Sodium butyrate reduces high-fat diet-induced non-alcoholic steatohepatitis through upregulation of hepatic GLP-1R expression

Da Zhou,Yuan-Wen Chen,Ze-Hua Zhao,Rui-Xu Yang,Feng-Zhi Xin,Xiao-Lin Liu,Qin Pan,Huiping Zhou,Jian-Gao Fan 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

Glucagon-like peptide-1 (GLP-1) has a broad spectrum of biological activity by regulating metabolic processes via both the direct activation of the class B family of G protein-coupled receptors and indirect nonreceptor-mediated pathways. GLP-1 receptor (GLP-1R) agonists have significant therapeutic effects on non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) in animal models. However, clinical studies indicated that GLP-1 treatment had little effect on hepatic steatosis in some NAFLD patients, suggesting that GLP-1 resistance may occur in these patients. It is wellknown that the gut metabolite sodium butyrate (NaB) could promote GLP-1 secretion from intestinal L cells. However, it is unclear whether NaB improves hepatic GLP-1 responsiveness in NAFLD. In the current study, we showed that the serum GLP-1 levels of NAFLD patients were similar to those of normal controls, but hepatic GLP-1R expression was significantly downregulated in NAFLD patients. Similarly, in the NAFLD mouse model, mice fed with a high-fat diet showed reduced hepatic GLP-1R expression, which was reversed by NaB treatment and accompanied by markedly alleviated liver steatosis. In addition, NaB treatment also upregulated the hepatic p-AMPK/p-ACC and insulin receptor/ insulin receptor substrate-1 expression levels. Furthermore, NaB-enhanced GLP-1R expression in HepG2 cells by inhibiting histone deacetylase-2 independent of GPR43/GPR109a. These results indicate that NaB is able to prevent the progression of NAFL to NASH via promoting hepatic GLP-1R expression. NaB is a GLP-1 sensitizer and represents a potential therapeutic adjuvant to prevent NAFL progression to NASH.

Facile Synthesis of Graphene–Enwrapped Ag3PO4 Composites with Highly Efficient Visible Light Photocatalytic Performance

Shi Lei,Da Chen,Wenting Xie,Jing Zhang,Guangxing Ping,Meiqiang Fan,Laishun Qin,Liqun Bai,Zhi Chen,Chunju Lv,Kangying Shu 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.1

In this work, thermally exfoliated graphene nanosheets (GNS) were employed to prepare novel Ag3PO4–GNS composite photocatalysts by a facile chemical precipitation approach. The asprepared Ag3PO4–GNS composite photocatalysts were characterized by X-ray diffraction (XRD) pattern, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Raman spectroscopy, thermogravimetric (TG) analysis, ultraviolet-visible diffuse re-flectance spectroscopy (DRS) and photoluminescence (PL) spectra. It was found that the Ag3PO4 particles were well deposited on the surfaces of GNS. Compared with bare Ag3PO4 and Ag3PO4–rGO composite, the Ag3PO4–GNS composite exhibited enhanced photocatalytic activity for the photodegradation of rhodamine B (RhB) under visible light irradiation. The photocatalytic degradation rate of Ag3PO4–GNS composite was 1.7 times that of bare Ag3PO4 and about 1.3 times that of Ag3PO4–rGO for the degradation of RhB. Furthermore, the photocatalytic stability of Ag3PO4–GNS composite was also greatly enhanced. This enhanced photocatalytic activity and stability could be ascribed to the positive synergetic effects between the Ag3PO4 particles and GNS sheets, which could provide a greater number of active adsorption sites, suppress charge recombination and reduce the serious photocorrosion of Ag3PO4. Moreover, the photocatalytic degradation of RhB over Ag3PO4–GNS composites was also optimized, suggesting that the optimal amount of GNS in the composites was 11.4 wt.%. This work shows a great potential of Ag3PO4–GNS composite for environmental treatment of organic pollutants.

Development of a position sensitive CsI(Tl) crystal array

Shi, Guo-Zhu,Chen, Ruo-Fu,Chen, Kun,Shen, Ai-Hua,Zhang, Xiu-Ling,Chen, Jin-Da,Du, Cheng-Ming,Hu, Zheng-Guo,Fan, Guang-Wei Korean Nuclear Society 2020 Nuclear Engineering and Technology Vol.52 No.4

A position-sensitive CsI(Tl) crystal array coupled with the multi-anode position sensitive photomultiplier tube (PS-PMT), Hamamatsu H8500C, has been developed at the Institute of Modern Physics. An effective, fast, and economical readout circuit based on discretized positioning circuit (DPC) bridge was designed for the 64-channel multi-anode flat panel PSPMT. The horizontal and vertical position resolutions are 0.58 mm and 0.63 mm respectively for the 1.0 × 1.0 × 5.0 ㎣ CsI(Tl) array, and the horizontal and vertical position resolutions are 0.86 mm and 0.80 mm respectively for the 2.0 × 2.0 × 10.0 ㎣ CsI(Tl) array. These results show that the CsI(Tl) crystal array with low cost could be applied in the fields of medical imaging and high-resolution gamma camera.

Cloning, Expression, and Characterization of Endoglucanase Gene egIV from Trichoderma viride AS 3.3711

( Huang Xiao Mei ),( Jin Xia Fan ),( Qian Yang ),( Xiu Ling Chen ),( Zhi Hua Liu ),( Yun Wang ),( Da Qing Wang ) 한국미생물 · 생명공학회 2012 Journal of microbiology and biotechnology Vol.22 No.3

Endoglucanase gene egIV was cloned from Trichoderma viride AS 3.3711, an important cellulose-producing fungus, by using an RT-PCR protocol. The egIV cDNA is 1,297 bp in length and contains a 1,035 bp open reading frame encoding a 344 amino acid protein with an estimated molecular mass of 35.5 kDa and isoelectronic point (pI) of 5.29. The expression of gene egIV in T. viride AS 3.3711 could be induced by sucrose, corn straw, carboxymethylcellulose (CMC), or microcrystalline cellulose, but especially by CMC. The transcripts of egIV were regulated under these substrates, but the expression level of the egIV gene could be inhibited by glucose and fructose. Three recombinant vectors, pYES2-xegIV, pYES2Mα-egIV, and pYES2Mα-xegIV, were constructed to express the egIV gene in Saccharomyces cerevisiae H158. The CMCase activity of yeast transformants IpYES2Mα-xegIV was higher than that of transformant IpYES2-xegIV or IpYES2Mα-egIV, with the highest activity of 0.13 U/ml at induction for 48 h, illustrating that the modified egIV gene could enhance CMCase activity and that MFα signal peptide from S. cerevisiae could regulate exogenous gene expression more effectively in S. cerevisiae. The recombinant EGIV enzyme was stable at pH 3.5 to 7.5 and temperature of 35oC to 65oC. The optimal reaction condition for EGIV enzyme activity was at the temperature of 55oC, pH of 5.0, 0.75 mM Ba2+, and using CMC as substrate. Under these conditions, the highest activity of EGIV enzyme in transformant IpYES2Mα-xegIV was 0.18 U/ml. These properties would provide technical parameters for utilizing cellulose in industrial bioethanol production.

Facile Synthesis of g-C₃N₄ Modified Bi₂MoO₆ Nanocomposite with Improved Photoelectronic Behaviors

Zhu, Lei,Tang, Jia-Yao,Fan, Jia-Yi,Sun, Chen,Meng, Ze-Da,Oh, Won-Chun Materials Research Society of Korea 2021 한국재료학회지 Vol.31 No.11

Herein, a series of g-C₃N₄ modified Bi₂MoO₆ nanocomposites using Bi₂MoO₆ and melamine as original materials are fabricated via sintering process. For presynthesis of Bi₂MoO₆ an ultrasonic-assisted hydrothermal technique is researched. The structure and composition of the nanocomposites are characterized by Raman spectroscopy, X-ray diffraction (XRD), and high-resolution field emission scanning electron microscopy (SEM). The improved photoelectrochemical properties are studied by photocurrent density, EIS, and amperometric i-t curve analysis. It is found that the structure of Bi₂MoO₆ nanoparticles remains intact, with good dispersion status. The as-prepared g-C₃N₄/Bi₂MoO₆ nanocomposites (BMC 5-9) are selected and investigated by SEM analysis, which inhibits special morphology consisting of Bi₂MoO₆ nanoparticles and some g-C₃N₄ nanosheets. The introduction of small sized g-C₃N₄ nanosheets in sample BMC 9 is effective to improve the charge separation and transfer efficiency, resulting in enhancing of the photoelectric behavior of Bi₂MoO₆. The improved photoelectronic behavior of g-C₃N₄/Bi₂MoO₆ may be attributed to enhanced charge separation efficiency, photocurrent stability, and fast electron transport pathways for some energy applications.

An On-Machine and Vision-Based Depth-Error Measurement Method for Micro Machine Tools

Shih-Ming Wang,Han-Jen Yu,Shih-His Liu,Da-Fan Chen 한국정밀공학회 2011 International Journal of Precision Engineering and Vol. No.

The error measurement method is an essential for further enhancing the machining accuracy of a micro machine tool. An on-machine vision-based measurement method that can measure 2-D contouring-/tracking errors of a micro machining process had been previously developed. An on-machine depth-error measurement method was proposed in this study to fulfill the complete 3-D machining errors measurement. The method adopts image re-constructive technology and camera pixel correction to provide non-contact measurement capability. To improve the measurement limits due to the pixel resolution and the filler of view of a CCD, a 2-step measurement method with use of a depth model was developed. Because of the capability of eliminating the shadow effects caused by the tilting light source, the proposed method provides more accurate and reliable measurement results. Sensitivity analysis was conducted to assess the influence of the CCD setup errors on the measurement accuracy for implementation. Experiment was conducted and the results have shown the effectiveness and feasibility of the measurement method.