Sclareol Protects Staphylococcus aureus-Induced Lung Cell Injury via Inhibiting Alpha-Hemolysin Expression

( Ouyang Ping ),( Sun Mao ),( He Xuewen ),( Wang Kaiyu ),( Yin Zhongqiong ),( Fu Hualin ),( Li Yinglun ),( Geng Yi ),( Shu Gang ),( He Changliang ),( Liang Xiaoxia ),( Lai Weiming ),( Li Lixia ),( Zou 한국미생물 · 생명공학회 2017 Journal of microbiology and biotechnology Vol.27 No.1

Staphylococcus aureus (S. aureus) is a common gram-positive bacterium that causes serious infections in humans and animals. With the continuous emergence of methicillin-resistant S. aureus (MRSA) strains, antibiotics have limited efficacy in treating MRSA infections. Accordingly, novel agents that act on new targets are desperately needed to combat these infections. S. aureus alpha-hemolysin plays an indispensable role in its pathogenicity. In this study, we demonstrate that sclareol, a fragrant chemical compound found in clary sage, can prominently decrease alpha-hemolysin secretion in S. aureus strain USA300 at sub-inhibitory concentrations. Hemolysis assays, western-blotting, and RT-PCR were used to detect the production of alpha-hemolysin in the culture supernatant. When USA300 was co-cultured with A549 epithelial cells, sclareol could protect the A549 cells at a final concentration of 8 μg/ml. The protective capability of sclareol against the USA300-mediated injury of A549 cells was further shown by cytotoxicity assays and live/dead analysis. In conclusion, sclareol was shown to inhibit the production of S. aureus alpha-hemolysin. Sclareol has potential for development as a new agent to treat S. aureus infections.

기호학 시각으로 창사시를 예시로 분석한 도시 랜드마크 도형 표시 연구

어우양리(Ouyang Li),성민선(Minsun Sung) 한국기초조형학회 2020 한국기초조형학회 학술발표논문집 Vol.2020 No.11

Improvement of Welan Gum Production and Redistribution of Metabolic Flux under pH Control Process in Alcaligenes sp. CGMCC2428

Hui Li,Sha Li,Hong Xu,Xiao-Ye Chen,Ping-Kai Ouyang 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.2

Batch fermentations of welan gum from Alcaligenes sp. CGMCC2428 at pH values of 5.5 ~ 7.0were studied. Based on the kinetic analysis, a pH control process for improving welan production was developed. By maintaining the culture pH at 7.0, the process significantly improved the maximal welan concentration and productivity to reach 25.1 ± 0.65 g/L and 0.42 ± 0.003 g/L/h, respectively,compared with those in native pH processes where pH value would decrease from 7.0 to 5.1 (18.5 ± 0.72 g/L and 0.28 ± 0.002 g/L/h). This improvement may be due to the increased metabolic flux of glucose-1-phosphate to welan induced by pH control process. Furthermore, scale-up fermentation under controlled pH was implemented using 300-L fermentor. The highest welan concentration of 27.5± 0.97 g/L was obtained. This simplified process proved effective in industry fermentation for high welan production.

Strain Improvement and Metabolic Flux Modeling of Wild-type and Mutant Alcaligenes sp. NX-3 for Synthesis of Exopolysaccharide Welan Gum

Hui Li,Hong Xu,Sha Li,Hao Xu,Chaojiang Guo,Pingkai Ouyang,Hanjie Ying 한국생물공학회 2010 Biotechnology and Bioprocess Engineering Vol.15 No.5

Low-energy nitrogen ion beam implantation technique was used for the strain improvement of Alcaligenes sp. NX-3 for the production of exopolysaccharide welan gum. A high welan gum producing mutant, Alcaligenes sp. NX-3-1, was obtained through 20 keV N+ ion beam irradiation. Starting at a concentration of 50 g/L of glucose, mutant NX-3-1 produced 25.0 g/L of welan gum after 66 h of cultivation in a 7.5 L bioreactor, which was 34.4% higher than that produced by the wild-type strain. The results of metabolic flux analysis showed that the glucose-6-phosphate and acetyl coenzyme A nodes were the principle and flexible nodes, respectively. At the glucose-6-phosphate node, the fraction of carbon measured from glucose-6-phosphate to glucose-1-phosphate was enhanced after mutagenesis, which indicated that more flux was used to synthesize welan gum in the mutant. By analyzing the activities of related enzymes in the biosynthetic pathway of sugar nucleotides essential for welan gum production, we found that the specific activities of phosphoglucomutase, UDP-glucose pyrophosphorylase,UDP-glucose dehydrogenase, and dTDP-glucose pyrophosphorylase in the mutant strain were higher than those in the wild-type strain. These improvements in enzyme activities could be due to the affected of ion beam implantation.

Effects of the Size and Oxidation of Graphene Oxide on Crop Quality and Specific Molectular Pathways

Xiaokang Li,Li Mu,Dandan Li,Shaohu Ouyang,Caijiao He,Xiangang Hu 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

A Secure Sharing Mechanism for Data Resources in Extended Virtual Machine System

Yunfa Li,Jian Wan,Rong Ouyang,Wei Zhang,Wanqing Li 보안공학연구지원센터 2012 International Journal of Security and Its Applicat Vol.6 No.2

Elevated TRAF4 expression impaired LPS-induced autophagy in mesenchymal stem cells from ankylosing spondylitis patients

Jinteng Li,Peng Wang,Zhongyu Xie,Rui Yang,Yuxi Li,Xiaohua Wu,Hongjun Su,Wen Deng,Shan Wang,Zhenhua Liu,Shuizhong Cen,Yi Ouyang,Yanfeng Wu,Huiyong Shen 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

Ankylosing spondylitis (AS) is a type of autoimmune disease that predominantly affects the spine and sacroiliac joints. However, the pathogenesis of AS remains unclear. Some evidence indicates that infection with bacteria, especially Gram-negative bacteria, may have an important role in the onset and progression of AS. Recently, many studies have demonstrated that mesenchymal stem cells (MSCs) dysfunction may contribute to the pathogenesis of many rheumatic diseases. We previously demonstrated that MSCs from AS patients exhibited markedly enhanced osteogenic differentiation capacity in vitro under non-inflammatory conditions. However, the properties of MSCs from AS patients in an inflammatory environment have never been explored. Lipopolysaccharide (LPS), a proinflammatory substance derived from the outer membrane of Gram-negative bacteria, can alter the status and function of MSCs. However, whether MSCs from AS patients exhibit abnormal responses to LPS stimulation has not been reported. Autophagy is a lysosome-mediated catabolic process that participates in many physiological and pathological processes. The link between autophagy and AS remains largely unknown. The level of autophagy in ASMSCs after LPS stimulation remains to be addressed. In this study, we demonstrated that although the basal level of autophagy did not differ between MSCs from healthy donors (HDMSCs) and ASMSCs, LPS-induced autophagy was weaker in ASMSCs than in HDMSCs. Specifically, increased TRAF4 expression in ASMSCs impaired LPS-induced autophagy, potentially by inhibiting the phosphorylation of Beclin-1. These data may provide further insight into ASMSC dysfunction and the precise mechanism underlying the pathogenesis of AS.

Determination and prediction of amino acid digestibility in brown rice for growing-finishing pigs

Ouyang Qing,Li Rui,Feng Ganyi,Hou Gaifeng,Jiang Xianji,Liu Xiaojie,Tang Hui,Long Ciming,Yin Jie,Yin Yulong 아세아·태평양축산학회 2024 Animal Bioscience Vol.37 No.8

Objective: The experiment aimed to determine the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in 10 brown rice samples fed to pigs, and to construct predictive models for SID of CP and AA based on the physical characteristics and chemical composition of brown rice.Methods: Twenty-two cannulated pigs (initial body weight: 42.0±1.2 kg) were assigned to a replicated 11×3 incomplete Latin square design, including an N-free diet and 10 brown rice diets. Each period included 5 d adaptation and 2 d ileal digesta collection. Chromic oxide was added at 0.3% to all the diets as an indigestible marker for calculating the ileal CP and AA digestibility.Results: The coefficients of variation of all detected indices for physical characteristics and chemical composition, except for bulk weight, dry matter (DM) and gross energy, in 10 brown rice samples were greater than 10%. The SID of CP, lysine (Lys), methionine, threonine (Thr), and tryptophan (Trp) in brown rice was 77.2% (62.6% to 85.5%), 87.5% (80.3% to 94.3%), 89.2% (78.9% to 98.9%), 55.4% (46.1% to 67.6%) and 92.5% (86.3% to 96.3%), respectively. The best prediction equations for the SID of CP, Lys, Thr, and Trp were as following, SIDCP = –664.181+8.484×DM (R2 = 0.40), SIDLys = 53.126+6.031×ether extract (EE)+0.893×thousand-kernel volume (R2 = 0.66), SIDThr = 39.916+7.843×EE (R2 = 0.41), and SIDTrp = –361.588+4.891×DM+0.387×total starch (R2 = 0.85).Conclusion: Overall, a great variation exists among 10 sources of brown rice, and the thousand-grain volume, DM, EE, and total starch can be used as the key predictors for SID of CP and AA. Objective: The experiment aimed to determine the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in 10 brown rice samples fed to pigs, and to construct predictive models for SID of CP and AA based on the physical characteristics and chemical composition of brown rice. Methods: Twenty-two cannulated pigs (initial body weight: 42.0±1.2 kg) were assigned to a replicated 11×3 incomplete Latin square design, including an N-free diet and 10 brown rice diets. Each period included 5 d adaptation and 2 d ileal digesta collection. Chromic oxide was added at 0.3% to all the diets as an indigestible marker for calculating the ileal CP and AA digestibility. Results: The coefficients of variation of all detected indices for physical characteristics and chemical composition, except for bulk weight, dry matter (DM) and gross energy, in 10 brown rice samples were greater than 10%. The SID of CP, lysine (Lys), methionine, threonine (Thr), and tryptophan (Trp) in brown rice was 77.2% (62.6% to 85.5%), 87.5% (80.3% to 94.3%), 89.2% (78.9% to 98.9%), 55.4% (46.1% to 67.6%) and 92.5% (86.3% to 96.3%), respectively. The best prediction equations for the SID of CP, Lys, Thr, and Trp were as following, SIDCP = –664.181+8.484×DM (R2 = 0.40), SIDLys = 53.126+6.031×ether extract (EE)+0.893×thousand-kernel volume (R2 = 0.66), SIDThr = 39.916+7.843×EE (R2 = 0.41), and SIDTrp = –361.588+4.891×DM+0.387×total starch (R2 = 0.85). Conclusion: Overall, a great variation exists among 10 sources of brown rice, and the thousand-grain volume, DM, EE, and total starch can be used as the key predictors for SID of CP and AA.

A MODEL OF INTERMARRIAGE INVOLVING ATTRIBUTE EXCHANGE

Li, Shaomin,Jow-Ching Tu, Edward,Ouyang, Ming 연세대학교 동서문제연구원 2002 Global economic review Vol.31 No.3

The increasing pace of globalization has significantly affected our lives in many profound ways. One of the consequences of globalization is the rise of intermarriage, i.e., the marriage between couples of different nationalities or different social, economic, religious, or racial backgrounds. Since our understanding of intermarriage is limited, this paper attempts to shed lights on intermarriage by developing a formal model based on attribute exchange. After examining the motivation and micro and macro consequences of intermarriages, our model shows that different value systems regarding marital attributes among different groups drive individuals with attributes valued lower in their group to seek intermarriage. As a result, the essence of intermarriages is the movement of attributes from groups in which such attributes are relatively abundant to groups where the same attributes are relatively scarce. Thus, intermarriage makes individuals with attributes valued lower in their original groups better off. At the inter-societal (or inter-group) level, the equilibrium of intermarriage is determined by the relative scarcity of marital attributes in different groups (societies). In the long run, intermarriages converge different groups in terms of their value systems regarding marriage.

Differential evolution algorithm with improved crossover operation for combined heat and power economic dynamic dispatch problem with wind power

Li Mengdi,Zou Dexuan,Ouyang Haibin 한국CDE학회 2023 Journal of computational design and engineering Vol.10 No.4

This paper proposes a differential evolution algorithm with improved crossover operation (ICRDE) to deal with combined heat and power dynamic economic dispatch (CHPDED) problems with wind power. First, the improved crossover operation is used to maintain the population diversity by using original individuals, first mutated individuals, and second mutated individuals. Second, the scaling factor and weighted factor are incorporated into the mutation operation to improve the convergence efficiency of the algorithm. Third, adaptive control parameters are introduced to balance local exploitation and global exploration. Moreover, after being updated by the mutation and crossover operation of ICRDE at each generation, the solutions of ICRDE will be further amended using a constraint handling method, which improves the chance of acquiring feasible solutions. Experimental results demonstrate that ICRDE has strong global optimization ability and surpasses the compared algorithms for the CEC2017 benchmark functions, the combined heat and power economic dispatch problems, and the CHPDED problem with and without wind power.