• Molecular & Cellular Toxicology
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• v.4 no.4
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• pp.348-354
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• 2008

Bisphenol A (BPA), an environmental endocrine disrupter, enters the human body continuously in food and drink. Young children are likely to be more vulnerable than adults to chemical exposure due to the immaturities of their organ systems, rapid physical development, and higher ventilation, metabolic rates, and activity levels. The direct effect of BPA on peripheral tissue might also be of importance to the development of insulin resistance. However, the influence that BPA has on insulin signaling molecules in skeletal muscle has not been previously investigated. In this study, we examined the effect of BPA on fasting blood glucose (FBG) in post-weaned Wistar rats and on insulin signaling proteins in C2C12 skeletal muscle cells. Subsequently, we investigated the effects of BPA on insulin-mediated Akt phosphorylation in C2C12 myotubes. In rats, BPA treatment (0.1-1,000 ng/mL for 24 hours) resulted in the increase of FBG and plasma insulin levels, and reduced insulin-mediated Akt phosphorylation. Furthermore, the mRNA expression of insulin receptor (IR) was decreased after 24 hours of BPA treatment in C2C12 cells in a dose-dependent manner, whereas the mRNA levels of other insulin signaling proteins, including insulin receptor substrate-1 (IRS-1) and 5'-AMP-dependent protein kinase (AMPK), were unaffected. Treatment with BPA increased GLUT4 expression and protein tyrosine phosphatase 1B (PTP1B) activity in C2C12 myotubes, but not in protein levels. We conclude that exposure to BPA can induce insulin resistance by decreasing IR gene expression, which is followed by a decrease in insulin- mediated Akt activation and increased PTP1B activity.

• Food Science and Preservation
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• v.24 no.7
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• pp.1007-1016
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• 2017

Melania snail (Semisulcospira libertina) was traditionally used as the healthy food in Korea. It was generally known to improve liver function and heal a diabetes. The aim of this study was to elucidate the anti-diabetic mechanism of melanian snail hydrolysates treated with protamex (MPH) by investigating the inhibitory action on protein tyrosine phosphatase 1B (PTP1B), the improving effect on the insulin resistance in C2C12 myoblast and the protective effect for pancreatic beta-cell (INS-1) under the glucose toxicity. The melania snail hydrolysates treated with protamex (MPH), which showed the highest degree of hydrolysis (43%), and inhibited effectively PTP1B activity ($IC_{50}=15.42{\pm}1.1{\mu}g/mL$), of which inhibitory effect was higher than usolic acid, positive control ($IC_{50}=16.65{\mu}g/mL$). MPH increased the glucose uptake in C2C12 myoblast treated with palmitic acid. In addition, MPH increased insulin mRNA expression level by over 160% with enhanced cell viability in INS-1 cell under the high glucose concentration (30 mM). These results suggest that MHP may improve the diabetic symptom by the inhibiting the PTP1B activity, increasing the glucose uptake in muscle cell and protecting the pancreatic beta-cell from glucose toxicity.

• Journal of KIISE
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• v.41 no.11
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• pp.892-899
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• 2014

Dynamic binary instrumentation is a code insertion technique for debugging a program without scattering its execution flow, while the program is running. Most dynamic instrumentations are implemented using dynamic binary translation techniques. Existing studies translated program codes dynamically by parsing the machine code stream to intermediate representation (IR) and then applying compilation techniques for IRs. However, they have high overhead during translation, which is a major cause of difficulty in applying the dynamic binary translation technique to the program which requires high responsiveness. In this paper, we introduce a light-weight dynamic binary instrumentation framework based on a novel dynamic binary translation technique which has low overhead while translating the program code. In order to reduce the translation overhead, our approach adopts a tabular-based address translation and exploits a translation bypassing scheme, which stores the translated address of a frequently called library function in advance. It then accesses the translated address and executes function codes without code translation when calling the function. Our experiment results demonstrated that the proposed approach outperforms the prior dynamic binary translation techniques from 2% up to 65%.

• Journal of Technology Innovation
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• v.24 no.4
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• pp.27-53
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• 2016

This case analyzed the efficiency of 79 R&D projects performed within one private research center in machine tools industry. DEA was used for efficiency analysis. Input variables were R&D investment expense and man-month. Output variables were achievement rate on target development period and expected net sales within 5-years. Samples are divided into product development, Prior technology development, and control technology development. The key result is that Prior technology showed the lowest efficiency because of high uncertainty. It was so difficult to determine its goals and to make its specific plans. With respect to scale, the proportions of CRS(constant returns to scale) were 34.6%, 14.3% and 38.9% for product development, prior technology, control technology respectively. As for IRS(increase returns to scale), they were 53.8%, 85.7% and 38.9% for product development, prior technology, control technology respectively. As for DRS(decrease returns to scale) they were 11.5%, 0% and 22.2% for product development, prior technology, control technology respectively. On the whole, in this case, insufficient input was more problematic than excessive input, which means the lack of investment in R&D. Prior technology can be the source of the future competitiveness of companies. To operate inefficient DMU efficiently, the optimal input should be managed and it is derived from comparison with the reference group.

• Journal of the Korean Society for information Management
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• v.21 no.3
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• pp.1-14
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• 2004

Visualization of documents will help users when they do search similar documents. and all research in information retrieval addresses itself to the problem of a user with an information need facing a data source containing an acceptable solution to that need. In various contexts. adequate solutions to this problem have included alphabetized cubbyholes housing papyrus rolls. microfilm registers. card catalogs and inverted files coded onto discs. Many information retrieval systems rely on the use of a document surrogate. Though they might be surprise to discover it. nearly every information seeker uses an array of document surrogates. Summaries. tables of contents. abstracts. reviews, and MARC recordsthese are all document surrogates. That is, they stand infor a document allowing a user to make some decision regarding it. whether to retrieve a book from the stacks, whether to read an entire article, etc. In this paper another type of document surrogate is investigated using a grouping method of term list. lising Multidimensional Scaling Method (MDS) those surrogates are visualized on two-dimensional graph. The distances between dots on the two-dimensional graph can be represented as the similarity of the documents. More close the distance. more similar the documents.

• BMB Reports
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• v.33 no.6
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• pp.454-462
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• 2000

Interleukin-4(IL-4) is known to be a major cytokine regulating immunoglobulin E(IgE) response by the induction of IgE production and type II IgE receptor(IgER II: CD23) expression. Recently, however, the role of neuroendocrine factors has been implicated in modulating the IgE response. Among various neuroendocrine growth factors, we investigated the effects of the insulin-like growth factor-1(IGF-1) since IL-4 and IGF-1 share common intracellular signaling molecules, such as the insulin receptor substrate-1/2(IRS-1/2) to induce a specific cellular response. In the human peripheral blood mononuclear cell (PBMC) cultures, IGF-1 was capable of inducing a substantial level of IgE production in a dose-dependent manner. It also noticeably upregulated the IL-4-induced or IL-4 plus anti-CD40-induced IgE production. Similarly, the IGF-1-induced IgE production was enhanced by IL-4 or anti-CD40 in an additive manner, which became saturated at high concentrations of IGF-1. Although IGF-1 alone did not induce IgER II (CD23) expression, it augmented the IL-4-induced surface CD23 expression in a manner similar to the action of anti-CD40. These results imply that IGF-1 is likely to utilize common signaling pathways with IL-4 and anti-CD40 to induce IgE and IgER II expression. In support of this notion, we observed that IGF-1 enhanced the IL-4-induced signal transducers and activators of transcription 6(STAT6) activation and independently induced $NF-{\kappa}B$ activation. Both of these bind to the IgE(C) or IgER II (CD23) promoters. Together, our data suggest that IL-4 and IGF-1 work cooperatively to activate STAT6 and $NF-{\kappa}B$. This leads to the subsequent binding of these transcription factors to the $C{\varepsilon}$ and CD23 promoters to enhance the expression of IgE and IgER II. The observed differential ability of IGF-1 on the induction of IgE vs. IgER II is discussed based on the different structure of the two promoters.

• Journal of Life Science
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• v.32 no.2
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• pp.86-93
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• 2022

Lupeol is a type of pentacyclic triterpene and has been reported to have pharmacological activities against various diseases; however, the effect of lupeol on glucose absorption has not been elucidated yet. This study aimed to investigate the effect of lupeol on glucose uptake in 3T3-L1 adipocytes. Lupeol significantly facilitated glucose uptake by translocating glucose transporter type 4 (GLUT4) to the plasma membrane of the 3T3-L1 adipocytes, which was related to activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) and 5 'adenosine monophosphate-activated protein kinase (AMPK) pathways. In the PI3K/AKT pathway, lupeol stimulates the phosphorylation of insulin receptor substrate 1 (IRS-1), which activates PI3K. Its activation by lupeol promotes the phosphorylation of AKT, but not the atypical protein kinase C isoforms ζ and λ. Lupeol also promoted the phosphorylation of AMPK. The activation of AMPK increased the expressions of the plasma membrane GLUT4 and the intracellular glucose uptake. The increase in the glucose uptake by lupeol was suppressed by wortmannin (PI3K inhibitor) and compound C (AMPK inhibitor) in the 3T3-L1 adipocytes. The results indicate that lupeol can facilitate glucose uptake by increasing insulin sensitivity through the stimulation of the expression of plasma membrane glucose transporter type 4 via the PI3K/AKT and AMPK pathways in the 3T3-L1 adipocytes.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.1
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• pp.65-73
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• 2007

In the inverse perturbation method, enormous computational resource was required to obtain reliable results, because all unspecified DOFs were considered as unknown variables. Thus, in the present study, a reduced system method is used to condense the unspecified DOFs by using the specified DOFs, and to improve the computational efficiency as well as the solution accuracy. In most of the conventional reduction methods, transformation errors occur in the transformation matrix between the unspecified DOFs and the specified DOFs. Thus it is hard to obtain reliable and accurate solution of inverse perturbation problems by reduction methods due to the error in the transformation matrix. This numerical trouble is resolved in the present study by adopting iterative improved reduced system(IIRS) as well as by updating the transformation matrix at every step. In this reduction method, system accuracy is related to the selection of the primary DOFs and Iteration time. And both are dependent to each other So, the two level condensation method (TLCS) is selected as Selection method of primary DOFs for increasing accuracy and reducing iteration time. Finally, numerical verification results of the present iterative inverse perturbation method (IIPM) are presented.

• Animal Bioscience
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• v.34 no.4
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• pp.642-651
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• 2021

Objective: This study aimed to determine the effects of different roughages in total mixed ration (TMR) inoculated with or without coculture of Lactobacillus acidophilus (L. acidophilus) and Bacillus subtilis (B. subtilis) on in vitro rumen fermentation and microbial population. Methods: Three TMRs formulations composed of different forages were used and each TMR was grouped into two treatments: non-fermented TMR and fermented TMR (F-TMR) (inoculated with coculture of L. acidophilus and B. subtilis). After fermentation, the fermentation, chemical and microbial profile of the TMRs were determined. The treatments were used for in vitro rumen fermentation to determine total gas production, pH, ammonianitrogen (NH3-N), and volatile fatty acids (VFA). Microbial populations were determined by quantitative real-time polymerase chain reaction (PCR). All data were analyzed as a 3×2 factorial arrangement design using the MIXED procedure of Statistical Analysis Systems. Results: Changes in the fermentation (pH, lactate, acetate, propionate, and NH3-N) and chemical composition (moisture, crude protein, crude fiber, and ash) were observed. For in vitro rumen fermentation, lower rumen pH, higher acetate, propionate, and total VFA content were observed in the F-TMR group after 24 h incubation (p<0.05). F-TMR group had higher acetate concentration compared with the non-fermented group. Total VFA was highest (p<0.05) in F-TMR containing combined forage of domestic and imported source (F-CF) and F-TMR containing Italian ryegrass silage and corn silage (F-IRS-CS) than that of TMR diet containing oat, timothy, and alfalfa hay. The microbial population was not affected by the different TMR diets. Conclusion: The use of Italian ryegrass silage and corn silage, as well as the inoculation of coculture of L. acidophilus and B. subtilis, in the TMR caused changes in the pH, lactate and acetate concentrations, and chemical composition of experimental diets. In addition, F-TMR composed with Italian ryegrass silage and corn silage altered ruminal pH and VFA concentrations during in vitro rumen fermentation experiment.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.313-320
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• 2021

The present study aimed to investigate the effect of whole wheat cookie supplemented with Capsosiphon fulvescens (CF) extract on serum glucose homeostasis in C57BL/6 mice. This study examined whether the same effect was demonstrated for whole wheat cookie in comparison to previous research documenting the glucose-lowering effect of food products combined with CF extract. Mice were divided into three groups depending on the diet administered: normal cookie (NC), whole wheat cookie (WC), and WC blended with CF extract (WCFE). After 4 weeks of administering the experimental diet, the blood glucose level, serum insulin level, and homeostatic model assessment for insulin resistance index were found to be significantly lower in the WCFE group than in the NC and WC groups. These results suggest that whole wheat cookie containing CF extract is effective in preventing insulin resistance and maintaining blood glucose homeostasis.