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Effect of Genistein and Daidzein on Glucose Uptake in Isolated Rat Adipocytes; Comparison with Respective Glycones

  • Choi, Myung-Sook;Jung, Un-Ju;Kim, Myung-Joo;Kim, Jong-Yeon;Park, So-Young;Jang, Joo-Yeum;Lee, Mi-Kyung
    • Preventive Nutrition and Food Science
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    • v.10 no.1
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    • pp.52-57
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    • 2005
  • Soy and soy foods are a rich source of isoflavones, which possess several biological activities. The effect of soy isoflavones, genistin and diadzin and their respective aglycones, on glucose uptake in adipocytes isolated from normal or high-fat fed rats was examined. As expected, insulin stimulated glucose uptake in a concentration-dependent manner. However, genistin and daidzin and their aglycones inhibited glucose uptake in a concentration-dependent (25-100μM) manner. In a time-course response, the aglycones significantly inhibited glucose uptake throughout 3 hr (after 30, 60, 120, 180 min), whereas the glycones only significantly inhibited the glucose uptake after 120 min and 180 min in the isolated rat adipocytes. Thus, the glucosides of genistein and daidzein, i.e. genistin and daidzin, were much less effective in inhibiting glucose uptake than their aglycones. In addition, genistin and daidzin did not significantly affect the insulin-stimulated glucose uptake, whereas genistein and daidzein did significantly inhibited glucose uptake compared to the vehicle control group by 47.5% and 24.8%, respectively (p < 0.05). The isoflavones also significantly inhibited glucose uptake in adipocytes isolated from rats fed a high-fat diet (50% of total calorie intake) when compared to the vehicle control. Finally, the isoflavones were found to enhance lipolysis in adipocytes isolated from high-fat fed rats, where the glycerol released by the aglycones was also higher than that released by the glycones. The current results showed that the inhibitory effect of daidzein on glucose uptake was very similar to that of genistein. The aglycones were more potent in inhibiting the uptake of glucose and a more potent stimulator of lypolysis than the glycones in adipocytes isolated from high-fat fed rats.

Growth and Chlorophyll Biosynthesis of Vigna angularis under Lead Stress

  • Suh-Young Koo;Sun
    • Journal of Environmental Science International
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    • v.1 no.2
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    • pp.145-155
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    • 1992
  • The effect of various supplies of lead singly and in combination with aluminium on growth and chlorophyll biosynthesis was investigated in 7-day-old Vigna anguluris seedlings. Expose to 50 $\mu$N Pb or more drastically reduced root elongation rate. Significant depressions in root growth was observed within 1 day and no recovery of growth was seen over the duration of treatment period. Root elongation decreased depending on the Pb concentrations. Root growth inhibition was stronger than shoot growth inhibition. The initiation of lateral roots appeared to be more sensitive to Pb than the growth of main roots. Inhibition of root and shoot elongation by Pb was lessened by combined exposure of Pb and Al, suggesting that the presence of AA reverse the inhibitory effect of Pb alone. With the histochemical sodium rhodizonate method the rate of Pb uptake was dependent on the Pb concentration and exposure time of the roots to Pb salts. Pb was first deposited on the root surface and then translocated radially in the root cap cells. During a longer Pb administration (up to 72 h) Pb penetration was nonuniform, with accumulation within the cortex or endodermis. There was drastic reduction in chlorophyll content by Pb. The Pb inhibition of chlorophyll synthesis was concentration dependent. 5-Aminolevulinic acid dehydratase (ALAD) activity exhibited distinct inhibition from control. Reduction in chlorophyll content was accompanied by proportional changes in ALAD activity. Chlorophyll content and ALAD activity were less affected by combined exposure of Pb and Al, suggesting that Al has a protective effect against the inhibiting action of Pb on photosynthetic activity.

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Drying Characteristics and Drying Model of Red Pepper (고추의 건조특성(乾燥特性)과 건조모델에 관(關)한 연구(硏究))

  • Cho, Y.J.;Koh, H.K.
    • Journal of Biosystems Engineering
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    • v.11 no.1
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    • pp.52-63
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    • 1986
  • This study was performed to find out drying characteristics and develop drying model for the design of an efficient dryer or drying system of red peper. The basic model which describes drying phenomenon of red pepper was firstly established, and drying tests were conducted at 14-different drying conditions. In this test, the effects of drying air temperature and relative humidity on the rate of drying were undertaken. Finally, a new drying model based on these experimental results was developed to describe the drying characteristics of red pepper. The results from this study may be summarized as follows. 1. Drying constant of the basic model established from Lewis' experimental model and diffusion equation was theoretically deduced as a function of moisture content and inner-temperature of red pepper. 2. From the results of drying tests, drying air temperature was found to have the greatest effect on the rate of drying. However, the effect of temperature was small for the condition of high relative humidity, and for low temperature, the effect of relative humidity was found to be large even though the range of relative humidity was low. 3. Modified Henderson equation was found to be better than Chung equation as the EMC model for the estimation of the equilibrium moisture content of red Pepper. 4. Constant-rate drying period did not exist in the red pepper drying test. And falling-rate drying period was divided into three distinct phases. Drying rate was dependent on the moisture content, the inner-temperature of red pepper and the change of physical property due to drying. 5. Drying constant increased with decrease of free moisture content, but it decreased at the end of the drying period. Also, drying constant was dependent on the drying air temperature and relative humidity. 6. The new drying model developed in this study was found to be most suitable in describing the drying characteristics of red pepper. Therefore, it may be concluded that drying time could be accurately estimated by the new drying model.

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The Effects of Orostachys Japonicus A. Berger Aquacupuncture on Cell Death and DNA Damage Induced by H2O2 in Renal Tubular Cell (와송약침액(瓦松藥鍼液)이 신장세포(腎臟細胞)에서 H2O2에 의한 세포사망(細胞死亡) 및 DNA 손상(損傷)에 미치는 영향(影響))

  • Park, Sang-Won;Song, Choon-Ho
    • Journal of Acupuncture Research
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    • v.18 no.1
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    • pp.88-99
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    • 2001
  • Objectives : This study was performed to determine if Orostachys japonicus A. Berger aquacupuncture (OjB) provides the protective effect against the loss of celi viability and DNA damage induced by oxidant in renal proximal tubular cells. Methods : The cell viability was evaluated by a MTT reduction assay and DNA damage was estimated by measuring double stranded DNA breaks in opossum kidney (OK) cells, an established proximal tubular cell line. Lipid peroxidation was determined by measuring malondialdehyde (MDA), a product of lipid peroxidation. Results : $H_2O_2$ increased the loss of cell viability in a time-dependent manner, which were prevented by 0.1% OjB. The protective effect of OjB was dose-dependent over concentration range of 0.05-0.5%. $H_2O_2$ caused ATP depletion and DNA damage, which were prevented by OjB and the hydrogen peroxide scavenger catalase. The loss of cell viability by $H_2O_2$ was not affected by the antioxidant DPPD, but lipid peroxidation by the oxidant was completely inhibited by DPPD. Conclusions : These data suggest that $H_2O_2$-induced death results from a lipid peroxidation-independent mechanism and the protective effect of OjB is not associated with its antioxidant activity.

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Effect of High glucose on JNK/ERK signaling pathway in UMR106 cells

  • Jung, In-Ok;Jin, Mei-Hua;Kim, Sung-Jin
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2003.11a
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    • pp.79-79
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    • 2003
  • Recently diabetes has been found to be associated with metabolic bone diseases such as osteoporosis. In the present study, attempts have been made-to explore the effect of high glucose in bone formation. Osteoblast-like UMR 106 cells were treated with high glucose (22mM, 33mM, 44mM) for 1 or 2 days. High glucose significantly inhibited proliferation of UMR106 cells in a time- and dose- dependent manner as evidenced by MTT assay. For the evaluation of collagen synthesis, UMR 106 cells were cultured in high glucose media (44mM) for 24 h and the ratio of collagen content to total protein was measured. In addition, gene expression pattern of type I collagen was assessed by RT-PCR. The high concentration of glucose inhibited a collagen synthesis, a marker of bone formation activity. JNK, c- Jun N-terminal Kinase, is known to play an important role in stress-associated cell death. In this regard, we tested to determine whether high glucose has any effect on JNK activity. It has been found that treatment of high glucose induced phosphorylation of JNK. On the other hand, ERK phosphorylation was inhibited by high glucose in a dose-dependent manner. Taken together, Therefore these results indicate that inhibition of proliferation in UMR 106 cells following high glucose is related to JNK/ERK containing signal pathways. This study showed high glucose concentration could alter the bone metabolism leading to defective bone formation, suggesting that high glucose due to diabetes may playa significant role in the development of metabolic bone disease.

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Vitamin C Enhances the Effect of Etoposide to Inhibit Human Prostate Cancer Growth in vitro (Vitamin C+etoposide 복합투여에 의한 전립선 암세포 성장 억제의 상승 효과)

  • Lee, Myeong-Seon
    • Applied Microscopy
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    • v.38 no.3
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    • pp.245-250
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    • 2008
  • Etoposide (Eto) is chemotherapeutic compounds that is currently used in the treatment of metastatic prostate cancer but new therapeutic agents are needed for the treatment of androgen-independent prostate cancer. The objective of the present study was to determine whether vitamin C (VC), the antioxidant, plays a role in regulating the growth of prostate cancer cell lines and whether VC has synergistic effect to tumor cell killing by chemotherapeutic drugs. Androgen-dependent LNCaP and androgen-independent DU-145 prostate cancer cell lines were used in this study. Both cells presented increase of dose- and time-dependent cytotoxicity in Eto-treated cultures. The combined treatment with Eto and VC significantly increased the percentage of apoptotic cells compared to Eto-treated cells(p<0.05). The present findings demonstrated that VC inhibited the growth of prostate cancer cell lines by Eto-mediated cytotoxicity and induced apoptosis. These results suggest that the chemotherapeutic effect of Eto on prostate cancer can be enhanced by VC.

Growth and Chlorophyiil Biosynthesis of Vigna angularis under Lead Stress

  • Koo Suh-Young;Jin Sun-Young;Hong Jung-Hee
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.1 no.2
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    • pp.145-155
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    • 1997
  • The effect of various supplies of lead singly and in combination with aluminium on growth and chlorophyll biosynthesis was investigated in 7-day-old Vigna angularis seedlings. Expose to 50 uM Pb or more drastically reduced root elongation rate. Significant depressions in root growth was observed within 1 day and no recovery of growth was seen over the duration of treatment period. Root elongation decreased depending on the Pb concentrations. Root growth inhibition was stronger than shoot growth inhibition. The initiation of lateral roots appeared to be more sensitive to Pb than the growth of main roots. Inhibition of root and shoot elongation by Pb was lessened by combined exposure of Pb and Al, suggesting that the presence of Al reverse the inhibitory effect of Pb alone. With the histochemical sodium rhodizonate method the rate of Pb uptake was dependent on the Pb concentration and exposure time of the roots to Pb salts. Pb was first deposited on the root surface and then translocated radially in the root cap cells. During a longer Pb administration (up to 72 h) Pb penetration was nonuniform, with accumulation within the cortex or endodermis. There was drastic reduction in chlorophyll content by Pb. The Pb inhibition of chlorophyll synthesis was concentration dependent. $\delta-Aminolevulinic$ acid dehydratase (ALAD) activity exhibited distinct inhibition from control. Reduction in chlorophyll content was accompanied by proportional changes in ALAD activity. Chlorophyll content and ALAD activity were less affected by combined exposure of Pb and Al, suggesting that Al has a protective effect against the inhibiting action of Pb on photosynthetic activity.

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INITIATION OF LIPID PEROXIDATION AS A RESULT OF THE COMBINED ACTION OF FERRIC IRON AND LIGHT ON MEMBRANES

  • Park, Zee-Yong;Kim, Chang-Sook;Jung, Jin
    • Journal of Photoscience
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    • v.1 no.2
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    • pp.83-88
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    • 1994
  • The synergic effect of iron plus blue light on the peroxidation of membrane lipid was investigated, using liposomes made of phospholipid. While strong irradiation did not affect Fe$^{+2}$-promoted lipid peroxidation that turned out to be O$_2$-dependent, ferric iron in bright light exerted a pronounced effect on the initiation of lipid peroxidation: this combined action of light and Fe$^{+3}$ on liposomal membranes was apparently independent of O$_2$. When liposomal samples containing Fe$^{+3}$ were subjected to irradiation, some portions of Fe$^{+3}$ were converted into Fe$^{+2}$. The extent of the Fe$^{+3}$-Fe$^{+2}$ conversion increased with increasing time of irradiation, which resembled the dependence of Fe$^{+3}$-promoted lipid peroxidation on irradiation. Further, it was observed that the effect of irradiation in liposomal samples containing Fe$^{+2}$ was strikingly mimicked by that of Fe$^{+2}$ addition to the same samples. The obligatory requirement of a suitable Fe$^{+3}$/Fe$^{+2}$ ratio for the genesis of iron-dependent lipid peroxidation, a controversial proposition, was also confirmed by the observation that lipid peroxidation was substantially enhanced by the addition of a mixture of Fe$^{+3}$ and Fe$^{+2}$, as compared to the addition of Fe$^{+3}$ or Fe$^{+2}$ alone. The results obtained in this study not only suggest that light acts as an effector for initiating lipid peroxidation, when Fe$^{+3}$ is present in membrane systems, but also imply that any chemical or physical factor that influences the redox states of iron in membranes can play a role in lipid peroxidation reactions.

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The Effect of Reform of New Diagnosis-Related Groups on Coverage of National Health Insurance (신포괄수가 시범사업 모형개선이 건강보험 보장률에 미친 영향)

  • Choi, Jung-Kyu;Kim, Seon-Hee;Chang, Cheong-Ha;Yoon, Jong-Min;Kang, Jung-Gu
    • Health Policy and Management
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    • v.30 no.2
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    • pp.178-184
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    • 2020
  • Background: Korea set up a new diagnosis-related group as a demonstration project in 2009. The new diagnosis-related group was reformed in 2016. The main purpose of the study is to identify the effect of reform on coverage of national health insurance. Methods: This study collected inpatient data from a hospital that contains medical information and cost from 2015 July to 2016 June. The dependent variable was the coverage of national health insurance. The dependent variable was divided by total, internal medicine partition, surgical partition, and psychiatric partition. To analyze the effect of the reform, this study conducted an interrupted time series analysis. The final sample included 23,695. Results: The health insurance coverage of internal medicine has the highest, followed by surgery and psychiatry. The health insurance coverage of bundle payment is higher than that of unbundled payment. The proportion of bundled payment and non-benefit decreased and the proportion of unbundled payment increased. The coverage of national health insurance significantly increased after policy reform in internal medicine partition (p-value=0.0356). Conclusion: The results of the study imply that policy reform enhanced the coverage of national health insurance in internal medicine. The government needs to monitor side effects such as an increase of unbundled payment.

Effect of Doxorubicin on Catecholamine Release in the Isolated Perfused Rat Adrenal Gland

  • Lim, Dong-Yoon;Oh, Song-Hoon;Seoh, Yoo-Seung;Lee, Eun-Sook;Kim, Il-Hwan;Jo, Seong-Ho;Hong, Soon-Pyo
    • The Korean Journal of Physiology and Pharmacology
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    • v.6 no.4
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    • pp.215-223
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    • 2002
  • The present study was undertaken to investigate the effect of doxorubicin (DX) on secretion of catecholamines (CA) evoked by ACh, high $K^+,$ DMPP and McN-A-343 from the isolated perfused rat adrenal gland and to establish the mechanism of its action. DX $(10^{-7}{\sim}10^{-6}\;M)$ perfused into an adrenal vein for 60 min produced relatively dose- and time-dependent inhibition of CA secretory responses evoked by ACh $(5.32{\times}10^{-3}\;M),$ DMPP $(10^{-4}\;M)$ and McN-A-343 $(10^{-4}\;M).$ However, lower dose of DX did not affect CA secretion by high $K^+\;(5.6{\times}10^{-2}\;M),$ but its higher doses depressed time-dependently CA secretion evoked by high $K^+.$ DX itself did also fail to affect basal CA output. In adrenal glands loaded with DX $(3{\times}10^{-7}\;M),$ CA secretory responses evoked by Bay-K-8644, an activator of L-type $Ca^{2+}$ channels and cyclopiazonic acid, an inhibitor of cytoplasmic $Ca^{2+}-ATPase$ were time-dependently inhibited. Furthermore, daunorubicin $(3{\times}10^{-7}\;M),$ given into the adrenal gland for 60 min, attenuated CA secretory responses evoked by ACh, high $K^+,$ DMPP and McN-A-343. Taken together, these results suggest that DX causes relatively dose- and time-dependent inhibition of CA secretory responses evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors from the isolated perfused rat adrenal gland. However, lower dose of DX did not affect CA secretion by high $K^+,$ and higher doses of DX reduced time-dependently CA secretion of high $K^+.$ It is thought that these effects of DX may be mediated by inhibiting both influx of extracellular calcium into the rat adrenomedullary chromaffin cells and intracelluar calcium release from the cytoplasmic store. Also, there was no difference in the mode of action between DX and daunorubicin in rat adrenomedullary CA secretion.