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Huang L, Zheng F, Deng Q, Thi QH, Wong LW, Cai Y, Wang N, Lee CS, Lau SP, Chhowalla M, Li J, Ly TH, Zhao J. In Situ Scanning Transmission Electron Microscopy Observations of Fracture at the Atomic Scale. PHYSICAL REVIEW LETTERS 2020; 125:246102. [PMID: 33412019 DOI: 10.1103/physrevlett.125.246102] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 09/10/2020] [Accepted: 10/16/2020] [Indexed: 06/12/2023]
Abstract
The formation, propagation, and structure of nanoscale cracks determine the failure mechanics of engineered materials. Herein, we have captured, with atomic resolution and in real time, unit cell-by-unit cell lattice-trapped cracking in two-dimensional (2D) rhenium disulfide (ReS_{2}) using in situ aberration corrected scanning transmission electron microscopy (STEM). Our real time observations of atomic configurations and corresponding strain fields in propagating cracks directly reveal the atomistic fracture mechanisms. The entirely brittle fracture with non-blunted crack tips as well as perfect healing of cracks have been observed. The mode I fracture toughness of 2D ReS_{2} is measured. Our experiments have bridged the linear elastic deformation zone and the ultimate nm-sized nonlinear deformation zone inside the crack tip. The dynamics of fracture has been explained by the atomic lattice trapping model. The direct visualization on the strain field in the ongoing crack tips and the gained insights of discrete bond breaking or healing in cracks will facilitate deeper insights into how atoms are able to withstand exceptionally large strains at the crack tips.
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Valestrand L, Berntsen NL, Zheng F, Schrumpf E, Hansen SH, Karlsen TH, Blumberg RS, Hov JR, Jiang X, Melum E. Lipid antigens in bile from patients with chronic liver diseases activate natural killer T cells. Clin Exp Immunol 2020; 203:304-314. [PMID: 33089489 DOI: 10.1111/cei.13541] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 12/16/2022] Open
Abstract
Natural killer T (NKT) cells are an abundant subset of liver lymphocytes activated by lipid antigens presented on CD1d molecules that are expressed by cholangiocytes. We aimed to determine if bile from patients with chronic liver diseases contains antigenic lipids that can activate NKT cells. Using murine invariant (24.7, 24.8 and DN32.D3) and non-invariant (14S.6, 14S.7 and 14S.10) NKT hybridomas we investigated the presence of lipid antigens in bile collected from the gallbladder of patients undergoing liver transplantation due to end-stage liver disease. Biliary microbiota profiles were generated using 16S rRNA amplicon sequencing. We found that the patient bile samples contain antigens that activate both invariant and non-invariant NKT hybridomas (24.7, 24.8, DN32.D3, 14S.6, 14S.7 and 14S.10), as demonstrated by activation of at least one hybridoma by eight of 10 bile samples. Activation at high dilutions suggests that some antigens are highly potent. We used the non-invariant NKT hybridoma 14S.6 to screen 21 additional patient bile samples for NKT-reactivity and demonstrated that 12 of 21 bile samples resulted in activation, three of which gave a strong activation. Four of 12 activating bile samples contained microbial DNA. Our results reveal an immunological pathway that could be of critical importance in biliary immunology.
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Jiang L, Li X, Zhang J, Li W, Dong F, Chen C, Lin Q, Zhang C, Zheng F, Yan W, Zheng Y, Wu X, Xu B. Combined LATTICE-based Partial Radio-ablation and Immune checkpoint blockade for Advanced Bulky Tumors: The Concept and a Case Report. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.1421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Huang L, Zheng F, Deng Q, Thi QH, Wong LW, Cai Y, Wang N, Lee CS, Lau SP, Ly TH, Zhao J. Anomalous fracture in two-dimensional rhenium disulfide. SCIENCE ADVANCES 2020; 6:eabc2282. [PMID: 33208360 PMCID: PMC7673817 DOI: 10.1126/sciadv.abc2282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 09/29/2020] [Indexed: 05/22/2023]
Abstract
Low-dimensional materials usually exhibit mechanical properties from those of their bulk counterparts. Here, we show in two-dimensional (2D) rhenium disulfide (ReS2) that the fracture processes are dominated by a variety of previously unidentified phenomena, which are not present in bulk materials. Through direct transmission electron microscopy observations at the atomic scale, the structures close to the brittle crack tip zones are clearly revealed. Notably, the lattice reconstructions initiated at the postcrack edges can impose additional strain on the crack tips, modifying the fracture toughness of this material. Moreover, the monatomic thickness allows the restacking of postcrack edges in the shear strain-dominated cracks, which is potentially useful for the rational design of 2D stacking contacts in atomic width. Our studies provide critical insights into the atomistic processes of fracture and unveil the origin of the brittleness in the 2D materials.
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Zheng F, Huang L, Wong L, Han J, Cai Y, Wang N, Deng Q, Ly TH, Zhao J. The Mobile and Pinned Grain Boundaries in 2D Monoclinic Rhenium Disulfide. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2001742. [PMID: 33240756 PMCID: PMC7675180 DOI: 10.1002/advs.202001742] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/23/2020] [Indexed: 05/28/2023]
Abstract
In bulk crystals, the kinetics of dislocations is usually hindered by the twining boundaries (TB) or grain boundaries (GB), rendering the well-known grain boundary strengthening effects. Nevertheless, here it is found that in 2D rhenium disulfide (ReS2), twinning is much easier than dislocation slip. Consequently, the highly mobile TBs or GBs are inversely pinned by the relatively immobile dislocations. Due to the strong in-plane covalent bonding, the GBs in high-symmetry 2D materials such as graphene which consists of defects are immobile at room temperature. In contrast, in monoclinic 2D ReS2 several types of GBs (including TBs) can be readily generated and driven by mechanical loading. A complete library of the GBs in 2D ReS2 is established by the (in situ) atomic-scale transmission electron microscopy (TEM) characterizations and density functional theory (DFT) calculations. The twinning (shear) stresses for 2D ReS2 are estimated as low as 4-30 MPa, one or two orders of magnitude lower than the traditional bulk materials. Full elucidation on the GB structures and especially the intriguing GB kinetics in such anisotropic 2D materials are of fundamental importance to understand the structure-property relationships and develop strain-tunable applications for 2D materials in future.
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Liu B, Xu Q, Wang Q, Feng S, Lai F, Wang P, Zheng F, Xiang Y, Wu J, Nie J, Qiu C, Xia W, Li L, Yu G, Lin Z, Xu K, Xiong Z, Kong F, Liu L, Huang C, Yu Y, Na J, Xie W. The landscape of RNA Pol II binding reveals a stepwise transition during ZGA. Nature 2020; 587:139-144. [PMID: 33116310 DOI: 10.1038/s41586-020-2847-y] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Accepted: 08/04/2020] [Indexed: 12/22/2022]
Abstract
Zygotic genome activation (ZGA) is the first transcription event in life1. However, it is unclear how RNA polymerase is engaged in initiating ZGA in mammals. Here, by developing small-scale Tn5-assisted chromatin cleavage with sequencing (Stacc-seq), we investigated the landscapes of RNA polymerase II (Pol II) binding in mouse embryos. We found that Pol II undergoes 'loading', 'pre-configuration', and 'production' during the transition from minor ZGA to major ZGA. After fertilization, Pol II is preferentially loaded to CG-rich promoters and accessible distal regions in one-cell embryos (loading), in part shaped by the inherited parental epigenome. Pol II then initiates relocation to future gene targets before genome activation (pre-configuration), where it later engages in full transcription elongation upon major ZGA (production). Pol II also maintains low poising at inactive promoters after major ZGA until the blastocyst stage, coinciding with the loss of promoter epigenetic silencing factors. Notably, inhibition of minor ZGA impairs the Pol II pre-configuration and embryonic development, accompanied by aberrant retention of Pol II and ectopic expression of one-cell targets upon major ZGA. Hence, stepwise transition of Pol II occurs when mammalian life begins, and minor ZGA has a key role in the pre-configuration of transcription machinery and chromatin for genome activation.
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Zheng F, Zhou J, Wang C, Hu W, Krischek B. There may be no significant increase of cerebrospinal fluid tyrosine levels in patients with Parkinson's disease. Eur J Neurol 2020; 28:e15-e16. [PMID: 33025700 DOI: 10.1111/ene.14570] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 09/04/2020] [Indexed: 01/05/2023]
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Chen XH, Shi ZG, Lin HB, Wu F, Zheng F, Wu CF, Huang MW. Resveratrol alleviates osteoporosis through improving the osteogenic differentiation of bone marrow mesenchymal stem cells. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2020; 23:6352-6359. [PMID: 31364143 DOI: 10.26355/eurrev_201907_18459] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE To investigate the protective effect of Resveratrol (RES) on TNF-α-induced inhibition of osteogenic differentiation, thus alleviating the progression of osteoporosis (OP). MATERIALS AND METHODS OP model in rats was first conducted by performing ovariectomy (OVX). Rats were randomly divided into sham group, OVX group, and RES+OVX group. Body weight of each rat was regularly recorded every week. Bone mineral density (BMD) of rat femoral metaphysis was measured by micro-CT. Changes in radial degrees and loads of rat femora were examined through three-point bending experiments. Relative levels of OCN and Runx2 in each group were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Alkaline phosphatase (ALP) activity and calcification ability were assessed through ALP staining and alizarin red staining, respectively. Bone mesenchymal stem cells (BMSCs) were extracted from healthy rats and divided into control group, Tumor necrosis factor-α (TNF-α) group, RES group, and TNF-α+RES group based on different treatments. Relative levels of OCN and Runx2, ALP activity, and calcification ability in each group were detected in the same way. Finally, protein levels of NF-κB and β-catenin in BMSCs were determined. RESULTS Rats in each group gained body weight during the experimental period, especially those in OVX group and RES+OVX group. No significant difference in the body weight was found between OVX group and RES+OVX group. BMD in rat femora of RES+OVX group was higher than in OVX group but lower than sham group. Elastic/max radial degree and elastic/max load of femora were markedly reduced in OVX group compared to RES+OVX group. Relative levels of OCN and Runx2, ALP activity and calcification ability decreased in OVX group relative to sham group, which were partially reversed by RES treatment. After osteogenic differentiation in BMSCs induced with TNF-α, viability and calcification ability were markedly reduced and were upregulated by RES treatment. Moreover, RES treatment enhanced the downregulated levels of OCN and Runx2 in BMSCs undergoing TNF-α induction. Upregulated protein levels of nuclear factor kappa-B (NF-κB) and β-catenin in TNF-α-induced BMSCs were downregulated by RES treatment. CONCLUSIONS The inhibited osteogenic differentiation of BMSCs undergoing TNF-α induction is improved by resveratrol treatment, which contributes to alleviate the progression of osteoporosis.
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Zheng F, Zhai XL, Wang WJ, Guo KP, Xiao CC, Ni QC. [Expression and clinical significance of LRFN4 in colorectal cancer tissue]. ZHONGHUA YI XUE ZA ZHI 2020; 100:1745-1749. [PMID: 32536098 DOI: 10.3760/cma.j.cn112137-20190905-01975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the expression and clinical significance of LRFN4 in colorectal cancer. Methods: A total of 210 cases of colorectal cancer tissues and 228 cases of corresponding surgical margin tissues were collected. Immunohistochemistry was employed to evaluate the expression of LRFN4 in colorectal cancer.The correlation between LRFN4 expression and clinicopathological features of colorectal cancer as well as patient outcome were analyzed. Results: The positive rate of LRFN4 in colorectal cancer and in non-cancer was 55.24%(116/210), and 37.28% (85/228) , respectively.The expression of LRFN4 in colorectal cancer tissues was higher than that in non-cancer tissues(χ(2)=14.196, P<0.001). High expression of LRFN4 was significantly correlated with tumor location(χ(2)=4.133,P=0.042), T staging(χ(2)=6.494,P=0.039), N staging(χ(2)=11.715,P=0.008), TNM staging(χ(2)=13.398,P=0.004), CEA (χ(2)=6.017, P=0.049), but without gender, age, degree of differentiation, M staging(P>0.05).The Kaplan-Meier survival curves indicated that high LRFN4 expression was associated with good survival (P<0.05). In addition, Cox proportional hazards model showed that the high expression of LRFN4(HR=0.585, P=0.018)was an independent risk factor for prognosis in patients with colorectal cancer. Conclusions: The expression of LRFN4 is up-regulated in colorectal cancer, which is significantly correlated with the clinicopathological features and prognosis. High expression of LRFN4 reduced the risk of death in patients with colorectal cancer.
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Long WG, Zhuang Y, Li M, Zheng F, Zhong AJ, Wang DQ, Wu JN. [Gastroblastoma: report of a case]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2020; 49:761-763. [PMID: 32610398 DOI: 10.3760/cma.j.cn112151-20191016-00564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Huang L, Thi QH, Zheng F, Chen X, Chu YW, Lee CS, Zhao J, Ly TH. Catalyzed Kinetic Growth in Two-Dimensional MoS2. J Am Chem Soc 2020; 142:13130-13135. [DOI: 10.1021/jacs.0c05057] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zhu J, Tran L, Zheng F, James J, Guthridge J, Chong B. 717 Enhanced molecular signatures in cutaneous lupus erythematosus patients support distinct pathogenic pathways in African American patients. J Invest Dermatol 2020. [DOI: 10.1016/j.jid.2020.03.730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sun Y, Wang W, Zheng F, Zhang S, Wang F, Liu S. Phytotoxicity of iron-based materials in mung bean: Seed germination tests. CHEMOSPHERE 2020; 251:126432. [PMID: 32169709 DOI: 10.1016/j.chemosphere.2020.126432] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 03/03/2020] [Accepted: 03/05/2020] [Indexed: 05/21/2023]
Abstract
Environmental applications and potential risks of iron-based materials have attracted increasing attention. However, most previous studies focused on a single material. Comparative research using different iron-based materials under the same experimental conditions is still lacking. Here, six iron-based materials, including micro-sized and nanoscale Fe3O4 (i.e., mFe3O4 and nFe3O4), bulk and bare nanoscale zero-valent iron (i.e., mZVI and B-nZVI), starch-supported nZVI (S-nZVI), and activated carbon-supported nZVI (A-nZVI), were studied to compare their phytotoxicity in mung bean grown in suspensions with doses of 0, 300, 600 and 1000 mg/L. Taking the four toxicology parameters (seed germination rate, germination index, seedling elongation and biomass) together, the iron-based materials except mFe3O4 generally produced no significant phytotoxicity to mung bean even at 1000 mg/L. nFe3O4 and B-nZVI showed no higher phytotoxicity than their micro-sized counterparts (mFe3O4 and mZVI). All the materials resulted in increased Fe concentrations in seedlings particularly in roots, and mZVI and B-nZVI produced more significant effects. However, the Fe in the roots was difficultly translocated to the shoots. Compared to B-nZVI, nFe3O4 had lower bioavailability and bioaccumulation potential. XRD results confirmed that most Fe3O4 and B-nZVI remained unchanged during seedling growth, while support materials accelerated the corrosion and transformation of S-nZVI and A-nZVI. In conclusion, the tested nanoscale iron-based materials generally possess no obvious phytotoxicity within the dose range, but cause excess Fe accumulation in seedlings. Introduction of support materials may reduce such risk, allowing safer applications of these iron-based materials.
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Dong X, Zheng F, Liu X, Zhang L, Hu R, Wang L, Hao X, Xue P. Simultaneous Quantitative Analysis of Q-Marker with One Single Reference in Glycyrrhiza uralensis Fisch. J Chromatogr Sci 2020; 58:511-519. [PMID: 32266386 DOI: 10.1093/chromsci/bmaa015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 02/06/2020] [Accepted: 02/26/2020] [Indexed: 11/14/2022]
Abstract
In traditional Chinese medicine (TCM) studies, it is difficult to choose evaluation markers for the strict quality control of herbs. A high performance liquid chromatography coupled with metabolomics for simultaneous quantitative analysis of quality markers (Q-markers) in Glycyrrhiza uralensis Fisch was established, which could not only ensure the quality and batch-to-batch consistency of TCMs, but also achieve a quantitative analysis of multi-components by the single reference standard. Based on the construction of chromatographic profiles by high performance liquid chromatography (HPLC) and HPLC-Q-Exactive/MS methods, different multivariate analyses were employed. Seven quantitative indices were selected as the Q-markers, and a reliable quantification method was established. The quantitative method was acceptable with good linearity with correlation coefficients >0.9993 and satisfactory repeatability (relative standard deviation (RSD) < 0.05%), precision (RSD < 0.24%), reproducibility (RSD < 0.97%), stability (RSD < 2.52%) and recoveries (96.96%-98.52%, RSD < 3.24%), and no significant differences were observed between the external standard method and the new method as determined by calculating standard method difference. Overall, the study suggests that the simultaneous quantitative analysis of main Q-marker in G. uralensis Fisch with one single marker can be considered good quality criteria for performing quality control of G. uralensis Fisch.
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Zheng F, Luo L, Wang J, Huang T, Huang J, Wang C, Hu W, Krischek B. Non-vitamin-K oral anticoagulants may not significantly reduce the risk of fatal or disabling stroke compared with warfarin. Eur J Neurol 2020; 27:e57. [PMID: 32441879 DOI: 10.1111/ene.14356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 04/30/2020] [Indexed: 11/29/2022]
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Zheng F, Tang W, Li H, Huang YX, Xie YL, Zhou ZG. Clinical characteristics of 161 cases of corona virus disease 2019 (COVID-19) in Changsha. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2020; 24:3404-3410. [PMID: 32271459 DOI: 10.26355/eurrev_202003_20711] [Citation(s) in RCA: 118] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE In December 2019, a new type of coronavirus-infected pneumonia broke out in Wuhan and spread rapidly to other parts of the country. The purpose of this study was to investigate the clinical features of coronavirus disease 2019 (COVID-19). MATERIALS AND METHODS A retrospective analysis was performed on the confirmed cases of COVID-19, who were admitted to the North Hospital of Changsha first Hospital (Changsha Public Health treatment Center) from January 17 to February 7, 2020. RESULTS The median age of COVID-19 patients was 45 years (range 33.5-57). The male patients accounted for 49.7%, 64.6% of the patients had a history of exposure in Wuhan, and 31.7% had family aggregation. The median days of onset were six, and the incidence of severe illness was 18.6%. Compared with the non-severe group, the severe group showed statistical significance in older age, hypertension, bilateral lung plaque shadow, decrease in lymphocyte count, increase in C-reactive protein (CRP), aspartate aminotransferase (AST), lactate dehydrogenase, and creatine kinase. CONCLUSIONS Age, combined hypertension, oxygenation index, double lung patch, decreased lymphocyte count, and elevated levels of C-reactive protein, aspartate aminotransferase, lactate dehydrogenase, and creatine kinase can be used as predictors of the disease severity.
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Sun Y, Zheng F, Wang W, Zhang S, Wang F. Remediation of Cr(VI)-Contaminated Soil by Nano-Zero-Valent Iron in Combination with Biochar or Humic Acid and the Consequences for Plant Performance. TOXICS 2020; 8:E26. [PMID: 32260118 PMCID: PMC7357137 DOI: 10.3390/toxics8020026] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 04/01/2020] [Indexed: 12/11/2022]
Abstract
Nano-scale zero-valent iron (nZVI) is among the most common nanoparticles widely used for the treatment of various environmental contaminants. However, little is known about the combined effects of nano-zero-valent iron (nZVI) and other soil amendments on soil remediation and plant performance. For the first time, we studied the remediation of Cr(VI)-contaminated soil using bare nZVI (B-nZVI) and starch-supported nZVI (S-nZVI) in combination with either biochar (BC) or humic acid (HA), and the consequent effects on plant growth and Cr accumulation. Both S-nZVI and B-nZVI decreased the contents of Cr(VI) and available Cr in soil, but increased available Fe content, with S-nZVI generally showing more pronounced effects at a higher dose (1000 mg/kg). B-nZVI exerted no inhibition and even stimulation on plant growth, but 1000 mg/kg S-nZVI produced significant phytotoxicity, resulting in decreased plant growth, low chlorophyll content in leaves, and excessive accumulation of Fe in roots. Each nZVI decreased shoot and root Cr concentrations. BC and HA produced synergistic effects with nZVI on Cr(VI) removal from soil, but HA decreased soil pH and increased the availability of Cr and Fe, implying a potential environmental risk. Addition of BC or HA did not alter the effects of either nZVI on plant growth. In conclusion, combined application of 100 mg/kg nZVI and BC could be an ideal strategy for the remediation of soil contaminated with Cr(VI), whereas high-dose S-nZVI and HA are not recommended in the remediation of agricultural soils for crop production or in the phytostabilization of Cr(VI).
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Zheng F, Thi QH, Wong LW, Deng Q, Ly TH, Zhao J. Critical Stable Length in Wrinkles of Two-Dimensional Materials. ACS NANO 2020; 14:2137-2144. [PMID: 31951371 DOI: 10.1021/acsnano.9b08928] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The emergent two-dimensional (2D) materials are atomically thin and ultraflexible, promising for a variety of miniaturized, high-performance, and flexible devices in applications. On one hand, the ultrahigh flexibility causes problems: the prevalent wrinkles in 2D materials may undermine the ideal properties and create barriers in fabrication, processing, and quality control of materials. On the other hand, in some cases the wrinkles are used for the architecturing of surface texture and the modulation of physical/chemical properties. Therefore, a thorough understanding of the mechanism and stability of wrinkles is highly needed. Herein, we report a critical length for stabilizing the wrinkles in 2D materials, observed in the wrinkling and wrinkle elimination processes upon thermal annealing as well as by our in situ TEM manipulations on individual wrinkles, which directly capture the evolving wrinkles with variable lengths. The experiments, mechanical modeling, and self-consistent charge density functional tight binding (SCC-DFTB) simulations reveal that a minimum critical length is required for stabilizing the wrinkles in 2D materials. Wrinkles with lengths below a critical value are unstable and removable by thermal annealing, while wrinkles with lengths above a critical value are self-stabilized by van der Waals interactions. It additionally confirms the pronounced frictional effects in wrinkles with lengths above critical value during dynamical movement or sliding.
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Xu H, Chen W, Zheng F, Tang D, Liu D, Wang G, Xu Y, Yin L, Zhang X, Dai Y. Reconstruction and analysis of the aberrant lncRNA-miRNA-mRNA network in systemic lupus erythematosus. Lupus 2020; 29:398-406. [PMID: 32070185 DOI: 10.1177/0961203320908927] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE A new perspective of determining the pathophysiology of systemic lupus erythematosus (SLE) development is required. The current study explores the aberrant expression of long non-coding RNAs (lncRNA), microRNA (miRNA) and mRNA. The study further constructs and analyses the lncRNA-miRNA-mRNA network to elucidate their gene regulation roles in SLE. METHOD We extracted mRNA, lncRNA and miRNA from the whole venous blood of 20 SLE patients and 20 normal control (NC) healthy individuals. A lncRNA-mRNA-miRNA network in SLE was constructed using a bioinformatics approach. Subsequently, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed using the Cytoscape plug-in BinGo, the DAVID database and Cytoscape software to explore the function of mRNAs in this network. RESULT A total of 855 mRNA, 7311 lncRNA and 134 miRNA with differentially expressed profiles were identified. Meanwhile, we established a competing endogenous RNA (ceRNA) subnetwork composed of 52 differentially expressed lncRNAs (DElncRNAs), seven differentially expressed miRNAs and 10 differentially expressed mRNAs. We extracted the subnetwork from the ceRNA network and found that three novel miRNAs were key: hsa-miR-145, hsa-miR-17 and hsa-miR-143. We also deduced that the DElncRNAs MIAT and NEAT1 might play crucial roles in the pathogenesis of SLE. The results were verified by bioinformatics analysis. CONCLUSION Our results provide a novel perspective for studying lncRNA-related and miRNA-related ceRNA networks in SLE.
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Sun Y, Jing R, Zheng F, Zhang S, Jiao W, Wang F. Evaluating phytotoxicity of bare and starch-stabilized zero-valent iron nanoparticles in mung bean. CHEMOSPHERE 2019; 236:124336. [PMID: 31310976 DOI: 10.1016/j.chemosphere.2019.07.067] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 07/04/2019] [Accepted: 07/08/2019] [Indexed: 06/10/2023]
Abstract
Zero-valent iron nanoparticles (nZVI) are among the most widely used nanoparticles in nanoremediation of various environmental pollutants. Environmental fate and impact of nZVI has attracted increasing concerns due to their potential risks. However, phytotoxicity of nZVI still remains poorly understood. Here, the phytotoxic effects of bare nZVI (B-nZVI) and starch-stabilized nZVI (S-nZVI) were evaluated on the germination of mung bean seeds exposed to suspensions with different doses of 0-1000 mg/L and the growth of hydroponically cultured seedling at 600 mg/L. In most cases, B-nZVI had no inhibition on seed germination, and even promotion on shoot and root elongation. However, S-nZVI displayed dose-dependent effects, with a decreased germination rate at 600-750 mg/L. B-nZVI at 600 mg/L showed no obvious phytotoxic but even stimulatory effects on seedling growth. Comparatively, S-nZVI at 600 mg/L produced significant phytotoxicity on mung bean plants, leading to decreased seedling growth, altered nutritional balance, and excess Fe accumulation in roots (>400 mg/kg). S-nZVI were observed to form a coating of insoluble Fe(III) compounds on root surface. Simultaneously, some nZVI penetrated and accumulated into root cells, but did not move to shoots. In conclusion, B-nZVI easily aggregate into larger particles in solution, leading to decreased adhesion to root surface and lower uptake by roots, whereas the higher dispersity and hydrophilicity of S-nZVI makes them more readily be adhered to root surface forming a coating, and penetrated into roots, resulting in excess Fe accumulation, consequently interfering with root functions such as the adsorption and transport of water and nutrients.
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Chen S, Xie X, Zheng F, Wu S. Auto Focusing Method of Imaging System of Digital PCR Instrument Based on BP Neural Network. INT J PATTERN RECOGN 2019. [DOI: 10.1142/s0218001419540314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The digital PCR instrument is a digital instrument for amplifying specific DNA fragments. The problem studied in this paper is the autofocus problem of its electronic imaging device. Based on the analysis of existing SOM neural network autofocus scheme, we propose an improved scheme-BP neural network for autofocus. It directly takes the SOM input and the actual focus position as the input and output of the BP neural network, which eliminates the process of prior classification and then corresponding to the focus matrix in the original SOM scheme, saving time. The experimental results show that the traditional autofocus method has good focusing effect, but the speed is slow, and the universality of the BP neural network autofocus scheme is not good enough, but within a good accuracy range, the speed is faster. Compared to traditional focusing methods, the autofocus scheme designed in this paper successfully achieves faster focusing speed for biochips.
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Du CN, Sun YQ, Zheng F, Yang MF. [Primary cystic echinococcosis in the left femur: a case report]. ZHONGGUO XUE XI CHONG BING FANG ZHI ZA ZHI = CHINESE JOURNAL OF SCHISTOSOMIASIS CONTROL 2019; 32:110-112. [PMID: 32185941 DOI: 10.16250/j.32.1374.2019243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This article reported a case with primary cystic echinococcosis in the left femur.
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Wang Z, Yao YJ, Zheng F, Guan Z, Zhang L, Dong N, Qin WJ. Mir-138-5p acts as a tumor suppressor by targeting pyruvate dehydrogenase kinase 1 in human retinoblastoma. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2019; 21:5624-5629. [PMID: 29271995 DOI: 10.26355/eurrev_201712_14005] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE MicroRNAs have caught more attention for their role in tumor progression. Retinoblastoma (RB) is one of these ordinary malignant tumors. This study aims to identify whether mir-138-5p can regulate the development of RB, and find out its potential mechanism. MATERIALS AND METHODS Mir-138-5p expression in RB cells was monitored by RT-qPCR. Besides, the role of mir-138-5p in RB development was explored through function experiments in vitro. The potential mechanism was further explored by RT-qPCR, luciferase assay, and Western blot assay. RESULTS In our investigation, mir-138-5p was lower-expressed in RB cells than that in retinal pigment epithelial cells. Moreover, overexpression of mir-138-5p repressed cell viability, migration and invasion, and induced apoptosis of RB cells, while downregulated mir-138-5p increased cell viability, migration and invasion, and reduced apoptosis of RB cells. Furthermore, pyruvate dehydrogenase kinase 1 (PDK1) could be downregulated via overexpression of mir-138-5p, while PDK1 was upregulated via knockdown of mir-138-5p. CONCLUSIONS Our results suggested that mir-138-5p could repress the development of RB via suppressing PDK1, which may offer a new vision for interpreting the mechanism of RB tumorigenesis.
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Tang G, You P, Tai Q, Yang A, Cao J, Zheng F, Zhou Z, Zhao J, Chan PKL, Yan F. Solution-Phase Epitaxial Growth of Perovskite Films on 2D Material Flakes for High-Performance Solar Cells. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1807689. [PMID: 31033074 DOI: 10.1002/adma.201807689] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 03/04/2019] [Indexed: 06/09/2023]
Abstract
The quality of perovskite films is critical to the performance of perovskite solar cells. However, it is challenging to control the crystallinity and orientation of solution-processed perovskite films. Here, solution-phase van der Waals epitaxy growth of MAPbI3 perovskite films on MoS2 flakes is reported. Under transmission electron microscopy, in-plane coupling between the perovskite and the MoS2 crystal lattices is observed, leading to perovskite films with larger grain size, lower trap density, and preferential growth orientation along (110) normal to the MoS2 surface. In perovskite solar cells, when perovskite active layers are grown on MoS2 flakes coated on hole-transport layers, the power conversion efficiency is substantially enhanced for 15%, relatively, due to the increased crystallinity of the perovskite layer and the improved hole extraction and transfer rate at the interface. This work paves a way for preparing high-performance perovskite solar cells and other optoelectronic devices by introducing 2D materials as interfacial layers.
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Zhu ZC, Yang X, Zheng F, Zheng L, Xu TS. [Clinical study of cervical necrotizing fasciitis accompanied with descending necrotizing mediastinitis treated with cervical double parallel incision combined with mediastinoscope or thoracoscope]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 2019; 54:309-314. [PMID: 31091563 DOI: 10.3760/cma.j.issn.1002-0098.2019.05.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To summarize the experience of applying cervical double parallel incision combined with mediastinoscope or thoracoscope in the treatment of cervical necrotizing fasciitis (CNF) accompanied with descending necrotizing mediastinitis (DNM), so as to provide a reference for clinical practice. Methods: The clinical data of six patients with CNF accompanied with DNM who were admitted to the Department of Stomatology and the Department of Otolaryngology Head and Neck Surgery, The First People's Hospital of Changzhou from September 2014 to September 2018 were retrospectively analyzed. All of the six patients were confirmed by CT of neck and chest, among whom there were two males and four females aged from 48 to 73. Three patients were treated with cervical double parallel incision combined with mediastinoscope to be combined with cervical and thoracic drainage under general anesthesia while the other three with cervical double parallel incision combined with thoracoscope to be combined cervical and thoracic drainage under general anesthesia. The CT of neck and chest as well as infectious indicators including hematology, C-reactive protein (CRP) and procalcitonin (PCT) were reexamined during the postoperative period. Results: The cervical and thoracic combined drainage was unobstructed in all of the six patients, no secondary surgery was performed, and the infectious indicators gradually decreased. All patients had off-bed activities on the first day after the operation, were all cured and discharged after an average of 21 days (16 to 36 days) in hospital and followed up for an average of 18 months (4 to 30 months) after the operation. None of them experienced infection relapse, and they were all satisfied with the appearance of the cervical incision. Conclusions: Cervical double parallel incision combined with mediastinoscope or thoracoscope for the treatment of CNF accompanied with DNM has the advantages of complete drainage, small trauma, excellent efficacy and aesthetic operative area, thus being deserved to be clinically popularized.
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