The power of surface science

Qi-Kun XUE 한국진공학회 2016 한국진공학회 학술발표회초록집 Vol.2016 No.8

Dynamic experimental study on single and double beam-column joints in steel traditional-style buildings

Xue, Jianyang,Qi, Liangjie,Yang, Kun,Wu, Zhanjing Techno-Press 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.63 No.5

In order to study the failure mode and seismic behavior of the interior-joint in steel traditional-style buildings, a single beam-column joint and a double beam-column joint were produced according to the relevant building criterion of ancient architectural buildings and the engineering instances, and the dynamic horizontal loading test was conducted by controlling the displacement of the column top and the peak acceleration of the actuator. The failure process of the specimens was observed, the bearing capacity, ductility, energy dissipation capacity, strength and stiffness degradation of the specimens were analyzed by the load-displacement hysteresis curve and backbone curve. The results show that the beam end plastic hinge area deformed obviously during the loading process, and tearing fracture of the base metal at top and bottom flange of beam occurred. The hysteresis curves of the specimens are both spindle-shaped and plump. The ultimate loads of the single beam-column joint and double beam-column joint are 48.65 kN and 70.60 kN respectively, and the equivalent viscous damping coefficients are more than 0.2 when destroyed, which shows the two specimens have great energy dissipation capacity. In addition, the stiffness, bearing capacity and energy dissipation capacity of the double beam-column joint are significantly better than that of the single beam-column joint. The ductility coefficients of the single beam-column joint and double beam-column joint are 1.81 and 1.92, respectively. The cracks grow fast when subjected to dynamic loading, and the strength and stiffness degradation is also degenerated quickly.

Dynamic experimental study on single and double beam-column joints in steel traditional-style buildings

Jian-yang Xue,Liangjie Qi,Kun Yang,Zhanjing Wu 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.63 No.5

In order to study the failure mode and seismic behavior of the interior-joint in steel traditional-style buildings, a single beam-column joint and a double beam-column joint were produced according to the relevant building criterion of ancient architectural buildings and the engineering instances, and the dynamic horizontal loading test was conducted by controlling the displacement of the column top and the peak acceleration of the actuator. The failure process of the specimens was observed, the bearing capacity, ductility, energy dissipation capacity, strength and stiffness degradation of the specimens were analyzed by the load-displacement hysteresis curve and backbone curve. The results show that the beam end plastic hinge area deformed obviously during the loading process, and tearing fracture of the base metal at top and bottom flange of beam occurred. The hysteresis curves of the specimens are both spindle-shaped and plump. The ultimate loads of the single beam-column joint and double beam-column joint are 48.65 kN and 70.60 kN respectively, and the equivalent viscous damping coefficients are more than 0.2 when destroyed, which shows the two specimens have great energy dissipation capacity. In addition, the stiffness, bearing capacity and energy dissipation capacity of the double beam-column joint are significantly better than that of the single beam-column joint. The ductility coefficients of the single beam-column joint and double beam-column joint are 1.81 and 1.92, respectively. The cracks grow fast when subjected to dynamic loading, and the strength and stiffness degradation is also degenerated quickly.

Protective effect of procyanidin B2 on hydrogen peroxide (H2O2)-induced oxidative damage in MCF-7 cells

Tan Jia-qi,Li Peng-cheng,Li Qian,Tang Jin-tian,Xue Hong-kun 한국응용생명화학회 2020 Applied Biological Chemistry (Appl Biol Chem) Vol.63 No.5

The aim of this study is to assess the cytoprotection and potential molecular mechanisms of procyanidin B2 ( PCB2) on hydrogen peroxide ( H2O2)-induced oxidative damage in MCF-7 cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to determine the viability of MCF-7 cell exposure to H2O2 or PCB2. We measured the antioxidant properties of PCB2 by determining the activities of SOD, GSH-Px, LDH and MDA levels, and evaluated apoptosis and intracellular reactive oxygen species (ROS) levels. The related proteins expression levels were monitored by Western blot. MCF-7 cells induced with H2O2 had a remarkable decrease in cell viability that was suppressed when it was interfered with PCB2 (0.1–10.0 μM). PCB2 interference memorably and dose-dependently inhibited H2O2- induced LDH leakage, ROS and MDA overproduction, while PCB2 markedly increased H2O2- induced the activities of SOD and GSH-Px. Eventually, H2O2 prominently down-regulated the ratio of Bcl-2/Bax and the relative proteins expression levels of Nrf2, GCLC, NQO1 and HO-1, and up-regulated the relative proteins expression levels of cytochrome c, caspase-3 and Keap1. However, the relative expression levels of these proteins were reversed in PCB2- interfered MCF-7 cells. This study implied that protective effect of PCB2 on H2O2- induced oxidative damage in MCF-7 cells might be related to inhibition of mitochondria-dependent apoptosis, activation of Keap1/Nrf2/HO-1 signaling pathway and improvement of the antioxidant enzymes activities.

Impact of Caspase-8 (CASP8) -652 6N Del and D302H Polymorphisms on Prostate Cancer in Different Ethnic Groups

Zhang, Cheng-Dong,Li, Hong-Tao,Liu, Kun,Lin, Zhi-Di,Peng, Qi-Liu,Qin, Xue,He, Min,Wu, Hua,Mo, Zeng-Nan,Yang, Xiao-Li Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

Background: Despite evidence suggesting roles for caspase-8 (CASP8) -652 6N del and D302H polymorphisms in prostate cancer (PCa), the association of these polymorphisms with PCa risk remains inconclusive. Therefore, a meta-analysis was performed to more precisely estimate the association of CASP8 -652 6N del and D302H polymorphisms with PCa susceptibility. Materials and Methods: A comprehensive literature search was conducted to identify all case-control studies of CASP8 D302H and -652 6N del polymorphisms and PCa risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the association and the precision of the estimate, respectively. Results: Nine -625 6N del studies and 4 D302H studies were included. CASP8 -652 6N del and D302H polymorphisms were not significantly associated with PCa risk in the overall analyses. However, in the subgroup analysis stratified by ethnicity, -625 6N del was significantly associated with PCa risk in the East Asian and Indian populations under the recessive model. Furthermore, the subgroup analysis strongly suggested that D302H was associated with lower PCa risk in the Non-Indian population under the dominant model. Conclusions: In our meta-analysis, ethnic-specific differences were evident in the association of CASP8-625 6N del and D302H polymorphisms with PCa risk.

Effects of the Hippo Signaling Pathway in Human Gastric Cancer

Zhou, Guang-Xi,Li, Xiao-Yu,Zhang, Qi,Zhao, Kun,Zhang, Cui-Ping,Xue, Chang-Hu,Yang, Kun,Tian, Zi-Bin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.9

Background/Aim: The Hippo signaling pathway is a newly discovered and conserved signaling cascade, which regulates organ size control by governing cell proliferation and apoptosis. This study aimed to investigate its effects in human gastric cancer. Methods: Tumor tissues (n=60), adjacent non-tumor tissues (n=60) and normal tissues (n=60) were obtained from the same patients with primary gastric cancer (GC). In addition, 70 samples of chronic atrophic gastritis (CAG) tissues were obtained from patients with intestinal metaplasia (IM) by endoscopic biopsy. Hippo signaling molecules, including Mst1, Lats1, YAP1, TAZ, TEAD1, Oct4 and CDX2, were determined by quantitative polymerase chain reaction (qPCR). Protein expression of Mst1, Lats1, YAP1, TEAD1 and CDX2 was assessed by immunohistochemistry and Western blotting. Results: Mst1, Lats1 and Oct4 mRNA expression showed an increasing tendency from GC tissues to normal gastric tissues, while the mRNA expression of YAP1, TAZ and TEAD1 was up-regulated (all P<0.01). Mst1 and Lats1 protein expression presented a similar trend with their mRNA expression. In addition, YAP1 and TEAD1 protein expression in GC was significantly higher than in the other groups (all P<0.01). CDX2 mRNA and protein expression in the CAG group were higher than in the other groups (all P<0.01). In GC, mRNA expression of Mst1, Lats1, Oct4, YAP1, TAZ, TEAD1 and CDX2 had a close correlation with lymphatic metastasis and tumor TNM stage (all P<0.01). Furthermore, protein expression of Mst1, Lats1, YAP1, TAZ, TEAD1 and CDX2 had a close correlation between each other (P<0.05). Conclusion: The Hippo signaling pathway is involved in the development, progression and metastasis of human gastric cancer. Therefore, manipulation of Hippo signaling molecules may be a potential therapeutic strategy for gastric cancer.

C57BL/6 생쥐에서 전해알칼리환원수가 호르텐스극구흡충 감염과 면역에 미치는 영향

김동희,등영건,김단,황학수,최주봉,김광용,이규재,Kim, Dong-Heui,Deung, Young-Kun,Jin, Dan,Huang, Xue Zhu,Qi, Xu Feng,Kim, Kwang-Yong,Lee, Kyu-Jae 한국현미경학회 2008 Applied microscopy Vol.38 No.1

전해알칼리환원수가 동물의 면역에 미치는 영향을 알아보고자 본 실험을 수행하였다. 소장에서 기생하는 호르텐스극구흡충(Echinostoma hortense)을 이용하여 C57BL/6 생쥐 소장과 혈액에서의 면역반응을 관찰하였다. C57BL/6 생쥐에 호르텐스극구흡충 피낭유충을 마리 당 15개 경구감염 시킨 후 2주 경과하여 충체를 회수하였고 소장 점막의 배상세포와 비만세포의 변화를 관찰하였으며 protein chip을 이용하여 혈청 내 cytokine의 변화를 비교 확인하였다. 그 결과 호르텐스극구흡충을 감염시킨 군에서는 평균 8.3마리, 알칼리환원 수를 급이한 군에서는 평균 10마리의 충체를 회수하였다. 배상 세포 변화의 관찰에서는 호르텐스극구흡충을 감염시키고 전해알칼리환원수를 급이한 실험군이 융모 당 평균 4.3개 관찰되어 배상세포의 발현이 적은 것으로(p<0.001) 나타났다. 비만세포 변화의 관찰에서도 호르텐스극구흡충을 감염시키고 전해알칼리환원수를 급이한 실험군에서 응모 당 평균 11개 관찰되었고 정수물을 급이한 호르텐스 감염 대조군에 비해 적게 나타났다(p<0.001). 마우스 혈청 내에서의 cytokine 발현에서 호르텐스극구흡충에 감염된 실험군과 대조군의 비교에서 Th1 cytokine인 IL-6, IL-$1{\beta}$, IFN-${\gamma}$, TNF-${\alpha}$, Il-2 등과 Th2 cytokine인 IL-4, IL-5, IL-10, IL-13 등의 발현은 모두 유의한 차이가 관찰되지 않았다. 본 연구에서 전기분해 알칼리환원수가 호르텐스극구흡충의 감염에 있어 C57BL/6 마우스에서 장점막조직의 배상세포 수 및 mucin terminal sugar의 변화를 억제하고 아울러 이로 인해 충체배출이 지연되며, 알칼리환원수가 호르텐스극구흡충에 감염된 C57BL/6 마우스에서 혈청 내 cytokine의 변화에는 큰 영향을 미치지 않는다는 결론을 얻었다. To examine the effect of the electrolyzed alkaline reduced water (ERW) on animal immunity, by employing Echinostoma hortense that is a parasite in the small intestine, the immune response of C57BL/6 was examined. To C57BL/6 mice, Echinostoma hortense metacercaria 15 per animal was in oculate dorsally, the worm was collected after 2 weeks, and the change of goblet cells and mast cells in the mucosa of small intestine was examined, and by using a protein chip, the change of cytokines in the serum was compared and observed. As a result, average 8.3 worms were collected from the C57BL/6 mice infected with E. hortense, and in the group fed with the ERW, average 10 worms were collected. In regard to the examination of the change of goblet cells, in the experimental group infected with E. hortense and fed with the ERW, average 4.3 worms per villus were detected, hence, it was found that the expression of goblet cells was low (p<0.001). Regarding the examination of the change of mast cells, similarly, in the group infected with E. hortense and fed with the ERW, average 11 worms per villus were detected, and it appears to be less than control group (p<0.001). Regarding the expression of cytokines in mouse serum, in comparison of the experiment group infected with E. hortense and control group, in the expression of the Th1 cytokines IL-6, IL-$1{\beta}$, IFN-${\gamma}$, TNF-${\alpha}$, and IL-2, and the Th2 cytokines IL-4, IL-5, IL-10, and IL-13, a significant difference was not detected. In our study, it was found that in the infection of E. hortense, the ERW mediates its effect on the number of goblet cells and mast cells in the intestinal mucosa, and simultaneously, the worm expulsion was delayed, and thus the conclusion that the ERW mediated its effect on the intestinal immunity of mice was obtained.

Initial Adsorption and Kondo Resonance of 5,10,15,20-Tetrakis(4-bromophenyl)porphyrin-Co Molecules on Ag/Si(111) Surface Studied by Low-Temperature Scanning Tunneling Microscopy/Spectroscopy

Li, Qing,Yamazaki, Shiro,Eguchi, Toyoaki,Kim, Howon,Kahng, Se-Jong,Jia, Jing-Feng,Xue, Qi-Kun,Hasegawa, Yukio IOP Publishing 2009 Japanese journal of applied physics Vol.48 No.8