines ,medicine.medical_treatment ,0206 medical engineering ,Biomedical Engineering ,02 engineering and technology ,Computational biology ,Review Article ,Biology ,Biochemistry ,Biomaterials ,Cancer immunotherapy ,Genome editing ,mRNA delivery ,Gene expression ,medicine ,Humans ,RNA, Messenger ,Therapeutic mRNA ,Molecular Biology ,Gene ,Messenger RNA ,SARS-CoV-2 ,RNA ,COVID-19 ,General Medicine ,021001 nanoscience & nanotechnology ,020601 biomedical engineering ,mRNA vaccines ,Synthetic modified mRNA ,Infectious disease (medical specialty) ,RNA base modifications ,Immunotherapy ,0210 nano-technology ,Reprogramming ,Biotechnology - Abstract
Synthetic modified messenger RNA (mRNA) has manifested great potentials for therapeutic applications such as vaccines and gene therapies, with the recent mRNA vaccines for global pandemic COVID-19 (corona virus disease 2019) attracting the tremendous attention. The chemical modifications and delivery vehicles of synthetic mRNAs are the two key factors for their in vivo therapeutic applications. Chemical modifications like nucleoside methylation endow the synthetic mRNAs with high stability and reduced stimulation of innate immunity. The development of scalable production of synthetic mRNA and efficient mRNA formulation and delivery strategies in recent years have remarkably advanced the field. It is worth noticing that we had limited knowledge on the roles of mRNA modifications in the past. However, the last decade has witnessed not only new discoveries of several naturally occurring mRNA modifications but also substantial advances in understanding their roles on regulating gene expression. It is highly necessary to reconsider the therapeutic system made by synthetic modified mRNAs and delivery vectors. In this review, we will mainly discuss the roles of various chemical modifications on synthetic mRNAs, briefly summarize the progresses of mRNA delivery strategies, and highlight some latest mRNA therapeutics applications including infectious disease vaccines, cancer immunotherapy, mRNA-based genetic reprogramming and protein replacement, mRNA-based gene editing. Statement of significance The development of synthetic mRNA drug holds great promise but lies behind small molecule and protein drugs largely due to the challenging issues regarding its stability, immunogenicity and potency. In the last 15 years, these issues have beensubstantially addressed by synthesizing chemically modified mRNA and developing powerful delivery systems; the mRNA therapeutics has entered an exciting new era begun with the approved mRNA vaccines for the COVID-19 infection disease. Here, we provide recent progresses in understanding the biological roles of various RNA chemical modifications, in developing mRNA delivery systems, and in advancing the emerging mRNA-based therapeutic applications, with the purpose to inspire the community to spawn new ideas for curing diseases., Graphical Abstract Image, graphical abstract
- Published
- 2021
75. Ferrocene-Decorated Hyperbranched Poly(aroxycarbonylphenylene)s: Synthesis, Light Refraction, Photopatterning and Precursor to Magnetic Ceramics
- Author
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Jim, Cathy K. W., Lam, Jacky W. Y., Qin, Anjun, Leung, Chris W. T., Jianzhao, Liu, Sung, Herman H. Y., Williams, Ian D., and Tang, Ben Zhong
- Published
- 2013
- Full Text
- View/download PDF
76. Electroluminescent Y
- Author
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Jing, Xu, Jianzhao, Liu, Li, Yang, Junqing, Liu, and Yang, Yang
- Abstract
Silicon-based Yb-doped Y
- Published
- 2020
77. Experimental research on the behavior of masonry walls reinforced with dry-connected steel plate frames under axial compression
- Author
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Kangkang Duan, Zhixin Zhang, Shuangyin Cao, Denghu Jing, Jianzhao Liu, and Yonghui Hou
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Brick ,Materials science ,business.industry ,Composite number ,Stiffness ,Building and Construction ,Structural engineering ,Masonry ,Cracking ,Buckling ,Mechanics of Materials ,Architecture ,medicine ,Bearing capacity ,medicine.symptom ,Safety, Risk, Reliability and Quality ,business ,Ductility ,Civil and Structural Engineering - Abstract
This paper conducted several experimental tests and theoretical analyses to present a comprehensive study on the behavior of dry-connected steel plate frame-reinforced brick walls under axial compression. One unreinforced brick wall, two brick walls reinforced with dry-connected steel plate frame, and one brick wall reinforced with steel strips were fabricated for axial compression tests. The experiments generally showed that steel plate frames effectively improved the structure's bearing capacity and axial stiffness and impeded its cracking. Increasing the thickness of steel plates further improved the bearing capacity but undermined the ductility of the composite wall. Besides, based on the buckling theory of steel plate and the existing calculation theory of masonry strength, this paper also proposed formulas for determining the bearing capacity of the composite wall. The calculations of formulas exhibited acceptable accuracy in comparison with the experimental results.
- Published
- 2022
78. Chelator-mediated biomimetic degradation of cellulose and chitin
- Author
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Yuan Zhu, Jianzhao Liu, Chao Wang, Barry Goodell, and Alan R. Esker
- Subjects
Chitin ,02 engineering and technology ,Polysaccharide ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Structural Biology ,Biomimetic Materials ,Enzymatic hydrolysis ,Cellulose ,Molecular Biology ,030304 developmental biology ,Chelating Agents ,chemistry.chemical_classification ,0303 health sciences ,Depolymerization ,Regenerated cellulose ,General Medicine ,Quartz crystal microbalance ,021001 nanoscience & nanotechnology ,chemistry ,Chemical engineering ,Degradation (geology) ,0210 nano-technology - Abstract
Non-enzymatic degradation of wood via a chelator-mediated Fenton (CMF) system is the primary method for initial attack in brown rot fungal decomposition of wood, the most common type of fungal degradation of terrestrial carbon biomass on the planet. In this study, the degradation of thin films of cellulose and chitin by a CMF system was investigated and compared to enzymatic hydrolysis. The kinetics of the rapid cellulose and chitin deconstruction and the morphologies of the degraded cellulose and chitin surfaces were studied by quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM), respectively. The QCM-D results quantitatively indicated that ~90 wt% of the regenerated cellulose or chitin was capable of being deconstructed by CMF action alone. While enzymatic degradation was consistent with stripping of layers from the surface of the cellulose or chitin films, the CMF process exhibited a pronounced two stage process with a rapid initial depolymerization throughout the films. The initial degradation rates for both model surfaces by the CMF system were faster than enzyme action. This research suggests that the CMF process should be applicable for the deconstruction of a wide variety of polysaccharides over Fenton chemistry alone.
- Published
- 2020
79. Supplementary document for Electroluminescent Y3Al5O12 nanofilms fabricated by atomic layer deposition on silicon: Using Yb as the luminescent dopant and crystallization impetus - 4997191.pdf
- Author
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Xu, Jing, Jianzhao Liu, Yang, Li, Junqing Liu, and Yang, Yang
- Abstract
Supplementary Figures
- Published
- 2020
- Full Text
- View/download PDF
80. FAN: Frequency Aggregation Network for Real Image Super-Resolution
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Zhibo Chen, Yingxue Pang, Xin Jin, Jianzhao Liu, Yaojun Wu, Sen Liu, and Xin Li
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Channel (digital image) ,Computer science ,business.industry ,Deep learning ,020206 networking & telecommunications ,02 engineering and technology ,Residual ,Real image ,Superresolution ,Image (mathematics) ,Feature (computer vision) ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Computer vision ,Artificial intelligence ,Single image ,business - Abstract
Single image super-resolution (SISR) aims to recover the high-resolution (HR) image from its low-resolution (LR) input image. With the development of deep learning, SISR has achieved great progress. However, It is still a challenge to restore the real-world LR image with complicated authentic degradations. Therefore, we propose FAN, a frequency aggregation network, to address the real-world image super-resolu-tion problem. Specifically, we extract different frequencies of the LR image and pass them to a channel attention-grouped residual dense network (CA-GRDB) individually to output corresponding feature maps. And then aggregating these residual dense feature maps adaptively to recover the HR image with enhanced details and textures. We conduct extensive experiments quantitatively and qualitatively to verify that our FAN performs well on the real image super-resolution task of AIM 2020 challenge. According to the released final results, our team SR-IM achieves the fourth place on the X4 track with PSNR of 31.1735 and SSIM of 0.8728.
- Published
- 2020
81. m6A mRNA methylation regulates AKT activity to promote the proliferation and tumorigenicity of endometrial cancer
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Chuan He, Jianzhao Liu, Ying Yang, Jing-Tao Huang, Xiao-Hua Leng, Bryan T. Harada, Zhi-Gao Xu, Xue-Chen Yu, Song-Mei Liu, Samantha M. Tienda, Jie Cao, Shao-Min Chen, Zezhou Zhang, Kangkang Yu, Agnieszka Chryplewicz, Allen Zhu, Zhike Lu, Mark A. Eckert, Jun Liu, and Ernst Lengyel
- Subjects
0301 basic medicine ,Adenosine ,Time Factors ,Carcinogenesis ,Cellular differentiation ,Mice, Nude ,Mechanistic Target of Rapamycin Complex 2 ,Biology ,medicine.disease_cause ,Methylation ,Article ,03 medical and health sciences ,Cell Line, Tumor ,medicine ,Phosphoprotein Phosphatases ,Animals ,Humans ,RNA, Messenger ,RNA, Neoplasm ,RNA Processing, Post-Transcriptional ,Protein kinase B ,PI3K/AKT/mTOR pathway ,Cell Proliferation ,Regulation of gene expression ,Methyltransferase complex ,Cell Biology ,Methyltransferases ,3. Good health ,Cell biology ,Endometrial Neoplasms ,Tumor Burden ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,Mutation ,Female ,MRNA methylation ,Proto-Oncogene Proteins c-akt ,Signal Transduction - Abstract
N6-methyladenosine (m6A) messenger RNA methylation is a gene regulatory mechanism affecting cell differentiation and proliferation in development and cancer. To study the roles of m6A mRNA methylation in cell proliferation and tumorigenicity, we investigated human endometrial cancer in which a hotspot R298P mutation is present in a key component of the methyltransferase complex (METTL14). We found that about 70% of endometrial tumours exhibit reductions in m6A methylation that are probably due to either this METTL14 mutation or reduced expression of METTL3, another component of the methyltransferase complex. These changes lead to increased proliferation and tumorigenicity of endometrial cancer cells, likely through activation of the AKT pathway. Reductions in m6A methylation lead to decreased expression of the negative AKT regulator PHLPP2 and increased expression of the positive AKT regulator mTORC2. Together, these results reveal reduced m6A mRNA methylation as an oncogenic mechanism in endometrial cancer and identify m6A methylation as a regulator of AKT signalling.
- Published
- 2018
82. Preparation and enhanced structural integrity of electrospun poly(ε-caprolactone)-based fibers by freezing amorphous chains through thiol-ene click reaction
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Jizhou Fan, Zhiqiang Yang, Ruirui Xing, Qiuming Peng, Jingxin Zhou, Jianzhao Liu, Tifeng Jiao, Bingbing Li, and Yamei Liu
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Materials science ,Composite number ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Pentaerythritol ,Electrospinning ,0104 chemical sciences ,chemistry.chemical_compound ,Surface coating ,Colloid and Surface Chemistry ,chemistry ,Polymer chemistry ,Click chemistry ,Fiber ,0210 nano-technology ,Caprolactone ,Ene reaction - Abstract
Facile preparation and UV stabilization of electrospun poly(e-caprolactone) (PCL)/2-methyl-3-(trimethoxysilyl) propylester (M8POSS)/pentaerythritol tetrakis(3-mercaptopropionate) (PETM) composite fibers via thiol-ene click reaction were investigated. The morphological studies clearly showed the M8POSS and PETM macromers were excluded from PCL crystalline phase during electrospinning. The cross-linking reaction occurs in the amorphous phase of PCL fibers and possibly the fiber surface. By locking amorphous PCL chains into the cross-linked M8POSS and PETM through thiol-ene click reaction, we are able to fabricate PCL/POSS composite fibers, which can remain structural stability under UVC for longer period of time. The facile fabrication of the composite fibers via thiol-ene click reaction reported here provided valuable insight into not only the surface coating of medical devices but also new biocompatible composite materials.
- Published
- 2018
83. VIRMA mediates preferential m6A mRNA methylation in 3′UTR and near stop codon and associates with alternative polyadenylation
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Xiao Shu, Zezhou Zhang, Yizhen Wang, Minsong Gao, Guan-Zheng Luo, Honghui Ma, Tao Cheng, Xinxia Wang, Xinhua Feng, Jun Liu, Xiaolong Cui, Yanan Yue, Fengqin Wang, Jie Cao, Bin Shen, Jianzhao Liu, and Chuan He
- Subjects
0301 basic medicine ,Messenger RNA ,Cleavage factor ,Polyadenylation ,Chemistry ,Methyltransferase complex ,Three prime untranslated region ,lcsh:Cytology ,Cell Biology ,Biochemistry ,Stop codon ,Cell biology ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Genetics ,MRNA methylation ,N6-Methyladenosine ,lcsh:QH573-671 ,Molecular Biology - Abstract
N6-methyladenosine (m6A) is enriched in 3′untranslated region (3′UTR) and near stop codon of mature polyadenylated mRNAs in mammalian systems and has regulatory roles in eukaryotic mRNA transcriptome switch. Significantly, the mechanism for this modification preference remains unknown, however. Herein we report a characterization of the full m6A methyltransferase complex in HeLa cells identifying METTL3/METTL14/WTAP/VIRMA/HAKAI/ZC3H13 as the key components, and we show that VIRMA mediates preferential mRNA methylation in 3′UTR and near stop codon. Biochemical studies reveal that VIRMA recruits the catalytic core components METTL3/METTL14/WTAP to guide region-selective methylations. Around 60% of VIRMA mRNA immunoprecipitation targets manifest strong m6A enrichment in 3′UTR. Depletions of VIRMA and METTL3 induce 3′UTR lengthening of several hundred mRNAs with over 50% targets in common. VIRMA associates with polyadenylation cleavage factors CPSF5 and CPSF6 in an RNA-dependent manner. Depletion of CPSF5 leads to significant shortening of 3′UTR of over 2800 mRNAs, 84% of which are modified with m6A and have increased m6A peak density in 3′UTR and near stop codon after CPSF5 knockdown. Together, our studies provide insights into m6A deposition specificity in 3′UTR and its correlation with alternative polyadenylation.
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- 2018
84. Insights into CO2 adsorption and chemical fixation properties of VPI-100 metal–organic frameworks
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Wenqian Xu, Jianzhao Liu, Brittany L. Bonnett, Matthew C. Kessinger, Jie Zhu, Yered Machain, Diego Troya, Alan R. Esker, Pavel M. Usov, Shaoyang Lin, Sanjaya D. Senanayake, Meng Cai, and Amanda J. Morris
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Materials science ,Renewable Energy, Sustainability and the Environment ,02 engineering and technology ,General Chemistry ,Quartz crystal microbalance ,Crystal structure ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Catalysis ,Adsorption ,Chemical engineering ,Molecule ,General Materials Science ,Metal-organic framework ,Lewis acids and bases ,Isostructural ,0210 nano-technology - Abstract
Metal–organic frameworks (MOFs) have shown great promise as efficient CO2 adsorbents, as well as an emerging class of heterogeneous catalysts for conversion of CO2 to other useful chemicals. In this work, we synthesized and characterized two isostructural hafnium-based MOFs, denoted as Hf-VPI-100 (Cu) and Hf-VPI-100 (Ni). Both frameworks demonstrated high catalytic efficiency for cycloaddition of CO2 to epoxides under ambient pressure. In situ PXRD, QCM and DRIFTs have been used to probe the interaction between the guest molecules (CO2/epoxide) and Hf-VPI-100. The crystal structures of these frameworks were preserved during the exposure to CO2 atmosphere up to 20 bar. The epoxide uptake per unit cell of VPI-100 and diffusion coefficients have been calculated by QCM analysis. Comparison of catalytic efficiency between Hf-VPI-100 and the previously reported Zr-based VPI-100, aided by electronic structure calculations revealed that the open metal centers in the metallocyclam act as the primary Lewis acid sites to facilitate the catalytic conversion of CO2.
- Published
- 2018
85. Biochromic silole derivatives: a single dye for differentiation, quantitation and imaging of live/dead cells
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Engui Zhao, Yuning Hong, Shouxiang Zhang, Sijie Chen, Chris Y. Y. Yu, Roozbeh Hushiarian, Jianzhao Liu, and Ben Zhong Tang
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0301 basic medicine ,medicine.diagnostic_test ,Chemistry ,Process Chemistry and Technology ,010402 general chemistry ,01 natural sciences ,Fluorescence ,3. Good health ,0104 chemical sciences ,Flow cytometry ,03 medical and health sciences ,030104 developmental biology ,Mechanics of Materials ,Fluorescence microscope ,Biophysics ,medicine ,General Materials Science ,Viability assay ,Electrical and Electronic Engineering ,Red fluorescence - Abstract
Differentiating between live and dead cells is a critical step for biological researchers, clinical doctors and pharmaceutical engineers when evaluating cell viability, for determining compound cytotoxicity and in the development of effective treatments for many diseases. Usually, careful selection and combination of two different dyes are required to differentiate and image both live and dead cells. In this work, we present a new method that can differentiate, quantify and image both live and dead cells concurrently through the use of a single, cell-permeable, biochromic fluorescent dye. Two silole-based hemicyanine dyes, Silo-Cy and Silo-2Cy are designed and synthesized. These dyes exhibit green fluorescence in both live and dead cells but much stronger green and red fluorescence only from dead cells. By collecting signals from the two distinct channels, we are able to image and discriminate between live and dead cells through fluorescence microscopy and quantify the cell viability via flow cytometry.
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- 2018
86. A unimolecular theranostic system with H2O2-specific response and AIE-activity for doxorubicin releasing and real-time tracking in living cells
- Author
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Jianzhao Liu, Jie Cao, Bin Liu, Jing Zhi Sun, Xiaoying Gao, Yinuo Song, Ben Zhong Tang, and Xiao Shu
- Subjects
inorganic chemicals ,Drug ,Chemistry ,General Chemical Engineering ,media_common.quotation_subject ,Cell ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,medicine.anatomical_structure ,Cancer cell ,Drug delivery ,polycyclic compounds ,Cancer research ,medicine ,Doxorubicin ,0210 nano-technology ,Real time tracking ,media_common ,medicine.drug - Abstract
A theranostic drug delivery system composed of tetraphenyl-ethene (AIEgen), benzyl boronic ester (trigger), and doxorubicin (drug) was designed and synthesized; its utilities for cell imaging, drug delivery tracking, and cancer cell cytociding were evaluated.
- Published
- 2018
87. Experimental research on the shear behavior of brick walls reinforced with dry-connected steel plate frames
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Kangkang Duan, Shuangyin Cao, Denghu Jing, Zhixin Zhang, Jianzhao Liu, and Yonghui Hou
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Brick ,Materials science ,business.industry ,Stiffness ,Structural engineering ,Masonry ,Shear (sheet metal) ,Cracking ,Buckling ,medicine ,Bearing capacity ,medicine.symptom ,Ductility ,business ,Civil and Structural Engineering - Abstract
This paper conducted experimental tests and theoretical analyses to present a comprehensive study on the shear behavior of dry-connected steel plate frame-reinforced brick walls. One unreinforced brick wall, one brick wall reinforced with steel strips, and four brick walls reinforced with dry-connected steel plate frames were fabricated for shear compression tests. Experimental tests showed that steel plate frames effectively improved the bearing capacity and stiffness of masonry structures and impeded cracking. As expected, enhancing the steel plate thickness and vertical load boosted the peak load and axial stiffness of steel frame-reinforced structures but also reduced the ductility. Numerical simulation accurately predicted the peak load, crack development, and crushing area of the specimens. In addition, based on the buckling theory of steel plates and the existing calculation theory of masonry, this paper also proposed formulas for determining the bearing capacity of composite walls. The calculations of the formulas exhibited high accuracy in comparison with the experimental results.
- Published
- 2021
88. Divergent impacts of atmospheric water demand on gross primary productivity in three typical ecosystems in China
- Author
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Jianzhao Liu, Xianwei Wang, Xiaofeng Xu, Ning Chen, Li Sun, Ke Huang, Nan Cong, Peng Jiang, Mingjie Xu, Jiaxing Zu, Tao Zhang, Yunjiang Zuo, Zhipeng Wang, Yanyu Song, Peipei Jiang, and Changchun Song
- Subjects
Atmospheric Science ,Global and Planetary Change ,geography ,geography.geographical_feature_category ,Vapour Pressure Deficit ,Eddy covariance ,Forestry ,Atmospheric sciences ,Grassland ,Shrubland ,Forest ecology ,Soil water ,medicine ,Environmental science ,Dryness ,Ecosystem ,medicine.symptom ,Agronomy and Crop Science - Abstract
Atmospheric water demand is practically characterized as vapor pressure deficit (VPD) and has been identified as a critical driver of ecosystem function, by affecting plant mortality, wildfires, and carbon loss. In this study, we used daily eddy covariance data across Chinese forest, grassland and shrubland ecosystems, in combination with remote sensing data, to investigate the impacts of VPD on gross primary productivity (GPP). We found divergent VPD impacts on GPP among grassland, shrubland and forest ecosystems. The VPD yielded substantial inhibitory impacts on GPP in grassland ecosystems and this suppressing impact was regulated by soil water content (SWC), showing that GPP declined with VPD under dry conditions but increased with VPD under wet conditions. This GPP variance was attributed to VPD, SWC and their interactions. More than 50% of the variability in GPP was explained by SWC in grassland ecosystems and by VPD in forest and shrubland ecosystems. Partial correlation analysis, random forest, and multiple linear regression revealed similar results when temperature, radiation and SWC were considered. Compared with shrubland and forest ecosystems, grassland has drier environmental conditions and poorer soil water-holding capacity that led to lower SWC and stronger negative impacts on VPD. Thus, GPP was susceptible to the negative impacts of higher VPD, especially under dryness stress. Our results highlight the need to comprehensively consider divergent VPD impacts for different ecosystems to more accurately assess climate impacts on ecosystem function.
- Published
- 2021
89. Wetland reclamation homogenizes microbial properties along soil profiles
- Author
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Jianzhao Liu, Xiaofeng Xu, Xinhao Zhu, Yunjiang Zuo, Yanyu Song, Fenghui Yuan, Dufa Guo, Yihui Wang, Ying Sun, Ziyu Guo, Changchun Song, Nannan Wang, Liyuan He, Jielu Yu, and Lihua Zhang
- Subjects
Biomass (ecology) ,geography ,geography.geographical_feature_category ,food and beverages ,Soil Science ,Wetland ,04 agricultural and veterinary sciences ,Soil carbon ,010501 environmental sciences ,complex mixtures ,01 natural sciences ,Sanjiang Plain ,Microbial population biology ,Agronomy ,Land reclamation ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Soil horizon ,0105 earth and related environmental sciences - Abstract
Wetlands store approximately one-third of soil carbon (C) in terrestrial ecosystems, and the loss of C in wetlands has been accelerated by reclamation. However, how wetland reclamation affects microbial properties along soil profiles remains unclear. In this study, we sampled 100 cm soil cores from a wetland and an adjacent cropland that has been cultivated for 23 years to evaluate the impacts of land conversion on soil microbial community structure and soil element concentrations in the Sanjiang Plain, Northeastern China. The C and nitrogen (N) concentrations in microbial biomass declined exponentially with depth in both the wetland and cropland with different magnitudes. Continuous cultivation for 23 years tended to homogenized C, N, phosphorus (P), and sulfur (S) contents in soils and microbial biomass along the soil profile. Compared with the wetland, C and N in cropland soils were lower, and microbial biomass C, N, P and S were lower in surface soils (0–30 cm), while higher in both middle soils (40–70 cm) and deep soils (70–100 cm). Cultivation narrowed the C:N:P:S stoichiometry in soils and microbial biomass, with large changes in surface soils and minor changes in deep soils. The Bray-Curtis dissimilarity test confirmed the large changes in surface soils while minor changes in deep soils. After 23-years of cultivation the abundances of fungi and bacteria were significantly reduced by approximately 90% and 78% in surface soils, but the bacterial abundance was enhanced by approximately 2–3 times in middle soils, leading to a decreasing fungi:bacteria ratio along soil profile in cropland. Soil TC and pH were the predominant factors controlling the microbial composition in wetland. The homogenizing impact of wetland reclamation on microbial properties along soil profiles suggests the different responses of microbial and soil elements to human activities, indicating a critical need of differentiating microbes from soils when examining soil elements under a changing environment.
- Published
- 2021
90. Targeted Manipulation of Cellular RNA m6A Methylation at the Single-Base Level.
- Author
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Minsong Gao, Shichen Su, Jie Cao, Siying Xiang, Ye Huang, Xiao Shu, Jinbiao Ma, and Jianzhao Liu
- Published
- 2022
- Full Text
- View/download PDF
91. Comparative Analysis of Two Machine Learning Algorithms in Predicting Site-Level Net Ecosystem Exchange in Major Biomes
- Author
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Xiaofeng Xu, Fenghui Yuan, Yuedong Guo, Ziyu Guo, Yunjiang Zuo, Jingwei Zhang, Xia Song, Changchun Song, Lihua Zhang, Nannan Wang, Jianzhao Liu, Xinhao Zhu, and Ying Sun
- Subjects
010504 meteorology & atmospheric sciences ,Science ,Biome ,Climate change ,010501 environmental sciences ,Machine learning ,computer.software_genre ,01 natural sciences ,FluxNet ,terrestrial ecosystem ,Forest ecology ,machine learning ,NEE ,random forest ,XGBoost ,medicine ,Ecosystem ,Extreme Cold ,0105 earth and related environmental sciences ,business.industry ,General Earth and Planetary Sciences ,Dryness ,Environmental science ,Terrestrial ecosystem ,Artificial intelligence ,medicine.symptom ,business ,Algorithm ,computer - Abstract
The net ecosystem CO2 exchange (NEE) is a critical parameter for quantifying terrestrial ecosystems and their contributions to the ongoing climate change. The accumulation of ecological data is calling for more advanced quantitative approaches for assisting NEE prediction. In this study, we applied two widely used machine learning algorithms, Random Forest (RF) and Extreme Gradient Boosting (XGBoost), to build models for simulating NEE in major biomes based on the FLUXNET dataset. Both models accurately predicted NEE in all biomes, while XGBoost had higher computational efficiency (6~62 times faster than RF). Among environmental variables, net solar radiation, soil water content, and soil temperature are the most important variables, while precipitation and wind speed are less important variables in simulating temporal variations of site-level NEE as shown by both models. Both models perform consistently well for extreme climate conditions. Extreme heat and dryness led to much worse model performance in grassland (extreme heat: R2 = 0.66~0.71, normal: R2 = 0.78~0.81; extreme dryness: R2 = 0.14~0.30, normal: R2 = 0.54~0.55), but the impact on forest is less (extreme heat: R2 = 0.50~0.78, normal: R2 = 0.59~0.87; extreme dryness: R2 = 0.86~0.90, normal: R2 = 0.81~0.85). Extreme wet condition did not change model performance in forest ecosystems (with R2 changing −0.03~0.03 compared with normal) but led to substantial reduction in model performance in cropland (with R2 decreasing 0.20~0.27 compared with normal). Extreme cold condition did not lead to much changes in model performance in forest and woody savannas (with R2 decreasing 0.01~0.08 and 0.09 compared with normal, respectively). Our study showed that both models need training samples at daily timesteps of >2.5 years to reach a good model performance and >5.4 years of daily samples to reach an optimal model performance. In summary, both RF and XGBoost are applicable machine learning algorithms for predicting ecosystem NEE, and XGBoost algorithm is more feasible than RF in terms of accuracy and efficiency.
- Published
- 2021
92. Selenium and Selenium–Sulfur Chemistry for Rechargeable Lithium Batteries: Interplay of Cathode Structures, Electrolytes, and Interfaces
- Author
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Rachid Amine, Jianzhao Liu, Khalil Amine, Gui-Liang Xu, and Zonghai Chen
- Subjects
inorganic chemicals ,Battery (electricity) ,Inorganic chemistry ,Energy Engineering and Power Technology ,chemistry.chemical_element ,02 engineering and technology ,Electrolyte ,010402 general chemistry ,01 natural sciences ,law.invention ,law ,Materials Chemistry ,Dissolution ,Renewable Energy, Sustainability and the Environment ,021001 nanoscience & nanotechnology ,Sulfur ,Cathode ,0104 chemical sciences ,Fuel Technology ,chemistry ,Chemical engineering ,Chemistry (miscellaneous) ,Energy density ,Lithium ,0210 nano-technology ,Selenium - Abstract
In the search for a transformative new energy storage system, the rechargeable Li/sulfur battery is considered as one of the promising candidates due to its much higher energy density and lower cost than state-of-the-art lithium-ion batteries. However, the insulating nature of sulfur and the dissolution of intermediary polysulfides into the electrolyte significantly hinder its practical application. Very recently, selenium and selenium–sulfur systems have received considerable attention as cathode materials for rechargeable batteries owing to the high electronic conductivity (20 orders of magnitude higher than sulfur) and high volumetric capacity (3254 mAh/cm3) of selenium. In this Perspective, we present an overview of the implications of employing selenium and selenium–sulfur systems with different structures and compositions as electroactive materials for rechargeable lithium batteries. We also show how the cathode structures, electrolytes, and electrode–electrolyte interfaces affect the electrochemist...
- Published
- 2017
93. Insights into the structural effects of layered cathode materials for high voltage sodium-ion batteries
- Author
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Shi-Gang Sun, Khalil Amine, Ismael Saadoune, Tianyuan Ma, Xiaoyi Zhang, Yue-Feng Xu, Jihyeon Gim, Jianzhao Liu, Steve M. Heald, Rachid Amine, Abderrahim Solhy, Gui-Liang Xu, Yang Ren, Zonghai Chen, Cheng-Jun Sun, Wenjuan Liu Mattis, and Yuzi Liu
- Subjects
Battery (electricity) ,Diffraction ,Materials science ,Renewable Energy, Sustainability and the Environment ,High voltage ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Pollution ,Cathode ,0104 chemical sciences ,law.invention ,Nuclear Energy and Engineering ,Chemical engineering ,law ,Phase (matter) ,Forensic engineering ,Environmental Chemistry ,Thermal stability ,0210 nano-technology ,Power density - Abstract
Cathode materials are critical to the energy density, power density and safety of sodium-ion batteries (SIBs). Herein, we performed a comprehensive study to elucidate and exemplify the interplay mechanism between phase structures, interfacial microstrain and electrochemical properties of layered-structured NaxNi1/3Co1/3Mn1/3O2 cathode materials for high voltage SIBs. The electrochemical test results showed that NaxNi1/3Co1/3Mn1/3O2 with an intergrowth P2/O3/O1 structure demonstrates better electrochemical performance and better thermal stability than NaxNi1/3Co1/3Mn1/3O2 with P2/O3 binary-phase integration and NaxNi1/3Co1/3Mn1/3O2 where only the P phase is dominant. This result is caused by the distinct interfacial microstrain development during the synthesis and cycling of the P2/O3/O1 phase. In operando high energy X-ray diffraction further revealed that the intergrowth P2/O1/O3 cathode can inhibit the irreversible P2–O2 phase transformation and simultaneously improve the structure stability of the O3 and O1 phases during cycling. We believe that interfacial microstrain can serve as an indispensable bridge to guide future design and synthesis of high performance SIB cathode materials and other high energy battery materials.
- Published
- 2017
94. Climate Change Made Major Contributions to Soil Water Storage Decline in the Southwestern US during 2003–2014
- Author
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Yuedong Guo, Fenghui Yuan, Liping Gao, Jianzhao Liu, and Xiaofeng Xu
- Subjects
lcsh:Hydraulic engineering ,010504 meteorology & atmospheric sciences ,Geography, Planning and Development ,Climate change ,drought ,Aquatic Science ,010502 geochemistry & geophysics ,01 natural sciences ,Biochemistry ,Water consumption ,lcsh:Water supply for domestic and industrial purposes ,atmospheric water input ,lcsh:TC1-978 ,Evapotranspiration ,Precipitation ,0105 earth and related environmental sciences ,Water Science and Technology ,lcsh:TD201-500 ,Southwest US ,Water storage ,water storage ,Arid ,climate change ,Soil water ,Period (geology) ,Environmental science ,Physical geography - Abstract
Soil water shortage is a critical issue for the Southwest US (SWUS), the typical arid region that has experienced severe droughts over the past decades, primarily caused by climate change. However, it is still not quantitatively understood how soil water storage in the SWUS is affected by climate change. We integrated the time-series data of water storage and evapotranspiration derived from satellite data, societal water consumption, and meteorological data to quantify soil water storage changes and their climate change impacts across the SWUS from 2003 to 2014. The water storage decline was found across the entire SWUS, with a significant reduction in 98.5% of the study area during the study period. The largest water storage decline occurred in the southeastern portion, while only a slight decline occurred in the western and southwestern portions of the SWUS. Net atmospheric water input could explain 38% of the interannual variation of water storage variation. The climate-change-induced decreases in net atmospheric water input predominately controlled the water storage decline in 60% of the SWUS (primarily in Texas, Eastern New Mexico, Eastern Arizona, and Oklahoma) and made a partial contribution in approximately 17% of the region (Central and Western SWUS). Climate change, primarily as precipitation reduction, made major contributions to the soil water storage decline in the SWUS. This study infers that water resource management must consider the climate change impacts over time and across space in the SWUS.
- Published
- 2019
- Full Text
- View/download PDF
95. The RNA binding protein FgRbp1 regulates specific pre-mRNA splicing via interacting with U2AF23 in Fusarium
- Author
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Zhonghua Ma, Tianling Ma, Yun Chen, Won-Bo Shim, Minhui Wang, Haixia Wang, and Jianzhao Liu
- Subjects
0106 biological sciences ,0301 basic medicine ,Science ,RNA Splicing ,Regulator ,General Physics and Astronomy ,RNA-binding protein ,Plasma protein binding ,Biology ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Fungal Proteins ,03 medical and health sciences ,Splicing factor ,Fusarium ,RNA Precursors ,Humans ,RNA, Messenger ,Gene ,Messenger RNA ,Multidisciplinary ,Binding Sites ,Base Sequence ,Virulence ,food and beverages ,RNA ,RNA-Binding Proteins ,General Chemistry ,Splicing Factor U2AF ,Introns ,Cell biology ,030104 developmental biology ,RNA splicing ,RNA Splice Sites ,Edible Grain ,010606 plant biology & botany ,Protein Binding - Abstract
Precursor messenger RNA (pre-mRNA) splicing is an essential and tightly regulated process in eukaryotic cells; however, the regulatory mechanisms for the splicing are not well understood. Here, we characterize a RNA binding protein named FgRbp1 in Fusarium graminearum, a fungal pathogen of cereal crops worldwide. Deletion of FgRbp1 leads to reduced splicing efficiency in 47% of the F. graminearum intron-containing gene transcripts that are involved in various cellular processes including vegetative growth, development, and virulence. The human ortholog RBM42 is able to fully rescue the growth defects of ΔFgRbp1. FgRbp1 binds to the motif CAAGR in its target mRNAs, and interacts with the splicing factor FgU2AF23, a highly conserved protein involved in 3’ splice site recognition, leading to enhanced recruitment of FgU2AF23 to the target mRNAs. This study demonstrates that FgRbp1 is a splicing regulator and regulates the pre-mRNA splicing in a sequence-dependent manner in F. graminearum. Human RBM42 associates with the spliceosome complex. Here the authors show that the fungus counterpart of RBM42, FgRbp1 regulates splicing by interacting with FgU2AF23.
- Published
- 2019
96. RNA m6A methylation regulates the epithelial mesenchymal transition of cancer cells and translation of Snail
- Author
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Guo-Shi Chai, Hong-Sheng Wang, Jianzhao Liu, Chuan He, Xinyao Lin, Shuibin Lin, Jun Du, Jiexin Li, Guan-Zheng Luo, Jordi Tauler, Feng Chen, and Yingmin Wu
- Subjects
0301 basic medicine ,Adenosine ,General Physics and Astronomy ,Kaplan-Meier Estimate ,02 engineering and technology ,Snail ,Metastasis ,Mice ,RNA Processing, Post-Transcriptional ,lcsh:Science ,Regulation of gene expression ,Mice, Inbred BALB C ,Multidisciplinary ,Liver Neoplasms ,RNA-Binding Proteins ,Translation (biology) ,021001 nanoscience & nanotechnology ,Up-Regulation ,Gene Expression Regulation, Neoplastic ,Liver ,Gene Knockdown Techniques ,Female ,0210 nano-technology ,Epithelial-Mesenchymal Transition ,Science ,Down-Regulation ,Mice, Nude ,Biology ,Methylation ,Article ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Downregulation and upregulation ,Cell Line, Tumor ,biology.animal ,medicine ,Animals ,Humans ,Cell migration ,Epithelial–mesenchymal transition ,Transcription factor ,Methyltransferases ,General Chemistry ,medicine.disease ,Xenograft Model Antitumor Assays ,030104 developmental biology ,Tissue Array Analysis ,Cancer cell ,Cancer research ,RNA ,lcsh:Q ,Snail Family Transcription Factors - Abstract
N6-Methyladenosine (m6A) modification has been implicated in the progression of several cancers. We reveal that during epithelial-mesenchymal transition (EMT), one important step for cancer cell metastasis, m6A modification of mRNAs increases in cancer cells. Deletion of methyltransferase-like 3 (METTL3) down-regulates m6A, impairs the migration, invasion and EMT of cancer cells both in vitro and in vivo. m6A-sequencing and functional studies confirm that Snail, a key transcription factor of EMT, is involved in m6A-regulated EMT. m6A in Snail CDS, but not 3’UTR, triggers polysome-mediated translation of Snail mRNA in cancer cells. Loss and gain functional studies confirm that YTHDF1 mediates m6A-increased translation of Snail mRNA. Moreover, the upregulation of METTL3 and YTHDF1 act as adverse prognosis factors for overall survival (OS) rate of liver cancer patients. Our study highlights the critical roles of m6A on regulation of EMT in cancer cells and translation of Snail during this process., RNA m6A methylation is known to be dysregulated in many cancers. Here, the authors show that m6A methylation of Snail mRNA regulates its translation with potential effects on epithelial mesenchymal transition.
- Published
- 2019
97. Investigating the Influence and a Potential Mechanism of Self-Compassion on Experimental Pain: Evidence From a Compassionate Self-Talk Protocol and Heart Rate Variability
- Author
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Xianwei Che, Xi Luo, and Jianzhao Liu
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Adult ,Male ,Arousal ,Nociceptive Pain ,03 medical and health sciences ,Electrocardiography ,Young Adult ,0302 clinical medicine ,Clinical Protocols ,030202 anesthesiology ,Heart Rate ,medicine ,Heart rate variability ,Humans ,Pain Management ,Potential mechanism ,Pain Measurement ,Protocol (science) ,business.industry ,Self-Management ,Perspective (graphical) ,Chronic pain ,Pain Perception ,medicine.disease ,Self Concept ,Anesthesiology and Pain Medicine ,Neurology ,Female ,Neurology (clinical) ,Empathy ,business ,030217 neurology & neurosurgery ,Self-compassion ,Intrapersonal communication ,Clinical psychology - Abstract
Previous studies have indicated a positive relationship between self-compassion and psychological and emotional well-being in chronic pain populations. However, evidence on the role and mechanisms of self-compassion in pain perception is largely limited. The current study was designed to investigate the effects and a potential mechanism of self-compassion on experimental pain. Thirty healthy participants underwent a compassionate self-talk protocol, which was followed by cold pain exposure during which high-frequency heart rate variability (HF-HRV) was evaluated. The compassionate self-talk protocol successfully generated compassionate statements among the participants. Our behavioral data showed lower pain ratings in the self-compassion compared to the control condition. Moreover, self-compassion manipulation resulted in higher HF-HRV during pain, which was associated with lower pain ratings. We present interesting findings that a short period of compassionate self-talk may decrease experimental pain as well as mechanistic evidence surrounding bodily control over pain-related arousal indicated by HF-HRV. PERSPECTIVE: This study presents the first line of evidence that a short period of compassionate self-talk may be sufficient to reduce experimental pain. We also demonstrate increased bodily control as a potential mechanism underlying this effect.
- Published
- 2018
98. Electroluminescent Y3Al5O12 nanofilms fabricated by atomic layer deposition on silicon: using Yb as the luminescent dopant and crystallization impetus
- Author
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Junqing Liu, jianzhao liu, Yang Yang, Li Yang, and Jing Xu
- Subjects
Materials science ,Silicon ,Dopant ,business.industry ,Annealing (metallurgy) ,Doping ,chemistry.chemical_element ,02 engineering and technology ,Electroluminescence ,021001 nanoscience & nanotechnology ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,law.invention ,010309 optics ,Atomic layer deposition ,Optics ,chemistry ,law ,0103 physical sciences ,Optoelectronics ,Crystallization ,0210 nano-technology ,business ,Luminescence - Abstract
Silicon-based Yb-doped Y3Al5O12 garnet nanofilms are fabricated by atomic layer deposition, which are polycrystalline after annealing at 1150 °C. The sub-nanometer compositional regulation and the Yb2O3 cladding layers, which also work as the luminescent dopants, are critical for the crystallization. Characteristic Yb3+ luminescence at 1030 nm and 970 nm is identified under electrical injection, exhibiting the external quantum efficiency of 0.65% and the fluorescence lifetime of 80-200 µs. The doped Yb3+ are impact-excited by hot electrons stemming from Fowler-Nordheim tunneling mechanism within the Y3Al5O12 matrix, with the excitation cross section of 0.7×10−15 to 6.4×10−15 cm2. This work certifies the manipulation of multi-oxide nanofilms with designed composition and crystallinity, revealing the possibility of developing Si-based optoelectronic devices from crystalline garnet films.
- Published
- 2020
99. Abundant DNA 6mA methylation during early embryogenesis of zebrafish and pig
- Author
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Dahua Chen, Xin Zong, Xinxia Wang, Jianzhao Liu, Chuan He, Dali Han, Yanan Yue, Guan-Zheng Luo, Ye Fu, Kai Chen, Yizhen Wang, Xiaona Wang, Hang Yin, and Yuanxiang Zhu
- Subjects
0301 basic medicine ,Swine ,Science ,General Physics and Astronomy ,Embryonic Development ,Eukaryotic DNA replication ,Biology ,Genome ,General Biochemistry, Genetics and Molecular Biology ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,Deoxyadenosine ,Animals ,Epigenetics ,Zebrafish ,Repetitive Sequences, Nucleic Acid ,Genetics ,Multidisciplinary ,Deoxyadenosines ,General Chemistry ,Methylation ,DNA ,DNA Methylation ,biology.organism_classification ,030104 developmental biology ,chemistry ,Prokaryotic DNA replication - Abstract
DNA N6-methyldeoxyadenosine (6mA) is a well-known prokaryotic DNA modification that has been shown to exist and play epigenetic roles in eukaryotic DNA. Here we report that 6mA accumulates up to ∼0.1–0.2% of total deoxyadenosine during early embryogenesis of vertebrates, but diminishes to the background level with the progression of the embryo development. During this process a large fraction of 6mAs locate in repetitive regions of the genome., DNA 6mA is a poorly understood epigenetic mark present at a low abundance in eukaryotic genomes. Here the authors observe high levels in zebrafish and pig during early embryogenesis enriched to repetitive regions of the genome and followed by attenuation during development.
- Published
- 2016
100. An Efficient, Regioselective Pathway to Cationic and Zwitterionic N-Heterocyclic Cellulose Ionomers
- Author
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Kevin J. Edgar, Shu Liu, Alan R. Esker, and Jianzhao Liu
- Subjects
Halogenation ,Polymers and Plastics ,Pyridines ,Salt (chemistry) ,Bioengineering ,02 engineering and technology ,010402 general chemistry ,Polysaccharide ,01 natural sciences ,Biomaterials ,chemistry.chemical_compound ,Heterocyclic Compounds ,Cations ,Pyridine ,Materials Chemistry ,Organic chemistry ,Cellulose ,chemistry.chemical_classification ,Biomolecule ,Imidazoles ,Cationic polymerization ,Acetylation ,021001 nanoscience & nanotechnology ,Cellulose acetate ,0104 chemical sciences ,Solvent ,Kinetics ,chemistry ,0210 nano-technology - Abstract
Cationic derivatives of cellulose and other polysaccharides are attractive targets for biomedical applications due to their propensity for electrostatically binding with anionic biomolecules, such as nucleic acids and certain proteins. To date, however, relatively few practical synthetic methods have been described for their preparation. Herein, we report a useful and efficient strategy for cationic cellulose ester salt preparation by the reaction of 6-bromo-6-deoxycellulose acetate with pyridine or 1-methylimidazole. Dimethyl sulfoxide solvent favored this displacement reaction to produce cationic cellulose acetate derivatives, resulting in high degrees of substitution (DS) exclusively at the C-6 position. These cationic cellulose derivatives bearing substantial, permanent positive charge exhibit surprising thermal stability, dissolve readily in water, and bind strongly with a hydrophilic and anionic surface, supporting their potential for a variety of applications such as permeation enhancement, mucoadhesion, and gene or drug delivery. Expanding upon this chemistry, we reacted a 6-imidazolyl-6-deoxycellulose derivative with 1,3-propane sultone to demonstrate the potential for further elaboration to regioselectively substituted zwitterionic cellulose derivatives.
- Published
- 2016
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