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Verification of Anti-Inflammatory Effects of Strawberry (Fragaria x ananassa var. 'Seolhyang') Stems on Macrophages Stimulated by Lipopolysaccharides (LPS로 자극된 대식세포에 대한 딸기 줄기의 항염증 효능 검증)

  • Dan-Hee Yoo;In-Chul Lee
    • Microbiology and Biotechnology Letters
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    • v.51 no.3
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    • pp.280-288
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    • 2023
  • In strawberry farming, most parts of strawberry stems but the fruit have been dumped. Therefore, this study attempted to investigate the antioxidant and anti-inflammatory effects of strawberry stems which are thrown away after farming. For this, strawberry stem extracts were obtained, using hot water and 70% ethanol. First, total polyphenol contents of the hot water and ethanol extract were checked (265.4 ± 0.12 mg TAE/100 g, 503.88 ± 0.2 mg TAE/100 g). For analysis of antioxidant activities, electron donating ability (EDA) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity were measured. Both extracts increased in a dose-dependent fashion, and similar effects with vitamin C (control group) were confirmed. In terms of cell viability of the hot water and ethanol extracts of strawberry stems, 'RAW 264.7' was 99% or higher at 500 ㎍/ml. In addition, cell experiments were conducted at 50, 100 and 500 ㎍/ml where cell viability is above 99%. In terms of inhibition of the inflammatory mediator 'nitric oxide (NO)', the hot water and ethanol extracts of strawberry stems were 37.9% and 38.8% respectively, confirming the inhibition of NO production. To check anti-inflammatory activities, protein and mRNA expressions of 'iNOS' and 'COX-2' were measured, using RAW 264.7. Compared to the LPS group, the protein expression of the inflammatory mediators was inhibited in the hot water and ethanol extract-treated groups. The above results confirmed that the hot water and ethanol extracts of strawberry stems are valuable as natural substances with antioxidant and anti-inflammatory activities.

The Relations between Financial Constraints and Dividend Smoothing of Innovative Small and Medium Sized Enterprises (혁신형 중소기업의 재무적 제약과 배당스무딩간의 관계)

  • Shin, Min-Shik;Kim, Soo-Eun
    • Korean small business review
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    • v.31 no.4
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    • pp.67-93
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    • 2009
  • The purpose of this paper is to explore the relations between financial constraints and dividend smoothing of innovative small and medium sized enterprises(SMEs) listed on Korea Securities Market and Kosdaq Market of Korea Exchange. The innovative SMEs is defined as the firms with high level of R&D intensity which is measured by (R&D investment/total sales) ratio, according to Chauvin and Hirschey (1993). The R&D investment plays an important role as the innovative driver that can increase the future growth opportunity and profitability of the firms. Therefore, the R&D investment have large, positive, and consistent influences on the market value of the firm. In this point of view, we expect that the innovative SMEs can adjust dividend payment faster than the noninnovative SMEs, on the ground of their future growth opportunity and profitability. And also, we expect that the financial unconstrained firms can adjust dividend payment faster than the financial constrained firms, on the ground of their financing ability of investment funds through the market accessibility. Aivazian et al.(2006) exert that the financial unconstrained firms with the high accessibility to capital market can adjust dividend payment faster than the financial constrained firms. We collect the sample firms among the total SMEs listed on Korea Securities Market and Kosdaq Market of Korea Exchange during the periods from January 1999 to December 2007 from the KIS Value Library database. The total number of firm-year observations of the total sample firms throughout the entire period is 5,544, the number of firm-year observations of the dividend firms is 2,919, and the number of firm-year observations of the non-dividend firms is 2,625. About 53%(or 2,919) of these total 5,544 observations involve firms that make a dividend payment. The dividend firms are divided into two groups according to the R&D intensity, such as the innovative SMEs with larger than median of R&D intensity and the noninnovative SMEs with smaller than median of R&D intensity. The number of firm-year observations of the innovative SMEs is 1,506, and the number of firm-year observations of the noninnovative SMEs is 1,413. Furthermore, the innovative SMEs are divided into two groups according to level of financial constraints, such as the financial unconstrained firms and the financial constrained firms. The number of firm-year observations of the former is 894, and the number of firm-year observations of the latter is 612. Although all available firm-year observations of the dividend firms are collected, deletions are made in the case of financial industries such as banks, securities company, insurance company, and other financial services company, because their capital structure and business style are widely different from the general manufacturing firms. The stock repurchase was involved in dividend payment because Grullon and Michaely (2002) examined the substitution hypothesis between dividends and stock repurchases. However, our data structure is an unbalanced panel data since there is no requirement that the firm-year observations data are all available for each firms during the entire periods from January 1999 to December 2007 from the KIS Value Library database. We firstly estimate the classic Lintner(1956) dividend adjustment model, where the decision to smooth dividend or to adopt a residual dividend policy depends on financial constraints measured by market accessibility. Lintner model indicates that firms maintain stable and long run target payout ratio, and that firms adjust partially the gap between current payout rato and target payout ratio each year. In the Lintner model, dependent variable is the current dividend per share(DPSt), and independent variables are the past dividend per share(DPSt-1) and the current earnings per share(EPSt). We hypothesized that firms adjust partially the gap between the current dividend per share(DPSt) and the target payout ratio(Ω) each year, when the past dividend per share(DPSt-1) deviate from the target payout ratio(Ω). We secondly estimate the expansion model that extend the Lintner model by including the determinants suggested by the major theories of dividend, namely, residual dividend theory, dividend signaling theory, agency theory, catering theory, and transactions cost theory. In the expansion model, dependent variable is the current dividend per share(DPSt), explanatory variables are the past dividend per share(DPSt-1) and the current earnings per share(EPSt), and control variables are the current capital expenditure ratio(CEAt), the current leverage ratio(LEVt), the current operating return on assets(ROAt), the current business risk(RISKt), the current trading volume turnover ratio(TURNt), and the current dividend premium(DPREMt). In these control variables, CEAt, LEVt, and ROAt are the determinants suggested by the residual dividend theory and the agency theory, ROAt and RISKt are the determinants suggested by the dividend signaling theory, TURNt is the determinant suggested by the transactions cost theory, and DPREMt is the determinant suggested by the catering theory. Furthermore, we thirdly estimate the Lintner model and the expansion model by using the panel data of the financial unconstrained firms and the financial constrained firms, that are divided into two groups according to level of financial constraints. We expect that the financial unconstrained firms can adjust dividend payment faster than the financial constrained firms, because the former can finance more easily the investment funds through the market accessibility than the latter. We analyzed descriptive statistics such as mean, standard deviation, and median to delete the outliers from the panel data, conducted one way analysis of variance to check up the industry-specfic effects, and conducted difference test of firms characteristic variables between innovative SMEs and noninnovative SMEs as well as difference test of firms characteristic variables between financial unconstrained firms and financial constrained firms. We also conducted the correlation analysis and the variance inflation factors analysis to detect any multicollinearity among the independent variables. Both of the correlation coefficients and the variance inflation factors are roughly low to the extent that may be ignored the multicollinearity among the independent variables. Furthermore, we estimate both of the Lintner model and the expansion model using the panel regression analysis. We firstly test the time-specific effects and the firm-specific effects may be involved in our panel data through the Lagrange multiplier test that was proposed by Breusch and Pagan(1980), and secondly conduct Hausman test to prove that fixed effect model is fitter with our panel data than the random effect model. The main results of this study can be summarized as follows. The determinants suggested by the major theories of dividend, namely, residual dividend theory, dividend signaling theory, agency theory, catering theory, and transactions cost theory explain significantly the dividend policy of the innovative SMEs. Lintner model indicates that firms maintain stable and long run target payout ratio, and that firms adjust partially the gap between the current payout ratio and the target payout ratio each year. In the core variables of Lintner model, the past dividend per share has more effects to dividend smoothing than the current earnings per share. These results suggest that the innovative SMEs maintain stable and long run dividend policy which sustains the past dividend per share level without corporate special reasons. The main results show that dividend adjustment speed of the innovative SMEs is faster than that of the noninnovative SMEs. This means that the innovative SMEs with high level of R&D intensity can adjust dividend payment faster than the noninnovative SMEs, on the ground of their future growth opportunity and profitability. The other main results show that dividend adjustment speed of the financial unconstrained SMEs is faster than that of the financial constrained SMEs. This means that the financial unconstrained firms with high accessibility to capital market can adjust dividend payment faster than the financial constrained firms, on the ground of their financing ability of investment funds through the market accessibility. Futhermore, the other additional results show that dividend adjustment speed of the innovative SMEs classified by the Small and Medium Business Administration is faster than that of the unclassified SMEs. They are linked with various financial policies and services such as credit guaranteed service, policy fund for SMEs, venture investment fund, insurance program, and so on. In conclusion, the past dividend per share and the current earnings per share suggested by the Lintner model explain mainly dividend adjustment speed of the innovative SMEs, and also the financial constraints explain partially. Therefore, if managers can properly understand of the relations between financial constraints and dividend smoothing of innovative SMEs, they can maintain stable and long run dividend policy of the innovative SMEs through dividend smoothing. These are encouraging results for Korea government, that is, the Small and Medium Business Administration as it has implemented many policies to commit to the innovative SMEs. This paper may have a few limitations because it may be only early study about the relations between financial constraints and dividend smoothing of the innovative SMEs. Specifically, this paper may not adequately capture all of the subtle features of the innovative SMEs and the financial unconstrained SMEs. Therefore, we think that it is necessary to expand sample firms and control variables, and use more elaborate analysis methods in the future studies.

A Study on the Effect of the Introduction Characteristics of Cloud Computing Services on the Performance Expectancy and the Intention to Use: From the Perspective of the Innovation Diffusion Theory (클라우드 컴퓨팅 서비스의 도입특성이 조직의 성과기대 및 사용의도에 미치는 영향에 관한 연구: 혁신확산 이론 관점)

  • Lim, Jae Su;Oh, Jay In
    • Asia pacific journal of information systems
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    • v.22 no.3
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    • pp.99-124
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    • 2012
  • Our society has long been talking about necessity for innovation. Since companies in particular need to carry out business innovation in their overall processes, they have attempted to apply many innovation factors on sites and become to pay more attention to their innovation. In order to achieve this goal, companies has applied various information technologies (IT) on sites as a means of innovation, and consequently IT have been greatly developed. It is natural for the field of IT to have faced another revolution which is called cloud computing, which is expected to result in innovative changes in software application via the Internet, data storing, the use of devices, and their operations. As a vehicle of innovation, cloud computing is expected to lead the changes and advancement of our society and the business world. Although many scholars have researched on a variety of topics regarding the innovation via IT, few studies have dealt with the issue of could computing as IT. Thus, the purpose of this paper is to set the variables of innovation attributes based on the previous articles as the characteristic variables and clarify how these variables affect "Performance Expectancy" of companies and the intention of using cloud computing. The result from the analysis of data collected in this study is as follows. The study utilized a research model developed on the innovation diffusion theory to identify influences on the adaptation and spreading IT for cloud computing services. Second, this study summarized the characteristics of cloud computing services as a new concept that introduces innovation at its early stage of adaptation for companies. Third, a theoretical model is provided that relates to the future innovation by suggesting variables for innovation characteristics to adopt cloud computing services. Finally, this study identified the factors affecting expectation and the intention to use the cloud computing service for the companies that consider adopting the cloud computing service. As the parameter and dependent variable respectively, the study deploys the independent variables that are aligned with the characteristics of the cloud computing services based on the innovation diffusion model, and utilizes the expectation for performance and Intention to Use based on the UTAUT theory. Independent variables for the research model include Relative Advantage, Complexity, Compatibility, Cost Saving, Trialability, and Observability. In addition, 'Acceptance for Adaptation' is applied as an adjustment variable to verify the influences on the expected performances from the cloud computing service. The validity of the research model was secured by performing factor analysis and reliability analysis. After confirmatory factor analysis is conducted using AMOS 7.0, the 20 hypotheses are verified through the analysis of the structural equation model, accepting 12 hypotheses among 20. For example, Relative Advantage turned out to have the positive effect both on Individual Performance and on Strategic Performance from the verification of hypothesis, while it showed meaningful correlation to affect Intention to Use directly. This indicates that many articles on the diffusion related Relative Advantage as the most important factor to predict the rate to accept innovation. From the viewpoint of the influence on Performance Expectancy among Compatibility and Cost Saving, Compatibility has the positive effect on both Individual Performance and on Strategic Performance, while it showed meaningful correlation with Intention to Use. However, the topic of the cloud computing service has become a strategic issue for adoption in companies, Cost Saving turns out to affect Individual Performance without a significant influence on Intention to Use. This indicates that companies expect practical performances such as time and cost saving and financial improvements through the adoption of the cloud computing service in the environment of the budget squeezing from the global economic crisis from 2008. Likewise, this positively affects the strategic performance in companies. In terms of effects, Trialability is proved to give no effects on Performance Expectancy. This indicates that the participants of the survey are willing to afford the risk from the high uncertainty caused by innovation, because they positively pursue information about new ideas as innovators and early adopter. In addition, they believe it is unnecessary to test the cloud computing service before the adoption, because there are various types of the cloud computing service. However, Observability positively affected both Individual Performance and Strategic Performance. It also showed meaningful correlation with Intention to Use. From the analysis of the direct effects on Intention to Use by innovative characteristics for the cloud computing service except the parameters, the innovative characteristics for the cloud computing service showed the positive influence on Relative Advantage, Compatibility and Observability while Complexity, Cost saving and the likelihood for the attempt did not affect Intention to Use. While the practical verification that was believed to be the most important factor on Performance Expectancy by characteristics for cloud computing service, Relative Advantage, Compatibility and Observability showed significant correlation with the various causes and effect analysis. Cost Saving showed a significant relation with Strategic Performance in companies, which indicates that the cost to build and operate IT is the burden of the management. Thus, the cloud computing service reflected the expectation as an alternative to reduce the investment and operational cost for IT infrastructure due to the recent economic crisis. The cloud computing service is not pervasive in the business world, but it is rapidly spreading all over the world, because of its inherited merits and benefits. Moreover, results of this research regarding the diffusion innovation are more or less different from those of the existing articles. This seems to be caused by the fact that the cloud computing service has a strong innovative factor that results in a new paradigm shift while most IT that are based on the theory of innovation diffusion are limited to companies and organizations. In addition, the participants in this study are believed to play an important role as innovators and early adapters to introduce the cloud computing service and to have competency to afford higher uncertainty for innovation. In conclusion, the introduction of the cloud computing service is a critical issue in the business world.

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Biological Control of Tomato and Red Pepper Powdery Mildew using Paenibacillus polymyxa CW (Paenibacillus polymyxa CW를 이용한 고추 및 토마토 흰가루병 방제)

  • Kim, Yong-Ki;Choi, Eun-Jung;Hong, Sung-Jun;Shim, Chang-Ki;Kim, Min-Jeong;Jee, Hyeong-Jin;Park, Jong-Ho;Han, Eun-Jung;Jang, Bo-Kyung;Yun, Jong-Cheul
    • The Korean Journal of Pesticide Science
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    • v.17 no.4
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    • pp.379-387
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    • 2013
  • In order to improve practical utility of agro-microorganisms (AMs) which had been cultured and disseminated to promote plant growth and to control crop diseases, 51 isolates of AMs were collected from 18 agricultural extension centers in local government and screened for multi-functions such as antifungal activity, activities of phosphorus solubilization, IAA and siderophore production, nitrogen fixation, and hydrolytic enzyme activity. Finally we selected one isolate showing good antifungal activity and multi-functions related to plant growth and disease control. The selected isolate, Paenibacillus polymyxa CW, showed good inhibitory effect against plant pathogens, Pyricularia gresea, Colletotrichum acutatum, Fusarium oxysporum, Phomopsis sp., Aspergillus niger, Rhizoctonia solani and Phytophthora capsici. Suppressive effect of P. polymyxa CW against the used plant pathogens except for R. solani was much higher than that of P. polymyxa AC-1 storing in National Academy of Agricultural Science. We found P. polymyxa CW isolate showed good activity in siderophore and IAA formation, and nitrogen fixation. With P. polymyxa CW isolate, siderophore formation activity was similar to that of P. polymyxa AC-1, but IAA formation and nitrogen fixation activity was much higher than that of P. polymyxa AC-1. However neither P. polymyxa CW nor P. polymyxa AC-1 showed hydrolytic enzyme (chitinase, pectinase and cellulase) activity. The treatment of P. polymyxa CW with culture suspension of different cell density ($10^8$, $10^7$. $10^6$ cfu/ml) showed that the highest density reduced incidence of red pepper powdery mildew by 68.3% after 10 days of application. As application density of P. polymyxa CW was decreased, its control efficacy was proportionally decreased. In addition, when P. polymyxa CW was treated to control tomato powdery mildew at the same concentrations and their control effects were investigated after 7 days of inoculation, disease incidence was 0.03, 19.5, 45.7%, respectively, compared to 56.3% that of untreated check. Like red pepper powdery mildew, increase of application density of P. polymyxa CW resulted in increase of its control efficacy proportionally. P. polymyxa CW showed a density-dependent control efficacy against red pepper and tomato powdery mildews. Therefore we think that mode of action of the antagonist for suppressing two powdery mildew diseases might be antibiosis and density of more than $10^8cfu/ml$ was needed to control effectively the two diseases. On this basis, we think that P. polymyxa CW can be a promising control agent for suppressing powdery mildews of red pepper and tomato.

A Study on the Expressed Desire at Discharge of Patients to Use Home Nursing and Affecting Factors of the Desire (퇴원환자의 가정간호 이용의사와 관련 요인)

  • Lee, Ji-Hyun;Lee, Young-Eun;Lee, Myung-Hwa;Sohn, Sue-Kyung
    • The Korean Journal of Rehabilitation Nursing
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    • v.2 no.2
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    • pp.257-270
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    • 1999
  • The purpose of this study is to investigate factors related to the intent of using home nursing of chronic disease patients who got out of a university hospital. For the purpose, the study selected 153 patients who were hospitalized and left K university hospital with diagnoses of cancer, hypertension, diabetes and cerebral vascular accident and ordered to be discharged and performed interviews with them and surveys on their medical records to obtain the following results. For this study a direct-interview survey and medical record review was conducted from June 28 to Aug. 30, 1998. The frequency and mean values were computed to find the characteristics of the study subjects, and $X^2$-test, t-test, factor analysis and multiple logistic regession analysis were applied for the analysis of the data. The following results were obtained. 1) When characteristics of the subjects were examined, men and women occupied for 58.8% and 41.2%, respectively. The subjects were 41.3 years old in aver age and had the monthly aver age earning of 0.99 million won or below, which was the most out of the total subjects at 34.6%. Among the total, 87.6% resided in cities and 12.4 in counties. The most left the hospital with diagnosis of cancer at 51.6%, followed by hyper tension at 24.2%, diabetes at 13.7% and cerebral vascular accident at 7.2%. 2) 93.5% of the selected patients had the intent of using home nursing and 6.5%, didn't. Among those patients having the intent, 85.6% had the intent of paying for home nursing and 14.4%, didn't. The subjects expected that the nursing would be paid 9,143 won in aver age and 47.7% of them preferred national authorities as the main servers. 86.3% of the subjects thought that home nursing business had the main advantage of making it possible to learn nursing methods at home and thereby contributing to improving the ability of patients and their facilities to solve health problems. 3) Relations between the intent of use and characteristics of the subjects such as demography-related social, home environment, disease and physical function characteristics did not show statistically significant differences among one another. Compared to those who had no intent of using home nursing, the group having the intent had more cases of male patients, the age of 39 or below, residence in cities, 5 family member s or more, no existence of home nursing servers, leaving the hospital from a non-hospitalized building, disease development for five months or below, hospitalization for ten days or more, non-hospitalization with in the recent one month, two times or over of hospitalization, leaving the hospital with no demand of special treatment, operation underwent, poor results of treatment, leaving the hospital with demand of rehabilitation services, physical disablement and high evaluation point of daily life. 4) Among those patients having the intent of using home nursing, 47.6% demanded technical nursing and 55.9%, supportive nursing. As technical nursing,' inject into a blood vessel ' and 'treat pustule and teach basic prevention methods occupied for 57.4%, respectively, topping the list. Among demands of supportive nursing, 'observe patients 'status and refer them to hospitals or community resources as available, if necessary' was the most with percent age point of 59.5. Regarding the intent of paying for home nursing, 39.2% of those patients wishing to use the nursing responded paying for technical services and 20.2, supportive services. In detail, 70.0% wanted to pay for a service stated as 'inject into a blood vessel', highest among the former services and 30.7%, a service referred to as 'teaching exercises needed to make the body of patients move', highest among the latter. When this was analyzed in terms of a relation between the need(the need for home nursing) and the demand(the intent of paying for home nursing), The rate of the need to the demand was found two or three times higher in technical nursing(0.82) than in supportive nursing(0.35). In aspects of tech ical nursing, muscle injection(1.26, the 1st rank) was highest in the rate while among aspects of supportive nursing, a service referred to as 'teach exercises needed for making patients move their bodies normally'(0.58, the 1st rank). 5) factors I(satisfaction with hospital services), II(recognition of disease state), III(economy) and IV(period of disease) occupied for 34.4, 13.8, 11.9 and 9.2 percents, respectively among factors related to the intent by the subjects of using home nursing, totaled 59.3%. In conclusion, most of chronic disease patients have the intent of using hospital-based home nursing and satisfaction with hospital services is a factor affecting the intent most. Thus a post-management system is needed to continue providing health management to those patients after they leave the hospital. Further, supportive services should be provided in order that those who are satisfied with hospital services return to their community and live their in dependent lives. Based on these results, the researcher would make the following recommendation. 1) Because home nursing becomes more and more needed due to a sharp increase in chronic disease patients and elderly people, related rules and regulations should be made and implemented. 2) Hospital nurses specializing in home nursing should be cultivated.

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The Effect of Platelets on Endothelin Production in Bovine Pulmonary Artery Endothelial Cells (혈소판이 소 폐동백 내피세포의 Endothelin 생산에 미치는 효과)

  • Lee, Sang-Do;Shim, Tae-Sun;Kwon, Seog-Woon;Ryu, Jin-Sook;Lee, Jae-Dam;Lim, Chae-Man;Koh, Youn-Suck;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.5
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    • pp.1114-1124
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    • 1997
  • Background : Endothelin(ET) is a very potent vasoconstrictive peptide produced by endothelial cells of pulmonary artery. The endothelin level was increased in plasma of primary pulmonary hypertension and acute pulmonary thromboembolism and it was suggested that the endothelin might do a critical role in the cardiopulmonary dysfunction in these two conditions. But the exact mechanism of increase of ET has not been known. In these two conditions, platelet activation and thrombosis are the main pathophysiologic findings. So there is a possibility that the platelet might stimulate endothelin secretion from endothelial cells. Therefore, we performed this study to evaluate the role of platelet and its mediators on endothelin production in bovine pulmonary artery endothelial(BPAE) cells. Method : Bovine pulmonary artery endothelial cells, ATCC certified cell line 209, were cultured and treated with human platelets($10^6{\sim}10^8/ml$), thrombin (0.1~10u/ml), TGF-${\beta}1$(1~100uM), serotonin(1~100uM), and endotoxin(1ug/ml) in a final volume of 500ul for 18 hours. Levels of ir(immunoreactive)-ET in each conditioned medium were measured by a radioimmunoassay specific for ET. Result : The increase of ir-ET levels was platelet number and time dependent over 18 hours. When washed human platelets were added($10^8/ml$), the ir-ET levels were significantly higher than that of control(p<0.05) at 8 and 18 hours after culture. Subthreshold concentration of platelets($10^7/ml$) coincubated with endotoxin(1ug/ml) or subthreshold dose of thrombin(0.1u/ml) stimulated ir-ET secretion from BPAE cells significantly(p<0.05) compared with control. Thrombin(1ug/ml, 10ug/ml) and TGF-${\beta}1$(100pM, 1000pM) significantly increased ir-ET secretion from BP AE cells(p<0.05) compared with control, but serotoin(1~100uM) and endotoxin(1ug/ml) did not stimulate the ir-ET secretion. Conclusions : Platelets stimulate endothelin secretion from bovine pulmonary artery endothelial cells. The mechanism of increase of endothelin secretion seems to be a stimulation by platelet itself or by mediators, such as TGF-${\beta}1$, secreted from activated platelets. And, in this study, the priming effect of platelets on endothelin secretion from BPAE cells could be another possibility.

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PS-341-Induced Apoptosis is Related to JNK-Dependent Caspase 3 Activation and It is Negatively Regulated by PI3K/Akt-Mediated Inactivation of Glycogen Synthase Kinase-$3{\beta}$ in Lung Cancer Cells (폐암세포주에서 PS-341에 의한 아포프토시스에서 JNK와 GSK-$3{\beta}$의 역할 및 상호관련성)

  • Lee, Kyoung-Hee;Lee, Choon-Taek;Kim, Young Whan;Han, Sung Koo;Shim, Young-Soo;Yoo, Chul-Gyu
    • Tuberculosis and Respiratory Diseases
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    • v.57 no.5
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    • pp.449-460
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    • 2004
  • Background : PS-341 is a novel, highly selective and potent proteasome inhibitor, which showed cytotoxicity against some tumor cells. Its anti-tumor activity has been suggested to be associated with modulation of the expression of apoptosis-associated proteins, such as p53, $p21^{WAF/CIP1}$, $p27^{KIP1}$, NF-${\kappa}B$, Bax and Bcl-2. c-Jun N-terminal kinase (JNK) and glycogen synthase kinase-$3{\beta}$ (GSK-$3{\beta}$) are important modulators of apoptosis. However, their role in PS-341-induced apoptosis is unclear. This study was undertaken to elucidate the role of JNK and GSK-$3{\beta}$ in the PS-341-induced apoptosis in lung cancer cells. Method : NCI-H157 and A549 cells were used in the experiments. The cell viability was assayed using the MTT assay and apoptosis was evaluated by proteolysis of PARP. The JNK activity was measured by an in vitro immuno complex kinase assay and by phosphorylation of endogenous c-Jun. The protein expression was evaluated by Western blot analysis. Dominant negative JNK1 (DN-JNK1) and GSK-$3{\beta}$ were overexpressed using plasmid and adenovirus vectors, respectively. Result : PS-341 reduced the cell viability via apoptosis, activated JNK and increased the c-Jun expression. Blocking of the JNK activation by overexpression of DN-JNK1, or pretreatment with SP600125, suppressed the apoptosis induced by PS-341. The activation of caspase 3 was mediated by JNK activation. Blocking of the caspase 3 activation suppressed PS-341-induced apoptosis. PS-341 activated the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, but its blockade enhanced the PS-341-induced cell death via apoptosis. GSK-$3{\beta}$ was inactivated by PS-341 via the PI3K/Akt pathway. Overexpression of constitutively active GSK-$3{\beta}$ enhanced PS-341-induced apoptosis; in contrast, this was suppressed by dominant negative GSK-$3{\beta}$ (DN-GSK-$3{\beta}$). Inactivation of GSK-$3{\beta}$ by pretreatment with lithium chloride or the overexpression of DN-GSK-$3{\beta}$ suppressed both the JNK activation and c-Jun up-regulation induced by PS-341. Conclusion : The JNK/caspase pathway is involved in PS-341-induced apoptosis, which is negatively regulated by the PI3K/Akt-mediated inactivation of GSK-$3{\beta}$ in lung cancer cells.

Protective Effect of Plantago asiatica L. Leaf Ethanolic Extract Against Ferric Nitrilotriacetate-Induced Prostate Oxidative Damage in Rats (랫드에서의 Fe-NTA 유발 산화스트레스에 대한 차전초 에탄올 추출물의 전립선보호 효과)

  • Hong, Seung-Taek;Hong, Chung-Oui;Nam, Mi-Hyun;Ma, Yuan-Yuan;Hong, Yun-Jin;Son, Da-Hee;Chun, Su-Hyun;Lee, Kwang-Won
    • Journal of Food Hygiene and Safety
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    • v.26 no.3
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    • pp.260-265
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    • 2011
  • Plantago asiatica L. (P. asiatica) has been used as one of the popular folk medicines in Asia for human health care practices. Various activities of P. asiatica have been reported, such as anti-oxidant, anti-glycation, anti-inflammatory and hepatoprotective activity. Therefore, the potential of P. asiatica to reduce oxidative stress has been studied in several ways for over 20 years, especially at liver and kidney. However no investigation has been reported revealing its protective effect on prostate. Method: Treatment of P. asiatica leaf ethanolic extract (PLE) (1 g/kg body weight (b.w.), 2 g/kg b.w., or 4 g/kg b.w.) were given separately to animals for pretreatment once per day for 7 days, and on the seventh day ferric nitrilotriacetate (Fe-NTA; 0.24 mmol Fe/kg b.w.), which is known as an oxidative stress-inducer at prostate, was administrated by i.p to negative control group. At the end of the study period, dissection was carried out for detecting the prostate protective effect of PLE. Result: Fe-NTA-treated animals produced reactive oxygen species (ROS) resulting in depletion of antioxidant biomaker, such as glutathione (GSH), glutathione reductase (GR), and glutathione s-transferase (GST) and increase of lipid peroxidation in prostate. However, PLE pretreatment resulted in an increase in the GSH, GST and GR levels concentration dependent manner and in an significant decrease in the levels of lipid peroxidation. Conclusion: Our data suggest that PLE may be effective in protecting oxidative stress-induced damage of prostate, and PLE may be an chemopreventive agent against Fe-NTA-mediated prostate oxidative damage.

Preparation and Characterization of Physicochemical and Sensory Properties of Bread Enriched with Two Types of Wild Grape Extract (제조방법이 다른 두 종류의 머루즙 첨가가 빵의 이화학적 및 관능적 특성에 미치는 영향)

  • Lee, Byung-Yong;Lee, Malp-Eum;O, Jin-Hwan;Kim, Eun-Cho;Surh, Jeong-Hee
    • Korean journal of food and cookery science
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    • v.26 no.5
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    • pp.636-648
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    • 2010
  • Two types of wild grape extracts(WGE) prepared by different methods were added into butter-top bread at different concentrations(0, 5, 10, 15, 20% of water). Then, the resulting breads were analyzed for their physicochemical and sensory properties in order to identify whether or not the WGE-enriched breads were comparable to control bread in terms of qualities and preferences. Wild grape sugar mixture(WGS), which was prepared by osmotic dehydration of wild grape fruits with the same amounts of sugar, presented significantly lower moisture content and titratable acidity as well as higher pH and sugar content compared to wild grape juice(WGJ), which was produced by boiling the fruits in a vacuum jar and squeezing. The pH of the doughs and breads containing WGE tended to decrease with increasing amounts of WGE, and this phenomenon was more appreciable in those containing WGJ than WGS. This was presumably due to the higher contents of tartaric acid in WGJ. For both types of extracts, hardness, gumminess, and chewiness of the doughs decreased with the addition of WGE, nevertheless, which properties were not remained in the resulting breads. This could be partially attributed to the relatively high degree of baking loss and lower pH of the WGE-enriched breads than those of control bread. Contrary to the mechanical analyses, the sensory properties of the breads were dependent on the WGE type. That is, WGJ-enriched bread showed lower consistency and moistness than control bread, which consequently led to relatively lower overall acceptability. However, WGS addition did not adversely affect the sensory properties of the bread. In particular, addition of 5% WGS somewhat improved the physical and sensory qualities of the bread. Thus, WGE-enriched bread could be produced without loss of bread quality when prepared with 5% WGS.

Incidence of Chronic Pathologic Nephrotoxicity of Cyclosporine A in Pediatric Nephrotic Syndrome (소아 신증후군에서 Cyclosporine A에 의한 만성 조직학적 신독성의 발현빈도에 대한 연구)

  • Kim Ji-Hong;Jeong Hyun-Ju;Choi In-Jun;Kim Pyung-Kil
    • Childhood Kidney Diseases
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    • v.3 no.2
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    • pp.130-144
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    • 1999
  • Purpose : Long-term use of Cyclosporine(CsA) reduce renal blood flow by afferent arteriolar vasoconstriction and lead to chronic pathologic changes of CsA nephrotoxicity - 1) interstitial nephritis(IN); tubular atrophy (TA) and/or interstitial fibrosis(IF),2) arteriolopathy(AP). The Object of this study is to estimate the incidence of chronic pathologic CsA nephrotoxicity by duration of treatment and type of renal disease, relationship between histologic and clinical nephrotoxicity, and optimal duration of CsA therapy. Methods : 102 children with steroid resistant or dependent nephrotic syndrome confirmed by renal biopsy and treated with CsA from 1986 to 1997 were enrolled in this study(58 MCNS, 10 FSGS, 10 MGN, 15 $Henoch-Sch\"{o}nlein$ purpura nephritis with nephrotic syndrome (HSPN) and 9 IgA nephropathy with nephrotic syndrome(IgAN)). CsA was administered for 1yr, 1.5yr, 2yr in 24, 12, 22 MCNS patients and 2, 2, 6 FSGS patients respectively, 1yr, 2yr in MGN and 1yr in HSPN and IgAN. Sequential biopsies were done in all 102 patients after CsA treatment for evaluation of pathologic nephrotoxicity. Results : Complete remission rate was 92.2% (100% in MCNS and MGN, 80% in FSGS, 86.6% in HSPN and 55.5% in IgAN). Incidence of relapse during 6months after CsA treatment was significantly decreased compaed with relapsing spisodes during 6months before CsA treatment in MCNS(P<0.0001) and FSGS(P<0.0001). According to pathologic changes, 71 patients(69.6%) showed no pathological change, 24 patients(23.5%) showed IN and 7 patients(6.8%) showed AP. IN was 16.6%, 33.3%, 27.2% in 1, 1.5, 2 year of CsA treatment group in MCNS. AP was 0%, 16.6%, 9% in 1, 1.5, 2 year of CsA treatment group in MCNS. 14 out of 58 MCNS(24.1%) showed IN and 4 out of 58 MCNS(6.8%) showed AP. Incidence of pathologic change was significantly lower in CsA therapy of <1yr than >1yr(P=0.03). There were no significant difference of incidence of pathologic change in original renal disease, age and sex. Conclusion : Duration of CsA treatment was significant risk factor for nephrotoxicity and optimal duration seemed to be 1 year. Pathologic change due to nephrotoxicity did not correlate with deterioration of renal function and only detectable by renal biopsy.

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