Publications by authors named "Xianyu Liu"

23 Publications

  • Page 1 of 1

Role of molecular size of volatile organic compounds on their adsorption by KOH-activated micro-mesoporous carbon.

J Hazard Mater 2021 Sep 29;424(Pt B):127355. Epub 2021 Sep 29.

Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou 310058, China; Zhejiang University-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311200, China. Electronic address:

KOH-activated carbon (KAC) with high surface area and abundant micropores are widely used in adsorbing volatile organic compounds (VOCs). Kinetic diameters (σ) of VOCs are an important factor controlling diffusion of VOCs into pores of adsorbent. Yet the influence of kinetic diameters of VOCs on their adsorption by KAC remains unclear. Here, we investigated the dynamic adsorption of VOCs with various kinetic diameters on a prepared KAC with high surface area of 3100 m/g, pore volume of 2.08 cm/g and average pore width (D) of 2.68 nm. Adsorption affinity was negatively correlated with size difference (D-σ), indicating that pore width of adsorbent should close to σ to obtain a strong interaction between VOCs and adsorbents. Amounts adsorbed were positively correlated with σ at low relative pressures (p/p < 0.01), and negatively correlated with σ at high relative pressures (p/p > 0.044). The above results suggest that larger molecules with higher affinities are preferentially adsorbed at low relative pressures, amounts adsorbed of smaller molecules are larger than that of bigger molecules at high relative pressures. This study provided new insights into adsorption mechanisms mediated by σ and the development of next generation adsorbents for efficient removal of VOCs.
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http://dx.doi.org/10.1016/j.jhazmat.2021.127355DOI Listing
September 2021

tRNA-derived small RNAs: novel regulators of cancer hallmarks and targets of clinical application.

Cell Death Discov 2021 Sep 18;7(1):249. Epub 2021 Sep 18.

Department of Thoracic Surgery, Xiangya Hospital, Central South University, Xiangya Road 87th, Changsha, 410008, Hunan, P. R. China.

tRNAs are a group of conventional noncoding RNAs (ncRNAs) with critical roles in the biological synthesis of proteins. Recently, tRNA-derived small RNAs (tsRNAs) were found to have important biological functions in the development of human diseases including carcinomas, rather than just being considered pure degradation material. tsRNAs not only are abnormally expressed in the cancer tissues and serum of cancer patients, but also have been suggested to regulate various vital cancer hallmarks. On the other hand, the application of tsRNAs as biomarkers and therapeutic targets is promising. In this review, we focused on the basic characteristics of tsRNAs, and their biological functions known thus far, and explored the regulatory roles of tsRNAs in cancer hallmarks including proliferation, apoptosis, metastasis, tumor microenvironment, drug resistance, cancer stem cell phenotype, and cancer cell metabolism. In addition, we also discussed the research progress on the application of tsRNAs as tumor biomarkers and therapeutic targets.
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http://dx.doi.org/10.1038/s41420-021-00647-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8449783PMC
September 2021

Scalable synthesis of 3D porous germanium encapsulated in nitrogen-doped carbon matrix as an ultra-long-cycle life anode for lithium-ion batteries.

Dalton Trans 2021 Oct 5;50(38):13476-13482. Epub 2021 Oct 5.

School of Chemistry and Chemical Engineering, Institute of Urban Ecology and Environment, Nanomaterials Laboratory, Lanzhou City University, Lanzhou, Gansu 730070, The People's Republic of China.

Germanium-based materials attract more interest as anodes for lithium-ion batteries, stemming from their physical and chemical advantages. However, these materials inevitably undergo capacity attenuation caused by significant volumetric variation in repeated electrochemical processes. Herein, we designed 3D porous Ge/N-doped carbon nanocomposites by the encapsulation of 3D porous Ge in a nitrogen-doped carbon matrix (denoted as 3D porous Ge/NC). The 3D porous structure can accommodate the volume change during alloying/dealloying processes and improve the penetration of the electrolyte. Furthermore, the doping of N in the carbon framework could introduce more defects and active sites, which can also contribute to electron transportation and lithium-ion diffusion. The half-cell test found that at a current density of 1 C (1 C = 1600 mA h g), the specific capacity stabilized at 917.9 mA h g after 800 cycles; and the specific capacity remained at 542.4 mA h g at 10 C. When assembled into a 3D porous Ge/NC//LiFePO full cell, the specific capacity was stabilized at 101.3 mA h g for 100 cycles at a current density of 1 C (1 C = 170 mA h g), and the cycle specific capacity was maintained at 72.6 mA h g at a high current density of 5 C. This work develops a low-cost, scalable and simple strategy to improve the electrochemical performance of these alloying type anode materials with huge volume change in the energy storage area.
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http://dx.doi.org/10.1039/d1dt00797aDOI Listing
October 2021

One-Pot Synthesis of High-Performance Tin Chalcogenides/C Anodes for Li-Ion Batteries.

ACS Omega 2021 Jul 30;6(27):17391-17399. Epub 2021 Jun 30.

Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China.

Tin chalcogenides are considered as promising anode materials for lithium-ion batteries (LIBs) due to their high theoretical lithium-storage capacity. Herein, we have successfully synthesized the composites of tin chalcogenides and graphite, that is, SnS/C, SnSe/C, and SnSSe/C, via a simple one-pot solid-state method. During the electrochemical test, they exhibit excellent lithium-storage ability and cyclic performance as the anode electrodes of LIBs due to the introduction of carbon. In particular, (i) SnS/C displayed a high specific capacity of 875 mAh g at 0.2 A g over 200 cycles; (ii) SnSe/C presents 734 mAh g at 0.2 A g after 100 cycles, and it delivers 690 mAh g at 1.0 A g over 300 cycles; and (iii) the SnSSe/C composite electrode delivers a specific capacity of 643 mAh g at 0.5 A g over 150 cycles. Furthermore, another series of tin-based composites have also been successfully fabricated (i.e., Sn/C, SnS/C, SnSe/C, and SnTe/C), showing the general applicability of the synthetic route applied here. Our synthetic approach demonstrates a promising route for the large-scale production of high-performance tin chalcogenides/C anode materials for LIBs and other battery systems (e.g., Na-ion and K-ion batteries).
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http://dx.doi.org/10.1021/acsomega.1c01647DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8280710PMC
July 2021

Facile Synthesis of MPS/C (M = Ni and Sn) Hybrid Materials and Their Application in Lithium-Ion Batteries.

ACS Omega 2021 Jul 29;6(27):17247-17254. Epub 2021 Jun 29.

Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China.

Herein, we successfully synthesized two novel metal thiophosphites (MTPs) hybridized with carbon, that is, NiPS/C and SnPS/C composites, via an environment-friendly and cost-effective approach without harsh reaction conditions. Subsequently, the electrochemical performances of NiPS/C and SnPS/C composites have been investigated in coin-cells, and it is revealed that MTPs/C have a significantly higher Li-storage capacity and better stability compared to the MTPs without carbon. Moreover, the SnPS/C electrode shows a lower internal resistance and a better rate performance compared to NiPS/C. We employed extensive ex situ experiments to characterize the materials and interpreted the remarkably improved performance of MTPs/C.
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http://dx.doi.org/10.1021/acsomega.1c01042DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8280674PMC
July 2021

Gene and Phenotype Expansion of Unexplained Early Infantile Epileptic Encephalopathy.

Front Neurol 2021 7;12:633637. Epub 2021 Jun 7.

Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China.

The genetic aetiology of epileptic encephalopathy (EE) is growing rapidly based on next generation sequencing (NGS) results. In this single-centre study, we aimed to investigate a cohort of Chinese children with early infantile epileptic encephalopathy (EIEE). NGS was performed on 50 children with unexplained EIEE. The clinical profiles of children with pathogenic variants were characterised and analysed in detail. Conservation analysis and homology modelling were performed to predict the impact of variant on the protein structure. Pathogenic variants were identified in 17 (34%) of 50 children. Sixteen variants including ( = 2), ( = 2), ( = 9), , and were , and one () was a compound heterozygous variant. The phenotypes of the identified genes were broadened. phenotypic spectrum may include EIEE. The variants were predicted to affect protein stability. NGS is a useful diagnostic tool for EIEE and contributes to expanding the EIEE-associated genotypes. Early diagnosis may lead to precise therapeutic interventions and can improve the developmental outcome.
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http://dx.doi.org/10.3389/fneur.2021.633637DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8215605PMC
June 2021

XBP1- IGFBP3 Signaling Pathway Promotes NSCLC Invasion and Metastasis.

Front Oncol 2021 18;11:654995. Epub 2021 May 18.

Department of Thoracic Surgery, Xiangya Hospital, Central South University, Changsha, China.

Lung cancer is the most frequently diagnosed cancer and the main cause of cancer death in the world. X-box binding protein 1 (XBP1), which is an important transcription factor involved in regulating the unfolded protein response (UPR) during endoplasmic reticulum (ER) stress, might act as a potent oncogenic protein in the processes of tumorigenesis, tumor proliferation and metastasis in various cancers. However, the clinical significance and pathological role of XBP1 in non-small cell lung cancer (NSCLC) remains unknown. In this study, we investigated the expression of XBP1s protein in the 104 NSCLC tumor tissues and matched adjacent normal lung tissues (ANLT) by Immunohistochemical (IHC), and we found overexpressed XBP1s protein was associated with NSCLC TNM stages, lymph node metastasis and poor prognosis. The further gain-and loss-of-function experiments indicated overexpression of XBP1s protein promoted cell invasion, migration and metastasis both and . Further study showed XBP1s protein could upregulate insulin-like growth factor binding protein-3 (IGFBP3) expression, and regulated NSCLC cells invasion and metastasis by regulating IGFBP3. Taken together, XBP1s protein is markedly overexpressed in NSCLC and serves as an oncogene that play a critical role in NSCLC tumorigenesis and development. Importantly, XBP1s protein might not only be a potential biomarker for metastasis and prognosis but also a potential therapeutic target in NSCLC.
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http://dx.doi.org/10.3389/fonc.2021.654995DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8169999PMC
May 2021

Vanadium Pentoxide Nanofibers/Carbon Nanotubes Hybrid Film for High-Performance Aqueous Zinc-Ion Batteries.

Nanomaterials (Basel) 2021 Apr 20;11(4). Epub 2021 Apr 20.

Institute of Materials and Technology, Dalian Maritime University, Dalian 116026, China.

Aqueous zinc-ion batteries (ZIBs) with the characteristics of low production costs and good safety have been regarded as ideal candidates for large-scale energy storage applications. However, the nonconductive and non-redox active polymer used as the binder in the traditional preparation of electrodes hinders the exposure of active sites and limits the diffusion of ions, compromising the energy density of the electrode in ZIBs. Herein, we fabricated vanadium pentoxide nanofibers/carbon nanotubes (VO/CNTs) hybrid films as binder-free cathodes for ZIBs. High ionic conductivity and electronic conductivity were enabled in the VO/CNTs film due to the porous structure of the film and the introduction of carbon nanotubes with high electronic conductivity. As a result, the batteries based on the VO/CNTs film exhibited a higher capacity of 390 mAh g at 1 A g, as compared to batteries based on VO (263 mAh g). Even at 5 A g, the battery based on the VO/CNTs film maintained a capacity of 250 mAh g after 2000 cycles with a capacity retention of 94%. In addition, the VO/CNTs film electrode also showed a high energy/power density (e.g., 67 kW kg/267 Wh kg). The capacitance response and rapid diffusion coefficient of Zn (~10 cm s) can explain the excellent rate capability of VO/CNTs. The vanadium pentoxide nanofibers/carbon nanotubes hybrid film as binder-free cathodes showed a high capability and a stable cyclability, demonstrating that it is highly promising for large-scale energy storage applications.
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http://dx.doi.org/10.3390/nano11041054DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8074388PMC
April 2021

PCDH19-Related Epilepsy in Early Onset of Chinese Male Patient: Case Report and Literature Review.

Front Neurol 2020 30;11:311. Epub 2020 Apr 30.

Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China.

Mutations in are associated with epilepsy, intellectual disability and behavioral disturbances, mostly related to females. The unique X-linked pattern of inheritance affects females predominantly, while usually is transmitted through asymptomatic males. Recently, new research has demonstrated that males with a mosaic pattern of inheritance could also be affected. As yet, mutations have been reported in hundreds of females; however, only 15 mosaic males were reported to exhibit epileptic seizures with the onset ranges between 6 and 31 months. These patients were usually reported to carry various mutations in the . Here we describe a non-sense variant at the (c.498C>G; p.Y166) in the Chinese male that exhibited early developmental delay and frequent seizures starting from the age of 5 months. We aim that this case report, focusing on studying clinical seizures, therapeutic approaches, and the patient's prognosis, will contribute to the cumulative knowledge of this rare and complex genetic disorder.
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http://dx.doi.org/10.3389/fneur.2020.00311DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7203462PMC
April 2020

Vasculogenic mimicry in carcinogenesis and clinical applications.

J Hematol Oncol 2020 03 14;13(1):19. Epub 2020 Mar 14.

Department of Thoracic Surgery, Xiangya Hospital, Central South University, Xiangya Road 87th, Changsha, 410008, Hunan, People's Republic of China.

Distinct from classical tumor angiogenesis, vasculogenic mimicry (VM) provides a blood supply for tumor cells independent of endothelial cells. VM has two distinct types, namely tubular type and patterned matrix type. VM is associated with high tumor grade, tumor progression, invasion, metastasis, and poor prognosis in patients with malignant tumors. Herein, we discuss the recent studies on the role of VM in tumor progression and the diverse mechanisms and signaling pathways that regulate VM in tumors. Furthermore, we also summarize the latest findings of non-coding RNAs, such as lncRNAs and miRNAs in VM formation. In addition, we review application of molecular imaging technologies in detection of VM in malignant tumors. Increasing evidence suggests that VM is significantly associated with poor overall survival in patients with malignant tumors and could be a potential therapeutic target.
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http://dx.doi.org/10.1186/s13045-020-00858-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7071697PMC
March 2020

Sequencing Mirror-Image DNA Chemically.

Cell Chem Biol 2018 09 12;25(9):1151-1156.e3. Epub 2018 Jul 12.

School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Center for Synthetic and Systems Biology, Ministry of Education Key Laboratory of Bioinformatics, Tsinghua University, Beijing 100084, China. Electronic address:

The development of mirror-image biology systems faces a crucial barrier of lacking an L-DNA sequencing technique. Here, we developed a practical method for sequencing mirror-image DNA by adopting the Maxam-Gilbert sequencing approach, through which specific nucleobases in an end-labeled L-DNA are cleaved by achiral chemicals. This technique may facilitate the therapeutic application of nuclease-resistant L-aptamer drugs, and bring the vision of building an alternative, mirror-image self-replicating system closer to reality.
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http://dx.doi.org/10.1016/j.chembiol.2018.06.005DOI Listing
September 2018

Mesoporous germanium nanoparticles synthesized in molten zinc chloride at low temperature as a high-performance anode for lithium-ion batteries.

Dalton Trans 2018 Jun;47(22):7402-7406

Hefei National Laboratory for Physical Science at Micro-scale, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China.

In a simple and convenient way, mesoporous germanium nanoparticles (mp-Ge NPs) are prepared by a "metathesis" reaction of magnesium germanide (Mg2Ge) and zinc chloride (ZnCl2) in an autoclave at 300 °C. Investigated as anode materials for lithium-ion batteries, the prepared mp-Ge NPs exhibit a high capacity retention of 1048 mA h g-1 at 1 C after 1000 cycles and a high rate capacity of 727.1 mA h g-1 at 10 C in Li-Ge half cells. Additionally, a 3.4 V lithium-ion full cell (Ge-LiCoO2) with an energy retention of 85% (∼268.8 W h kg-1) over 100 cycles is achieved.
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http://dx.doi.org/10.1039/c8dt01060aDOI Listing
June 2018

Flexible particle flow-focusing in microchannel driven by droplet-directed induced-charge electroosmosis.

Electrophoresis 2018 02 29;39(4):597-607. Epub 2017 Nov 29.

School of Mechatronics Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, P. R. China.

We report herein a novel microfluidic particle concentrator that utilizes constriction microchannels to enhance the flow-focusing performance of induced-charge electroosmosis (ICEO), where viscous hemi-spherical oil droplets are embedded within the mainchannel to form deformable converging-diverging constriction structures. The constriction region between symmetric oil droplets partially coated on the electrode strips can improve the focusing performance by inducing a granular wake flow area at the diverging channel, which makes almost all of the scattered sample particles trapped within a narrow stream on the floating electrode. Another asymmetric droplet pair arranged near the outlets can further direct the trajectory of focused particle stream to one specified outlet port depending on the symmetry breaking in the shape of opposing phase interfaces. By fully exploiting rectification properties of induced-charge electrokinetic phenomena at immiscible water/oil interfaces of tunable geometry, the expected function of continuous and switchable flow-focusing is demonstrated by preconcentrating both inorganic silica particles and biological yeast cells. Physical mechanisms responsible for particle focusing and locus deflection in the droplet-assisted concentrentor are analyzed in detail, and simulation results are in good accordance with experimental observations. Our work provides new routes to construct flexible electrokinetic framework for preprocessing on-chip biological samples before performing subsequent analysis.
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http://dx.doi.org/10.1002/elps.201700305DOI Listing
February 2018

Mirror-image polymerase chain reaction.

Cell Discov 2017 17;3:17037. Epub 2017 Oct 17.

School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Synthetic and Systems Biology, Ministry of Education Key Laboratory of Bioinformatics, Tsinghua University, Beijing, China.

The construction of mirror-image biological systems may open the next frontier for biomedical technology development and discovery. Here we have designed and chemically synthesized a mutant version of the thermostable P2 DNA polymerase IV (Dpo4) consisting of d-amino acids. With a total peptide length of 358 amino acid residues, it is the largest chemically synthesized d-amino acid protein reported to date. We show that the d-polymerase is able to amplify a 120-bp l-DNA sequence coding for the 5S ribosomal RNA gene by mirror-image polymerase chain reaction, and that both the natural and mirror-image systems operate with strict chiral specificity. The development of efficient miPCR systems may lead to many practical applications, such as mirror-image systematic evolution of ligands by exponential enrichment for the selection of therapeutically promising nuclease-resistant l-nucleic acid aptamers.
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http://dx.doi.org/10.1038/celldisc.2017.37DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5643884PMC
October 2017

Potential toxic trace element (PTE) contamination in Baoji urban soil (NW China): spatial distribution, mobility behavior, and health risk.

Environ Sci Pollut Res Int 2017 Aug 6;24(24):19749-19766. Epub 2017 Jul 6.

SNNU-JSU International Joint Research Centre for Nanoenvironment Science and Health, Shaanxi Normal University, Xi'an, 710062, Shaanxi, People's Republic of China.

Rapid urbanization and industrialization may cause increased exposure levels to potential toxic trace elements (PTEs) and associated health risks for population living in cities. The main objectives of this study are to investigate systematically the occurrence, source, fate, and risk of PTE contamination from industrial influence in Baoji urban soil. Seven PTE levels (Pb, Zn, Cu, Cr, V, Sb, and As) were surveyed in 50 composite samples from Baoji urban soil by wavelength dispersive X-ray fluorescence spectrometry. Results reveal that the long-term industrial activities have increased PTEs Pb (409.20 mg/kg mean value), Cu (107.19 mg/kg mean value), Zn (374.47 mg/kg mean value), and Sb (26.00 mg/kg mean value) to enrich in urban soil at the different extents. The same results concur with the significant similarity of spatial distribution patterns of Pb, Zn, Cu, and Sb (slightly similar distribution) interpolated by GIS, implying a considerable Pb, Zn, Cu, and Sb contamination pool in urban soil disturbance from local metallic industrial activities. Whereas As in study area mainly controls parent material leaching and therefore has natural sources. Cr and V with the heterogeneous spatial distributions are possibly inclined to coal combustion sources. Those conclusions are also confirmed by the results of multivariate analysis. The chemical forms of PTEs fractionated by BCR three-stage sequential extraction procedure show that Pb and Cu are highly associated to the reducible phase (62.55 and 36.41%, respectively). However, Zn is highly associated to the oxidizable phase (33.68%), and a significant concentration is associated to acid and water extractable fractionation of 15.93% for Zn and 34.40% for Pb. In contrast, As, Cr, V, and Sb are mainly bound to the residual phase (>65% for all elements) with low concentrations retained to water extractable fractionation. The health risk assessed by a new classification Modified Integrate Risk Assessment Code (MI-RAC) reveals that the Pb poses the extremely high risk for human health than others. The results of PTE leaching in organic acids (artificial chelating agent and LMMOAs) indicate that low pH and more carboxyl groups of organic acid can quickly increase the PTEs release from soil and induce more mobility. By comparison, DTPA and EDTA are the effective extractant for Pb and Sb. The leaching kinetics of most PTEs are best described with the Elovich equation model and which involve the ligand exchange (LE) and ligand-enhanced dissolution (LED) two major process. It is a conclusion that long-term metallic industrial activities would accelerate the PTE accumulations in Baoji urban soil and enhance their mobility in a local scale. The considerable mobility and extremely high risk of Pb in Baoji ecoenvironment should be paid more attentions, and the phytoremediation with organic acid leaching assistant could be used to reduce total metal content of multiPTE contaminants in Baoji soils. The research will give the scientific knowledge for controlling the pollution of PTEs in urban soil and can be used as guidance to control the soil pollution in similar cities worldwide.
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http://dx.doi.org/10.1007/s11356-017-9526-zDOI Listing
August 2017

Wet-Chemical Synthesis of Hollow Red-Phosphorus Nanospheres with Porous Shells as Anodes for High-Performance Lithium-Ion and Sodium-Ion Batteries.

Adv Mater 2017 Aug 26;29(29). Epub 2017 May 26.

Hefei National Laboratory for Physical Science at Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China.

Large-volume-expansion-induced material pulverization severely limits the electrochemical performance of red phosphorous (P) for energy-storage applications. Hollow nanospheres with porous shells are recognized as an ideal structure to resolve these issues. However, a chemical synthetic approach for preparing nanostructured red P is always of great challenge and hollow nanosphere structures of red P have not yet been fabricated. Herein, a wet solvothermal method to successfully fabricate hollow P nanospheres (HPNs) with porous shells via a gas-bubble-directed formation mechanism is developed. More importantly, due to the merits of the porous and hollow structures, these HPNs reveal the highest capacities (based on the weight of electrode materials) of 1285.7 mA h g for lithium-ion batteries and 1364.7 mA h g for sodium-ion batteries at 0.2 C, and excellent long-cycling performance.
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http://dx.doi.org/10.1002/adma.201700214DOI Listing
August 2017

Total chemical synthesis of a thermostable enzyme capable of polymerase chain reaction.

Cell Discov 2017 28;3:17008. Epub 2017 Feb 28.

School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Synthetic and Systems Biology, Ministry of Education Key Laboratory of Bioinformatics, Tsinghua University , Beijing, China.

Polymerase chain reaction (PCR) has been a defining tool in modern biology. Towards realizing mirror-image PCR, we have designed and chemically synthesized a mutant version of the 352-residue thermostable P2 DNA polymerase IV with l-amino acids and tested its PCR activity biochemically. To the best of our knowledge, this enzyme is the largest chemically synthesized protein reported to date. We show that with optimization of PCR conditions, the fully synthetic polymerase is capable of amplifying template sequences of up to 1.5 kb. The establishment of this synthetic route for chemically synthesizing DNA polymerase IV is a stepping stone towards building a d-enzyme system for mirror-image PCR, which may open up an avenue for the creation of many mirror-image molecular tools such as mirror-image systematic evolution of ligands by exponential enrichment.
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http://dx.doi.org/10.1038/celldisc.2017.8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5335361PMC
February 2017

B,N-Co-doped Graphene Supported Sulfur for Superior Stable Li-S Half Cell and Ge-S Full Battery.

ACS Appl Mater Interfaces 2016 Oct 11;8(41):27679-27687. Epub 2016 Oct 11.

Hefei National Laboratory for Physical Science at Microscale and Department of Chemistry, University of Science and Technology of China , Hefei, Anhui 230026, China.

B,N-Co-doped graphene supported sulfur ([email protected]) composite is synthesized by using melamine diborate as precursor. XPS spectra illustrates that BNG with a high percentage and dispersive B, N (B = 13.47%, N = 9.17%) and abundant pyridinic-N and N-B/N═B bond, show strong interaction with LiS proved by adsorption simulation experiments. As cathode for Li-S half cell, [email protected] with a sulfur content of 75% displays a reversible capacity of 765 mA h g at 1 C even after 500 cycles (a low fading rate of 0.027% per cycle). Even at a high sulfur loading of 4.73 mg cm, [email protected] still shows a high and stable areal capacity of 3.5 mA h cm after 48 cycles. When [email protected] composite as cathode combines with high performance lithiated Ge anode (discharge capacity of 1138 mA h g over 1000 cycles at 1 C in half cell), the assembled Ge-S full battery exhibits a superior capacity of 530 mA h g over 500 cycles at the rate of 1 C.
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http://dx.doi.org/10.1021/acsami.6b08852DOI Listing
October 2016

Solvothermal synthesis of a silicon hierarchical structure composed of 20 nm Si nanoparticles coated with carbon for high performance Li-ion battery anodes.

Dalton Trans 2016 Sep 3;45(35):13667-70. Epub 2016 Aug 3.

Hefei National Laboratory for Physical Science at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China.

A silicon hierarchical structure composed of 20 nm Si nanoparticles (Si-20) is synthesized using a solvothermal method. After coating with a carbon layer by pyrolysis of acetylene gas, the fabricated [email protected] composites exhibit a superior cycling performance with 915.8 mA h g(-1) at 3.6 A g(-1) over 500 cycles and a high rate performance with 746.2 mA h g(-1) at 10.8 A g(-1).
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http://dx.doi.org/10.1039/c6dt02551jDOI Listing
September 2016

Phosphorylation of glutamate receptors: a potential mechanism for the regulation of receptor function and psychostimulant action.

J Neurosci Res 2006 Dec;84(8):1621-9

Department of Basic Medical Science, University of Missouri-Kansas City, School of Medicine, Kansas City, MO, USA.

Ionotropic glutamate receptors, N-methyl-d-aspartate receptors (NMDARs) and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors (AMPARs), are densely distributed in the mammalian brain and actively regulate a variety of cellular activities. Expression and function of these receptors are also under a tight regulation by many molecular mechanisms. Protein phosphorylation represents one of the important mechanisms for the posttranslational modulation of these receptors. Constitutive and regulatory phosphorylation occurs at distinct sites (serine, threonine, or tyrosine) on the intracellular C-terminal domain of almost all subunits capable of assembling a functional channel. Several key protein kinases, such as protein kinase A, protein kinase C, Ca(2+)/calmodulin-dependent protein kinases, and tyrosine kinases are involved in the site-specific catalyzation and regulation of NMDAR and AMPAR phosphorylation. Through the phosphorylation mechanism, these protein kinases as well as protein phosphatases control biochemical properties (biosynthesis, delivery, and subunit assembling), subcellular distribution, and interactions of these receptors with various synaptic proteins, which ultimately modify the efficacy and strength of excitatory synapses containing NMDARs and AMPARs and many forms of synaptic plasticity. Emerging evidence shows that psychostimulants (cocaine and amphetamine) are among effective agents that profoundly alter the phosphorylation status of both receptors in striatal neurons in vivo. Thus, psychostimulants may modulate NMDAR and AMPAR function through the phosphorylation mechanism to shape the excitatory synaptic plasticity related to additive properties of drugs of abuse.
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http://dx.doi.org/10.1002/jnr.21050DOI Listing
December 2006

A signaling mechanism from G alpha q-protein-coupled metabotropic glutamate receptors to gene expression: role of the c-Jun N-terminal kinase pathway.

J Neurosci 2006 Jan;26(3):971-80

Department of Basic Medical Science, University of Missouri-Kansas City School of Medicine, Kansas City, Missouri 64108, USA.

Galphaq-protein-coupled group I metabotropic glutamate receptors (mGluRs) are densely expressed in brain neurons and are actively involved in various cellular activities. In this study, we investigated the role of group I mGluRs in regulating the c-Jun N-terminal kinase (JNK)/stress-activated protein kinase in cultured neurons. We found that selective activation of mGluR5 induced a rapid and transient phosphorylation of JNK. In a series of studies to determine the mechanisms, we found that the conventional mGluR5-associated signaling pathways (inositol-1,4,5-triphosphate-mediated Ca2+ release and activation of protein kinase C) were not involved in the mGluR5 regulation. Instead, ligand stimulation of mGluR5 caused a dynamic transactivation of the epidermal growth factor (EGF) receptor, which in turn triggered a downstream signaling pathway to upregulate JNK phosphorylation. Furthermore, the mGluR5-dependent JNK activation specifically activated c-Jun, but not activating transcription factor-2 or JunD, and increased activator protein-1 (AP-1)-mediated endogenous transcriptional activity. Together, we identified a novel mGluR5-to-nucleus communication through the EGF/JNK pathway, which functions to regulate AP-1-mediated transcription.
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http://dx.doi.org/10.1523/JNEUROSCI.4423-05.2006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6675367PMC
January 2006

Phosphorylation of AMPA receptors: mechanisms and synaptic plasticity.

Mol Neurobiol 2005 Dec;32(3):237-49

Department of Basic Medical Science, University of Missouri-Kansas City, School of Medicine, USA.

The ionotropic alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor is densely distributed in the mammalian brain and is primarily involved in mediating fast excitatory synaptic transmission. Recent studies in both heterologous expression systems and cultured neurons have shown that the AMPA receptor can be phosphorylated on their subunits (GluR1, GluR2, and GluR4). All phosphorylation sites reside at serine, threonine, or tyrosine on the intracellular C-terminal domain. Several key protein kinases, such as protein kinase A, protein kinase C, Ca2+/calmodulin-dependent protein kinase II, and tyrosine kinases (Trks; receptor or nonreceptor family Trks) are involved in the site-specific regulation of the AMPA receptor phosphorylation. Other glutamate receptors (N-methyl-d-aspartate receptors and metabotropic glutamate receptors) also regulate AMPA receptors through a protein phosphorylation mechanism. Emerging evidence shows that as a rapid and short-term mechanism, the dynamic protein phosphorylation directly modulates the electrophysiological, morphological (externalization and internalization trafficking and clustering), and biochemical (synthesis and subunit composition) properties of the AMPA receptor, as well as protein-protein interactions between the AMPA receptor subunits and various intracellular interacting proteins. These modulations underlie the major molecular mechanisms that ultimately affect many forms of synaptic plasticity.
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http://dx.doi.org/10.1385/MN:32:3:237DOI Listing
December 2005

Distinct efficacy of pre-differentiated versus intact fetal mesencephalon-derived human neural progenitor cells in alleviating rat model of Parkinson's disease.

Int J Dev Neurosci 2004 Jun;22(4):175-83

Neuroscience Research Institute, Peking University, 38# Xueyuan Road, Beijing 100083, PR China.

Neural progenitor cells have shown the effectiveness in the treatment of Parkinson's disease, but the therapeutic efficacy remains variable. One of important factors that determine the efficacy is the necessity of pre-differentiation of progenitor cells into dopaminergic neurons before transplantation. This study therefore investigated the therapeutic efficacy of mesencephalon-derived human neural progenitor cells with or without the pre-differentiation in alleviating a rat model of Parkinson's disease. We found that a combination of 50 ng/ml fibroblast growth factor 8, 10 ng/ml glial cell line-derived neurotrophic factor and 10 microM forskolin facilitated the differentiation of human fetal mesencephalic progenitor cells into dopaminergic neurons in vitro. More importantly, after transplanted into the striatum of parkinsonian rats, only pre-differentiated grafts resulted in an elevated production of dopamine in the transplanted site and the amelioration of behavioral impairments of the parkinsonian rats. Unlike pre-differentiated progenitors, grafted intact progenitors rarely differentiated into dopaminergic neurons in vivo and emigrated actively away from the transplanted site. These data demonstrates the importance of pre-differentiation of human progenitor cells before transplantation in enhancing therapeutic potency for Parkinson's disease.
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http://dx.doi.org/10.1016/j.ijdevneu.2004.05.008DOI Listing
June 2004
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