• Title/Summary/Keyword: mediator-less

Search Result 58, Processing Time 0.038 seconds

The Effects of Endothelin Receptor Antagonist on Hemodynamic and Respiratory Mechanics in Experimental Acute Pulmonary Thromboembolism (실험적 급성 폐색전증에서 Endothelin 수용체 길항제가 혈류 및 호흡 역학에 미치는 영향)

  • Lee, Ji-Hyun;Jeon, Yong-Gam;Choe, Kang-Hyeon;Shim, Tae-Sun;Lim, Chae-Man;Koh, Youn-Suck;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong;Lee, Sang-Do
    • Tuberculosis and Respiratory Diseases
    • /
    • v.48 no.2
    • /
    • pp.210-222
    • /
    • 2000
  • Background: Endothelin(ET) is the most potent vasoconstrictor and bronchoconstrictor. The plasma ET-1 level is elevated in patients with acute pulmonary thromboembolism(APTE). This finding suggest that ET-1 may be an important mediator in the cardiopulmonary derangement of APTE. But whether ET-1 is a pathogenic mediator or a simple marker of APTE is not known. The role of ET-1 in the pathogenesis of cardiopulmonary dysfunction in APTE(delete) was investigated through an evaluation of the effects of $ET_A$-receptor antagonist on APTE. The increase in local levels of preproET-1 mRNA and ET-1 peptide in the embolized lung was also demonstrated. Methods: In a canine autologous blood clot pulmonary embolism model, $ET_A$-receptor antagonist(10 mg/kg intravenously, n=6) was administered one hour after the onset of the embolism. Hemodynamic measurements, blood gas tensions and plasma levels of ET-1 immunoreactivity in this treatment group were compared with those in the control group(n=5). After the experiment., preproET-1 mRNA expression(using Northern blot analysis) and the distribution of ET-1(by immunohistochemical analysis) in the lung tissues were examined. Results: The increases in pulmonary arterial pressure and pulmonary vascular resistance of the treatment group were less than those of the control group. Decrease in cardiac output was also less in the treatment group. Complications such as systemic arterial hypotension and hypoxemia did not occur with the administration of $ET_A$-receptor antagonist The plasma level of ET-1 like(ED: what does 'like' mean?) immunoreactivity was increased after embolization in both groups but was significantly higher in the treatment group. The preproET-1 mRNA and ET-1 peptide expressions were increased in the embolized lung. Conclusion: ET-1 synthesis increases with embolization in the lung and may plays play an important role in the pathophysiology of cardiopulmonary derangement of APTE. Furthermore, $ET_A$-receptor antagonist attenuates cardiopulmonary alterations seen in APTE, suggesting a potential benefit of this therapy.

  • PDF

Informative Role of Marketing Activity in Financial Market: Evidence from Analysts' Forecast Dispersion

  • Oh, Yun Kyung
    • Asia Marketing Journal
    • /
    • v.15 no.3
    • /
    • pp.53-77
    • /
    • 2013
  • As advertising and promotions are categorized as operating expenses, managers tend to reduce marketing budget to improve their short term profitability. Gauging the value and accountability of marketing spending is therefore considered as a major research priority in marketing. To respond this call, recent studies have documented that financial market reacts positively to a firm's marketing activity or marketing related outcomes such as brand equity and customer satisfaction. However, prior studies focus on the relation of marketing variable and financial market variables. This study suggests a channel about how marketing activity increases firm valuation. Specifically, we propose that a firm's marketing activity increases the level of the firm's product market information and thereby the dispersion in financial analysts' earnings forecasts decreases. With less uncertainty about the firm's future prospect, the firm's managers and shareholders have less information asymmetry, which reduces the firm's cost of capital and thereby increases the valuation of the firm. To our knowledge, this is the first paper to examine how informational benefits can mediate the effect of marketing activity on firm value. To test whether marketing activity contributes to increase in firm value by mitigating information asymmetry, this study employs a longitudinal data which contains 12,824 firm-year observations with 2,337 distinct firms from 1981 to 2006. Firm value is measured by Tobin's Q and one-year-ahead buy-and-hold abnormal return (BHAR). Following prior literature, dispersion in analysts' earnings forecasts is used as a proxy for the information gap between management and shareholders. For model specification, to identify mediating effect, the three-step regression approach is adopted. All models are estimated using Markov chain Monte Carlo (MCMC) methods to test the statistical significance of the mediating effect. The analysis shows that marketing intensity has a significant negative relationship with dispersion in analysts' earnings forecasts. After including the mediator variable about analyst dispersion, the effect of marketing intensity on firm value drops from 1.199 (p < .01) to 1.130 (p < .01) in Tobin's Q model and the same effect drops from .192 (p < .01) to .188 (p < .01) in BHAR model. The results suggest that analysts' forecast dispersion partially accounts for the positive effect of marketing on firm valuation. Additionally, the same analysis was conducted with an alternative dependent variable (forecast accuracy) and a marketing metric (advertising intensity). The analysis supports the robustness of the main results. In sum, the results provide empirical evidence that marketing activity can increase shareholder value by mitigating problem of information asymmetry in the capital market. The findings have important implications for managers. First, managers should be cognizant of the role of marketing activity in providing information to the financial market as well as to the consumer market. Thus, managers should take into account investors' reaction when they design marketing communication messages for reducing the cost of capital. Second, this study shows a channel on how marketing creates shareholder value and highlights the accountability of marketing. In addition to the direct impact of marketing on firm value, an indirect channel by reducing information asymmetry should be considered. Potentially, marketing managers can justify their spending from the perspective of increasing long-term shareholder value.

  • PDF

Effect of Phenolic Mediators and Humic Acid on the Removal of 1-Indanone Using Manganese Oxide (망간산화물(Birnessite)을 이용한 1- Indanone 제거 시 페놀계 반응매개체와 휴믹산(HA) 영향 평가)

  • Choi, Chan-Kyu;Eom, Won-Suk;Shin, Hyun-Sang
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.34 no.7
    • /
    • pp.445-453
    • /
    • 2012
  • An investigation for removal of 1-indanone (1-ID), which were commonly produced from the biological and/or chemical treatment and natural weathering of the PAHs-contaminated soils, via oxidative transformation mediated by birnessite in the presence of various phenolic mediators is described. This study also examines the potential effect of the natural occurring substance humic acid (HA) on the oxidative transformation. The experiment was carried out in aqueous phase as a batch test (10 mg/L 1-ID, 0.3 mM phenolic mediators, $1.0g/L\;{\delta}-MnO_2$, at pH 5). All of the 11 tested phenoilic mediators belong to the group of natural occurring phenols and are widely used as model constituents of humic substances. From the results of HPLC analysis, it is demonstrated that 1-ID was not reactive to birnessite itself, but it can be effectively removed in birnessite-mediated cross coupling reactions in the presence of the phenolic mediators. The percent removals of 1-ID after 2 day incubation were ranged from 9.2 to 71.2% depending on the phenolic mediators applied. The initial rate constant ($K_{int}$, $hr^{-1}$) values for the 1-ID removals obtained from the pseudo-first-order kinetic plots also widely ranged from 0.18 to 15.0. Results of the correlative analysis between the removal efficiencies and structural characteristics of phenolic mediators indicate that the transformation of the 1-ID was considerably enhanced by the addition of electron-donating substituents (e.g., -OH, $-OCH_3$) at the benzne ring, and much less enhanced by the addition of electron-withdrawing substituents (e.g., -COOH, -CHO). The presence of HA showed that removal efficiencies of 1-ID in the birnessite-phenolic mediator systems decreased with increasing HA concentrations. However at low concentration of HA (< 2 mg/L), it caused some enhancement in the removals of 1-ID as compared to the control.

Effect of Young Chinese's Consuming of Korean Cultural Wave Contents on Their Anti-Korean Sentiment: Focusing the Second-order Mediators of Both Liking for Korean Wave and Positive Perceptions of Koreans (한류콘텐츠 이용정도가 중국인의 혐한정서에 미치는 영향 : 한류호감 한국인에 대한 긍정적 인식의 이차매개효과검증을 중심으로)

  • Lee, Hee-Jin
    • The Journal of the Korea Contents Association
    • /
    • v.17 no.10
    • /
    • pp.394-405
    • /
    • 2017
  • The predominant concern of the study consist of: (1) the effect of young Chinese's consuming of Korean cultural wave contents including Korean TV drama, film, and K-pop on their anti-Korean sentiment; (2) the second-order mediating effects of both liking for Korean wave and positive perceptions of Koreans. The research is based on a survey conducted with 695 chinese people between high-teen and 20's, located in eleven cities of seven provinces. The notable findings are as follow: First, the higher consuming of Korean cultural wave contents, the higher anti-Korean sentiment. Second, young Chinese, consuming more Korean cultural contents, show more liking for Korean wave. The more favor of Korean cultural contents, the more positive perceptions of Koreans. The more liking for Koreans wave contests and the more positive perception of Koreans, the less anti-Korean sentiment. Therefore, it is proved that liking for Korean cultural wave contents and perceiving Koreans with a positive view are important mediator to reduce the anti-Korean sentiment. Some practical implications are discussed based on this study's findings above.

The influences of Phaseolus radiatus L.'s Ethanol Extracts and Fractions on Skin Whitening and Anti-inflammatory Effects (녹두(綠豆) 에탄올 추출물 및 분획물이 피부의 미백, 항염증 효과에 미치는 영향)

  • Lee, Yu-Lim;Choi, Jung-Hwa;Park, Soo-Yeon;Jeong, Min-Yeong;Lee, Ho-Chan;Song, Jie-Hye
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
    • /
    • v.31 no.3
    • /
    • pp.39-49
    • /
    • 2018
  • Objectives : This study is designed to clarify whitening, anti-inflammatory effect of fractions extracted from the mixture of Phaseolus radiatus L. and ethanol. Methods : In this experiment, we were intended to reveal whitening, anti-inflammatory effect of fractions extracted from the mixture of Phaseolus radiatus L. and ethanol. The whitening activity was confirmed by UV blocking activity, tyrosinase inhibiting activity, and melanin formation inhibiting activity. Anti-inflammatory activity is confirmed by measurement of cytotoxicity level by MTT assay and measurement of Cytokine expression, which is the main mediator of inflammation reaction. Results : As a results, overall activity was high in the ethyl acetate fraction. Tyrosinase inhibitory activity was less than 20% at all concentrations, but the activity to inhibit melanin self-production was higher than that of ethyl acetate fraction at $32.19{\pm}2.79%$ at $100{\mu}g/m{\ell}$. And ethyl acetate fraction had a relatively high UV blocking activity. In the anti-inflammatory test, the concentration-dependent activity was shown, and the chloroform and ethyl acetate fractions showed significant NO production inhibitory activity. Cytokine expression was superior to that of the final stage of B cell differentiation, and cell viability was over 80% except for the chloroform fraction at the concentration of $200{\mu}g/m{\ell}$. Conclusions : The results of this experiment confirmed the whitening effect and anti-inflammatory effect of Phaseolus radiatus L.'s extracts and fractions and report the possibility of application as external medicine.

The Influence of PDGF-BB Application Time on the Proliferation of HGF Using Decalcifed Dentin (PDGF-BB 적용시간이 decalcified dentin에서의 치은섬유아세포의 증식에 대한 효과)

  • Park, Jin-Woo;Lee, Jae-Mok;Sun, Jo-Young
    • Journal of Periodontal and Implant Science
    • /
    • v.26 no.4
    • /
    • pp.873-887
    • /
    • 1996
  • Platelet-derived growth factor(PDGF) is one of the polypeptide growth fators. PDGF has been reported as a biological mediator which regulates activities of wound healing process including the cell proliferation, migration and metabolism. Recent studies indicated that demineralized root surface as the primary site for growth factor application has advantages over other application method, especially due to binding capacity of growth factor for exposed matrix component of deminera1ized dentin surface. The purpose of this study is to evaluate optimal application time of PDGF-BB on proliferation of human gingival fibroblasts using deminera1ized dentin surface as primary application site. Human gingival fibroblasts and dentin slabs were prepared from the first premolar tooth extracted for the orthodontic treatment, cells were cultured in DMEM/I0% FBS at the $37^{\circ}C$, 5% CO2 incubator. All of the dentin slabs were preconditioned with Tetracycline HCI(100mg/ml) solution and rinsed in PBS. In the cell proliferation experiment, experimental group was immersed in DMEM containing 10% FBS, 50ng/rnl PDGF-BB during different time(30sec, 1, 2, 4, 8 minutes) and dried. Cells at concentration of $1{\times}10^5$cells/ml were seeded in each culture well which contained dentin slabs and incubated for 6 hours. Then, all of the dentin slabs were moved into new 24 well culture dish and incubated for 24, 48, 72 hours. The cell counting was done by hemocytometer with inverted phase contrast microscope after trypsinization. The results were as follows : The application of PDGF-BB for 1, 2 min slightly increased the number of gingival fibroblasts, and the application of PDGF-BB for 4, 8 min prominently increased the number of gingival fibroblasts. The application of PDGF-BB for 4 min showed maximum proliferation rate of gingival fibroblasts at 24, 48, 72 hours, and the application of PDGF-BB for 8 min showed less proliferation rate of gingival fibroblasts compared to the application of PDGF-BB for 4 min at 24, 48, 72 hours. In conclusion, the application of PDGF-BB for 4 min appeared to be optimal to obtain maximum proliferation of gingival fibroblasts using demineralized dentin surface as primary applicaton site of PDGF-BB.

  • PDF

Pro-(IL-18) and Anti-(IL-10) Inflammatory Promoter Genetic Variants (Intrinsic Factors) with Tobacco Exposure (Extrinsic Factors) May Influence Susceptibility and Severity of Prostate Carcinoma: A Prospective Study

  • Dwivedi, Shailendra;Singh, Sarvesh;Goel, Apul;Khattri, Sanjay;Mandhani, Anil;Sharma, Praveen;Misra, Sanjeev;Pant, Kamlesh Kumar
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.8
    • /
    • pp.3173-3181
    • /
    • 2015
  • Background: It has been hypothesized that IL-18 (pro-) and IL-10 (anti-) inflammatory genetic variants at -607 C/A-137G/C and -819C/T,-592C/A, respectively, may generate susceptibility and severity risk with various modes of tobacco exposure in prostate carcinoma (PCa) patients. IL-18 is a pro-inflammatory cytokine expressed on various cells including prostate gland elements, and is a key mediator of immune responses with anti-cancerous properties. IL-10 is an anti-inflammatory cytokine that is associated with tumour malignancy which causes immune escape. Materials and Methods: The present study was conducted with 540 subjects, comprising 269 prostate carcinoma patients and 271 controls. Genotyping was performed by PCR-RFLP and confirmed by real time PCR probe-based methods. Results: The findings indicated that the mutant heterozygous and homozygous genotype CC and GC+CC showed significant negative associations (p=0.01, OR=0.21; 95% CI: 0.08-0.51 and p=0.011, OR=0.43; 95% CI: 0.22-0.81, respectively) thus, less chance to be diagnosed as cancer against GG genotype of tobacco smoking patients. In addition, a heterozygous GC genotype at the same locus of IL-18 pro-inflammatory cytokine may aggravate the severity (OR=2.82; 95%CI 1.09-7.29 :p=001) so that patients are more likely to be diagnosed in advanced stage than with the GG wild homozygous genotype. Our results also illustrated that anti-inflammatory cytokine (IL-10) genetic variants, although showing no significant association with susceptibility to cancer of the prostate, may gave profound effects on severity of the disease, as -819 TC (OR=4.60; 95%CI 1.35-15.73), and -592 AC (OR=5.04; 95%CI 1.08-25.43) of IL-10 in tobacco chewers and combined users (both chewers and smokers) respectively, are associated with diagnosis in more advanced stage than with other variants. Conclusions: We conclude that promoter genetic variants of IL-18 and IL-10 with various modes of tobacco exposure may affect not only susceptibility risk but also severity in prostate cancer.

Inhibition of Human Neutrophil Elastase by Tetracyclines and Mechanism of the Inhibition (Tetracycline계 항균제에 의한 호중구 Elastase의 효소 활성도 억제 및 그 작용 기전)

  • Kim, Woo-Mi;Kang, Koo-Il
    • The Korean Journal of Pharmacology
    • /
    • v.29 no.1
    • /
    • pp.131-137
    • /
    • 1993
  • Human neutrophil elastase (HNE, EC 3,4,21, 11), a mediator of tissue breakdown, was inhibited by tetracycline, oxytetracycline and demeclocycline. Among them, oxytetracycline showed the most potent inhibitory effect on the activity of HNE. IC50 of this drug at our specific condition was less than 1 mM. Tetracycline inhibited human neutrophil elastase non-competitively, and oxytetracycline inhibited competitively. Ki values of tetracycline and oxytetracycline were 4.9 mM and 0.39 mM, respectively. Structural modified tetracycline, de-dimethylaminotetracycline, which showed no antibiotic activity since the active dimethylamino radical was removed from the position #4 of the tetracycline, showed similar inhibition effect on the activity of human neutrophil elastase to that of tetracycline. Thus, we speculated that inhibition of human neutrophil elastase by tetracyclines was not depended on the dimethylamino radical which is a critical active site for antibiotic effect, rather it was depended on the hydoxyl radical of tetracyclines. Therefore, the property of inhibiting elastase may be an additional molecular biochemical mechanism of action of these drugs at the inflammatory sites.

  • PDF

Human and Animal Disease Biomarkers and Biomonitoring of Deoxynivalenol and Related Fungal Metabolites as Cereal and Feed Contaminants (곡물 및 사료오염 데옥시니발레놀 및 대사체에 의한 인축질환 연계 생체지표 및 바이오모니터링)

  • Moon, Yuseok;Kim, Dongwook
    • Journal of Food Hygiene and Safety
    • /
    • v.29 no.2
    • /
    • pp.85-91
    • /
    • 2014
  • Deoxynivalenol (DON) and related trichothecene mycotoxins are extensively distributed in the cereal-based food and feed stuffs worldwide. Recent climate changes and global grain trade increased chance of exposure to more DON and related toxic metabolites in poorly managed production systems. Monitoring the biological and environmental exposures to the toxins are crucial in protecting human and animals from toxicities of the hazardous contaminants in food or feeds. Exposure biomarkers including urine DON itself are prone to shift to less harmful metabolites by intestinal microbiota and liver metabolic enzymes. De-epoxyfication of DON by gut microbes such as Eubacterium strain BBSH 797 and Eubacterium sp. DSM 11798 leads to more fecal secretion of DOM-1. By contrast, most of plant-derived DON-glucoside is also easily catabolized to free DON by gut microbes, which produces more burden to body. Phase 2 hepatic metabolism also contributes to the glucuronidation of DON, which can be useful urine biomarkers. However, chemical modification could be very typical depending on the anthropologic or genetic background, luminal bacteria, and hepatic metabolic enzyme susceptibility to the toxins in the diet. After toxin exposure, effect biomarkers are also important in estimating the linkage and mechanisms of foodborne diseases in human and animal population. Most prominent adverse effects are demonstrated in the DON-induced immunological and behavioral disorders. For instance, acutely elevated interleukin-8 from insulted gut exposed to dietaty DON is a dominant clinical biomarker in human and animals. Moreover, subchronic exposure to the toxins is associated with high levels of serum IgA, a biological mediator of IgA nephritis. In particular, anorexia monitoring using mouse models are recently developed to monitor the biological activities of DON-induced feed refusal. It is also mechanistically linked to alteration of serotoin and peptide YY, which are promising biomarkers of neurological disorders by the toxins. As animal-alternative biomonitoring, huamn enterocyte-based assay has been developed and more realistic gut mimetic models would be useful in monitoring the effect biomarkers in resposne to toxic contaminants in the future investigations.

Development of electrochemical biosensor for determination of galactose (4갈락토오즈 측정을 위한 전기화학적 바이오센서 개발)

  • Park, Kap Soo;Cho, Soon Sam;Quan, De;Lee, Jae Seon;Cha, Geun Sig;Nam, Hakhyun
    • Analytical Science and Technology
    • /
    • v.20 no.5
    • /
    • pp.393-399
    • /
    • 2007
  • In principle, the blood galactose level may be determined conveniently with a strip-type biosensor similar to that for glucose. In this study, we describe the development of a disposable galactose biosensor strip for point-of-care testing. The sensor strip is constructed with screen-printed carbon paste electrode (SPCE) and sample amount (< $100{\mu}L$). The developed strip the galactose level in less than 90 s using bienzymatic system of galactose oxidase (GAO) and horseradish peroxidase (HRP). The effects of pH, mediator (1,1-ferrocenedimethanol) concentration, ratio of enzymes, and applied potential were determined preliminarily with glassy carbon electrodes, and optimized further with the strip-type electrodes. The sensor exhibits linear response in the range of $0{\sim}400{\mu}M$ ($r^2$ = 0.997, S/N = 3). Since a low working potential, in principle, the fabricated disposable galactose biosensor has -100 mV (vs. Ag/AgCl), it is applied for the detection of galactose, interfering responses from common interferents such as ascorbic acid, uric acid and acetaminophen could be minimized. The sensor has been used to determine the total galactose level in standard samples with satisfactory reproducibility (CV = 5 %).