Evolutionary dynamics of transposable elements during silkworm domestication

Min‑Jin Han,Hong‑En Xu,Xiao‑Min Xiong,Hua‑Hao Zhang 한국유전학회 2018 Genes & Genomics Vol.40 No.10

Although there are some documented examples on population dynamics of transposable elements (TEs) in model organisms, the evolutionary dynamics of TEs in domesticated species has not been systematically investigated. The objective of this study is to understand population dynamics of TEs during silkworm domestication. In this work, using transposondisplay we examined the polymorphism of seven TE families [they represent about 59% of silkworm (Bombyx mori) total TE content] in four domesticated silkworm populations and one wild silkworm population. Maximum likelihood (ML) was used to estimate selection pressure. Population differentiation and structure were performed by using AMOVA analysis and program DISTRUCT, respectively. The results of transposon-display showed that significant differentiation occurred between the domesticated silkworm and wild silkworm. These TEs have experienced expansions and fixation in the domesticated silkworm but not in wild silkworm. Furthermore, the ML results indicated that purifying selection of TEs in the domesticated silkworm were significantly weaker than that in the wild silkworm. Interestingly, an adaptation insertion induced by BmMITE-2 was found, and this insertion can reduce the polymorphism of the flanking regions of its neighboring COQ7 gene. Our results suggested that TEs expanded and were fixed in the domesticated silkworm might result from demographic effects and artificial selection during domestication. We concluded that the data presented in this study have general implication in animal and crop improvements as well as in domestication of new species.

The Effect of Perceived Service Quality on Brand Loyalty in Hotels: The Causal Role of Relationship Quality and the Mediating Effect of Employee Trust

Jialei Xu(Jialei Xu),Chul-Jae Choi(Chul-Jae Choi),Dae-Gyu Min(Dae-Gyu Min) The International Academy of Global Business and T 2023 The International Academy of Global Business and T Vol.19 No.3

Purpose - As the spread of COVID-19 has weakened recently, countries have switched to ‘with Corona’ policies. The hotel service industry, which has been hit hard in sales, is also making every effort to overcome difficulties through various brand strategies to provide high-quality services to customers and strengthen relationship quality through the trust of service employees at service points. Therefore, this study aims to verify the mediating role of employee trust in the relationship between perceived service quality and brand satisfaction and brand trust, and the causal effect of brand commitment by verifying whether brand satisfaction and brand trust affect brand loyalty or through brand commitment. Design/Methodology/Approach - Data were collected from consumers with experience using upscale hotels in Korea, and the research hypotheses were verified by structural equation model analysis using the SPSS 21.0 and Amos 21.0 statistical packages. Findings - First, the mediating effect of employee trust was confirmed in the relationship between perceived service quality, brand satisfaction, and brand trust. Second, brand satisfaction influenced brand trust and brand commitment, and brand trust influenced brand commitment. Third, brand satisfaction did not directly affect brand loyalty, but it did affect brand trust and brand commitment, and these constructs affected brand loyalty. Research Implications - In conclusion, it is necessary to manage service training for employees, as interactions with customers at the service point can provide the correct service and strengthen brand loyalty by identifying each component of brand relationship quality and checking the influence in the channel relationship.

VEGFR2 Expression in Head and Neck Squamous Cell Carcinoma Cancer Cells Mediates Proliferation and Invasion

Xu, Hui-Min,Zhu, Jian-Guo,Gu, Lian,Hu, Song-Qun,Wu, Hao Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.4

Vascular endothelial growth factor 2 (VEGFR2) was initially identified as a receptor of VEGF on endothelial cells with a role in regulating angiogenesis during organism development and tumorigenesis. Previously, in cancer tissue, VEGFR2 has been reported to be expressed in endothelial cells. In our research, we found that VEGFR2 was expressed not only in endothelial cells but also cancer cells in head and neck squamous cell carcinomas (HNSCCs). Knockdown of VEGFR2 in Hep2 cells could arrest the cell cycle in G0/G1, leading to a decrease in proliferation. We also present evidence that MAPK/ERK signal pathways and expression of CDK1 downstream of VEGFR2 might regulate proliferation and cell cycle arrest. Furthermore, we discovered that down-regulate VEGRF2 in Hep2 cells could significantly affect the invasion ability. Taken together, our data suggest that VEGFR2 might regulate proliferation and invasion in HNSCC cancer cells in vivo.

Continuous fermentative butyric acid and acetic acid production from Laminaria japonica using a two-stage fermentation system

XU XU,Ji-Young KIM,Min-Woo LEE,Jong-Moon PARK 한국생물공학회 2013 한국생물공학회 학술대회 Vol.2013 No.4

ORiginal Article : Pyrrolidine Dithiocarbamate Inhibits Nuclear Factor κB and Toll-Like Receptor 4 Expression in Rats with Acute Necrotizing Pancreatitis

( Min Xu ),( Kun Ning Wang ),( Kai Wu ),( Xing Peng Wang ) The Editorial Office of Gut and Liver 2015 Gut and Liver Vol.9 No.3

Background/Aims: To investigate the expression of Tolllike receptor 4 (TLR4) in the pancreases of rats with acute necrotizing pancreatitis (ANP) and any changes upon treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor κB (NF-κB), as well as to determine the relationship between TLR4 and NF-κB in ANP pathogenesis. Methods: A total of 72 SD rats were randomly divided into three groups, namely, the control (sham-operation), ANP, and ANP with PDTC pretreatment groups. The PDTC-pretreated group was intraperitoneally injected with PDTC at a dose of 100 mg/kg 1 hour before the induction of ANP. The expressions of TLR4 and NF-κB in pancreatic tissue were evaluated by immunohistochemistry and Western blot analysis. The mRNA levels of cytokines tumor necrosis factor α, interleukin (IL)-1β, and IL-6 were measured by reverse transcription polymerase chain reaction. Results: The expressions of TLR4, NF-κB, and cytokine (NF-κB target) genes in the pancreatic tissue increased more significantly in the ANP groups than in the sham-operation group at 3, 6, and 12 hours. Pretreatment with PDTC alleviated the inflammatory activation in the pancreas with ANP, causing a significant decrease in the expressions of TLR4, NF-κB, and cytokine genes in the pancreatic tissue. Conclusions: The expressions of TLR4 and NF- κB were increased in the pancreases of rats with ANP. PDTC not only inhibits NF-κB but also suppresses the expression of TLR4 and downregulates the expression of the related cytokine genes. (Gut Liver 2015;9:411-416)

A Harmonic Detection Method for Distributed Generation Connected Grid System Using DWT and HHT

Min Xu,Tianhong Pan,Jiao Chen,Zhengming Li 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.4

In distributed generation (DG) connected grid system, there is serious harmonic pollution caused by the wide use of inverter units and nonlinear loads. The traditional detection methods (such as Fast Fourier Transform and wavelet analysis) heavily depend on synchronous signal detection or basis functions selection, which don’t satisfy the requirements of the harmonic detection of the micro-grid environment. Therefore, a novel method combining discrete wavelet transform (DWT) with Hilbert–Huang transform (HHT) is proposed to detect and analyze the harmonic. The method uses multi resolution analysis of DWT to process the original signal. Then, a series of intrinsic mode function (IMF) components are obtained from the processed signal by using Empirical Mode Decomposition (EMD) algorithm. Thirdly, the fundamental component and harmonic are extracted from the IMF components. Finally, the frequency and amplitude of the signal are calculated by using the HHT. Simulation results demonstrate that the proposed algorithm has high precision and good real-time characteristics. Furthermore, the proposed algorithm satisfi es the requirements of the harmonic detection of the DG connected grid system.

N-doped graphene field-effect transistors with enhanced electron mobility and air-stability.

Xu, Wentao,Lim, Tae-Seok,Seo, Hong-Kyu,Min, Sung-Yong,Cho, Himchan,Park, Min-Ho,Kim, Young-Hoon,Lee, Tae-Woo Wiley-VCH 2014 Small Vol.10 No.10

<P>Although graphene can be easily p-doped by various adsorbates, developing stable n-doped graphene that is very useful for practical device applications is a difficult challenge. We investigated the doping effect of solution-processed (4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl)dimethylamine (N-DMBI) on chemical-vapor-deposited (CVD) graphene. Strong n-type doping is confirmed by Raman spectroscopy and the electrical transport characteristics of graphene field-effect transistors. The strong n-type doping effect shifts the Dirac point to around -140 V. Appropriate annealing at a low temperature of 80 oC enables an enhanced electron mobility of 1150 cm(2) V(-1) s(-1). The work function and its uniformity on a large scale (1.2 mm 1.2 mm) of the doped surface are evaluated using ultraviolet photoelectron spectroscopy and Kelvin probe mapping. Stable electrical properties are observed in a device aged in air for more than one month.</P>

Silicon Dioxide Particles Deposited in Vessels and Cartilage of the Femoral Head

Min Xu,Dan Peng,Meiying Qing 연세대학교의과대학 2014 Yonsei medical journal Vol.55 No.5

Silicosis had been considered for decades as an illness with manifestations of lung fibrosis due to inhalation of overconcentrated SiO2 dust. To the best of our knowledge,studies have yet to report SiO2 deposits in any other tissues and organs. In the present case, while performing bilateral artificial total hip arthroplasty for one patient, we found that the articular cartilage of the bilateral femoral head was black. Therefore, specimens thereof were sent for pathological examination. Pathologicalexamination (immunohistochemistry) and polarized light microscopy revealedthe presence of considerable brown, acicular, rhombic, and crumb-like crystals. The crystals were mainly composed of SiO2. SiO2 could deposit in vessels and femoral head cartilage via blood circulation.

Sulfur–Graphene Nanostructured Cathodes <i>via</i> Ball-Milling for High-Performance Lithium–Sulfur Batteries

Xu, Jiantie,Shui, Jianglan,Wang, Jianli,Wang, Min,Liu, Hua-Kun,Dou, Shi Xue,Jeon, In-Yup,Seo, Jeong-Min,Baek, Jong-Beom,Dai, Liming American Chemical Society 2014 ACS NANO Vol.8 No.10

<P>Although much progress has been made to develop high-performance lithium–sulfur batteries (LSBs), the reported physical or chemical routes to sulfur cathode materials are often multistep/complex and even involve environmentally hazardous reagents, and hence are infeasible for mass production. Here, we report a simple ball-milling technique to combine both the physical and chemical routes into a one-step process for low-cost, scalable, and eco-friendly production of graphene nanoplatelets (GnPs) edge-functionalized with sulfur (S-GnPs) as highly efficient LSB cathode materials of practical significance. LSBs based on the S-GnP cathode materials, produced by ball-milling 70 wt % sulfur and 30 wt % graphite, delivered a high initial reversible capacity of 1265.3 mAh g<SUP>–1</SUP> at 0.1 C in the voltage range of 1.5–3.0 V with an excellent rate capability, followed by a high reversible capacity of 966.1 mAh g<SUP>–1</SUP> at 2 C with a low capacity decay rate of 0.099% per cycle over 500 cycles, outperformed the current state-of-the-art cathode materials for LSBs. The observed excellent electrochemical performance can be attributed to a 3D “sandwich-like” structure of S-GnPs with an enhanced ionic conductivity and lithium insertion/extraction capacity during the discharge–charge process. Furthermore, a low-cost porous carbon paper pyrolyzed from common filter paper was inserted between the 0.7S-0.3GnP electrode and porous polypropylene film separator to reduce/eliminate the dissolution of physically adsorbed polysulfide into the electrolyte and subsequent cross-deposition on the anode, leading to further improved capacity and cycling stability.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2014/ancac3.2014.8.issue-10/nn5047585/production/images/medium/nn-2014-047585_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn5047585'>ACS Electronic Supporting Info</A></P>

Tanshinone IIA Reverses the Malignant Phenotype of SGC7901 Gastric Cancer Cells

Xu, Min,Cao, Fa-Le,Li, Nai-Yi,Liu, Yong-Qiang,Li, Yan-Peng,Lv, Chun-Lei Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Backgrounds: Tanshinone IIA (TIIA), a phenanthrenequinone derivative extracted from Salvia miltiorrhiza BUNGE, has been reported to be a natural anti-cancer agent in a variety of tumor cells. However, the effect of TIIA on gastric cancer cells remains unknown. In the present study, we investigated the influence of TIIA on the malignant phenotype of SGC7901 gastric cancer cells. Methods: Cells cultured in vitro were treated with TIIA (0, 1, 5, $10{\mu}g/ml$) and after incubation for different periods, cell proliferation was measured by MTT method and cell apoptosis and cell cycling were assessed by flow cytometry (FCM). The sensitivity of SGC7901 gastric cancer cells to anticancer chemotherapy was investigated with the MTT method, while cell migration and invasion were examined by wound-healing and transwell assays, respectively. Results: TIIA (1, 5, $10{\mu}g/ml$) exerted powerful inhibitory effects on cell proliferation (P < 0.05, and P < 0.01), and this effect was time- and dose-dependent. FCM results showed that TIIA induced apoptosis of SGC7901 cells, reduced the number of cells in S phase and increased those in G0/G1 phase. TIIA also significantly increased the sensitivity of SGC7901 gastric cancer cells to ADR and Fu. Moreover, wound-healing and transwell assays showed that TIIA markedly decreased migratory and invasive abilities of SGC7901 cells. Conclusions: TIIA can reverse the malignant phenotype of SGC7901 gastric cancer cells, indicating that it may be a promising therapeutic agent.