DNA methylation and mRNA expression of COL6A3 in antler mesenchyme of female and male reindeer

Jian‑Cheng Zhai,Ruo‑Bing Han,Sheng‑Nan Wang,Qiang‑Hui Wang,Yan‑Ling Xia,Wei‑Shi Liu,Ya‑Jie Yin,He‑Ping Li 한국유전학회 2019 Genes & Genomics Vol.41 No.9

Backgroud Reindeer is the only deer species that both male and female produce antlers, which provides a particularly interesting case in studying the differences between antlers of the two sexes. Alpha 3(VI) Collagen Gene (COL6A3), forms a microfibrillar network associated with the structural integrity and biomechanical properties, has been found to be one of the differentially expressed genes in antler mesenchyme of female and male reindeer. Objective and Methods The promoter sequence of reindeer COL6A3 gene was obtained using the cloning technology and analyzed by the bioinformatics methods. Bisulfite sequencing PCR (BSP) was used to detect the methylation status of the COL6A3 promoter in reindeer antler mesenchyme. Real-time quantitative PCR was used to detect COL6A3 expression in the antler mesenchyme of female and male reindeer. Results Sequence analysis revealed that the reindeer COL6A3 partial promoter sequence was 983 bp including the possible promoter region at + 105 bp to + 155 bp. Homology and phylogenetic analysis indicated that the COL6A3 promoter of reindeer had the closest genetic distance with Bos taurus, Capra hircus and Ovis aries. BSP results indicated that the methylation level of COL6A3 promoter in the female reindeer antler mesenchyme was significantly higher than in the male. Correlating with increased methylation status, we also found that COL6A3 mRNA expression in female reindeer antler mesenchyme was significantly lower than in the male. Conclusion The higher methylation level of the COL6A3 gene in female reindeer antler mesenchyme coincides with decreased COL6A3 mRNA expression, thereby affecting the transposon silencing mechanism and possibly contributing to apparent differences of antlers in female and male reindeer.

Anti-HIV-1 Activity of Lignans from the Fruits of Schisandra rubriflora

Wei-Lie Xiao,Rui-Rui Wang,Wei Zhao,Ren-Rong Tian,Shan-Zhai Shang,Liu-Meng Yang,Jian-Hong Yang,Jian-Xin Pu,Yong-Tang Zheng,Han-Dong Sun 대한약학회 2010 Archives of Pharmacal Research Vol.33 No.5

This study investigated the 70% aqueous acetone extract of the fruits of Schisandra rubriflora which led to the isolation of eight lignans, including a new isolate, rubrisandrin C (1), and seven known lignans (2-8) . The structure of 1 was established by extensive 1D and 2D NMR spectroscopy and its absolute stereochemistry was determined by CD spectrum. Compounds 1-5 and 7-8 were evaluated for their anti-HIV-1 activity that showed inhibitory activity on HIV-1IIIB induced syncytium formation with EC50 values in the range of 2.26~20.4 μg/mL. Compounds 1 and 7 exerted their obvious protection of HIV-1IIIB inducted MT-4 host cells lytic effects with a selectivity index of 15.4 and 24.6, respectively.

5-Aza-2'-deoxycytidine Induces Hepatoma Cell Apoptosis via Enhancing Methionine Adenosyltransferase 1A Expression and Inducing S-Adenosylmethionine Production

Liu, Wei-Jun,Ren, Jian-Guo,Li, Ting,Yu, Guo-Zheng,Zhang, Jin,Li, Chang-Sheng,Liu, Zhi-Su,Liu, Quan-Yan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

In hepatocellular cancer (HCC), lack of response to chemotherapy and radiation treatment can be caused by a loss of epigenetic modifications of cancer cells. Methionine adenosyltransferase 1A is inactivated in HCC and may be stimulated by an epigenetic change involving promoter hypermethylation. Therefore, drugs releasing epigenetic repression have been proposed to reverse this process. We studied the effect of the demethylating reagent 5-aza-2'-deoxycitidine (5-Aza-CdR) on MAT1A gene expression, DNA methylation and S-adenosylmethionine (SAMe) production in the HCC cell line Huh7. We found that MAT1A mRNA and protein expression were activated in Huh7 cells with the treatment of 5-Aza-CdR; the status of promoter hypermethylation was reversed. At the same time, MAT2A mRNA and protein expression was significantly reduced in Huh7 cells treated with 5-Aza-CdR, while SAMe production was significantly induced. However, 5-Aza-CdR showed no effects on MAT2A methylation. Furthermore, 5-Aza-CdR inhibited the growth of Huh7 cells and induced apoptosis and through down-regulation of Bcl-2, up-regulation of Bax and caspase-3. Our observations suggest that 5-Aza-CdR exerts its anti-tumor effects in Huh7 cells through an epigenetic change involving increased expression of the methionine adenosyltransferase 1A gene and induction of S-adenosylmethionine production.

Effect of metallic precursors on the thin film thickness and reaction resistances in the selenization process

Wei Liu,Jian-Guo Tian,Qing He,Feng-Yan Li,Chang-Jian Li,Yun Sun 한국물리학회 2011 Current Applied Physics Vol.11 No.3

In the selenization process, the sputtered metallic precursors transformed into CIGS thin films, which were investigated by novel in-situ resistance measurement. Simultaneously, the crystal phases and thicknesses of the selenized thin films at various selenization temperatures are obtained by XRD and XRF,respectively. According to the analysis of phase evolutions and reaction characteristics, it can be confirmed metallic In existed in the precursors will transform into the In―Se compound directly and then results in CIS formation as well as the thickness increase below 370 ℃. Otherwise, if alloy phases Cu ―In and Cu―Ga co-exist in the precursors, not CIS but CIGS will form above 470°, which will lead to both thickness and resistance increase in the corresponding temperature range. Consequently, it can be concluded the thickness increase are decided by the formation of CIS or CIGS, whereas the strong reaction peak in the temperature-resistance curves are caused only by stoichiometric CIGS.

Study on Absorption Characteristics of Electromagnetic Wave in Thin Plasma Slab

Jian-Xiao Liu,Liu Yu-Jie,Yang Hong-Wei 한국항공우주학회 2023 International Journal of Aeronautical and Space Sc Vol.24 No.3

The absorption characteristics of thin plasma slab are investigated by analyzing isotropy plasma with different thicknesses. When the width of the plasma slab is sufficiently thin, the electromagnetic wave can be transmitted, even if the incidence frequency is low, because of the tunneling effect. The influence of incident wave frequency and incident angle on the absorptivity of electromagnetic wave about tunneling effect is discussed in this paper. Generally, an absorption band created by non-magnetized plasma can be found in the tunneling frequency band (0≤Ω≤1), and the peak frequency is the same as that of the plasma frequency, that is, Ω=1. When the thickness of plasma slab is decreased, another absorption band is gradually generated at Ω=0. It is demonstrated that the absorption band at Ω=0 is in parallel with the absorption band at Ω=1. The absorption characteristics of electromagnetic wave in tunneling frequency band are quite different from those of non-magnetized plasma because magnetized plasma is anisotropic medium. Two absorption bands are formed in right-handed circularly polarized wave (RCP wave), which are cyclotron resonance absorption band and collision absorption band. The two absorption bands are bent due to the cyclotron frequency and incident angle. However, only one collision absorption band can be found in left-handed circularly polarized wave (LCP wave). The distribution regulars of absorption bands formed by the two polarization modes in the range of 0≤Ωb≤2 and 0∘≤θ≤90∘ are researched. The collision absorption bands of LCP wave and RCP wave are found to be reciprocal in the range we studied. The distribution maps of the absorption band as functions of Ωb and θ are achieved by curve fitting. The reciprocal characteristic of collision absorption bands of LCP wave and RCP wave is verified. A method for measuring density of magnetized plasma is proposed based on the reciprocal relationship found in this paper.

Tunable optical bistability at microwave frequency based on 1D sandwich photonic structure consisting of a nonlinear dielectric slab and two magnetized cold plasma layers

Liu Wei,Wu Jian-Wei 한국물리학회 2021 Current Applied Physics Vol.29 No.-

In this paper, tunable optical bistability that denotes the relationship between input intensity and output intensity is numerically investigated in the microwave frequency region based on the one-dimensional (1D) sandwich photonic structure consisting of a Kerr-type nonlinear material slab and two magnetized cold plasma layers. Results show that, in the case of TM-polarized electromagnetic wave, width and switching thresholds of the bistability loops are dependent on the working frequency, initial incidence angle, layer thickness, plasma density, and external magnetic field, which should be judiciously selected to obtain a required bistability behavior. Compared to the case of switch-down threshold, the switch-up threshold in the bistability loop is more sensitive to the changes of parameters. Through this study, the suggested 1D sandwich photonic structure is beneficial to the all-optical signal processing.

Silencing of Lysyl Oxidase Gene Expression by RNA Interference Suppresses Metastasis of Breast Cancer

Liu, Jian-Lun,Wei, Wei,Tang, Wei,Jiang, Yi,Yang, Hua-Wei,Li, Jing-Tao,Zhou, Xiao Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.7

Objective: The aim of this study was to investigate possible mechanisms of LOX gene effects on invasion and metastasis of breast cancer cells by RNA interference. Methods: LOX-RNAi-LV was designed, synthesized, and then transfected into a breast cancer cell line (MDA-MB-231). Expression of LOX, MMP-2 and MMP-9 was determined by real-time PCR, and protein expression of LOX by Western blotting. Cell migration and invasiveness were assessed with Transwell chambers. A total of 111 cases of breast cancer tissues, cancer-adjacent normal breast tissues, and 20 cases of benign lesion tissues were assessed by immunohistochemistry. Results: Expression of LOX mRNA and protein was suppressed, and the expression of MMP-2 and MMP-9 was significantly lower in the RNAi group than the control group (P<0.05), after LOX-RNAi-LV was transfection into MDA-MB-231 cells. Migration and invasion abilities were obviously inhibited. The expression of LOX protein in breast cancer, cancer-adjacent normal breast tissues and benign breast tumor were 48.6% (54/111), 26.1% (29/111), 20.0% (4/20), respectively, associations being noted with clinical stage, lymph node metastasis, tumor size and ER, PR, HER2, but not age. LOX protein was positively correlated with MMP-2 and MMP-9. Conclusion: LOX displayed an important role in invasion and metastasis of breast cancer by regulating MMP-2 and MMP-9 expression which probably exerted synergistic effects on the extracellular matrix (ECM).

Eliminating the Third Harmonic Effect for Six Phase Permanent Magnet Synchronous Generators in One Phase Open Mode

Jian Liu,Gui-jie Yang,Yong Li,Hong-wei Gao,Jian-yong Su 전력전자학회 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.1

To insure stable operation and eliminate twice torque ripple, a topology for a six phase permanent magnet synchronous generator (SP-PMSG) with a neutral point connected together was analyzed in this paper. By adopting an extended transformation matrix, the mathematic model of the space vector control was established. The voltage and torque equations were deduced while considering the third harmonic flux and inductance. In addition, the suppression third harmonic method and the closed loop control strategy were proposed. A comparison analysis indicates that the cooper loss minimum method and the current magnitude minimum method can meet different application requirements. The voltage compensation amount for each of the methods was deduced which also takes into account the third harmonic effect. A simulation and experimental result comparison validates the consistency through theoretical derivation. It can be seen that all of the two control strategies can meet the requirements of post-fault.

Applicability research of round tube CHF mechanistic model in rod bundle channel

Liu, Wei,Peng, Shinian,Shan, Jianqiang,Jiang, Guangming,Liu, Yu,Deng, Jian,Hu, Ying Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.2

In view of the complex geometric structure of the rod bundle channel and the limitation of the current CHF visualization experiment technology, it is very difficult to obtain the rod bundle CHF mechanism directly through the phenomenon of the rod bundle CHF visualization experiment. In order to obtain the applicable CHF mechanism assumption for rod bundle channel, firstly, five most representative DNB type round tube CHF mechanistic models are obtained with evaluation and screening. Then these original round tube CHF mechanistic models based on inlet conditions are converted to local conditions and coupled with subchannel analysis code ATHAS. Based on 5 × 5 full-length rod bundle CHF experimental data independently developed by Nuclear Power Institute of China (NPIC), the applicability research of each model for CHF prediction performance in rod bundle channel is carried out, and the commonness and difference of each model are comparatively studied. The CHF mechanism assumption of superheated liquid layer depletion that is most likely to be applicable for the rod bundle channel is selected and two directions that need to be improved are given. This study provides a reference for the development of CHF mechanistic model in rod bundle channel.

Eliminating the Third Harmonic Effect for Six Phase Permanent Magnet Synchronous Generators in One Phase Open Mode

Liu, Jian,Yang, Gui-Jie,Li, Yong,Gao, Hong-Wei,Su, Jian-Yong The Korean Institute of Power Electronics 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.1

To insure stable operation and eliminate twice torque ripple, a topology for a six phase permanent magnet synchronous generator (SP-PMSG) with a neutral point connected together was analyzed in this paper. By adopting an extended transformation matrix, the mathematic model of the space vector control was established. The voltage and torque equations were deduced while considering the third harmonic flux and inductance. In addition, the suppression third harmonic method and the closed loop control strategy were proposed. A comparison analysis indicates that the cooper loss minimum method and the current magnitude minimum method can meet different application requirements. The voltage compensation amount for each of the methods was deduced which also takes into account the third harmonic effect. A simulation and experimental result comparison validates the consistency through theoretical derivation. It can be seen that all of the two control strategies can meet the requirements of post-fault.