Hypermethylation-mediated silencing of NDRG4 promotes pancreatic ductal adenocarcinoma by regulating mitochondrial function

( Hao-hong Shi ),( Hai-e Liu ),( Xing-jing Luo ) 생화학분자생물학회(구 한국생화학분자생물학회) 2020 BMB Reports Vol.53 No.12

The N-myc downstream regulated gene (NDRG) family members are dysregulated in several tumors. Functionally, NDRGs play an important role in the malignant progression of cancer cells. However, little is known about the potential implications of NDRG4 in pancreatic ductal adenocarcinoma (PDAC). The aim of the current study was to elucidate the expression pattern of NDRG4 in PDAC and evaluate its potential cellular biological effects. Here, we firstly report that epigenetic-mediated silencing of NDRG4 promotes PDAC by regulating mitochondrial function. Data mining demonstrated that NDRG4 was significantly down-regulated in PDAC tissues and cells. PDAC patients with low NDRG4 expression showed poor prognosis. Epigenetic regulation by DNA methylation was closely associated with NDRG4 down-regulation. NDRG4 overexpression dramatically suppressed PDAC cell growth and metastasis. Further functional analysis demonstrated that up-regulated NDRG4 in SW1990 and Canpan1 cells resulted in attenuated mitochondrial function, including reduced ATP production, decreased mitochondrial membrane potential, and increased fragmented mitochondria. However, opposite results were obtained for HPNE cells with NDRG4 knockdown. These results indicate that hypermethylation-driven silencing of NDRG4 can promote PDAC by regulating mitochondrial function and that NDRG4 could be as a potential biomarker for PDAC patients. [BMB Reports 2020; 53(12): 658-663]

CD64 Expression Is Increased in Patients with Severe Acute Pancreatitis: Clinical Significance

( Hao Zhang ),( Xian Long Ling ),( Yu Yun Wu ),( Mu Han Lu ),( Hong Guo ),( Peng Bin Zhang ),( Xiao Yan Zhao ),( Shi Ming Yang ) 대한소화기학회 2014 Gut and Liver Vol.8 No.4

Background/Aims: Upregulated CD64 expression on neutrophils is the most useful marker for acute bacterial infections and systemic inflammation. However, it is unknown whether CD64 is involved in the pathogenesis of acute pancreatitis (AP). This study was designed to determine whether CD64 is implicated in severe acute pancreatitis (SAP), and thus, is a suitable marker for SAP. Methods: SAP was induced in rats with an intraperitoneal injection of L-arginine. CD64 expression in the rat pancreas was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. Additionally, the CD64 mRNA expression in peripheral blood leukocytes from 21 patients with mild acute pancreatitis (MAP) and 10 patients with SAP was investigated at the time of admission and during remission by qRT-PCR. Results: CD64 mRNA and protein expression in the pancreas was significantly higher in rats with SAP, compared to the controls. The CD64 expression was higher in the patients with SAP than in the patients with MAP. During remission, CD64 mRNA decreased in both the MAP and SAP patients. The area under the curve of CD64 expression for the detection of SAP was superior to both the Ranson and the Acute Physiology and Chronic Health Evaluation II scores. Conclusions: The CD64 level was significantly increased in correlation with the disease severity in SAP and may act as a useful marker for predicting the development of SAP. (Gut Liver 2014;8:445-451)

Bond slip modelling and its effect on numerical analysis of blast-induced responses of RC columns

Shi, Yanchao,Li, Zhong-Xian,Hao, Hong Techno-Press 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.32 No.2

Reinforced concrete (RC) structures consist of two different materials: concrete and steel bar. The stress transfer behaviour between the two materials through bond plays an important role in the load-carrying capacity of RC structures, especially when they subject to lateral load such as blast and seismic load. Therefore, bond and slip between concrete and reinforcement bar will affect the response of RC structures under such loads. However, in most numerical analyses of blast-induced structural responses, the perfect bond between concrete and steel bar is often assumed. The main reason is that it is very difficult to model bond slip in the commercial finite element software, especially in hydrodynamic codes. In the present study, a one-dimensional slide line contact model in LS-DYNA for modeling sliding of rebar along a string of concrete nodes is creatively used to model the bond slip between concrete and steel bars in RC structures. In order to model the bond slip accurately, a new approach to define the parameters of the one-dimensional slide line model from common pullout test data is proposed. Reliability and accuracy of the proposed approach and the one-dimensional slide line in modelling the bond slip between concrete and steel bar are demonstrated through comparison of numerical results and experimental data. A case study is then carried out to investigate the bond slip effect on numerical analysis of blast-induced responses of a RC column. Parametric studies are also conducted to investigate the effect of bond shear modulus, maximum elastic slip strain, and damage curve exponential coefficient on blast-induced response of RC columns. Finally, recommendations are given for modelling the bond slip in numerical analysis of blast-induced responses of RC columns.

miR-140-3p Knockdown Suppresses Cell Proliferation and Fibrogenesis in Hepatic Stellate Cells via PTEN-Mediated AKT/mTOR Signaling

Shi-Min Wu,Tian-Hong Li,Hao Yun,Hong-Wu Ai,Ke-Hui Zhang 연세대학교의과대학 2019 Yonsei medical journal Vol.60 No.6

Purpose: Liver fibrosis is a major cause of morbidity and mortality and the outcome of various chronic liver diseases. Activationof hepatic stellate cells (HSCs) is the key event in liver fibrosis. Studies have confirmed that miR-140-3p plays a potential regulatoryeffect on HSC activation. However, whether miR-140-3p mediates the liver fibrosis remains unknown. Materials and Methods: Expression of miR-140-3p was detected by real-time quantitative PCR (qPCR). Cell proliferation wasmeasured by MTT, while cell apoptosis rate was determined via flow cytometry. Western blot assay was used to detect the expressionof cleaved PARP. The fibrogenic effect was evaluated by expression of α-smooth muscle actin and desmin. Functional experimentswere performed in transforming growth factor β1 (TGF-β1)-induced HSC-T6 cells with transfection of anti-miR-140-3pand/or siPTEN. Target binding between miR-140-3p and PTEN was predicted by the TargetScan database and identified usingluciferase reporter assay and RNA immunoprecipitation. Results: TGF-β1 induced the activation of HSC-T6 cells, and miR-140-3p expression varied according to HSC-T6 cell activationstatus. Knockdown of miR-140-3p reduced cell proliferation and the expressions of α-SMA and desmin, as well as increasedapoptosis, in TGF-β1-induced HSC-T6 cells, which could be blocked by PTEN silencing. Additionally, inactivation of the AKT/mTOR signaling pathway stimulated by miR-140-3p knockdown was abolished when silencing PTEN expression. PTEN was negativelyregulated by miR-140-3p via direct binding in HSC-T6 cells. Conclusion: miR-140-3p is an important mediator in HSC-T6 cell activation, and miR-140-3p knockdown suppresses cell proliferationand fibrogenesis in TGF-β1-induced HSC-T6 cells, indicating that miR-140-3p may be a potential novel molecular targetfor liver fibrosis.

Integrative Modeling of Wireless RF Links for Train-to-Wayside Communication in Railway Tunnel

Shi Pu,Jian-Hong Hao 한국산업정보학회 2012 한국산업정보학회논문지 Vol.17 No.2

In railway tunnel environment, the reliability of a high-data-rate and real-time train-to-wayside communication should be maintained especially when high-speed train moves along the track. In China and Europe, the communication frequency around 900 MHz is widely used for railway applications. At this carrier frequency band, both of the solutions based on continuously laid leaky coaxial cable (LCX) and discretely installed base-station antennas (BSAs), are applied in tunnel radio coverage. Many available works have concentrated on the radio-wave propagation in tunnels by different kinds of prediction models. Most of them solve this problem as natural propagation in a relatively large hollow waveguide, by neglecting the transmitting/receiving (Tx/Rx) components. However, within such confined areas like railway tunnels especially loaded with train, the complex communication environment becomes an important factor that would affect the quality of the signal transmission. This paper will apply a full-wave numerical method to this case, for considering the BSA or LCX, train antennas and their interacted environments, such as the locomotive body, overhead line for power supply, locomotive pantograph, steel rails, ballastless track, tunnel walls, etc.. Involving finite-difference time-domain (FDTD) method and uni-axial anisotropic perfectly matched layer (UPML) technique, the entire wireless RF downlinks of BSA and LCX to tunnel space to train antenna are precisely modeled (so-called integrative modeling technique, IMT). When exciting the BSA and LCX separately, the field distributions of some cross-sections in a rectangular tunnel are presented. It can be found that the influence of the locomotive body and other tunnel environments is very significant. The field coverage on the locomotive roof plane where the train antennas mounted, seems more homogenous when the side-laying position of the BSA or LCX is much higher. Also, much smoother field coverage solution is achieved by choosing LCX for its characteristic of more homogenous electromagnetic wave radiation.

PREPARATION AND CHARACTERIZATION OF ELECTRIC ZAO NANOPARTICLES

HAO-WEI SHI,HONG-ZHEN XIE,JIN-KU LIU,YAN WANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2010 NANO Vol.5 No.4

The white good dispersion zinc aluminium oxide (ZAO) nanoparticles were efficiently prepared by solid phase synthesis method. The morphologies, structures, photoelectricity of the ZAO nanoparticles and the thermochemistry behavior of the precursor were analyzed by TEM, XRD, UV-vis and TG, etc. The phytotoxicity properties of the ZAO nanoparticles were researched for the first time. The results show that the ZAO nanoparticles have a strong inhibition of seed germination and root growth. The biological toxicity of ZAO nanoparticle reduces along with the enlargement of nanoparticle size.

Bond slip modelling and its effect on numerical analysis of blast-induced responses of RC columns

Yanchao Shi,Hong Hao,Zhong-Xian Li 국제구조공학회 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.32 No.2

Reinforced concrete (RC) structures consist of two different materials: concrete and steel bar. The stress transfer behaviour between the two materials through bond plays an important role in the loadcarrying capacity of RC structures, especially when they subject to lateral load such as blast and seismic load. Therefore, bond and slip between concrete and reinforcement bar will affect the response of RC structures under such loads. However, in most numerical analyses of blast-induced structural responses, the perfect bond between concrete and steel bar is often assumed. The main reason is that it is very difficult to model bond slip in the commercial finite element software, especially in hydrodynamic codes. In the present study, a one-dimensional slide line contact model in LS-DYNA for modeling sliding of rebar along a string of concrete nodes is creatively used to model the bond slip between concrete and steel bars in RC structures. In order to model the bond slip accurately, a new approach to define the parameters of the one-dimensional slide line model from common pullout test data is proposed. Reliability and accuracy of the proposed approach and the one-dimensional slide line in modelling the bond slip between concrete and steel bar are demonstrated through comparison of numerical results and experimental data. A case study is then carried out to investigate the bond slip effect on numerical analysis of blast-induced responses of a RC column. Parametric studies are also conducted to investigate the effect of bond shear modulus, maximum elastic slip strain, and damage curve exponential coefficient on blast-induced response of RC columns. Finally, recommendations are given for modelling the bond slip in numerical analysis of blast-induced responses of RC columns.

Two-Stage Fermentation for 2-Ketogluconic Acid Production by Klebsiella pneumoniae

( Yue Hong Sun ),( Dong Wei ),( Ji Ping Shi ),( Ljiljana Mojovi ),( Zeng Sheng Han ),( Jian Hao ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.6

2-Ketogluconic acid production by Klebsiella pneumoniae is a pH-dependent process, strictly proceeding under acidic conditions. Unfortunately, cell growth is inhibited by acidic conditions, resulting in low productivity of 2-ketogluconic acid. To overcome this deficiency, a two-stage fermentation strategy was exploited in the current study. During the first stage, the culture was maintained at neutral pH, favoring cell growth. During the second stage, the culture pH was switched to acidic conditions favoring 2-ketogluconic acid accumulation. Culture parameters, including switching time, dissolved oxygen levels, pH, and temperature were optimized for the fed-batch fermentation. Characteristics of glucose dehydrogenase and gluconate dehydrogenase were revealed in vitro, and the optimal pHs of the two enzymes coincided with the optimum culture pH. Under optimum conditions, a total of 186 g/l 2- ketogluconic acid was produced at 26 h, and the conversion ratio was 0.98 mol/mol. This fermentation strategy has successfully overcome the mismatch between optimum parameters required for cell growth and 2-ketogluconic acid accumulation, and this result has the highest productivity and conversion ratio of 2-ketogluconic and produced by microorganism.

Integrative Modeling of Wireless RF Links for Train-to-Wayside Communication in Railway Tunnel

Pu, Shi,Hao, Jian-Hong Korea Society of Industrial Information Systems 2012 한국산업정보학회논문지 Vol.17 No.2

In railway tunnel environment, the reliability of a high-data-rate and real-time train-to-wayside communication should be maintained especially when high-speed train moves along the track. In China and Europe, the communication frequency around 900 MHz is widely used for railway applications. At this carrier frequency band, both of the solutions based on continuously laid leaky coaxial cable (LCX) and discretely installed base-station antennas (BSAs), are applied in tunnel radio coverage. Many available works have concentrated on the radio-wave propagation in tunnels by different kinds of prediction models. Most of them solve this problem as natural propagation in a relatively large hollow waveguide, by neglecting the transmitting/receiving (Tx/Rx) components. However, within such confined areas like railway tunnels especially loaded with train, the complex communication environment becomes an important factor that would affect the quality of the signal transmission. This paper will apply a full-wave numerical method to this case, for considering the BSA or LCX, train antennas and their interacted environments, such as the locomotive body, overhead line for power supply, locomotive pantograph, steel rails, ballastless track, tunnel walls, etc.. Involving finite-difference time-domain (FDTD) method and uni-axial anisotropic perfectly matched layer (UPML) technique, the entire wireless RF downlinks of BSA and LCX to tunnel space to train antenna are precisely modeled (so-called integrative modeling technique, IMT). When exciting the BSA and LCX separately, the field distributions of some cross-sections in a rectangular tunnel are presented. It can be found that the influence of the locomotive body and other tunnel environments is very significant. The field coverage on the locomotive roof plane where the train antennas mounted, seems more homogenous when the side-laying position of the BSA or LCX is much higher. Also, much smoother field coverage solution is achieved by choosing LCX for its characteristic of more homogenous electromagnetic wave radiation.

Gastrin 유발 위점막 손상에 대한 Nicotine의 보호 효과

박세호(Shi Hao Piao),김동구(Dong Goo Kim),김덕남(De Nan Jin),오정구(Zhen Jiu Wu),홍춘란(Chun Lan Hong),김경환(Kyung Hwan Kim) 대한약리학회 1995 대한약리학잡지 Vol.31 No.3

Conflicting data have been reported on the effect of nicotine on gastric mucosal damage. To elucidate the effect of chronic intermittent nicotine on gastric mucosal damage, intragastric nicotine (5 mg/kg, 10 mg/kg) was administered twice per day for 9 days. Gastric mucosal damage was created by s.c. injection of a large dose (1.2 mg/kg) of pentagastrin followed by pylorus ligation for 6 hours. Nicotine treated rats showed reduced gastric mucosal damage about 50% of the control. To examine the mechanism of the protective effect of nicotine, gastric perfusion experiments were done. Basal acid secretion was not affected by intragastric or intravenous nicotine. However, pentagastrin-stimulated acid secretion markedly inhibited by a bolus injection of nicotine, and this response was dose-related. These data indicates that chronic intermittent administration of nicotine protects gastric mucosa against gastrin-induced gastric mucosal damage, and nicotine-induced inhibition of gastrin-stimulated acid secretion has an important role for the protective effect of nicotine. Considering reports concerning nicotine s aggravating effect on the gastric mucosal damage, it is suggested that the methods of administration of nicotine may be an important decisive factor of the divergent action of nicotine on the gastric mucosa. 위점막 손상에 미치는 영향에 관한 nicotine의 효과는 아직 정설이 없는 형편이다. 본 연구에서는 nicotine이 위점막 손상에 미치는 영향을 보기 위하여 nicotine (5 mg/kg, 10mg/kg)을 9일간 하루에 두번씩 위내 투여하였다. 위점막 손상은 gastrin (1.2 mg/kg)을 피하 주사함과 동시에 유문부결찰을 6시간 동안 시행하므로 야기시켰다. 그 결과 nicotine 투여군에서 현저한 위점막 손상의 감소를 보였다 (대조군의 50%). 이러한 nicotine의 위점막 보호 효과에 대한 기전을 추구하기 위하여 위관류 실험을 시행하였다. Nicotine은 기초 위산 분비에는 영향이 없었으나 gastrin으로 자극된 위산 분비를 현저히 감소시켰고, 이러한 반응은 nicotine 용량에 비례하였다. 이상의 결과로 보아 nicotine의 장기간 간헐적 투여는 gastrin 투여로 인한 위점막 손상에 보호 효과가 있으며, 이러한 효과는 gastrin으로 자극된 위산 분비를 억압하는 nicotine의 효과가 관련될 것으로 생각된다. 또한 nicotine의 위점막 손상 악화 효과를 관찰한 보고들을 고려하면 nicotine의 위점막 손상에 관한 효과는 nicotine의 투여 방법에 따라 전혀 다르게 나타날 수 있을 것으로 생각된다.