• Title/Summary/Keyword: time-dependent effect

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Protective Effect of 3,5-Dicaffeoylquinic Acid Isolated from Ligularia fischeri against Oxidative Damage in HepG2 Cells (HepG2 세포에서 산화적 손상에 대한 곰취 유래 3,5-Dicaffeoylquinic Acid의 보호 효과)

  • Park, Sun-Young;Kim, Gur-Yoo;Jhoo, Jin-Woo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.11
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    • pp.1286-1292
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    • 2017
  • This study was conducted to investigate the hepatoprotective effects of 3,5-dicaffeoylquinic acid (3,5-DCQA) isolated from Ligularia fischeri against hydrogen peroxide-induced oxidative stress in HepG2 cells. Antioxidative effects of 3,5-DCQA were determined by measuring antioxidant enzyme [superoxide dismutase (SOD), catalase (CAT) glutathione peroxidase (GPx)] expression levels against hydrogen peroxide-induced oxidative stress using real-time PCR analysis. 3,5-DCQA treatment significantly increased gene expression levels of SOD, CAT, and GPx in a dose-dependent manner ($10{\sim}30{\mu}g/mL$) in HepG2 cells. Hepatoprotective effects were analyzed by measuring glutamic oxaloacetic transaminase (GOT), lactate dehydrogenase (LDH), and gamma-glutamyl transferase (GGT) activities using a biochemistry analyzer in hydrogen peroxide-treated HepG2 cells. 3,5-DCQA treatment significantly reduced GOT, LDH, and GGT activities in a dose-dependent manner ($10{\sim}30{\mu}g/mL$) against increased liver function index enzyme activities induced by hydrogen peroxide oxidative stress in HepG2 cells. The results reveal that 3,5-DCQA compound isolated from Ligularia fischeri can be useful for the development of an effective hepatoprotective agent.

Effect of Cold Exposure on Thyroid Thermogenesis in Rats (한냉에 노출된 흰쥐에서 갑상선 호르몬이 체열 생산인 미치는 영향)

  • 황애란
    • Journal of Korean Academy of Nursing
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    • v.13 no.2
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    • pp.87-104
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    • 1983
  • It has been well documented that animals exposed to cold show increased activity of thyroid gland. The calorigenic action of thyroid hormone has been demonstrated by a variety of in vivo and in vitro studies. According to Edelman et al., the thyroid thermogenesis is due to activation of energy consuming processes, especially the active sodium transport by the hormone in target tissues. If so, the increase in thyroid activity during cold exposure should induce increased capacity of sodium transport in target tissue and the change in tissue metabolism should be precisely correlated with the change in Na+_K+_ATPase activity of the tissue. This possibility was tested in the present study: in one series, changes in oxygen consumption and Na+_K+_-ATPase activity of liver preparations were measured in rats as a function of thyroid status, in order to establish the effect of thyroid hormone on the tissue respiration and enzyme system in another series, the effect of cold stimulus on the serum thyroid hormone level, hepatic tissue oxygen consumption and Na+_K+_ATPase activity in rats. The results obtained are as follows: 1. The Na+_dependent oxygen consumption of liver slices, the oxygen consumption of liver mitochondria and the Na+_K+_ATPase activity of liver preparations were significantly inhibited in hypothyroidism and activated in hyperthyroidism. Kinetic analysis indicated that the Vmax. of Na+_K+_ATPase was decreased in hypothyroidism and increased in hyperth)'roidism. 2. In cold exposed rats, the serum triiodothyronine (T₃) level increased rapidly during the initial one day of cold exposure, then declined slowly to the control level after two weeks. The serum thyroxine (T₄) level decreased gradually throughout the cold exposure. Accordingly the T₃/T₄ratio increased. The mitochondrial oxygen consumption and the Na+_dependent oxygen consumption of liver slices increased during the first two days and then remained unchanged thereafter The activity of the Na+_K+_ATPase in liver preparations increased during cold exposure with a time course similar to that of oxygen consumption. Kinetic analysis indicated that the Vmax. of Na+_K+_ATPase increased. 3. Once the animal was adapted to cold, induction of hypothyroidism did not significantly alter the hepatic oxygen consumption and Na+_K+_ATPase activity. These results indicate that: 1) thyroid hormone increases capacities of mitochondrial respiration and active sodium transport in target tissues such as liver; 2) the increased T₃level during the initial period of cold exposure facilitates biosynthesis of Na+_K+_ATPase and mitochondrial enzymes for oxidative phosphorylation, leading to enhanced production and utilization of ATP, hence heat production.

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Cytoprotective Effect of Zinc-Mediated Antioxidant Gene Expression on Cortisol-Induced Cytotoxicity (Cortisol 유발 세포독성에 대한 아연 관련 항산화 유전자 발현 증가에 의한 세포보호 효과)

  • Chung, Mi Ja;Kim, Sung Hyun;Hwang, In Min
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.5
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    • pp.649-656
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    • 2015
  • The protective effect of zinc against cortisol-induced cell injury was examined in rainbow trout gill epithelial cells. Cells exposed to cortisol for 24 h showed increased leakage of lactate dehydrogenase (LDH) as well as decreased cell viability in a dose-dependent manner. Treatment with zinc ($100{\mu}M$ $ZnSO_4$) reduced the severity of both LDH release and cell death as well as protected cells against cortisol-induced caspase-3 activation, indicating reduction of apoptosis. Cortisol-induced cell death, leakage of LDH, and caspase-3 activation were blocked by the glucocorticoid receptor antagonist Mifepristone (RU-486), suggesting that cell injury was cortisol-dependent. In addition, we studied the effect of zinc on the expression of antioxidant genes such as metallothionein A (MTA), metallothionein B (MTB), glutathione-S-transferase (GST), and glucose-6-phosphate dehydrogenase (G6PD) during cortisol-induced cell injury. MTA, MTB, GST, and G6PD mRNA levels increased after treatment with zinc or cortisol, separately or in combination. Higher mRNA levels of MTA, MTB, GST, and G6PD were detected when cells were treated with $100{\mu}M$ $ZnSO_4$ and $1{\mu}M$ cortisol in combination at the same time compared to treatment with zinc or cortisol separately. Cells treated with zinc showed increased intracellular free zinc concentrations, and this response was significantly enhanced in cells treated with cortisol and zinc. In conclusion, zinc treatment inhibited cortisol-induced cytotoxicity and apoptosis through indirect antioxidant action.

The Effects of Advanced Design Innovation Strategy on Business Performance (선행 디자인 혁신 전략이 기업 성과에 미치는 영향)

  • Kim, Yong-Wook;Song, In-Am;Hwang, Hee-Joong
    • Journal of Distribution Science
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    • v.11 no.10
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    • pp.27-36
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    • 2013
  • Purpose - This paper empirically studies the effects of advanced design innovation strategy on business performance, to investigate manufacturing industries that can develop design-driven-innovation strategies. Many researchers now recognize the importance of design in a CEO's decision-making process. To analyze these effects, this study deduces the definition of advanced design strategy by reviewing existing studies. The advanced design is a strategy that is applied to improve business performance instead of the appearance of a product for increasing its sales. In terms of business processes, the advanced design strategy is defined as the incorporation of business activities prior to the development of the product, to offer new experiences and values to users, from those designs. Research design/data/methodology - This paper establishes a model for empirical analysis. In this study, we derived factors of the characteristics of advanced design based on previous studies. We tried to investigate whether advanced design innovation strategy and entrepreneur's characteristics could have any impact on business performance. At the same time, we tried to find out the moderating effect of entrepreneurs' characteristics. The advanced design is made up of three elements: precedence, integration, and immersion of design activities. These three elements are independent variables for the model. The dependent variables are: increased rate of sales, R & D performance, and public image of the company. Specifically, this study establishes a CEO's characteristics as a moderating variable between the independent and dependent variables. Results - We proved that the level of entrepreneurs' characteristics has a moderating effect on the business performance. The findings of this study offer the following theoretical implications. The precedence of design activities positively affects the increased rate of sales by offering new experiences to users and creating new values. The integration of design activities also has a positive effect on the R&D performance. In addition, the immersion of design activities positively influences all the elements comprising business performance. The analysis of moderating variables elucidates that CEO's characteristics have a moderating role between precedence, integration, and immersion of design activities, and business performance. Conclusions - The practical implications of the study are as follows. This study contributes to the progression of advance design theories by conducting an empirical study on the advanced design concept. More importantly, the empirical study on the CEO group seeking exploratory innovation supports Verganti's "design-driven innovation" concept, according to which design can make innovation successful by offering useful values to users, as evident in the case of many innovative companies, such as Nintendo and Apple. Future studies need to investigate the reliability of practical examples, including the various activities of business. We suppose that there may be real differences between the results of this study and the applicative situation in the presence of a CEO group.

Influence of Ketamine on Catecholamine Secretion in the Perfused Rat Adrenal Medulla

  • Ko, Young-Yeob;Jeong, Yong-Hoon;Lim, Dong-Yoon
    • The Korean Journal of Physiology and Pharmacology
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    • v.12 no.3
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    • pp.101-109
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    • 2008
  • The aim of the present study was to examine the effects of ketamine, a dissociative anesthetics, on secretion of catecholamines (CA) secretion evoked by cholinergic stimulation from the perfused model of the isolated rat adrenal gland, and to establish its mechanism of action, and to compare ketamine effect with that of thiopental sodium, which is one of intravenous barbiturate anesthetics. Ketamine ($30{\sim}300{\mu}M$), perfused into an adrenal vein for 60 min, dose- and time-dependently inhibited the CA secretory responses evoked by ACh (5.32 mM), high $K^+$ (a direct membrane-depolarizer, 56 mM), DMPP (a selective neuronal nicotinic NN receptor agonist, $100{\mu}M$) and McN-A-343 (a selective muscarinic M1 receptor agonist, $100{\mu}M$). Also, in the presence of ketamine ($100{\mu}M$), the CA secretory responses evoked by veratridine (a voltage-dependent $Na^+$ channel activator, $100{\mu}M$), Bay-K-8644 (an L-type dihydropyridine $Ca^{2+}$ channel activator, $10{\mu}M$), and cyclopiazonic acid (a cytoplasmic $Ca^{2+}$-ATPase inhibitor, $10{\mu}M$) were significantly reduced, respectively. Interestingly, thiopental sodium ($100{\mu}M$) also caused the inhibitory effects on the CA secretory responses evoked by ACh, high $K^+$, DMPP, McN-A-343, veratridine, Bay-K-8644, and cyclopiazonic acid. Collectively, these experimental results demonstrate that ketamine inhibits the CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors and the membrane depolarization from the isolated perfused rat adrenal gland. It seems likely that the inhibitory effect of ketamine is mediated by blocking the influx of both $Ca^{2+}$ and $Na^+$ through voltage-dependent $Ca^{2+}$ and $Na^+$ channels into the rat adrenal medullary chromaffin cells as well as by inhibiting $Ca^{2+}$ release from the cytoplasmic calcium store, which are relevant to the blockade of cholinergic receptors. It is also thought that, on the basis of concentrations, ketamine causes similar inhibitory effect with thiopental in the CA secretion from the perfused rat adrenal medulla.

Mechanisms of Insulinotropic Effect of YHB-2017 [Genistein] Isolated from fermentation Broths of Streptomyces sp. (방선균에서 유래한 YHB-2017 [Genistein]의 인슐린 분비 촉진 작용 기전)

  • Kwag, Won-Jae;Park, You-Hoi;Park, Jun-Chul;Lee, Byung-Kyu;Kang, Yup;Choe, Tae-Boo
    • KSBB Journal
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    • v.21 no.6 s.101
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    • pp.466-473
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    • 2006
  • Impaired insulin secretion from pancreatic beta-cells in response to glucose is an important feature in the pathology of non-insulin-dependent diabetes mellitus (NIDDM). In the course of screening for useful insulin secretagogues, we have isolated and identified YHB-2017 (Genistein) as a insulin secretion potentiator from fermentation broths of our in-house microbial library. The insulinotropic activity of YHB-2017 in isolated rat pancreatic islets was exerted only at high concentration of glucose (8.3-16 mM) but not at low concentration of glucose (3.3-5.5 mM). Also, in perifusion study with isolated rat pancreatic islets, YHB-2017 stimulated insulin secretion in a time-dependent manner when YHB-2017 was added to KRB buffer containing 16 mM glucose. In the presence of $200\;{\mu}M$ diazoxide and 35 mM KCI, which stimulates maximum $Ca^{2+}$ influx independently of KATP channel, YHB-2017 enhanced KATP channel-independent insulin secretion at high concentration glucose (16 mM). To elucidate the mechanisms of the glucose-dependent potentiation effect of YHB-2017, pharmacologic inhibitors for protein kinase A, protein kinase C and calcium/calmodulin kinase II were pre-treated and then the potentiation effect of YHB-2017 on insulin secretion was investigated. Pre-treatment of H89 as a PKA inhibitor had a significant inhibitory effect on YHB-2017-induced potentiation effect. Furthermore, western immunoblotting analyses revealed that YHB-2017 increased phosphorylation of PKA substrates and cAMP response element-binding protein (CREB) under high concentration of glucose. These results demonstrated that the insulinotropic effect of YHB-2017 is mediated through PKA signal pathway and activated amplifying $K_{ATP}$ channel-independent insulin secretion pathway.

Effect of Korean Mistletoe Extract M11C (Non-lectin Components) on the $TNF-\alpha$ Expression and Secretion from Human Peripheral Blood Monocytes (한국산 겨우살이 추출물 M11C (렉틴 구성물질)가 단구세포의 $TNF-\alpha$ 유전자 발현유도 및 분비에 미치는 효과)

  • Jun, Myung-Ha;Kang, Tae-Bong;Chang, Sung-Ho;Choi, Wahn-Soo;Seong, Nak-Sul;Her, Erk
    • Korean Journal of Medicinal Crop Science
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    • v.15 no.1
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    • pp.30-37
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    • 2007
  • It is well-known that Korean mistletoe (Viscum album) extract has an immune activity and anticancer effect. In this study, Korean mistletoe extract, M11C (non-lectin components), was used to examine whether this extract might activate human peripheral monocyte to produce tumor necrosis $factor-\alpha$ $(TNF-\alpha)$. To examine the effect of M11C on the production of $TNF-\alpha$ from monocyte, the monocyte were stimulated by the M11C, and then collected the supernatant (M11C stimulated monocyte-conditioned media; MCM). MCM was treated to the $TNF-\alpha$ sensitive L929 cells, and then L929 cytotoxicity was measured by means of MTT. MCM had cytotoxic effect on L929. And the cytotoxic effect of MCM on L929 was almost abolished by $anti-TNF-\alpha$ antibody. These data indicated that MCM contained $TNF-\alpha$, suggesting the $TNF-\alpha$ generation from M11C-stimulated monocyte. This suggestion was confirmed from the data that $TNF-\alpha$ was highly detected in MCM by immunoblotting technique. M11C effect on $TNF-\alpha$ production from monocyte was in the dose and stimulating time dependent manners. Also the effect of M11C on the expression of $TNF-\alpha$ mRNA from monocyte was shown in the dose and stimulating time dependent manners. As a result, Korean mistletoe extract, M11C, could be used for an immunostimulator.

Effects of Curcuma longa L.on Human Stomach Cancer Cells (울금(鬱金)이 위암세포(胃癌細胞)에 미치는 영향(影響))

  • Cho, Yu-Kyung;Yoon, Song-Ryub;Kim, Beong-Woo;Kim, Jin-Sung;Ryu, Ki-Won;Ryu, Bong-Ha
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.9 no.1
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    • pp.15-37
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    • 2003
  • Objective: We are aimed to identify anti-tumor effects of Curcuma longa L. on the stomach cancer cells through molecular biologic methods. Material & Methods: We used AGS as human stomach cancer cells obtained from American Type Culture Collection. The boiled extract of Curcuma longa L. $5{\mu}l$ (Sample I), $10{\mu}l$ (Sample II) was treated to cultural media(ml) for 0, 6, 12, 24, 48 hours. We measured the killing effect on stomach cancer cells through Trypan blue exclusion test and the suppressive effect on viability of stomach cancer cells via MTT assay. For identification of its anticancer mechanism, the revelation of Bcl-2, Bcl-XL, and Bax which are genes related to apoptosis using the quantitative RT-PCR, change of mitochondria membrane permeability and membrane potential via flow cytometry, the cycle of cell mitosis, caspase cleavage and annexin V staining were examined. Results: 1. showed significant killing effect on stomach cancer cell than the control group with a time(6 hours later) and density dependent manner, which was statistical significance. 2. Extract of Curcuma longa L. showed suppressive effect on viability of stomach cancer cells that each test groups had more suppressive effects on viability of stomach cancer cells than the control group with a time(6 hours later), which was statistical significance.(p<0.05) 3. In the test about the revelation of genes related to apoptosis, the revelation of Bcl-2 and Bcl-XL decreased with a density manner which was statistical significance. but the revelation of Bax was not changed with statistical significance. 4. Extract of Curcuma longa L. caused apoptosis by decreasing the absorbance of mitochondria with statistical significance, and also induced apoptosis by decreasing the membrane potential of mitochondria. 5. Extract of Curcuma longa L. destructed the cell cycle of cell mitosos. 6. Cell apoptosis was induced by extract of Curcuma longa L. certificated by method of caspase cleavage and annexin V staining. Conclusion: This experiment showed that Curcuma longa L. has anti-tumor effect with statistical significance. This is in vitro experiment and basic experiment on Curcuma longa L.. We hope more progressive research on Curcuma longa L. will go on and its anti-tumor effects will be more practically identified.

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A Study on the Spatial Accessibility to the Psychiatry Department in General Hospital and Its Relationship with the Visit of Mental Patients (종합병원 정신건강의학과에 대한 공간적 접근성과 외래 의료이용 분석)

  • Dong, Jae Yong;Lee, Kwang-Soo
    • Health Policy and Management
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    • v.27 no.4
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    • pp.315-323
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    • 2017
  • Background: This study was purposed to analyze the effect of spatial accessibility to the psychiatry department in general hospital on the outpatient visit of mental patients. Methods: Data was provided from the Statistics Korea and Statistical Geographic Information Service, National Health Insurance Service, Health Insurance Review and Assessment Service, and Korea Transport Institute in 2015. The study regions were 103 administrative regions such as Si and Gu. The 103 regions had at least one general hospitals with a psychiatry department. The number of outpatient visit of mental patients in regions was used as the dependent variable. Spatial accessibility to mental general hospital was used as the independent variable. Control variables included such as demographic, economic, and health medical factors. This study used network analysis and multi-variate regression analysis. Network analysis by ArcGIS ver. 10.0 (ESRI, Redlands, CA, USA) was used to evaluate the average travel time and travel distance in Korea. Multi-variate regression analysis was conducted by SAS ver. 9.4 (SAS Institute Inc., Cary, NC, USA). Results: Travel distance and time had significant effects on the number of outpatient visits in mental patients in general hospital. Average travel time and travel distance had negative effects on the number of visits. Variables such as (number of total population, percentage of aged population over 65, and number of mental general hospital) had significant effects on the number of visit in mental patients. Conclusion: Health policy makers will need to consider the spatial accessibility to the mental healthcare organization in conducting regional health planning.

Synthesis of C3S, C2S, C3A Powders using Ultra-fine Calcium Oxide Powder Synthesized from Eggshell and Effect of C3A Content on Hardened Mixed Aggregates (난각으로부터 합성된 초미립 CaO 분말을 이용한 C3S, C2S, C3A 분말 합성 및 혼합 경화체에 미치는 C3A 함량의 영향)

  • Kong, Heon;Kwon, Ki-Beom;Park, Sang-Jin;Noh, Whyo-Sub;Lee, Sang-Jin
    • Journal of Powder Materials
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    • v.26 no.6
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    • pp.493-501
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    • 2019
  • In this work, ultra-fine calcium oxide (CaO) powder derived from eggshells is used as the starting material to synthesize mineral trioxide aggregate (MTA). The prepared CaO powder is confirmed to have an average particle size of 500 nm. MTAs are synthesized with three types of fine CaO-based powders, namely, tricalcium silicate (C3S), dicalcium silicate (C2S), and tricalcium aluminate (C3A). The synthesis behavior of C3S, C2S and C3A with ultra-fine CaO powder and the effects of C3A content and curing time on the properties of MTA are investigated. The characteristics of the synthesized MTA powders are examined by X-ray diffraction (XRD), field emission-scanning electron microscope (FE-SEM), and a universal testing machine (UTM). The microstructure and compressive strength characteristics of the synthesized MTA powders are strongly dependent on the C3A wt.% and curing time. Furthermore, MTA with 5 wt.% C3A is found to increase the compressive strength and shorten the curing time.