• Title/Summary/Keyword: Well-regulated

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Renal Expression of TonEBP and Urea Transporter in the Water-deprived Mongolian Gerbil(Meriones unguiculatus) (절수시 Mongolian Gerbil 콩팥에서 TonEBP와 Urea transporter의 발현 변화)

  • Park, Yong-Deok;Kim, Sung-Joong;Jung, Ju-Young
    • Applied Microscopy
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    • v.37 no.4
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    • pp.271-280
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    • 2007
  • Tonicity-responsive enhancer binding protein(TonEBP) is a transcriptional factor essential in the function and development of the renal medulla. TonEBP plays a critical role in protecting renal medullary cells from the deleterious effect of hypertonicity. TonEBP is a key regulator of urinary concentration via stimulation of transcription of urea transporter(UT) in a manner independent of vasopressin. UT in the renal inner medulla is important for the conservation of body water due to its role in the urine concentrating mechanism. Mongolian gerbil(Meriones unguiculatus) has been as an model animal for studying the neurological disease such as stroke and epilepsy because of the congenital incomplete in Willis circle, as well as the investigation of water metabolism because of the long time-survival in the condition of water-deprived desert condition, compared with other species animal. In this study, we divide 3 groups of which each group include the 5 animals. In the study of 7 or 14 days water restricted condition, we investigated the TonEBP and UT-A by using a immunohistochemistry in the kidney. In the normal kidney, the distribution of TonEBP is generally localized on nuclei of inner medullary cells. Nuclear distribution of TonEBP is generally increased throughout the medulla in 7 and 14 days dehydrated group compared with control group. Increased nuclear localization was particularly dramatic in thin limbs. In control groups, UT-A was expressed in inner stripe of outer medulla(ISOM) and inner medulla(IM). UT-A was present in the terminal part of the short-loop of descending thin limbs (DTL) in ISOM and also present in the inner medullary collecting duct(IMCD), where the intensity of it gradually increased toward the papillary tip. In the dehydrated kidney, UT-A immunoreactivity was increased in the short-loop of DTL in ISOM and in the long-loop of DTL in the initial part of IM, where was expressed moderate positive reaction in the normal kidney. Also it was up regulated in the IMCD in initial & middle part of IM. However UT-A down regulated in the IMCD, where the intensity of it gradually decreased toward the papillary tip. These findings suggest that increased levels of TonEBP in medulla and UT-A in shot-loop of DTL and IMCD play a important role for maintain fluid balance in the water-deprived mongolian gerbil kidney.

Biological Functions of N- and O-linked Oligosaccharides of Equine Chorionic Gonadotropin and Lutropin/Chorionic Gonadotropin Receptor

  • Min, K.S.
    • Korean Journal of Animal Reproduction
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    • v.24 no.4
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    • pp.357-364
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    • 2000
  • Members of the glycoprotein family, which includes CG, LH, FSH and TSH, comprise two noncovalently linked $\alpha$- and $\beta$-subunits. Equine chorionic gonadotropin (eCG), known as PMSG, has a number of interesting and unique characteristics since it appears to be a single molecule that possesses both LH- and FSH-like activities in other species than the horse. This dual activity of eCG in heterologous species is of fundamental interest to the study of the structure-function relationships of gonadotropins and their receptors. CG and LH $\beta$ genes are different in primates. In horse, however, a single gene encodes both eCG and eLH $\beta$ -subunits. The subunit mRNA levels seem to be independently regulated and their imbalance may account for differences in the quantities of $\alpha$ - and $\beta$-subunits in the placenta and pituitary. The dual activities of eCG could be separated by removal of the N-linked oligosaccharide on the $\alpha$-subunit Asn 56 or CTP-associated O-linked oligosaccharides. The tethered-eCG was efficiently secreted and showed similar LH-like activity to the dimeric eCG. Interestingly, the FSH-like activity of the tethered-eCG was increased markedly in comparison with the native and wild type eCG. These results also suggest that this molecular can implay particular models of FSH-like activity not LH-like activity in the eCG/indicate that the constructs of tethered molecule will be useful in the study of mutants that affect subunit association and/or secretion. A single-chain analog can also be constructed to include additional hormone-specific bioactive generating potentially efficacious compounds that have only FSH-like activity. The LH/CG receptor (LH/CGR), a membrane glycoprotein that is present on testicular Leydig cells and ovarian theca, granulosa, luteal, and interstitial cells, plays a pivotal role in the regulation of gonadal development and function in males as well as in nonpregnant and pregnant females. The LH/CGR is a member of the family of G protein-coupled receptors and its structure is predicted to of a large extracellular domain connected to a bundle of seven membrane-spanning a-helices. The LH/CGR phosphorylation can be induced with a phorbol ester, but not with a calcium ionophore. The truncated form of LHR also was down-regulated normally in response to hCG stimulation. In contrast, the cell lines expressing LHR-t631 or LHR-628, the two phosphorylation-negative receptor mutant, showed a delay in the early phase of hCG-induced desensitization, a complete loss of PMA-induced desensitization, and an increase in the rate of hCG-induced receptor down-regulation. These results clearly show that residues 632~653 in the C-terminal tail of the LHR are involved in PMA-induced desensitization, hCG-induced desensitization, and hCG-induced down-regulation. Recently, constitutively activating mutations of the receptor have been identified that are associated with familial male-precocious puberty. Cells expressing LHR-D556Y bind hCG with normal affinity, exhibit a 25-fold increase in basal cAMP and respond to hCG with a normal increase in cAMP accumulation. This mutation enhances the internalization of the free and agoinst-occupied receptors ~2- and ~17- fold, respectively. We conclude that the state of activation of the LHR can modulate its basal and/or agonist-stimulated internalization. Since the internalization of hCG is involved in the termination of hCG actions, we suggest that the lack of responsiveness detected in cells expressing LHR-L435R is due to the fast rate of internalization of the bound hCG. This statement is supported by the finding that hCG responsiveness is restored when the cells are lysed and signal transduction is measured in a subcellular fraction (membranes) that cannot internalize the bound hormone.

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Regulation of Tumor Neceosis Factor-${\alpha}$ Receptors and Signal Transduction Pathways

  • Han, Hyung-Mee
    • Toxicological Research
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    • v.8 no.2
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    • pp.343-357
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    • 1992
  • Tumor necrosis factor-${\alpha}$(TNF), a polypeptide hormone secreted primarily by activated macrophages, was originally identified on the basis of its ability to cause hemorrhagic necrosis and tumor regression in vivo. Subsequently, TNF has been shown to be an important component of the host responses to infection and cancer and may mediate the wasting syndrome known as cachexia. These systemic actions of TNF are reflected in its diverse effects on target cells in vitro. TNF initiates its diverse cellular actions by binding to specific cell surface receptors. Although TNF receptors have been identified on most of animal cells, regulation of these receptors and the mechanisms which transduce TNF receptor binding into cellular responses are not well understood. Therefore, in the present study, the mechanisms how TNF receptors are being regulated and how TNF receptor binding is being transduced into cellular responses were investigated in rat liver plasma membranes (PM) and ME-180 human cervical carcinoma cell lines. $^{125}I$-TNF bound to high ($K_d=1.51{\pm}0.35nM$)affinity receptors in rat liver PM. Solubilization of PM with 1% Triton X-100 increased both high affinity (from $0.33{\pm}0.04\;to\;1.67{\pm}0.05$ pmoles/mg protein) and low affinity (from $1.92{\pm}0.16\;to\;7.57{\pm}0.50$ pmoles/mg protein) TNF binding without affecting the affinities for TNF, suggesting the presence of a large latent pool of TNF receptors. Affinity labeling of receptors whether from PM or solubilized PM resulted in cross-linking of $^{125}I$-TNF into $M_r$ 130 kDa, 90 kDa and 66kDa complexes. Thus, the properties of the latent TNF receptors were similar to those initially accessible to TNF. To determine if exposure of latent receptors is regulated by TNF, $^{125}I$-TNF binding to control and TNF-pretreated membranes were assayed. Specific binding was increased by pretreatment with TNF (P<0.05), demonstrating that hepatic PM contains latent TNF receptors whose exposure is promoted by TNF. Homologous up-regulation of TNF receptors may, in part, be responsible for sustained hepatic responsiveness during chronic exposure to TNF. As a next step, the post-receptor events induced by TNF were examined. Although the signal transduction pathways for TNF have not been delineated clearly, the actions of many other hormones are mediated by the reversible phosphorylation of specific enzymes or target proteins. The present study demonstrated that TNF induces phosphorylation of 28 kDa protein (p28). Two dimensional soidum dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) resolved the 28kDa phosphoprotein into two isoforms having pIs of 6.2 and 6.1. The pIs and relative molecular weight of p28 were consistent with those of a previously characterized mRNA cap binding protein. mRNA cap binding proteins are a class of translation initiation factors that recognize the 7-methylguanosine cap structure found on the 5' end of eukaryotic mRNAs. In vitro, these proteins are defined by their specific elution from affinity columns composed of 7-methylguanosine 5'-triphosphate($m^7$GTP)-Sepharose. Affinity purification of mRNA cap binding proteins from control and TNF treated ME-180 cells proved that TNF rapidly stimulates phosphorylation of an mRNA cap binding protein. Phosphorylation occurred in several cell types that are important in vitro models of TNF action. The mRNA cap binding protein phosphorylated in response to TNF treatment was purifice, sequenced, and identified as the proto-oncogene product eukaryotic initiation factor-4E(eIF-4E). These data show that phosphorylation of a key component of the cellular translational machinery is a common early event in the diverse cellular actions of TNF.

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A Study of Health Consciousness and Physical Therapy Cognition of Old Ages (고령자의 건강의식과 물리치료 인식에 관한 연구)

  • Park Hwan-Jin;Park Rae-Joon;Kim Han-Soo
    • The Journal of Korean Physical Therapy
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    • v.12 no.2
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    • pp.175-184
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    • 2000
  • This study which applies to the 403 healthy people who don't have particular diseases recently(193 urban aged. 210 rural aged) among male and female aged over 60 years old living in Daegu(city) and Gyungbook(agricultural village) is fulfilled from November 1st to December 31st by interview using the questioned paper which researcher developed, and reached to these tallowing conclusions. 1. Every aged men independent of the place residence answered positively yes but aged women had weak assurance of their health. Especially $38.6\%$ of rural aged women said yes and $51.4\%$ of rural aged women said no. 2. In the sleep and well-regulated life, urban and rural aged generally marked on the sound sleep. Compared with male and female, men answered they had better sleep and regulated life than women. 3. The percentage of the urban and rural aged's judgement on their activity was high and the percentage of the rural aged was lower than the percentage of the urban aged. 4. While $62.6\%$ of urban aged answered they were active. $38.6\%$ of rural female aged answered yes, This shows that the rural female aged regard their health is not good. 5. Compared with same generation. urban aged ranked lower than urban aged in the confidence of physical strength. Especially rural need women answered $42.1\%$ of them were weaker than the same generation. This shows that rural aged women don't have confidence in general physical activities. 6. Taking exercises three times a week which can influence on health cue to sixties and seventies aged ranked $26.1\%$, rarely do is $18.8\%$ and never do is$28.8\%$. Urban and rural aged do not exercise on the purpose of health. 7. The reason of exercise was to advance the physical strength and quality of motion$(34.9\%)$ to get rid of stress$(13.4\%)$ and to prevention of adult illness$(27.8\%)$, prevention of fatness$(15.3\%)$. Aged have a correct understanding that exercise can promote health and protect from the diseases of adult people because the items about the diseases of adult people was marked high. 8. Among the subject of total investigation, 209 persons answered. It showed necessary to recognize that the exercise is still important essential part between adult illness and health care. 9. The $67.7\%$ of urban aged men answered yes in the question of undergoing a physical examination but the rate of not undergoing a physical examination was high in rural aged and urban aged women. According to this, there were the difference of consciousness about health between urban and rural aged. and men and women. 10. Among the people who haying undergone the physical examination, $80.3\%$ of the aged went back to the hospital again because of the result. 11. In the case of stroke, most aged answered the would be placed under medical care. but $53.9\%$ of rural aged women answered they would rely on Chinese medicine. According to this. aged preferred Chinese medicine in some particular diseases. 2. The $58.1\%$ of whole object of this study answered that stroke would be recovered.

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The Protective Role of Gleditsiae fructus against Streptococcus pneumoniae (폐렴 구균에 대한 조협의 보호 역할 연구)

  • Jun-ki Lee;Se-Hui Lee;Dong Ju Seo;Kang-Hee Lee;Sojung Park;Sun Park;Taekyung Kim;Jin-Young Yang
    • Journal of Life Science
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    • v.33 no.2
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    • pp.158-168
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    • 2023
  • Natural products have been used to mitigate the effects of cancer and infectious diseases, as they feature diverse bioactivities, such as antioxidant, antibacterial, anti-inflammatory, and immunomodulatory effects. Here, we chose 10 natural products that are well-known as pulmonary enhancers and investigated their bactericidal effects on Streptococcus pneumoniae. In the disk diffusion assay, the growth of S. pneumoniae was significantly regulated by G. fructus treatment regardless of extraction method used. We first adopted spraying as a novel delivery method for G. fructus. Interestingly, mice exposed to G. fructus three times a day for 2 weeks were resistant to S. pneumoniae intranasal infection (shown both through body weight loss and survival rates compared to the control group). Moreover, we confirmed that exposure to G. fructus regulated the colonization of the bacteria despite the sustained inflammation in the lung after exposure to S. pneumoniae, indicating that migrated inflammatory immune cells may involve a host defense mechanism against pulmonary infectious diseases. While a similar number of granulocytes (CD11b+Ly6C+Ly6G+), neutrophils (CD11b+Ly6CintLy6G+), and monocytes (CD11b+Ly6CintLy6G-) were found between groups, a significantly increased number of alveolar macrophages (CD11b+CD11chiF4/80+) was detected in BAL fluids of mice pre-exposed to G. fructus at 5 days after S. pneumonia infection. Taken together, our data suggest that this usage of G. fructus can induce protective immunity against bacterial infection, indicating that facial spray may be helpful in enhancing the defense mechanism against pulmonary inflammation and in evaluating the efficacy of natural products as immune enhancers against respiratory diseases.

A Study on The Enhancement of Aviation Safety in Airport Planning & Construction from a Legal Perspective (공항개발계획과 사업에서의 항공안전성 제고에 대한 법률적 소고)

  • Kim, Tae-Han
    • The Korean Journal of Air & Space Law and Policy
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    • v.27 no.2
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    • pp.67-106
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    • 2012
  • Today air traffic at the airport is complicated including a significant increase in the volume of air transport, so aviation accidents are constantly occurring. Therefore, we should newly recognize importance of the Air Traffic Safety, the core values of the Air Traffic. The location of airport that is the basic infrastructure of the air traffic and the security of safety for facilities and equipments are more important than what you can. From this dimension, I analyze the step-by-step safety factors that are taken into account in the airport development projects from the construction or improvement of the airport within the current laws and institutions and give my opinion on the enhancement of safety in the design and construction of airport. The safety of air traffic, as well as airport, depends on location, development, design, construction, inspection and management of the airport including airport facilities because we have to carry out the national responsibility that prevents the risk of large social overhead capital for many and unspecified persons in modern society through legislation regarding intervention of specialists and locational criteria for aviation safety from the planning stage of airport development. In addition, well-defined installation standards of airports and air navigation facilities, the key points of the airport development phase, can ensure the safety of the airport and airport facilities. Of course, the installation standards of airport and air navigation facilities are based on the global standard due to the nature of air traffic. However, to prevent the chaos for the safety standards in design, construction, inspection of them and to ensure the aviation safety, the safety standards must be further subdivided in the course of domestic legislation. The criteria for installation of the Air Navigation facilities is regulated most specifically. However, to ensure the safety of the operation for Air Navigation Facilities, performance system proved suitable for the Safety of Air Navigation Facilities must change over from arbitrary restrictions to mandatory restrictions and be applied for foreign producers as well as domestic producers. Of course, negligence of pilots and defective aircraft maintenance lead to a large portion of the aviation accidents. However, I think that air traffic accidents can be reduced if the airport or airport facility is perfect enough to ensure the safety. Therefore, legal and institutional supplement to prioritize the aviation safety from the stage of airport development may be necessary.

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The Study of Anti-inflammatory Effect of Suryeon-hwan Water Extract in RAW 264.7 Cells (대식세포에서 수련환(茱連丸) 물추출물의 항염증작용에 관한 연구)

  • Yoon, Yeo-Hwan;Kim, Sung-Bae;Kang, Ok-Hwa;Mun, Su-Hyun;Seo, Yun-Soo;Yang, Da-Wun;Kang, Da-Hye;Wi, Gyeong;Lim, Jae-Soo;Kim, Ma-Ryong;Kwak, Nam-Won;Kong, Ryong;Kwon, Dong-Yeul
    • The Korea Journal of Herbology
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    • v.29 no.6
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    • pp.125-132
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    • 2014
  • Objectives : Suryeon-hwan (SRH) exhibits potent anti-inflammatory activity with an unknown mechanism. However, there has been a lack of studies regarding the effects of SRH on the inflammatory activities and effector inflammatory disease mechanism about macrophage before is not known. So, the investigation focused on whether SRH inhibited nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) productions, as well as the expressions of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and mitogen-activated protein kinases (MAPKs) in LPS-stimulated RAW 264.7 cells. Methods : Cells were treated with 200 ng/mL of LPS 30 min prior to the addition of SRH. Cell viability was measured by MTS assay. The production of nitric oxide (NO) was determined by reacting cultured medium with Griess reagent. The content of level of cytokines (PGE, IL-6) in media from LPS-stimulated Raw 264.7 cells was analyed by ELISA kit. The expression of COX-2, iNOS and MAPKs was investigated by Western blot, RT-PCR. Results : We found that SRH inhibited LPS-induced NO, $PGE_2$ and IL-6 productions as well as the expressions of iNOS and COX-2. Furthermore, SRH suppressed the LPS-induced phosphorylation of MAPK and extracellular signal-regulated kinase 1/2 (ERK 1/2) activation. Conclusions : These results suggest that SRH has inhibitory effects on LPS-induced $PGE_2$, NO, and IL-6 production, as well as the expressions of iNOS and COX-2 in the murine macrophage. These inhibitory effects occur through blockades on the phosphorylation of MAPKs following activation.

A Study on the Power Supply and Demand Policy to Minimize Social Cost in Competitive Market (경쟁시장 하에서 사회적 비용을 고려한 전력수급정책 방향에 관한 연구)

  • Kwon, Byung-Hun;Song, Byung Gun;Kang, Seung-Jin
    • Environmental and Resource Economics Review
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    • v.14 no.4
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    • pp.817-838
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    • 2005
  • In this paper, the resource adequacy as well as the optimum fuel mix is obtained by the following procedures. First, the regulation body, the government agency, determine the reliability index as well as the optimum portfolio of the fuel mix during the planning horizon. Here, the resources with the characteristics of public goods such as demand-side management, renewable resources are assigned in advance. Also, the optimum portfolio is determined by reflecting the economics, environmental characteristics, public acceptance, regional supply and demand, etc. Second, the government announces the required amount of each fuel-type new resources during the planning horizon and the market participants bid to the government based on their own estimated fixed cost. Here, the government announces the winners of the each auction by plant type and the guaranteed fixed cost is determined by the marginal auction price by plant type. Third, the energy market is run and the surplus of each plant except their cost (guaranteed fixed cost and operating cost) is withdrew by the regulatory body. Here, to induce the generators to reduce their operating cost some incentives for each generator is given based on their performance. The performance is determined by the mechanism of the performance-based regulation (PBR). Here the free-riding performance should be subtracted to guarantee the transparent competition. Although the suggested mechanism looks like very regulated one, it provides two mechanism of the competition. That is, one is in the resource construction auction and the other is in the energy spot market. Also the advantages of the proposed method are it guarantee the proper resource adequacy as well as the desired fuel mix. However, this mechanism should be sustained during the transient period of the deregulation only. Therefore, generation resource planning procedure and market mechanisms are suggested to minimize possible stranded costs.

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A study on the Regulatory Environment of the French Distribution Industry and the Intermarche's Management strategies

  • Choi, In-Sik;Lee, Sang-Youn
    • The Journal of Industrial Distribution & Business
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    • v.3 no.1
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    • pp.7-16
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    • 2012
  • Despite the enforcement of SSM control laws such as 'the Law of Developing the Distribution Industry (LDDI)' and 'the Law of Promoting Mutual Cooperation between Large and Small/medium Enterprises (LPMC)' stipulating the business adjustment system, the number of super-supermarkets (SSMs) has ever been expanding in Korea. In France, however, Super Centers are being regulated most strongly and directly in the whole Europe viewing that there is not a single SSM in Paris, which is emphasized to be the outcome from French government's regulation exerted on the opening of large scale retail stores. In France, the authority to approve store opening is deeply centralized and the store opening regulation is a socio-economic regulation driven by economic laws whereas EU strongly regulates the distribution industry. To control the French distribution industry, such seven laws and regulations as Commission départementale d'urbanisme commercial guidelines (CDLIC) (1969), the Royer Law (1973), the Doubin Law (1990), the Sapin Law (1993), the Raffarin Law (1996), solidarite et renouvellement urbains (SRU) (2000), and Loi de modernisation de l'économie (LME) (2009) have been promulgated one by one since the amendment of the Fontanet guidelines, through which commercial adjustment laws and regulations have been complemented and reinforced while regulatory measures have been taken. Even in the course of forming such strong regulatory laws, InterMarche, the largest supermarket chain in France, has been in existence as a global enterprise specialized in retail distribution with over 4,000 stores in Europe. InterMarche's business can be divided largely into two segments of food and non-food. As a supermarket chain, InterMarche's food segment has 2,300 stores in Europe and as a hard-discounter store chain in France, Netto has 420 stores. Restaumarch is a chain of traditional family restaurants and the steak house restaurant chain of Poivre Rouge has 4 restaurants currently. In addition, there are others like Ecomarche which is a supermarket chain for small and medium cities. In the non-food segment, the DIY and gardening chain of Bricomarche has a total of 620 stores in Europe. And the car-related chain of Roady has a total of 158 stores in Europe. There is the clothing chain of Veti as well. In view of InterMarche's management strategies, since its distribution strategy is to sell goods at cheap prices, buying goods cheap only is not enough. In other words, in order to sell goods cheap, it is all important to buy goods cheap, manage them cheap, systemize them cheap, and transport them cheap. In quality assurance, InterMarche has guaranteed the purchase safety for consumers by providing its own private brand products. InterMarche has 90 private brands of its own, thus being the retailer with the largest number of distributor brands in France. In view of its IT service strategy, InterMarche is utilizing a high performance IT system so as to obtainas much of the market information as possible and also to find out the best locations for opening stores. In its global expansion strategy of international alliance, InterMarche has established the ALDIS group together with the distribution enterprises of both Spain and Germany in order to expand its food purchase, whereas in the non-food segment, it has established the ARENA group in alliance with 11 international distribution enterprises. Such strategies of InterMarche have been intended to find out the consumer needs for both price and quality of goods and to secure the purchase and supply networks which are closely localized. It is necessary to cope promptly with the constantly changing circumstances through being unified with relevant regions and by providing diversified customer services as well. In view of the InterMarche's positive policy for promoting local partnerships as well as the assistance for enhancing the local economic structure, implications are existing for those retail distributors of our country.

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Nutritional and Tissue Specificity of IGF-I and IGFBP-2 Gene Expression in Growing Chickens - A Review -

  • Kita, K.;Nagao, K.;Okumura, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.5
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    • pp.747-754
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    • 2005
  • Nutritional regulation of gene expression associated with growth and feeding behavior in avian species can become an important technique to improve poultry production according to the supply of nutrients in the diet. Insulin-like growth factor-I (IGF-I) found in chickens has been characterized to be a 70 amino acid polypeptide and plays an important role in growth and metabolism. Although it is been well known that IGF-I is highly associated with embryonic development and post-hatching growth, changes in the distribution of IGF-I gene expression throughout early- to late-embryogenesis have not been studied so far. We revealed that the developmental pattern of IGF-I gene expression during embryogenesis differed among various tissues. No bands of IGF-I mRNA were detected in embryonic liver at 7 days of incubation, and thereafter the amount of hepatic IGF-I mRNA was increased from 14 to 20 days of incubation. In eyes, a peak in IGF-I mRNA levels occurred at mid-embryogenesis, but by contrast, IGF-I mRNA was barely detectable in the heart throughout all incubation periods. In the muscle, no significant difference in IGF-I gene expression was observed during different stages of embryogenesis. After hatching, hepatic IGF-I gene expression as well as plasma IGF-I concentration increases rapidly with age, reaches a peak before sexual maturity, and then declines. The IGF-I gene expression is very sensitive to changes in nutritional conditions. Food-restriction and fasting decreased hepatic IGF-I gene expression and refeeding restored IGF-I gene expression to the level of fed chickens. Dietary protein is also a very strong factor in changing hepatic IGF-I gene expression. Refeeding with dietary protein alone successfully restored hepatic IGF-I gene expression of fasted chickens to the level of fed controls. In most circumstances, IGF-I makes a complex with specific high-affinity IGF-binding proteins (IGFBPs). So far, four different IGFBPs have been identified in avian species and the major IGFBP in chicken plasma has been reported to be IGFBP-2. We studied the relationship between nutritional status and IGFBP-2 gene expression in various tissues of young chickens. In the liver of fed chickens, almost no IGFBP-2 mRNA was detected. However, fasting markedly increased hepatic IGFBP-2 gene expression, and the level was reduced after refeeding. In the gizzard of well-fed young chickens, IGFBP-2 gene expression was detected and fasting significantly elevated gizzard IGFBP-2 mRNA levels to about double that of fed controls. After refeeding, gizzard IGFBP-2 gene expression decreased similar to hepatic IGFBP-2 gene expression. In the brain, IGFBP-2 mRNA was observed in fed chickens and had significantly decreased by fasting. In the kidney, IGFBP-2 gene expression was observed but not influenced by fasting and refeeding. Recently, we have demonstrated in vivo that gizzard and hepatic IGFBP-2 gene expression in fasted chickens was rapidly reduced by intravenous administration of insulin, as indicated that in young chickens the reduction in gizzard and hepatic IGFBP-2 gene expression in vivo stimulated by malnutrition may be, in part, regulated by means of the increase in plasma insulin concentration via an insulin-response element. The influence of dietary protein source (isolated soybean protein vs. casein) and the supplementation of essential amino acids on gizzard IGFBP-2 gene expression was examined. In both soybean protein and casein diet groups, the deficiency of essential amino acids stimulated chickens to increase gizzard IGFBP-2 gene expression. Although amino acid supplementation of a soybean protein diet significantly decreased gizzard IGFBP-2 mRNA levels, a similar reduction was not observed in chickens fed a casein diet supplemented with amino acids. This overview of nutritional regulation of IGF-I and IGFBP-2 gene expression in young chickens would serve for the establishment of the supply of nutrients to diets to improve poultry production.