• Title/Summary/Keyword: size dependent effect

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Effect of Dietary Fat Sources and L-arginine Supplementation on Endothelial function and Lipid Metabolism in Streptozotocin-Induced Diabetic Rats (식이지방의 종류와 L-arginine 보충이 당뇨쥐의 ENdothelium 기능 및 체내 지질대사에 미치는 영향)

  • 장문정;김연중;김명환
    • Journal of Nutrition and Health
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    • v.35 no.1
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    • pp.5-14
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    • 2002
  • Alteration in the syntesis or enhanced inactivation of nitric oxide(NO) can induce impairment of endothelial cell function. Insulin dependent diabetes mellitus(IDDM) is characterized by impaired endothelial function and vascular disease. NO is produced through L-arginine pathway To elucidate the hypothesis that the decreased production on NO in IDDM reflects vascular damage and the NO production can be manipulated by either dietary fat(7% of kg diet) or the oral supplementation with L-arginine(2g/kg bw), plasma markers for vascular endothelial damage and plasma lipid profiles were measured in streptozotocin(STZ)-induced diabetic rats. Diabetic or normal Sprague-Dawley rats were fed 6 different experimental diets for 4 weeks(SO : soybean oil, SOA: soybean oil + L-arginine supplementation, BT : beef tallow, BTA_ beef tallow + L-arginine supplementation, OV olive oil, OVA : olive oil + L-arginine supplementation). Plasma glucose, total cholesterel, HDL-cholesterol, LDL-cholesterol and triglyceride were measured. Endothelial markers, plasma von Willebrand factor(vWf), thromboxane B$_2$, and 6-keto PGF1$\alpha$ of aorta were measured by ELISA. Plasma NO production was evaluated through the measurement of nitrite by EIA. Feeding saturated fatty acid(SFA, BT) increased relative liver size(RLS) in diabetic rats compared to either polyunsatunted fatty acid(PUFA, SO) or monounsaturated fatty acid(MUFA, OV) The supplementation of L-arginine inhibited the liver and kidney enlargement in olive oil find diabetic rats. Plasma glucose was lower in diabetic animal find the olive oil compared to fed beef tallow and the supplementation L-arginine decreased it in diabetic rats find beef tallow significantly(p < 0.05). Plasma TXB$_2$ levels were increased due to diabetes and the value of beef tallow group showed highest value. Plasma vWf concentration of beef tallow group was higher value in normal rats and was elevated more in diabetes. In diabetic groups, the vWf concentration of olive oil group was lower than beef tallow or soybean oil group. The supplementation of L-arginine in diabetic rats decreased plasma TXB$_2$ and vWf levels significantly(p < 0.05). NO production was higher in normal olive oil fed rats and was tend to be decreased in diabetic rats and the supplementation of L-arginine recovered to normal value(p < 0.05), Olive oil supplemented with L-arginine tended to lower plasma total cholesterol and LDL-cholesterol after 4 week treatment. These results suggest that generalized vascular endothelial changes based on plasma TXB$_2$and vWf occurs in diabetic rats. and olive oil with L-arginine supplementation contributes to a better control of the hyperglycemia, endothelial changes and hypercholesterolemia accompanying diabetes as compared with beef tallow or soy bean oil in this rat model.

A Study on Retail Competition Structure in Traditional Market (전통시장 내 소매업 경쟁구조에 관한 연구)

  • Lee, Chul-Sung;Kim, Young-Ki;Kim, Seung-Hee
    • Journal of Distribution Science
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    • v.16 no.6
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    • pp.55-63
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    • 2018
  • Purpose - Our Research is a study on the competition structure between retailers in traditional markets. Specifically, this study examined the effects of SSM, commodity supply store, Hanaro mart, food mart and other mart in traditional markets on retail stores of small businesses. The purpose of this study is to provide a solution to the market encroachment of large retailers in traditional markets. Research design, data, and methodology - This study is based on the data of 'Market Survey of Traditional Market·Shopping Mall and Store Management in 2016' and 'Current status of SSM(Super SuperMarket), commodity supply store, Hanaro mart, food mart and other mart in the traditional market in 2017' conducted by Small Enterprise and Market Service. In this study, a multiple regression equation was constructed using the number of SSM, commodity supply store, Hanaro mart, food mart and other mart as an independent variable and sales, number of customers as a dependent variable for analysis. Results - The increase of SSM and commodity supply stores in the traditional market affects the sales decrease of the surrounding small merchants in the traditional market. This means that the SSM and commodity supply stores can lead to the decline of the traditional market. However, it has been found that the penetration of these companies in traditional markets does not affect the number of visitors. Second, Hanaro mart's entry into the traditional market has a negative impact on the sales and visitor numbers of the surrounding small-scale merchants. The increase in the number of food mart has a significant effect on the sales and the number of visitors to the small stores. The results of this study indicate that the food mart can contribute to the revitalization of traditional markets. Lastly, other mart with more than medium size were found to affect the sales of small stores, the number of visitors. Conclusions - We examines the competitive structure among retailers in traditional markets. The penetration of large retailers in traditional markets has a negative impact on traditional markets, particularly Hanaro mart has a greater impact than SSM. We provide practical and theoretical implications for the retail competition structure in traditional markets.

Anti-Obese Activity of HPJ Extract on High Fat Diet-Induced Obese Mice (고지방 식이로 유도된 비만 쥐에서 HPJ 추출물의 항비만 효과)

  • Yuan, Hai-Dan;Quan, Hai-Yan;Zhang, Ya;Kim, Sung-Jib;Shin, Dae-Hee;Lim, Bang-Ho;Chung, Sung-Hyun
    • YAKHAK HOEJI
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    • v.53 no.5
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    • pp.286-292
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    • 2009
  • In this study, we investigated the anti-obese activity of HPJ extract in C57BL/6J mice. The C57BL/6J mice were randomly divided into five groups: normal control group (Con), high fat diet control group (HFD), treatment groups with HPJ at 125 mg/kg (HPJ125), 250 mg/kg (HPJ250), or 500 mg/kg (HPJ500). To induce an obesity, mice were fed by a high fat diet for 6 weeks, and mice were administered with HPJ extract once a day for 8 weeks. At the end of treatment, we examined the effect of HPJ extract on body weight, plasma lipid, and lipogenic enzymes. HPJ extract was found to lower whole body and epididymal adipose tissue weights and lowered plasma levels of glucose, insulin, triglyceride (TG), total cholesterol (TC), non-esterified fatty acid (NEFA) and leptin, compared to those in HFD group. Histological analyses of the liver and fat tissues of mice treated with HPJ extract revealed significantly decreased number of lipid droplets and decreased size of adipocytes compared to the HFD group. In addition, HPJ extract preserved the morphological integrity of pancreatic islets. To elucidate an action mechanism of HPJ extract, Western blot and RT-PCR were performed using epididymal adipose tissues. HPJ extract up-regulated the levels of phosphorylated adenosine monophosphate-activated protein kinase (AMPK) and its substrate, acetyl-CoA carboxylasse (ACC). HPJ extract also attenuated lipogenic gene expressions of sterol regulatory element-binding protein $1{\alpha}$ (SREBP$1{\alpha}$), fatty acid synthase (FAS), sterol-CoA desaturase 1 (SCD1) and glycerol-3-phosphate acyltransferase (GPAT) in dose-dependent manners. In contrast, expressions of lipolytic genes such as peroxisome proliferator-activated receptor-$\alpha$ (PPAR-${\alpha}$) and CD36, and fatty acid $\beta$-oxidation gene, carnitine palmitoyltransferase-1 (CPT-1) were increased. These results suggest that HPJ extract ameliorates obesity through inhibiting synthesis of lipogenic enzymes as well as stimulating fatty acid oxidation resulting from activation of AMPK, and HPJ extract could be developed as a potential therapeutic agent for obese patients.

Effect of Cosurfactant on Preparation of Silica Nanoparticles using Water in Oil Microemulsion of Nonionic Surfactant (보조계면활성제가 비이온 계면활성제의 Water in Oil 마이크로에멀젼을 이용한 실리카 나노입자 제조에 미치는 영향)

  • Kim, TaeHoon;Lim, JongChoo
    • Korean Chemical Engineering Research
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    • v.46 no.2
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    • pp.356-368
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    • 2008
  • The effects of cosurfactant on silica nanoparticles were investigated in systems containing surfactant, oil and aqueous ammonia solution where nanoparticles were prepared using a single phase water-in-oil (W/O) microemulsion. For the same oil phase, a single phase region was dependent on the interaction between surfactant and oil. For the cyclohexane system, NP-5 surfactant showed a wider single phase region than NP-4. The addition of n-propanol as a cosurfactant resulted in an increase or a decrease of a single phase W/O microemulsion region depending on the continuous oil phase. For both cyclohexane and isooctane systems, the addition of n-propanol resulted in a decrease in the single phase region. On the other hand, for n-heptane system, the addition of n-propanol expanded a single phase W/O microemulsion region. Silica nanoparticles prepared within a single phase region showed that relatively large number of particles of irregular shape were obtained with the addition of n-propanol to NP surfactant system. The addition of n-propanol to LA-5 surfactant and n-heptane system produced a decrease in average particle size and an increase in the number of particles formed due to a decrease in the intermicellar exchange rate among microemulsion droplets.

Effects of Aluminium on Growth, Chlorophyll Content, ALAD Activity and Anatomy of Root rind Shoot in Azuki Bean (Vigna angularis) Seedlings (Aluminium이 팥(Vigna angularis) 유식물의 생장, 엽록소함량, ALAD활성 및 뿌리와 경엽부의 형태에 미치는 영향)

  • 구서영;홍정희
    • Journal of Environmental Science International
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    • v.5 no.6
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    • pp.813-826
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    • 1996
  • The toxic effects of aluminium (Al) on growth, chlorophyll content, $\delta-aminolevulinic$ acid dehydratase (ALAD) activity and anatomy of root and shoot were investigated in 7-day-old azuki bean (Vigna angularis) seedlings. Significant depressions in root elongation was observed in the low concentrations of Al (50, 100 $\muM)$ and increasing Al concentrations caused a sharp decline of root and shoot growth. The degree of inhibition was dependent upon Al supply. Exposure to 50 $\muM$ Al or more inhibited root elongation within 1 day. In the 50 $\muM$ Al treatments, a recovery of root growth was seen after 7 days exposure. In contrast, lateral root initials was little affected by Al exposure. Al toxicity symptoms and growth responses were more well developed in the roots than in the shoots. Analysis of Al localization in root cells by hematoxylin stAlning showed that Al entered root apices and accumulated in the epidermal and cortical cells immeadiately below the epidermis. There was a good positive correlation between the level of chlorophyll and ALAD activity. Increasing Al concentrations caused a decrease in total chlorophyll contents, accompanied by proportional changes in ALAD activity, suggesting a cootr-dinated reduction of a photosynthetic machinery. Al exerted specific influence on the morphology of root ann shoot. At higher concentrations of Al the roots induced drastic anatomical changes. The epidermal cells were disorganized or destructed while the cortical cells exhibited distortion of cell shape and/or disintegration. The diameter of root and transectional area of cortical cells decreased considerably with Al treatment. In the shoot Al also enhanced reduction of diameter of shoot and cell size. Gross anatomy of leaves treated with Al did not differ significantly from the controls, except for fewer and smaller chloroplast. Our results indicate that toxic effect of Al appear to be manifested primarily in roots and secondarily on shoots, and changes in root morphology are related to changes in the root growth patterns. Results are further discussed in re181ion to the findings in other plant species, and it is concluded that Al causes morphological, structural and, presumably, functional damage to the roots of the species investigated.

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PROTECTIVE ACTION OF N-ACETYLCYSTEINE AGAINST HEPATOTOXIC AGENTS IN ISOLATED RAT LIVER CELLS

  • Park, Soo-Hee;Dong, Mi-Sook;Kang, Dong-Chul;Lee, Ki-Wan;Cha, Young-Nam
    • Toxicological Research
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    • v.3 no.2
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    • pp.129-141
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    • 1987
  • Hepatocytes isolated from rats which have been pretreated with phenobarbital (80 mg/kg for 3 days), were able to take up N-acetylcysteine from surrounding medium and were able to synthesize the reduced glutathione ($GSH^{\ast}-3$) intracellularly. The N-acetylcysteine is quickly deacetylated after the uptake and increases the pool size of cysteine, which was very low initially (5 nmol/$10^6$ cells). From this increased intracellular cysteine pool, GSH was synthesized. Freshly isolated rat hepatocytes contained a high level of GSH (30 nmol/$10^6$ cells), but upon incubation with the diethylmaleate, it was markedly decreased (10 nmol/$10^6$ cells). The hepatocytes with depleted GSH have lost viability upon incubations with acetaminophen (5mM) and paraquat (2 mM). However, when the N-acetylcysteine (1 mM) was added to this incubation condition, these chemical induced hepatocellular necrosis were prevented for longer durations. This N-acetylcysteine dependent protective effect against the hepatotoxic chemicals was lost by adding methionine sulfoximine (10 mM), an inhibitor of GSH biosynthesis. Both the carbontetrachloride (5 mM) and chioroform (5 mM) added to the incubation medium caused rapid losses of GSH and cell viability, even without the prior depletion of cellular GSH. However, again, if the 1mM N-acetylcysteine was supplemented, the rates of losses of GSH and cell viability were retarded in both cases. Even though large amounts of the added N-acetylcysteine was present in the cell, N-acetylcysteine conjugate of acetaminophen was not formed. Instead, only large amounts of GSH conjugate of the drug was produced. Thus, it is concluded that the added N-acetylcysteine is taken up and utilized for resynthesis of GSH. In turn, this resynthesized GSH contributes to the protection against cytotoxicity inducible with hepatotoxic drugs.

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Is there an Association between Variants in Candidate Insulin Pathway Genes IGF-I, IGFBP-3, INSR, and IRS2 and Risk of Colorectal Cancer in the Iranian Population?

  • Karimi, Khatoon;Mahmoudi, Touraj;Karimi, Negar;Dolatmoradi, Hesamodin;Arkani, Maral;Farahani, Hamid;Vahedi, Mohsen;Parsimehr, Elham;Dabiri, Reza;Nobakht, Hossein;Asadi, Asadollah;Zali, Mohammad Reza
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.9
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    • pp.5011-5016
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    • 2013
  • Background: Several epidemiological studies have shown associations between colorectal cancer (CRC) risk and type 2 diabetes and obesity. Any effects would be expected to be mediated through the insulin pathway. Therefore it is possible that variants of genes encoding components of the insulin pathway play roles in CRC susceptibility. In this study, we hypothesized that polymorphisms in the genes involving the insulin pathway are associated with risk of CRC. Materials and Methods: The associations of four single nucleotide polymorphisms (SNPs) in IGF-I (rs6214), IGFBP-3 (rs3110697), INSR (rs1052371), and IRS2 (rs2289046) genes with the risk of CRC were evaluated using a case-control design with 167 CRC cases and 277 controls by the PCR-RFLP method. Results: Overall, we observed no significant difference in genotype and allele frequencies between the cases and controls for the IGF-I, IGFBP-3, INSR, IRS2 gene variants and CRC before or after adjusting for confounders (age, BMI, sex, and smoking status). However, we observed that the IRS2 (rs2289046) GG genotype compared with AA+AG genotypes has a protective effect for CRC in normal weight subjects (p=0.035, OR=0.259, 95%CI= 0.074-0.907). Conclusions: These findings do not support plausible associations between polymorphic variations in IGF-I, IGFBP-3, INSR, IRS2 genes and risk of CRC. However, the evidence for a link between the IRS2 (rs2289046) variant and risk of CRC dependent on the BMI of the subjects, requires confirmation in subsequent studies with greater sample size.

The Study of the Sham Acupuncture for Acupuncture Clinical Trials (침 임상시험 논문에 적용한 Sham Acupuncture에 대한 고찰)

  • Jung, Chan-Yung;Jang, Min-Gee;Cho, Jae-Yong;Kim, Eun-Jung;Park, In-Shik;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.25 no.6
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    • pp.77-93
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    • 2008
  • Objectives : Though there were many clinical studies of acupuncture effects they didn't have appropriate control group or use another therapy for control group. So, we didn't say it was true acupuncture effect, though subjects in clinical study improved. Recently several sham needles for control group were developed and validated. This study aimed at summarizing the validation studies of these needles and evaluating the control group of the acupuncture clinical study. Methods : Computerized literature searches were performed using 'acupuncture' and 'placebo or sham' with a limitation of the results to RCTs in Pubmed, Sciencedirect, NDSL, KISS, RISS. Data were extracted regarding study design, sample size, acupuncture point, stimulation form, credibility testing. And We have examined 106 acupuncture clinical studies published by Pubmed from January 1, 2005 to April 30, 2008. Data were extracted author's country, subject of study, type of study groups, type of control groups, type of blinding, difference between the results in the control groups. Results : Streitberger's placebo needle, Fink's sham needle, Park sham needle, Kim sham needle were developed. They were validated at domestic and abroad. But the results were deviation depending on the each of the researcher. They has shown that sample, acupuncture points, experiences or knowledge of acupuncture dependent on the results. Recent three years, acupuncture clinical trial had different results. Significant differences between Study group and control group emerged from using other therapy or non-treatment for control group. Many study has no significant differences using sham acupuncture for control groups. Conclusions : Acupuncture clinical studies need to meet several requirements. First of all, they require the basics of randomized controlled clinical studies such as blinding and the accurate implementation and description of randomization. And also need to research the unique circumstances of these studies such as the development of sham acupuncture and blinding method which differs from other clinical trials.

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The empirical study on relationship between agency problem and beneficiary's performance (대리인문제가 R&D지원사업 수혜기업성과에 미치는 영향에 관한 실증연구)

  • Yang, Dong-Woo;Choi, Woo-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.4
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    • pp.615-621
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    • 2016
  • This study examines whether there is agency cost in a public R&D subsidy program by applying agency theory. If there is agency cost, the composition ratio of the government subsidy and the firm's own R&D fund would have a significant (-) effect on technological performance. Companies that received a public R&D subsidy in Korea from 2000 to 2009 were selected as a sample. Frequency analysis and multiple regression analysis were used. The independent variables was the ratio of public R&D subsidy cost to the Firm's own R&D cost, and the dependent variables were the number of patent applications and the number of patents registered. The control variables were firm size and R&D cost. The results show that there are agency problems in the government-sponsored R&D system. A future study is needed to examine how much agency problems deteriorate the efficiency of the system.

Effects of Di-(2-ethylhexyl) phthalate (DEHP) on Ultrastructure of Rat Testis (흰쥐 정소의 미세구조에 미치는 Di-(2-ethylhexyl) phthalate (DEHP)의 영향)

  • Kim, Wan-Jong;Kil, Young-Chun;Shin, Kil-Sang
    • Applied Microscopy
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    • v.29 no.3
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    • pp.353-362
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    • 1999
  • Di-(2-ethylhexyl) phthalate (DEHP) is a plasticize. known as one of endocrine disruptors. The present study was carried out to investigate the ultrastructural changes of prepubertal rat testis after oral administration of DEHP in dosages of 1 g/kg, 3 g/kg or 5g/kg in 0.5 ml of corn oil daily for a week. This study revealed the DEHP inhibited the development of seminiferous tubules and induced structural changes on various cell types of the rat testis. Leydig cells, Sertoli cells and the developing germ cells seemed to be impaired their differentiations in terms of the structural changes of cell organelles. The increase of heterochromatin in amount were common features in all 3 cell types. In addition, the Leydig cells were characterized by the increases in number and size of lysosomes and the scantiness of smooth endoplasmic reticulum. The Sertoli cells became irregular in nuclear envelope and the cytoplasm decreased, but the number of lysosomes and vacuoles seemed to be increased. There were some indications of necrosis of the germ cells, such as vacuolized nucleus and segregated nucleolus. These detrimental effects of DEHP on the rat testis were dose dependent and suppressed spermatogenesis decreasing developing germ cells in number and appearances. The effect of DEHP on ultrastructure of rat testis, as its known physiological functions, seems come from the decreased level of testosterone by Leydig cells, followed by the abnomalities of Sertoli cells and the germ cells.

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