Publications by authors named "Xiaojun Wu"

386 Publications

Orbital Design of Two-Dimensional Transition-Metal Peroxide Kagome Crystals with Anionogenic Dirac Half-Metallicity.

J Phys Chem Lett 2021 Apr 2;12(14):3528-3534. Epub 2021 Apr 2.

Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Materials for Energy Conversion, CAS Center for Excellence in Nanoscience, and School of Chemistry and Materials Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China.

Assembling p orbital ferromagnetic half-metallicity and a topological element, such as a Dirac point at the Fermi level, in a single nanomaterial is of particular interest for long-distance, high-speed, and spin-coherent transportation in nanoscale spintronic devices. On the basis of the tight-binding model, we present an orbital design of a two-dimensional (2D) anionogenic Dirac half-metal (ADHM) by patterning cations with empty d orbitals and anions with partially filled p-type orbitals into a kagome lattice. Our first-principles calculations show that 2D transition-metal peroxides TM(O) (TMO, TM = Ti, Zr, Hf), containing group IVB transition-metal cations [TM] bridged with dioxygen anions [O] in a kagome structure, are stable ADHMs with a Curie temperature over 103 K. The 2/3 filled π* orbitals of dioxygen anions are ferromagnetically coupled, leading to p orbital ferromagnetism and a half-metallic Dirac point right at the Fermi level with a Fermi velocity reaching 2.84 × 10 m/s. We proposed that 2D TM(O) crystals may be extracted from ABO bulk materials containing 2D TMO layers.
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http://dx.doi.org/10.1021/acs.jpclett.1c00886DOI Listing
April 2021

Brain Neurotransmitter Modulation by Gut Microbiota in Anxiety and Depression.

Front Cell Dev Biol 2021 11;9:649103. Epub 2021 Mar 11.

Shanghai Key Laboratory of Compound Chinese Medicines, The Ministry of Education Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Center for Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China.

Anxiety and depression are highly prevalent mental illnesses worldwide and have long been thought to be closely associated to neurotransmitter modulation. There is growing evidence indicating that changes in the composition of the gut microbiota are related to mental health including anxiety and depression. In this review, we focus on combining the intestinal microbiota with serotonergic, dopaminergic, and noradrenergic neurotransmission in brain, with special emphasis on the anxiety- and depression-like behaviors in stress-related rodent models. Therefore, we reviewed studies conducted on germ-free rodents, or in animals subjected to microbiota absence using antibiotics, as well as via the usage of probiotics. All the results strongly support that the brain neurotransmitter modulation by gut microbiota is indispensable to the physiopathology of anxiety and depression. However, a lot of work is needed to determine how gut microbiota mediated neurotransmission in human brain has any physiological significance and, if any, how it can be used in therapy. Overall, the gut microbiota provides a novel way to alter neurotransmitter modulation in the brain and treat gut-brain axis diseases, such as anxiety and depression.
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http://dx.doi.org/10.3389/fcell.2021.649103DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7991717PMC
March 2021

Two-Dimensional CrXS (X = Br, I) Janus Semiconductor with Intrinsic Room-Temperature Magnetism.

J Phys Chem Lett 2021 Mar 16;12(11):2905-2911. Epub 2021 Mar 16.

Hefei National Laboratory for Physical Sciences at the Microscale, School of Chemistry and Materials Sciences, CAS Key Laboratory of Materials for Energy Conversion, and CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui 230026, China.

The exploration of two-dimensional (2D) semiconductors with intrinsic room-temperature magnetism for use in nanoscale spintronic devices is of particular interest. Recently, the ferromagnetic CrX monolayer (X = Br, I) has received growing attention, but low critical temperature hinders its practical applications in spintronics. Here, using first-principles calculations, we report 2D CrXS (X = Br, I) Janus semiconductors with room-temperature magnetism by replacing one layer of halogon atoms with sulfur atoms in CrX monolayer. Our results demonstrate that CrBrS and CrIS Janus crystals are ferrimagnetic semiconductors, that maintain their magnetic order, with a direct bandgap of 1.19 and 0.61 eV and high critical temperature of 387 and 447 K, respectively. The residual unpaired p electrons on the S anions lead to a strong direct-exchange interaction between the Cr and S atoms. Moreover, their room-temperature magnetism is robust under biaxial strain, while the bandgap can be remarkably modulated with strain. The novel magnetic properties in 2D CrXS Janus magnetic semiconductors give them promising applications in spintronics.
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http://dx.doi.org/10.1021/acs.jpclett.1c00454DOI Listing
March 2021

Chronic atrophic gastritis and intestinal metaplasia induced by high-salt and N-methyl-N'-nitro-N-nitrosoguanidine intake in rats.

Exp Ther Med 2021 Apr 3;21(4):315. Epub 2021 Feb 3.

Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200032, P.R. China.

The aim of the present study was to induce chronic atrophic gastritis (CAG) with intestinal metaplasia (IM) in rats by administering saturated salt and methyl-N'-nitro-N-nitrosoguanidine (MNNG) via oral gavage. Changes in gastric mucosal blood microcirculation and activation of the cyclo-oxygenase-2 (COX-2)/hypoxia inducible factor-1α (HIF-1α)/vascular endothelial growth factor (VEGF) signaling pathway during CAG and IM development were investigated. After administering saturated salt and MNNG for 25 weeks, mild atrophy was detected in the stomach of model rats using hematoxylin and eosin staining. CAG with IM was successfully induced in the gastric mucosa of the model rats after 35 weeks. Gastric mucosal blood flow was decreased in comparison with controls as early as 15 weeks after treatment to induce CAG and the mRNA expression levels of COX-2, HIF-1α, vascular endothelial growth factor receptor (VEGFR)1 and VEGFR2 were increased in comparison with untreated rats as early as 25 weeks after treatment. HIF-1α, COX-2 and VEGFR2 expression levels were increased as early as 25 weeks after CAG induction treatment when compared to controls and HIF-1α, COX-2, VEGFR1 and VEGFR2 expression levels were significantly increased after 35 weeks. These findings indicated that administering saturated salt and MNNG by gavage for 35 weeks successfully induced CAG and IM in rats. Furthermore, the microcirculation was disturbed before activation of the COX-2/HIF-1α/VEGF signaling pathway.
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http://dx.doi.org/10.3892/etm.2021.9746DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7885066PMC
April 2021

Stable Unbiased Photo-Electrochemical Overall Water Splitting Exceeding 3% Efficiency via Covalent Triazine Framework/Metal Oxide Hybrid Photoelectrodes.

Adv Mater 2021 Apr 9;33(15):e2008264. Epub 2021 Mar 9.

Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China.

Photo-electrochemical (PEC) water splitting systems using oxide-based photoelectrodes are highly attractive for solar-to-chemical energy conversion. However, despite decades-long efforts, it is still challenging to develop efficient and stable photoelectrodes for practical applications. Here, thin layers of covalent triazine frameworks (CTF-BTh) containing a bithiophene moiety are conformably deposited onto the surfaces of a Cu O photocathode and a Mo-doped BiVO photoanode via electropolymerization to construct new hybrid photoelectrodes, successfully addressing the efficiency and stability issues. The CTF-BTh possesses a suitable band structure to form favorable band edge alignment with each metal oxide, creating a p-n junction and a staggered type-II heterojunction with Cu O and Mo-doped BiVO , respectively. Thus, the as-fabricated hybrid photoelectrodes exhibit substantially increased PEC performances. Meanwhile, the CTF-BTh film also serves as an effective corrosion-resistant overlayer for both photoelectrodes to inhibit photocorrosion and enable long-term operation for 150 h with only ≈10% loss in photocurrent densities. Furthermore, a stand-alone unbiased PEC tandem device comprising CTF-BTh-coated photoelectrodes exhibits 3.70% solar-to-hydrogen conversion efficiency. Even after continuous operation for 120 h, the efficiency can still retain at 3.24%.
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http://dx.doi.org/10.1002/adma.202008264DOI Listing
April 2021

Mobile Plasmid Mediated Transition From Colistin-Sensitive to Resistant Phenotype in .

Front Microbiol 2021 15;12:619369. Epub 2021 Feb 15.

CAS Key Laboratory of Special Pathogens and Biosafety, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.

Multidrug-resistant bacteria, including carbapenem-resistant (CRKP), are becoming an increasing health crisis worldwide. For CRKP, colistin is regarded as "the last treatment option." In this study, we isolated a clinical CRKP strain named as R10-341. Phenotyping analysis showed that this strain could transit from a colistin-sensitive to a resistant phenotype by inserting an IS family IS element into the colistin-resistance associated gene. To investigate the mechanism of this transition, we performed genome sequencing analysis of the colistin-sensitive parental strain and found that 12 copies of IS containing direct repeats (DR) are located on the chromosome and 1 copy without DR is located on a multidrug-resistant plasmid pR10-341_2. Both types of IS could be inserted into the gene to cause colistin-resistance, though the plasmid-derived IS without DR was in higher efficiency. Importantly, we demonstrated that colistin-sensitive strain transferred with the IS element also obtained the ability to switch from colistin-sensitive to colistin-resistant phenotype. Furthermore, we confirmed that the IS-containing pR10-341_2 plasmid was able to conjugate, suggesting that the ability of causing colistin-resistant transition is transferable through common conjugation. Our results point to new challenges for both colistin-resistance detection and CRKP treatment.
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http://dx.doi.org/10.3389/fmicb.2021.619369DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7917065PMC
February 2021

Gegen Qinlian decoction relieved DSS-induced ulcerative colitis in mice by modulating Th17/Treg cell homeostasis via suppressing IL-6/JAK2/STAT3 signaling.

Phytomedicine 2021 Apr 18;84:153519. Epub 2021 Feb 18.

State Key Laboratory of Natural Medicines, Department of Biochemistry, China Pharmaceutical University, 24 Tongjia Xiang, Nanjing 210009, China. Electronic address:

Background: Gegen Qinlian decoction (GQ) is a traditional Chinese herbal prescription that has been widely used for the treatment of bacterial dysentery and enteric typhoid fever. Recently, GQ has been clinically reported to be a potential candidate for the treatment of ulcerative colitis (UC). However, the immunoregulatory function of GQ in the treatment of UC has not been fully elucidated.

Purpose: This study focused on the role of immune imbalance in the pathogenesis of UC and the immunomodulatory effect of GQ in the treatment of UC.

Methods: The UC model was established by treating female mice with 3.0% dextran sulfate sodium (DSS) for 7 days, and GQ was orally administered at dosages of 1.5 and 7.5 g/kg/day. Inflammatory factors were detected by ELISA and qRT-PCR. Treg and Th17 cell dysregulation was analyzed by qRT-PCR, immunohistochemistry and flow cytometry. Proteins related to IL-6/JAK2/STAT3 signaling were detected by western blotting.

Results: GQ significantly alleviated the symptoms of UC mice and suppressed the activity of myeloperoxidase (MPO). Furthermore, the production of proinflammatory factors, such as IL-1β, TNF-α and IL-6, was dramatically reduced after GQ administration. Furthermore, GQ improved the infiltration of Treg and Th17 cells into the colons and decreased the expression of inflammatory factors, such as TGF-β1 and IL-17. The frequencies of Treg and Th17 cells in the Peyer's patches and spleen were reduced by GQ administration; however, GQ had no significant regulatory effect on normal mice. The western blotting results showed that GQ markedly suppressed the phosphorylation of JAK2 and STAT3 and decreased the transcription function of phosphorylated STAT3.

Conclusions: Taken together, these results indicated that GQ alleviated DSS-induced UC by suppressing IL-6/JAK2/STAT3 signaling to restore Treg and Th17 cell homeostasis in colonic tissue.
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http://dx.doi.org/10.1016/j.phymed.2021.153519DOI Listing
April 2021

Evaluation of the safety and efficacy of using human menstrual blood-derived mesenchymal stromal cells in treating severe and critically ill COVID-19 patients: An exploratory clinical trial.

Clin Transl Med 2021 Feb;11(2):e297

State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, P. R. China.

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified in December 2019 and has subsequently spread worldwide. Currently, there is no effective method to cure COVID-19. Mesenchymal stromal cells (MSCs) may be able to effectively treat COVID-19, especially for severe and critical patients. Menstrual blood-derived MSCs have recently received much attention due to their superior proliferation ability and their lack of ethical problems. Forty-four patients were enrolled from January to April 2020 in a multicenter, open-label, nonrandomized, parallel-controlled exploratory trial. Twenty-six patients received allogeneic, menstrual blood-derived MSC therapy, and concomitant medications (experimental group), and 18 patients received only concomitant medications (control group). The experimental group was treated with three infusions totaling 9 × 10 MSCs, one infusion every other day. Primary and secondary endpoints related to safety and efficacy were assessed at various time points during the 1-month period following MSC infusion. Safety was measured using the frequency of treatment-related adverse events (AEs). Patients in the MSC group showed significantly lower mortality (7.69% died in the experimental group vs 33.33% in the control group; P = .048). There was a significant improvement in dyspnea while undergoing MSC infusion on days 1, 3, and 5. Additionally, SpO was significantly improved following MSC infusion, and chest imaging results were improved in the experimental group in the first month after MSC infusion. The incidence of most AEs did not differ between the groups. MSC-based therapy may serve as a promising alternative method for treating severe and critical COVID-19.
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http://dx.doi.org/10.1002/ctm2.297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7839959PMC
February 2021

Identification of candidate repurposable drugs to combat COVID-19 using a signature-based approach.

Sci Rep 2021 02 24;11(1):4495. Epub 2021 Feb 24.

Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Health Science Campus, Mail Stop #1007, 3000 Arlington Avenue, Toledo, OH, 43614-2598, USA.

The COVID-19 pandemic caused by the novel SARS-CoV-2 is more contagious than other coronaviruses and has higher rates of mortality than influenza. Identification of effective therapeutics is a crucial tool to treat those infected with SARS-CoV-2 and limit the spread of this novel disease globally. We deployed a bioinformatics workflow to identify candidate drugs for the treatment of COVID-19. Using an "omics" repository, the Library of Integrated Network-Based Cellular Signatures (LINCS), we simultaneously probed transcriptomic signatures of putative COVID-19 drugs and publicly available SARS-CoV-2 infected cell lines to identify novel therapeutics. We identified a shortlist of 20 candidate drugs: 8 are already under trial for the treatment of COVID-19, the remaining 12 have antiviral properties and 6 have antiviral efficacy against coronaviruses specifically, in vitro. All candidate drugs are either FDA approved or are under investigation. Our candidate drug findings are discordant with (i.e., reverse) SARS-CoV-2 transcriptome signatures generated in vitro, and a subset are also identified in transcriptome signatures generated from COVID-19 patient samples, like the MEK inhibitor selumetinib. Overall, our findings provide additional support for drugs that are already being explored as therapeutic agents for the treatment of COVID-19 and identify promising novel targets that are worthy of further investigation.
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http://dx.doi.org/10.1038/s41598-021-84044-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7904823PMC
February 2021

Metal Cyclopropenylidene Sandwich Cluster and Nanowire: Structural, Electronic, and Magnetic Properties.

J Phys Condens Matter 2021 Feb 22. Epub 2021 Feb 22.

University of Science and Technology of China, Jinzhai Road 96, Hefei, Anhui, 230026, CHINA.

Organometallic sandwich clusters and nanowires can offer prototypes for molecular ferromagnet and nanoscale spintronic devices due to the strong coupling of local magnetic moments in the nanowires direction and experimental feasibility. Here, on the basis of first-principles calculations, we report TMn(c-C3H2)n+1 (TM = Ti, Mn; n = 1-4) sandwich clusters and 1D [TM(c-C3H2)]∞ sandwich nanowires building from transitional metal and the smallest aromatic carbene of cyclopropenylidene (c-C3H2). Based on the results of lattice dynamic and thermodynamic studies, we show that the magnetic moment of Mnn(c-C3H2)n+1 clusters increases linearly with the number of n, and 1D [Mn(c-C3H2)]∞ nanowire is a stable ferromagnetic semiconductor, which can be converted into half metal with carrier doping. In contrary, both Tin(c-C3H2)n+1 and 1D [Ti(c-C3H2)]∞ nanowire are nonmagnetic materials. This study reveals the potential application of the [TM(c-C3H2)]∞ nanowire in spintronics.
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http://dx.doi.org/10.1088/1361-648X/abe8a0DOI Listing
February 2021

RSPO4-CRISPR alleviates liver injury and restores gut microbiota in a rat model of liver fibrosis.

Commun Biol 2021 Feb 18;4(1):230. Epub 2021 Feb 18.

Intensive Care Unit, The Second Affiliated Hospital of Zhejiang University, Hangzhou, Zhejiang Province, PR China.

Wnt signaling dysfunction and gut dysbiosis may lead to liver fibrosis, yet the underlying mechanisms are not well elucidated. This study demonstrated the role of RSPO4, a Wnt signaling agonist, in liver fibrogenesis and its impact on the gut microbiome. RSPO4 gene in CCl-induced fibrotic-liver rats was knockout by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) system, with healthy rats served as the control. Tissue samples and hepatic stellate cells (HSCs) isolated from rats were examined for curative effect of RSPO4-CRISPR treatment. Fecal sample were collected and analyzed with 16 S rRNA sequencing. We found RSPO4-CRISPR relieved liver fibrosis in rats and reversed HSC activation. Further, results showed RSPO4-CRISPR tended to restore the microflora composition. Significance species between groups were identified. Bacteroides and Escherichia-Shigella were the key microbes in the model and negative group, whereas Lactobacillus, Romboutsia, and Lachnospiraceae NK4A136 group were abundant in the control. Notably, Bacteroidales S24-7 group and Ruminococcaceae UCG-005 were the significantly enriched in CRISPR group. We show that the microbiome of rats treated with RSPO4-CRISPR presents a trend towards the restoration of the original condition. Our findings pave a new way to evaluate the curative effect of liver fibrosis treatment.
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http://dx.doi.org/10.1038/s42003-021-01747-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7893072PMC
February 2021

Hydrogen Oxidation Pathway Over Ni-Ceria Electrode: Combined Study of DFT and Experiment.

Front Chem 2020 1;8:591322. Epub 2021 Feb 1.

Chinese Academy of Sciences (CAS) Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, China.

Ni-ceria cermets are potential anodes for intermediate-temperature solid oxide fuel cells, thanks to the catalytic activity and mixed conductivities of ceria-based materials associated with the variable valence states of cerium. However, the anodic reaction mechanism in the Ni-ceria systems needs to be further revealed. Via density functional theory with strong correlated correction method, this work gains insight into reaction pathways of hydrogen oxidation on a model system of Ni-CeO(111). The calculation shows that electrons tend to be transferred from Ni cluster to cerium surface, creating surface oxygen vacancies. Six pathways are proposed considering different adsorption sites, and the interface pathway proceeding with hydrogen spillover is found to be the prevailing process, which includes a high adsorption energy of -1.859 eV and an energy barrier of 0.885 eV. The density functional theory (DFT) calculation results are verified through experimental measurements including electrical conductivity relaxation and temperature programmed desorption. The contribution of interface reaction to the total hydrogen oxidation reaction reaches up to 98%, and the formation of Ni-ceria interface by infiltrating Ni to porous ceria improves the electrochemical activity by 72% at 800°C.
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http://dx.doi.org/10.3389/fchem.2020.591322DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7882610PMC
February 2021

Topology Selectivity in On-Surface Dehydrogenative Coupling Reaction: Dendritic Structure Porous Graphene Nanoribbon.

ACS Nano 2021 Mar 16;15(3):4617-4626. Epub 2021 Feb 16.

National Synchrotron Radiation Laboratory, Department of Chemical Physics and Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei 230029, P.R. China.

Selective control on the topology of low-dimensional covalent organic nanostructures in on-surface synthesis has been challenging. Herein, with combined scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS), we report a successful topology-selective coupling reaction on the Cu(111) surface by tuning the thermal annealing procedure. The precursor employed is 1,3,5-tris(2-bromophenyl)benzene (TBPB), for which Ullmann coupling is impeded due to the intermolecular steric hindrance. Instead, its chemisorption on the Cu(111) substrate has triggered the C-H bond activation and the following dehydrogenative coupling at room temperature (RT). In the slow annealing experimental procedure, the monomers have been preorganized by their self-assembly at RT, which enhances the formation of dendritic structures upon further annealing. However, the chaotic chirality of dimeric products (obtained at RT) and hindrance from dense molecular island make the fabrication of high-quality porous two-dimensional nanostructures difficult. In sharp contrast, direct deposition of TBPB molecules on a hot surface led to the formation of ordered porous graphene nanoribbons and nanoflakes, which is confirmed to be the energetically favorable reaction pathway through density functional theory-based thermodynamic calculations and control experiments. This work demonstrates that different thermal treatments could have a significant influence on the topology of covalent products in on-surface synthesis and presents an example of the negative effect of molecular self-assembly to the ordered covalent nanostructures.
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http://dx.doi.org/10.1021/acsnano.0c08920DOI Listing
March 2021

MicroRNA-155 Controls NKT Cell Development and Lineage Differentiation by Coordinating Multiple Regulating Pathways.

Front Cell Dev Biol 2020 12;8:619220. Epub 2021 Jan 12.

Center for Cutaneous Biology and Immunology Research, Department of Dermatology, Henry Ford Health System, Detroit, MI, United States.

The development of invariant natural killer T (NKT) cells requires a well-attuned set of transcription factors, but how these factors are regulated and coordinated remains poorly understood. MicroRNA-155 (miR-155) is a key regulator of numerous cellular processes that affects cell development and homeostasis. Here, we found that miR-155 was highly expressed in early NKT cells upon thymic selection, and then its expression is gradually downregulated during NKT cell development. However, the mice with miR-155 germline deletion had normal NKT cell development. To address if downregulated miR-155 is required for NKT cell development, we made a CD4Cre.miR-155 knock-in (KI) mouse model with miR-155 conditional overexpression in the T cell lineage. Upregulated miR-155 led to interruption of NKT cell development, diminished NKT17 and NKT1 cells, augmented NKT2 cells, and these defects were cell intrinsic. Furthermore, defective NKT cells in miR-155KI mice resulted in the secondary innate-like CD8 T cell development. Mechanistically, miR-155 modulated multiple targets and signaling pathways to fine tune NKT cell development. MiR-155 modulated , a critical component of a histone modification complex, and , the upstream activation kinase complex component of NF-κB, which function additively in NKT development and in promoting balanced NKT1/NKT2 differentiation. In addition, miR-155 also targeted , a signature component of mTORC2 that controls NKT17 differentiation. Taken together, our results indicate that miR-155 serves as a key epigenetic regulator, coordinating multiple signaling pathways and transcriptional programs to precisely regulate NKT cell development and functional lineage, as well as secondary innate CD8 T cell development.
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http://dx.doi.org/10.3389/fcell.2020.619220DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7874147PMC
January 2021

Helichrysetin and TNF‑α synergistically promote apoptosis by inhibiting overactivation of the NF‑κB and EGFR signaling pathways in HeLa and T98G cells.

Int J Mol Med 2021 Apr 12;47(4). Epub 2021 Feb 12.

Shanghai Key Laboratory of Compound Chinese Medicines, The Ministry of Education Key Laboratory for Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P.R. China.

Tumor necrosis factor‑α (TNF‑α) has different effects on apoptosis depending on activation or inactivation of the nuclear factor‑κB (NF‑κB) and epidermal growth factor receptor (EGFR) signaling pathways. Helichrysetin, a natural chalcone, inhibits NF‑κB nuclear translocation in mouse pancreatic β cells. The present study aimed to identify the effect of helichrysetin on activation of the NF‑κB and EGFR signaling pathways induced by TNF‑α, and the synergistic effect of helichrysetin and TNF‑α on apoptosis of HeLa and T98G cells. Cell proliferation was measured by Cell Counting Kit‑8 assay, while apoptosis was measured by Hoechst 33258 and Annexin V/PI staining. NF‑κB activity was detected by luciferase assay, protein expression was measured by western blotting and mRNA expression was detected by quantitative PCR assay. The results revealed that in HeLa and T98G cells helichrysetin blocked the increased phosphorylation of NF‑κB p65 induced by TNF‑α. Although helichrysetin alone decreased cell viability, helichrysetin and TNF‑α synergistically decreased cell viability. Helichrysetin, not TNF‑α, promoted apoptosis, while the combination of helichrysetin and TNF‑α synergistically increased apoptosis. In addition, helichrysetin and TNF‑α synergistically enhanced the activation of caspase‑3 and poly‑(ADP‑ribose)‑polymerase compared with helichrysetin alone. Helichrysetin inhibited the phosphorylation of transforming growth factor‑β activated kinase (TAK1), IκB kinase‑α/β (IKK‑α/β), NF‑κB p65 and EGFR induced by TNF‑α. Consistent with the inhibition of NF‑κB activation, the increased TNF‑α‑induced mRNA expression levels of TNF‑α, IL‑1β, CCL2, CCL5 and CXCL10 were significantly downregulated by helichrysetin. Therefore, helichrysetin and TNF‑α synergistically promoted apoptosis by inhibiting TAK1/IKK/NF‑κB and TAK1/EGFR signaling pathways in HeLa and T98G cells, indicating a potential therapeutic strategy for cancer.
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http://dx.doi.org/10.3892/ijmm.2021.4882DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7891838PMC
April 2021

Efficient Photoelectrochemical Conversion of Methane into Ethylene Glycol by WO Nanobar Arrays.

Angew Chem Int Ed Engl 2021 Apr 17;60(17):9357-9361. Epub 2021 Mar 17.

Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), School of Chemistry and Materials Science, National Synchrotron Radiation Laboratory, and CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui, 230026, China.

Photoelectrochemical (PEC) conversion of methane (CH ) has been extensively explored for the production of value-added chemicals, yet remains a great challenge in high selectivity toward C products. Herein, we report the optimization of the reactivity of hydroxyl radicals ( OH) on WO via facet tuning to achieve efficient ethylene glycol production from PEC CH conversion. A combination of materials simulation and radicals trapping test provides insight into the reactivity of OH on different facets of WO , showing the highest reactivity of surface-bound OH on {010} facets. As such, the WO with the highest {010} facet ratio exhibits a superior PEC CH conversion efficiency, reaching an ethylene glycol production rate of 0.47 μmol cm  h . Based on in situ characterization, the methanol, which could be attacked by reactive OH to form hydroxymethyl radicals, is confirmed to be the main intermediate for the production of ethylene glycol. Our finding is expected to provide new insight for the design of active and selective catalysts toward PEC CH conversion.
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http://dx.doi.org/10.1002/anie.202101701DOI Listing
April 2021

Myelodysplastic syndrome with t(6;9)(p22;q34.1)/DEK-NUP214 better classified as acute myeloid leukemia? A multicenter study of 107 cases.

Mod Pathol 2021 Feb 8. Epub 2021 Feb 8.

Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.

t(6;9)(p22;q34.1)/DEK-NUP214 is a recurrent genetic abnormality that occurs in 1-2% of patients with acute myeloid leukemia (AML), and rarely in myelodysplastic syndrome (MDS). It has been suggested by others that all myeloid neoplasms with t(6;9)/DEK-NUP214 may be considered as AML, even when blast count is <20%. In this study, we compared the clinicopathologic features of 107 patients with myeloid neoplasms harboring t(6;9)/DEK-NUP214: 33 MDS and 74 AML. Compared with patients with AML, patients with MDS were older (p = 0.10), had a lower white blood cell count (p = 0.0017), a lower blast count in the peripheral blood (p < 0.0001) and bone marrow (p < 0.0001), a higher platelet count (p = 0.022), and a lower frequency of FLT3-ITD mutation (p = 0.01). In addition, basophilia was not a common feature in the patients of this cohort. Although there was no difference in overall survival between MDS and AML patients (p = 0.18) in the entire cohort, the survival curves did show a trend toward favorable survival in MDS patients. Multivariate analyses showed that initial diagnosis of MDS vs. AML and allogeneic hematopoietic stem cell transplantation were prognostic factors for survival of patients with t(6;9)/DEK-NUP214 (p = 0.008 and p < 0.0001, respectively). Our data suggest that MDS with t(6;9)/DEK-NUP214 is prognostically not equivalent to AML with t(6;9)/DEK-NUP214. These data also show that stem cell transplantation greatly improves the survival of MDS and AML patients with myeloid neoplasms associated with t(6;9)/DEK-NUP214.
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http://dx.doi.org/10.1038/s41379-021-00741-wDOI Listing
February 2021

DDB2 regulates DNA replication through PCNA-independent degradation of CDT2.

Cell Biosci 2021 Feb 8;11(1):34. Epub 2021 Feb 8.

State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, 518055, Shenzhen, China.

Background: Targeting ubiquitin-dependent proteolysis is one of the strategies in cancer therapy. CRL and CRL are two key E3 ubiquitin ligases involved in DNA replication and DNA damage repair. But CDT2 and DDB2 are opposite prognostic factors in kinds of cancers, and the underlining mechanism needs to be elucidated.

Methods: Small interfering RNAs were used to determine the function of target genes. Co-immunoprecipitation (Co-IP) was performed to detect the interaction between DDB2 and CDT2. Immunofluorescence assays and fluorescence activating cell sorting (FACS) were used to measure the change of DNA content. In vivo ubiquitination assay was carried out to clarify the ubiquitination of CDT2 mediated by DDB2. Cell synchronization was performed to arrest cells at G1/S and S phase. The mechanism involved in DDB2-mediated CDT2 degradation was investigated by constructing plasmids with mutant variants and measured by Western blot. Immunohistochemistry was performed to determine the relationship between DDB2 and CDT2. Paired two-side Student's t-test was used to measure the significance of the difference between control group and experimental group.

Results: Knockdown of DDB2 stabilized CDT2, while over-expression of DDB2 enhanced ubiquitination of CDT2, and subsequentially degradation of CDT2. Although both DDB2 and CDT2 contain PIP (PCNA-interacting protein) box, PIP box is dispensable for DDB2-mediated CDT2 degradation. Knockdown of PCNA had negligible effects on the stability of CDT2, but promoted accumulation of CDT1, p21 and SET8. Silencing of DDB2 arrested cell cycle in G1 phase, destabilized CDT1 and reduced the chromatin loading of MCMs, thereby blocked the formation of polyploidy induced by ablation of CDT2. In breast cancer and ovarian teratoma tissues, high level of DDB2 was along with lower level of CDT2.

Conclusions: We found that CRL4 is the novel E3 ubiquitin ligases of CDT2, and DDB2 regulates DNA replication through indirectly regulates CDT1 protein stability by degrading CDT2 and promotes the assembly of pre-replication complex. Our results broaden the horizon for understanding the opposite function of CDT2 and DDB2 in tumorigenesis, and may provide clues for drug discovery in cancer therapy.
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http://dx.doi.org/10.1186/s13578-021-00540-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7869461PMC
February 2021

Similarities and dissimilarities between psychiatric cluster disorders.

Mol Psychiatry 2021 Jan 27. Epub 2021 Jan 27.

Department of Neurosciences, University of Toledo College of Medicine and Life Sciences, Toledo, OH, USA.

The common molecular mechanisms underlying psychiatric disorders are not well understood. Prior attempts to assess the pathological mechanisms responsible for psychiatric disorders have been limited by biased selection of comparable disorders, datasets/cohort availability, and challenges with data normalization. Here, using DisGeNET, a gene-disease associations database, we sought to expand such investigations in terms of number and types of diseases. In a top-down manner, we analyzed an unbiased cluster of 36 psychiatric disorders and comorbid conditions at biological pathway, cell-type, drug-target, and chromosome levels and deployed density index, a novel metric to quantify similarities (close to 1) and dissimilarities (close to 0) between these disorders at each level. At pathway level, we show that cognition and neurotransmission drive the similarity and are involved across all disorders, whereas immune-system and signal-response coupling (cell surface receptors, signal transduction, gene expression, and metabolic process) drives the dissimilarity and are involved with specific disorders. The analysis at the drug-target level supports the involvement of neurotransmission-related changes across these disorders. At cell-type level, dendrite-targeting interneurons, across all layers, are most involved. Finally, by matching the clustering pattern at each level of analysis, we showed that the similarity between the disorders is influenced most at the chromosomal level and to some extent at the cellular level. Together, these findings provide first insights into distinct cellular and molecular pathologies, druggable mechanisms associated with several psychiatric disorders and comorbid conditions and demonstrate that similarities between these disorders originate at the chromosome level and disperse in a bottom-up manner at cellular and pathway levels.
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http://dx.doi.org/10.1038/s41380-021-01030-3DOI Listing
January 2021

Mechanical Properties of Atomically Thin Tungsten Dichalcogenides: WS, WSe, and WTe.

ACS Nano 2021 Feb 27;15(2):2600-2610. Epub 2021 Jan 27.

Institute for Frontier Materials, Deakin University, Geelong Waurn Ponds Campus, Waurn Ponds, Geelong, Victoria 3216, Australia.

Two-dimensional (2D) tungsten disulfide (WS), tungsten diselenide (WSe), and tungsten ditelluride (WTe) draw increasing attention due to their attractive properties deriving from the heavy tungsten and chalcogenide atoms, but their mechanical properties are still mostly unknown. Here, we determine the intrinsic and air-aged mechanical properties of mono-, bi-, and trilayer (1-3L) WS, WSe, and WTe using a complementary suite of experiments and theoretical calculations. High-quality 1L WS has the highest Young's modulus (302.4 ± 24.1 GPa) and strength (47.0 ± 8.6 GPa) of the entire family, overpassing those of 1L WSe (258.6 ± 38.3 and 38.0 ± 6.0 GPa, respectively) and WTe (149.1 ± 9.4 and 6.4 ± 3.3 GPa, respectively). However, the elasticity and strength of WS decrease most dramatically with increased thickness among the three materials. We interpret the phenomenon by the different tendencies for interlayer sliding in an equilibrium state and under in-plane strain and out-of-plane compression conditions in the indentation process, revealed by the finite element method and density functional theory calculations including van der Waals interactions. We also demonstrate that the mechanical properties of the high-quality 1-3L WS and WSe are largely stable in air for up to 20 weeks. Intriguingly, the 1-3L WSe shows increased modulus and strength values with aging in the air. This is ascribed to oxygen doping, which reinforces the structure. The present study will facilitate the design and use of 2D tungsten dichalcogenides in applications such as strain engineering and flexible field-effect transistors.
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http://dx.doi.org/10.1021/acsnano.0c07430DOI Listing
February 2021

Ultra-low-loss on-chip zero-index materials.

Light Sci Appl 2021 Jan 7;10(1):10. Epub 2021 Jan 7.

State Key Laboratory of Precision Measurement Technology and Instrument, Department of Precision Instrument, Tsinghua University, 100084, Beijing, China.

Light travels in a zero-index medium without accumulating a spatial phase, resulting in perfect spatial coherence. Such coherence brings several potential applications, including arbitrarily shaped waveguides, phase-mismatch-free nonlinear propagation, large-area single-mode lasers, and extended superradiance. A promising platform to achieve these applications is an integrated Dirac-cone material that features an impedance-matched zero index. Although an integrated Dirac-cone material eliminates ohmic losses via its purely dielectric structure, it still entails out-of-plane radiation loss, limiting its applications to a small scale. We design an ultra-low-loss integrated Dirac cone material by achieving destructive interference above and below the material. The material consists of a square array of low-aspect-ratio silicon pillars embedded in silicon dioxide, featuring easy fabrication using a standard planar process. This design paves the way for leveraging the perfect spatial coherence of large-area zero-index materials in linear, nonlinear, and quantum optics.
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http://dx.doi.org/10.1038/s41377-020-00436-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7791033PMC
January 2021

Pd-Modified ZnO-Au Enabling Alkoxy Intermediates Formation and Dehydrogenation for Photocatalytic Conversion of Methane to Ethylene.

J Am Chem Soc 2021 Jan 29;143(1):269-278. Epub 2020 Dec 29.

Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), School of Chemistry and Materials Science, and National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China.

Photocatalysis provides an intriguing approach for the conversion of methane to multicarbon (C) compounds under mild conditions; however, with methyl radicals as the sole reaction intermediate, the current C products are dominated by ethane, with a negligible selectivity toward ethylene, which, as a key chemical feedstock, possesses higher added value than ethane. Herein, we report a direct photocatalytic methane-to-ethylene conversion pathway involving the formation and dehydrogenation of alkoxy (i.e., methoxy and ethoxy) intermediates over a Pd-modified ZnO-Au hybrid catalyst. On the basis of various characterizations, it is revealed that the Pd-induced dehydrogenation capability of the catalyst holds the key to turning on the pathway. During the reaction, methane molecules are first dissociated into methoxy on the surface of ZnO under the assistance of Pd. Then these methoxy intermediates are further dehydrogenated and coupled with methyl radical into ethoxy, which can be subsequently converted into ethylene through dehydrogenation. As a result, the optimized ZnO-AuPd hybrid with atomically dispersed Pd sites in the Au lattice achieves a methane conversion of 536.0 μmol g with a C compound selectivity of 96.0% (39.7% CH and 54.9% CH in total produced C compounds) after 8 h of light irradiation. This work provides fresh insight into the methane conversion pathway under mild conditions and highlights the significance of dehydrogenation for enhanced photocatalytic activity and unsaturated hydrocarbon product selectivity.
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http://dx.doi.org/10.1021/jacs.0c10369DOI Listing
January 2021

Characterization and Optimization of Elastomeric Electrodes for Dielectric Elastomer Artificial Muscles.

Materials (Basel) 2020 Dec 4;13(23). Epub 2020 Dec 4.

School of Mechanical and Electronic Engineering, Wuhan University of Technology, Wuhan 430070, China.

Dielectric elastomer actuators (DEAs) are an emerging type of soft actuation technology. As a fundamental unit of a DEA, the characteristics of compliant electrodes play a crucial role in the actuation performances of DEAs. Generally, the compliant electrodes can be categorized into uncured and cured types, of which the cured one commonly involves mixing conductive particles into an elastomeric matrix before curing, thus demonstrating a better long-term performance. Along with the increasing proportion of conductive particles, the electrical conductivity increases at the cost of a stiffer electrode and lower elongation at break ratio. For different DEA applications, it can be more desirable to minimize the electrode stiffness or to maximize its conductivity. In examination of the papers published in recent years, few works have characterized the effects of elastomeric electrodes on the outputs of DEAs, or of their optimizations under different application scenarios. In this work, we propose an experimental framework to characterize the performances of elastomeric electrodes with different formulas based on the two key parameters of stiffness and conductivity. An optimizing method is developed and verified by two different application cases (e.g., quasi-static and dynamic). The findings and the methods developed in this work can offer potential approaches for developing high-performance DEAs.
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http://dx.doi.org/10.3390/ma13235542DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7729933PMC
December 2020

Round ligament suspending treatment in orthotopic ileal-neobladder after radical cystectomy in women: a single-centre prospective randomised trial.

BJU Int 2020 Nov 28. Epub 2020 Nov 28.

Department of Urology, Urology Institute of PLA, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.

Objectives: To compare the occurrence of emptying dysfunction between surgical techniques for orthotopic neobladder suspended with round ligament (rONB) and the standard procedure (sONB).

Patients And Methods: A prospective randomised controlled trial was performed in a single centre of female patients undergoing creation of an ONB using rONB or sONB. Patients were followed for ≥24 months after ONB. The primary endpoints were significant post-void residual urine volume (sPVR) and need for clean intermittent catheterisation (CIC) at 24 months postoperatively. The secondary endpoints included early and late complications, urodynamic profile, and ONB continence.

Results: Between January 2011 and October 2017, the trial enrolled 85 patients, of whom 82 were randomised. A total of 41 patients had a rONB and 41 a sONB. At 24 months, 17 of the 37 patients with a sONB and nine of the 39 patients with a rONB had a sPVR. The cumulative risk of a sPVR was significantly lower in the rONB group (23.1%) vs the sONB group (45.9%) (hazard ratio [HR] 0.43, 95% confidence interval [CI], 0.19-0.96; P = 0.040). In all, 15 of the 37 patients with a sONB and four of the 39 patients with a rONB needed CIC. The cumulative risk of requiring CIC was significantly lower in the rONB group (10.3%) vs the sONB group (40.5%) (HR 0.22, 95% CI 0.07-0.67; P = 0.008) at 24 months. Multivariable Cox regression analysis also showed that the rONB type was an independently protective factor for sPVR and CIC. The rates of early (0-90 days) and late complication (>90 days) were 54.1% and 13.5% in the sONB group, and 64.1% and 10.3% in the rONB group, respectively. There were no significant differences in complications, urodynamic profile or ONB continence. A major limitation is the small sample size at a single centre.

Conclusion: Posterior support with round ligament for an ONB significantly improved the emptying of the ONB and resulted in a reduced need for CIC. The surgical modification is a feasible and safe technique without additional complication-related surgeries.
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http://dx.doi.org/10.1111/bju.15306DOI Listing
November 2020

A combination of three plasma bile acids as a putative biomarker for schizophrenia.

Acta Neuropsychiatr 2021 Feb 23;33(1):51-54. Epub 2020 Nov 23.

Shanghai Key Laboratory of Compound Chinese Medicines, The Ministry of Education (MOE) Key Laboratory for Standardization of Chinese Medicines, Shanghai R&D Center for Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, People's Republic of China.

The aim of the present study is to determine whether plasma bile acids (BAs) could be used as an auxiliary diagnostic biomarker to distinguish patients with schizophrenia from healthy controls. Seventeen different BAs were quantitatively measured in plasma of 12 healthy participants and 12 patients with schizophrenia. Then, the data were subjected to correlation and linear discriminant analysis (LDA). The concentrations of cholic acid (CA), taurochenodeoxycholic acid (TCDCA) and taurodeoxycholic acid (TDCA) were significantly decreased in plasma of the schizophrenia patients. Correlation analysis showed the concentrations of CA, TCDCA and TDCA were negatively correlated with schizophrenia. In addition, LDA demonstrated that combination of CA, TCDCA and TDCA with a classification formula could predict correctly classified cases and the accuracy of prediction was up to 95.83%. Combination of the three BAs may be useful to diagnose schizophrenia in plasma samples.
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http://dx.doi.org/10.1017/neu.2020.42DOI Listing
February 2021

Generation of tailored terahertz waves from monolithic integrated metamaterials onto spintronic terahertz emitters.

Nanotechnology 2021 Mar;32(10):105201

School of Microelectronics, Beihang University, Beijing, 100191, People's Republic of China. Beihang-Goertek Joint Microelectronics Institute, Qingdao Research Institute, Beihang University, Qingdao, 266000, People's Republic of China. Hefei Innovation Research Institute, Beihang University, Hefei 230013, People's Republic of China.

Recently emerging spintronic terahertz (THz) emitters, featuring many appreciable merits such as low-cost, high efficiency, ultrabroadband, and ease of integration, offer multifaceted capabilities not only in understanding the fundamental ultrafast magnetism physics but also for exploring multifarious practical applications. Integration of various flexible and tunable functions at the source such as polarization manipulation, amplitude tailoring, phase modulation, and radiation beam steering with the spintronic THz emitters and their derivatives can yield more compact and elegant devices. Here, we demonstrate a monolithic metamaterial integrated onto a W/CoFeB/Pt THz nanoemitter for a purpose-designed functionality of the electromagnetically induced transparency analog. Through elaborate engineering the asymmetry degree and geometric parameters of the metamaterial structure, we successfully verified the feasibility of monolithic modulations for the radiated THz waves. The integrated device was eventually compared with a set of stand-alone metamaterial positioning scenarios, and the negligible frequency difference between two of the positioning schemes further manifests almost an ideal realization of the proposed monolithic integrated metamaterial device with a spintronic THz emitter. We believe that such adaptable and scalable devices may make valuable contributions to the designable spintronic THz devices with pre-shaping THz waves and enable chip-scale spintronic THz optics, sensing, and imaging.
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http://dx.doi.org/10.1088/1361-6528/abcc98DOI Listing
March 2021

Unraveling the Nature of Excellent Potassium Storage in Small-Molecule Se@Peapod-Like N-Doped Carbon Nanofibers.

Adv Mater 2020 Dec 18;32(52):e2003879. Epub 2020 Nov 18.

Hefei National Laboratory for Physical Sciences at the Microscale, Department of Materials Science and Engineering, CAS Key Laboratory of Materials for Energy Conversion, University of Science and Technology of China, Hefei, Anhui, 230026, China.

The potassium-selenium (K-Se) battery is considered as an alternative solution for stationary energy storage because of abundant resource of K. However, the detailed mechanism of the energy storage process is yet to be unraveled. Herein, the findings in probing the working mechanism of the K-ion storage in Se cathode are reported using both experimental and computational approaches. A flexible K-Se battery is prepared by employing the small-molecule Se embedded in freestanding N -doped porous carbon nanofibers thin film (Se@NPCFs) as cathode. The reaction mechanisms are elucidated by identifying the existence of short-chain molecular Se encapsulated inside the microporous host, which transforms to K Se by a two-step conversion reaction via an "all-solid-state" electrochemical process in the carbonate electrolyte system. Through the whole reaction, the generation of polyselenides (K Se , 3 ≤ n ≤ 8) is effectively suppressed by electrochemical reaction dominated by Se molecules, thus significantly enhancing the utilization of Se and effecting the voltage platform of the K-Se battery. This work offers a practical pathway to optimize the K-Se battery performance through structure engineering and manipulation of selenium chemistry for the formation of selective species and reveal its internal reaction mechanism in the carbonate electrolyte.
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http://dx.doi.org/10.1002/adma.202003879DOI Listing
December 2020

Boosting Potassium Storage by Integration Advantageous of Defect Engineering and Spatial Confinement: A Case Study of Sb Se.

Small 2020 Dec 17;16(49):e2005272. Epub 2020 Nov 17.

Hefei National Laboratory for Physical Sciences at the Microscale, Department of Materials Science and Engineering, CAS Key Laboratory of Materials for Energy Conversion, University of Science and Technology of China, Hefei, Anhui, 230026, China.

The potassium ion batteries (KIBs) based on conversion/alloying reaction mechanisms show high theoretical capacity. However, their applications are hampered by the poor cyclability resulting from the inherent large volume variations and the sluggish kinetics during K repeated insertion/extraction process. Herein, taken Sb Se as a model material, by rational design, nickel doped-carbon coated Sb Se nanorods (denoted as (Sb Ni ) Se @C) are prepared through combined strategies of the conductive encapsulation and crystal structure modification. The carbon coating acts as an efficient buffer layer that maintains superior structural stability upon cycling. The introduction of Ni atoms can enhance electrical conductivity, leading to outstanding rate performance, which are confirmed by density functional theory calculation. The (Sb Ni ) Se @C displays excellent reversible capacity (410 mAh g at 0.1 A g after 100 cycles) and unprecedented rate capability (140 mAh g at 10 A g ). Furthermore, KFeHCF//(Sb Ni ) Se @C full cell exhibits a high specific capacity (408 mAh g at 0.1 A g ), superior rate capability (260 mAh g at 2 A g ). This work can open up a new avenue for the design of stable conversion/alloying-based anodes for high energy density KIBs.
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http://dx.doi.org/10.1002/smll.202005272DOI Listing
December 2020

Prognostic value of tumor infiltrating lymphocytes combined with PD-L1 expression for patients with solitary colorectal cancer liver metastasis.

Ann Transl Med 2020 Oct;8(19):1221

Department of Medicine Laboratory, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine Guangzhou, China.

Background: The aim of this study was to assess the prognostic value of CD8+ tumor infiltrating lymphocytes (TIL) combined with programmed cell death-ligand 1 (PD-L1) expression for patients with solitary colorectal cancer liver metastasis (SCLM) undergoing R0 resection.

Methods: Patients undergoing curative hepatectomy for SCLM were reviewed. Immunohistochemical multiplex technique was used for quantifying CD8+ TIL, and immunohistochemical staining was used for assessing PD-L1 expression. The tumor immune microenvironment (TIME) was classified as strong for high CD8+ TIL and low PD-L1, weak for low CD8+ TIL and high PD-L1, and mild for the rest. Recurrence-free survival (RFS) and overall survival (OS) was compared between these groups.

Results: Among the 94 patients included, a high CD8+ TIL and high PD-L1 expression was observed in 51 (54.3%) and 47 (50.0%) patients, respectively. Strong, mild, and weak TIME was observed in 24 (25.5%), 42 (44.7%), and 28 (29.8%) patients, respectively. Patients with a high CD8+ TIL had a significant longer RFS than patients with a low CD8+ TIL (3-year RFS rate, 71.6% 55.3%, P=0.018). The 3-year RFS rate in the strong TIME group was significantly higher than that in the mild and weak TIME groups (89.5% 71.7% and 28.8%, P<0.001), as was the 3-year rate of OS (93.8% 81.8% and 61.6%, P<0.001). CD8+ TIL combined with PD-L1 expression showed better predicting accuracy for RFS than CD8+ TIL alone.

Conclusions: The density of CD8+ TIL combined with PD-L1 expression in liver metastasis was a predictor of RFS for patients with SCLM undergoing R0 resection, and therefore can be used for guiding the postoperative treatment of these patients.
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http://dx.doi.org/10.21037/atm-20-2762aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7607072PMC
October 2020

Surface selectivity of NiS toward hydrogen evolution reaction: a first-principles study.

Phys Chem Chem Phys 2020 Nov;22(44):25685-25694

State Key Laboratory of Information Photonics and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, P. R. China.

Exploring materials with high catalytic performance toward hydrogen evolution reaction (HER) is of importance for the development of clean hydrogen energy, and their surface structure is essential for this function. In this study, using density functional theory (DFT), we reported a comprehensive study on the phase stability, surface structures, electronic properties and HER catalytic properties of the low-index surfaces of Ni3S2, including the (0001), (101[combining macron]0), (101[combining macron]1), (112[combining macron]0) and (112[combining macron]1) planes with different terminations. Our calculated results demonstrate that S-rich surfaces and several stoichiometric surfaces of Ni3S2 are thermodynamically stable, including (0001)A, (101[combining macron]0)A, (112[combining macron]0)C, (101[combining macron]0)C, (101[combining macron]0)B and (112[combining macron]1)A surfaces. Among the six stable surface structures, the (0001)A, (101[combining macron]0)B and (101[combining macron]0)C surfaces of Ni3S2 are indispensable for high HER performance because of their high catalytic activity, suitable potential and high thermodynamic stability. The calculated changes of Gibbs free energy (ΔGH*) of the Top S2 site on (0001)A, Hollow Ni2S3S4 site on (101[combining macron]0)C, and Bridge Ni1Ni3 site and Hollow Ni2S1S2 site on (101[combining macron]0)B are -0.143, 0.122, 0.012, and -0.112 eV, respectively, comparable with or even better than those of Pt(111) (-0.07 eV). In addition, the possible Volmer-Heyrovsky and Volmer-Tafel processes on the considered surfaces are also investigated. When the overpotential is in the range of 0 to 300 mV, the density of active sites on the (101[combining macron]0)B surface of Ni3S2 is found to be the highest. This work provides significant insights on the surface selectivity of Ni3S2 toward HER and provides a route to optimize the performance of Ni3S2 with exposed surfaces.
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http://dx.doi.org/10.1039/d0cp03845hDOI Listing
November 2020