Topological-Defect-Induced Superstructures on Graphite Surface

Topological defects in graphene induce structural and electronic modulations.Knowing exact nature of brokensymmetry states around the individual atomic defects of graphene is very important for understanding the electronic properties of this material.We investigate structural dependence on localized electronic states in the vicinity of topological defects on a highly oriented pyrolytic graphite(HOPG)surface,using scanning tunneling microscopy and spectroscopy.Several inherent topological defects on the HOPG surface and the local density of states surrounding them are explored,visualized as scattering wave-related(√3×√3)R30∘superstructures and honeycomb superstructures.In addition,the superstructures observed near the grain boundary have a much higher decay length at specific sites than that reported previously,indicating far greater electron scattering on the quasi-periodic grain boundary.

Association of Cytokines with Alanine Aminotransferase, Hepatitis B Virus Surface Antigen and Hepatitis B Envelope Antigen Levels in Chronic Hepatitis B

Background： Cytokines play an important role in occorrence and recovery of hepatitis B virus （HBV） infection. The aim of this study was to investigate the changes ofcytokines concentration and its correlation to alanine aminotransferase （ALT）, HBV deoxyribonucleic acid （HBV-DNA）, hepatitis B envelope antigen （HBeAg）, and HBV surface antigen （HBsAg） in the development of chronic hepatitis B （CHB）. Methods： Thirteen healthy individuals （HI）, 30 chronic HBV-infected patients in immune tolerant （IT） phase, and 55 CHB patients were enrolled between August 2015 and May 2017. The peripheral blood samples were collected from all individuals. Tile levels of interferon （IFN）-α2, interleukin （IL）-10, transforming growth factor （TGF）-β1, HBV-DNA, HBsAg, and HBeAg and liver function were measured. The quantitative determinations of cytokines levels, including I FN-ct2, IL-10, and TGF-[31 were performed using Luminex multiplex technology. The correlation of cytokines to ALT, HBV-DNA, HBsAg, and HBeAg was analyzed by linear regression analysis. Results： IFN-ct2 levels were similar between HI and IT groups （15.35 [5.70, 67.65] pg/ml vs. 15.24 [4.07, 30.73] pg/ml, Z = -0.610, P - 0.542）, while it elevated significantly in CH B group （35.29 [ 15.94, 70.15] pg/ml vs. 15.24 [4.07, 30.73] pg/ml; Z = -2.522, P = 0.012）. Compared with HI group （3.73 [2.98, 11.92] pg/ml）, IL-10 concentrations in IT group （5.02 [2,98, 10.11] pg/ml）, and CHB group （7.48 [3. I 0, 18.00] pg/ml） slightly increased （X^2 = 2.015, P - 0.365）, and there was no significant difference between IT and CHB group （Z =- 1.419, P = 0.156）. The TGF-β1 levels among HI （3.59 ±0.20 pg/ml）, IT （3.62 ±0.55 pg/ml）, and CHB groups （3.64±0.30 pg/ml） were similar （X^2=2.739, P = 0.254）. In all chronic HBV-infected patients （including patients in IT and CHB groups）, the elevation of IFN-α2 level was significantly associated with ALT level （β = 0.389, t = 2.423, P = 0.018）, and was also negatively correlated to HBV-DNA load （β = -0.358, t=-2.308, P = 0.024）, HBsAg （β = -0.359, t = -2.288, P = 0.025）, and HBeAg contents （β = -0.355, t = -2.258, P = 0.027）. However, when both ALT level and cytokines were included as independent variable, HBV-DNA load, HBsAg, and HBeAg contents were only correlated to ALT level （[β= -0.459, t = -4.225, P = 0.000; β = -0.616, t = -6.334, P = 0.000; and β = -0.290, t = -2.433, P = 0.018; respectively）. Conclusions： IFN-α2 elevation was associated with ALT level in patients with chronic HBV infection. However, in CHB patients, only ALT level was correlated to HBV-DNA, HBsAg and HBeAg contents.

Plasmacytoid Dendritic Cell Function and Cytokine Network Profiles in Patients with Acute or Chronic Hepatitis B Virus Infection

Background： Plasmacytoid dendritic cells （pDCs） and cytokines play an important role in occurrence and recovery of hepatitis B virus （HBV） infection. The aim of this study was to explore the frequency and function ofpDC and serum cytokine network profiles in patients with acute or chronic HBV infection. Methods： The healthy individuals （HI group）, hepatitis B envelope antigen （HBeAg）-positive chronic HBV patients in immune tolerance （IT） phase （IT group）, HBeAg-positive chronic HBV patients （CHB group）, and acute HBV patients （AHB group） were enrolled in this study. The frequency of cluster of differentiation antigen 86 （CD86） ＋ pDC and the counts of CD86 molecular expressed on surface ofpDC were tested by flow cytometer. The quantitative determinations ofcytokines, including Fins-like tyrosine kinase 3 ligand （FIt-3L）, interferon （1FN）-α2, IFN-γ, interleukin （IL）-17A, IL-6, IL-10, transforming growth factor （TGF）-β1 and TGF-β2, were performed using Luminex multiplex technology. Results： In this study, there were 13 patients in HI group, 30 in IT group, 50 in CHB group, and 32 in AHB group. Compared with HI group, HBV infected group （including all patients in IT, CHB and AHB groups） had significantly higher counts of CD86 molecular expressed on the surface ofpDC （4596.5 ± 896.5 vs. 7097.7 ± 3124.6; P 〈 0.001）. The counts of CD86 molecular expressed on the surface of pDC in CriB group （7739.2 ±4125.4） was significantly higher than that of IT group （6393.4 ± 1653.6, P=0.043）. Compared with IT group, the profile of cytokines of FIt-3L, IFN-γ, and IL-17A was decreased, IFN-α2 was significantly increased （P =0.012） in CH B group. The contents of IL-10, TGF-{31, and TGF-132 in AHB group were significantly increased compared with IT and CHB groups （all P 〈 0.05）. Conclusions： This study demonstrated that the function of pDC was unaffected in HBV infection. The enhanced function of pDC and IFN-α2 might involve triggering the immune response from IT to hepatitis active phase in H BV infection. Acute patients mainly presented as down-regulation of the immune response by enhanced IL-10 and TGF-β.