Vav3, a GEF for RhoA, Plays a Critical Role under High Glucose Conditions

Jie Sha,나정식,이정옥,김남이,이수경,김지혜,문지욱,김수진,이혜정,최종일,박선화,김현수 대한내분비학회 2014 Endocrinology and metabolism Vol.29 No.3

Background: The role of small GTPase molecules is poorly understood under high glucose conditions. Methods: We analyzed the expression pattern of Vav3 in skeletal muscle C2C12 cells under high glucose culture condition with reverse transcription-polymerase chain reaction and Western blot analysis. We also measured glucose uptake using isotope-labelled glucose. Results: We showed that expression of Vav3 (a guanine nucleotide exchange factor for RhoA) increased. mRNA and protein levels in skeletal muscle C2C12 cells under high glucose conditions. The AMP-activated protein kinase (AMPK) activator AMPK agonist 5-aminoimidazole-4-carboxy-amide-1-d-ribofuranoside (AICAR) suppressed high glucose-induced Vav3 induction. In addition, exposure of cells to high glucose concentration increased the phosphorylation of PAK-1, a molecule downstream of RhoA. The phosphorylation of paxillin, a downstream molecule of PAK-1, was also increased by exposure to high glucose. Phosphorylation of these molecules was not observed in the presence of AICAR, indicating that AMPK is involved in the RhoA signal pathway under high glucose conditions. Knock down of Vav3 enhances metformin-mediated glucose uptake. Inhibition of AMPK blocked the increases of Vav3 knock down-induced glucose uptake. Metformin-mediated Glut4 translocation was also increased by Vav3 knock-down, suggesting that Vav3 is involved in metformin-mediated glucose uptake. Conclusion: These results demonstrate that Vav3 is involved in the process of metformin-mediated glucose regulation.

Study on Treatment of Basic Yellow 28 dye Wastewater by Micro-nano Bubble Ozone Catalytic Oxidation

Jie Wei,Hongwei Sha,Ruonan Wang 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.5

Effect on measurements of anemometers due to a passing high-speed train

Jie Zhang,Guangjun Gao,Sha Huang,Tanghong Liu 한국풍공학회 2015 Wind and Structures, An International Journal (WAS Vol.20 No.4

The three-dimensional unsteady incompressible Reynolds-averaged Navier-Stokes equationsand k-ε double equations turbulent model were used to investigate the effect on the measurements ofanemometers due to a passing high-speed train. Sliding mesh technology in Fluent was utilized to treat themoving boundary problem. The high-speed train considered in this paper was with bogies and inter-carriagegaps. Combined with the results of the wind tunnel test in a published paper, the accuracy of the presentnumerical method was validated to be used for further study. In addition, the difference of slipstreambetween three-car and eight-car grouping models was analyzed, and a series of numerical simulations werecarried out to study the influences of the anemometer heights, the train speeds, the crosswind speeds and thedirections of the induced slipstream on the measurements of the anemometers. The results show that theinfluence factors of the train-induced slipstream are the passing head car and tail car. Using the three-cargrouping model to analyze the train-induced flow is reasonable. The maxima of horizontal slipstreamvelocity tend to reduce as the height of the anemometer increases. With the train speed increasing, therelationship between Vtrain and Vinduced slipstream can be expressed with linear increment. In the absence ofnatural wind conditions, from the head car arriving to the tail car leaving, the induced wind directionchanges about 330°, while under the crosswind condition the wind direction fluctuates around -90°. With thecrosswind speed increasing, the peaks of VX, |VXY -Vwind| of the head car and that of VX of the tail car tend toenlarge. Thus, when anemometers are installed along high-speed railways, it is important to study the effecton the measurements of anemometers due to the train-induced slipstream.

Effect on measurements of anemometers due to a passing high-speed train

Zhang, Jie,Gao, Guangjun,Huang, Sha,Liu, Tanghong Techno-Press 2015 Wind and Structures, An International Journal (WAS Vol.20 No.4

The three-dimensional unsteady incompressible Reynolds-averaged Navier-Stokes equations and k-${\varepsilon}$ double equations turbulent model were used to investigate the effect on the measurements of anemometers due to a passing high-speed train. Sliding mesh technology in Fluent was utilized to treat the moving boundary problem. The high-speed train considered in this paper was with bogies and inter-carriage gaps. Combined with the results of the wind tunnel test in a published paper, the accuracy of the present numerical method was validated to be used for further study. In addition, the difference of slipstream between three-car and eight-car grouping models was analyzed, and a series of numerical simulations were carried out to study the influences of the anemometer heights, the train speeds, the crosswind speeds and the directions of the induced slipstream on the measurements of the anemometers. The results show that the influence factors of the train-induced slipstream are the passing head car and tail car. Using the three-car grouping model to analyze the train-induced flow is reasonable. The maxima of horizontal slipstream velocity tend to reduce as the height of the anemometer increases. With the train speed increasing, the relationship between $V_{train}$ and $V_{induced\;slipstream}$ can be expressed with linear increment. In the absence of natural wind conditions, from the head car arriving to the tail car leaving, the induced wind direction changes about $330^{\circ}$, while under the crosswind condition the wind direction fluctuates around $-90^{\circ}$. With the crosswind speed increasing, the peaks of $V_X,{\mid}V_{XY}-V_{wind}{\mid}$ of the head car and that of $V_X$ of the tail car tend to enlarge. Thus, when anemometers are installed along high-speed railways, it is important to study the effect on the measurements of anemometers due to the train-induced slipstream.

Numerical optimization of transmission bremsstrahlung target for intense pulsed electron beam

Xiao Yu,Jie Shen,Shijian Zhang,Jie Zhang,Nan Zhang,Ivan Sergeevich Egorov,Sha Yan,Chang Tan,Gennady Efimovich Remnev,Xiaoyun Le 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.2

The optimization of a transmission type bremsstrahlung conversion target was carried out with MonteCarlo code FLUKA for intense pulsed electron beams with electron energy of several hundred keV formaximum photon fluence. The photon emission intensity from electrons with energy ranging from300 keV to 1 MeV on tungsten, tantalum and molybdenum targets was calculated with varied targetthicknesses. The research revealed that higher target material element number and electron energy leadsto increased photon fluence. For a certain target material, the target thickness with maximum photonemission fluence exhibits a linear relationship with the electron energy. With certain electron energy andtarget material, the thickness of the target plays a dominant role in increasing the transmission photonintensity, with small target thickness the photon flux is largely restricted by low energy loss of electronsfor photon generation while thick targets may impose extra absorption for the generated photons. Thespatial distribution of bremsstrahlung photon density was analyzed and the optimal target thicknessesfor maximum bremsstrahlung photon fluence were derived versus electron energy on three targetmaterials for a quick determination of optimal target design

Six new dammarane-type triterpene saponins from Panax ginseng flower buds and their cytotoxicity

Ke-Ke Li,Sha-Sha Li,Fei Xu,Xiao-Jie Gong 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.2

Background: Panax ginseng has been used for a variety of medical purposes in eastern countries formore than two thousand years. From the extensive experiences accumulated in its long medication usehistory and the substantial strong evidence in modern research studies, we know that ginseng hasvarious pharmacological activities, such as antitumor, antidiabetic, antioxidant, and cardiovascularsystemeprotective effects. The active chemical constituents of ginseng, ginsenosides, are rich instructural diversity and exhibit a wide range of biological activities. Methods: Ginsenoside constituents from P. ginseng flower buds were isolated and purified by variouschromatographic methods, and their structures were identified by spectroscopic analysis and comparisonwith the reported data. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H- tetrazolium bromidemethod was used to test their cytotoxic effects on three human cancer cell lines. Results: Six ginsenosides, namely 6’emalonyl formyl ginsenoside F1 (1), 3beacetoxyl ginsenoside F1 (2),ginsenoside Rh24 (6), ginsenoside Rh25 (7), 7behydroxyl ginsenoside Rd (8) and ginsenoside Rh26 (10)were isolated and elucidated as new compounds, together with four known compounds (3e5 and 9). Inaddition, the cytotoxicity of these isolated compounds was shown as half inhibitory concentration values,a tentative structureeactivity relationship was also discussed based on the results of our bioassay. Conclusion: The study of chemical constituents was useful for the quality control of P. ginseng flowerbuds. The study on antitumor activities showed that new Compound 1 exhibited moderate cytotoxicactivities against HL-60, MGC80-3 and Hep-G2 with half inhibitory concentration values of 16.74, 29.51and 20.48 mM, respectively.

Six new dammarane-type triterpene saponins from Panax ginseng flower buds and their cytotoxicity

Li, Ke-Ke,Li, Sha-Sha,Xu, Fei,Gong, Xiao-Jie The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.2

Background: Panax ginseng has been used for a variety of medical purposes in eastern countries for more than two thousand years. From the extensive experiences accumulated in its long medication use history and the substantial strong evidence in modern research studies, we know that ginseng has various pharmacological activities, such as antitumor, antidiabetic, antioxidant, and cardiovascular system-protective effects. The active chemical constituents of ginseng, ginsenosides, are rich in structural diversity and exhibit a wide range of biological activities. Methods: Ginsenoside constituents from P. ginseng flower buds were isolated and purified by various chromatographic methods, and their structures were identified by spectroscopic analysis and comparison with the reported data. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H- tetrazolium bromide method was used to test their cytotoxic effects on three human cancer cell lines. Results: Six ginsenosides, namely 6'-malonyl formyl ginsenoside F₁ (1), 3β-acetoxyl ginsenoside F₁ (2), ginsenoside Rh₂₄ (6), ginsenoside Rh₂₅ (7), 7β-hydroxyl ginsenoside Rd (8) and ginsenoside Rh₂₆ (10) were isolated and elucidated as new compounds, together with four known compounds (3-5 and 9). In addition, the cytotoxicity of these isolated compounds was shown as half inhibitory concentration values, a tentative structure-activity relationship was also discussed based on the results of our bioassay. Conclusion: The study of chemical constituents was useful for the quality control of P. ginseng flower buds. The study on antitumor activities showed that new Compound 1 exhibited moderate cytotoxic activities against HL-60, MGC80-3 and Hep-G2 with half inhibitory concentration values of 16.74, 29.51 and 20.48 μM, respectively.

High Capacity Information Hiding Method Based on Pixel-value Adjustment with Modulus Operation

( Teng Li Yu Zhang ),( Sha Wang ),( Jun-jie Sun ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.4

Through information hiding technique, secret message can be hidden in pictures. Stego-image quality and hiding capacity are two important metrics for information hiding. To enhance these metrics, many schemes were proposed by scholars in recent years. Some of them are effective and successful, but there is still a room for further improvement. A high capacity information hiding scheme (PAMO, Pixel-value Adjustment with Modulus Operation Algorithm) is introduced in this paper. PAMO scheme uses pixel value adjustment with modulus operation to hide confidential data in cover-image. PAMO scheme and some referenced schemes are implemented in Python and experiments are carried out to evaluate their performance. In the experiments, PAMO scheme shows better performance than other methods do. When secret message length is less than 72000 bits, the highest hiding capacity of PAMO can reach 7 bits per pixel, at the same time the PSNR of stego-images is greater than 30 dB.

Bioactive Compounds and Chemical Biology : Purification and Characterization of Thermostable Agarase from Bacillus sp. BI-3, a Thermophilic Bacterium Isolated from Hot Spring

( Jiang Li ),( Yu Jie Sha ),( Dewi Seswita Zilda ),( Qiu Shi Hu ),( Pei Qing He ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.1

An extracellular agarase was purified from Bacillus sp. BI-3, a thermophilic agar-degrading bacterium isolated from a hot spring in Indonesia. The purified agarase revealed a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with an apparent molecular mass of 58 kDa. The optimum pH and temperature of the agarase were 6.4 and 70oC, respectively. The activity of the agarase was stable at high temperatures, and more than 50% activity was retained at 80oC for 15 min. Furthermore, the enzyme was stable in the pH range of 5.8?8.0, and more than 60% of the residual activity was retained. Significant activation of the agarase was observed in the presence of K+, Na+, Ca2+, Mg2+, and Sr2+; on the other hand, Ba2+, Zn2+, Cu2+, Mn2+, Co2+, Fe2+, and EDTA inhibited or inactivated the enzyme activity. The components of the hydrolytic product analyzed by thin-layer chromatography showed that the agarase mainly produced neoagarobiose. This study is the first to present evidence of agarolytic activity in aerobic thermophilic bacteria.

Antioxidant Activity of Novel Casein-Derived Peptides with Microbial Proteases as Characterized via Keap1-Nrf2 Pathway in HepG2 Cells

( Xiao Zhao ),( Ya-juan Cui ),( Sha-sha Bai ),( Zhi-jie Yang ),( Miao-cai ),( Sarah Megrous ),( Tariq Aziz ),( Abid Sarwar ),( Dong Li ),( Zhen-nai Yang ) 한국미생물 · 생명공학회 2021 Journal of microbiology and biotechnology Vol.31 No.8

Casein-derived antioxidant peptides by using microbial proteases have gained increasing attention. Combination of two microbial proteases, Protin SD-NY10 and Protease A “Amano” 2SD, was employed to hydrolyze casein to obtain potential antioxidant peptides that were identified by LC-MS/MS, chemically synthesized and characterized in a oxidatively damaged HepG2 cell model. Four peptides, YQLD, FSDIPNPIGSEN, FSDIPNPIGSE, YFYP were found to possess high 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability. Evaluation with HepG2 cells showed that the 4 peptides at low concentrations (< 1.0 mg/ml) protected the cells against oxidative damage. The 4 peptides exhibited different levels of antioxidant activity by stimulating mRNA and protein expression of the antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), as well as nuclear factor erythroid-2-related factor 2 (Nrf2), but decreasing the mRNA expression of Kelch-like ECH-associated protein 1 (Keap1). Furthermore, these peptides decreased production of reactive oxygen species (ROS) and malondialdehyde (MDA), but increased glutathione (GSH) production in HepG2 cells. Therefore, the 4 casein-derived peptides obtained by using microbial proteases exhibited different antioxidant activity by activating the Keap1-Nrf2 signaling pathway, and they could serve as potential antioxidant agents in functional foods or pharmaceutic preparation.