• Journal of Nutrition and Health
• /
• v.36 no.3
• /
• pp.255-261
• /
• 2003

Food irradiation has been steadily increasing in many countries in line with increasing international trade and concerns about naturally occurring harmful contaminants in food. Although irradiation provides an excellent safeguard for the consumer by destroying almost 100% of harmful bacteria, it is necessary to ensure the safety of irradiated foods. This study was performed to investigate the effect of an irradiated diet on lipid peroxidation in the plasma, liver, small intestinal mucosa, and lymphocyte DNA damage in mice. Eight-week old ICR mice were assigned to two groups to receive either non-irradiated or irradiated (10 kGy) diets containing 20.38% fish powder and 6.06% sesame seeds for 4 weeks. The resulting changes in the degrees of lipid peroxidation were evaluated based on the level of plasma and liver thiobarbituric acid reactive substance (TBARS), transmission electron micrograph of jejunal mucosa, and free radical-induced oxidative DNA damage in lymphocytes, as measured by alkaline comet assay (single cell gel electrophoresis). The peroxide values of the gamma irradiated diet were measured every week, and the sample for comet assay was taken at the end of the four week experimental period. There was no significant difference in food efficiency ratio between the two groups. The peroxide values of the diet were immediately increased to 35.5% after gamma irradiation and kept on increasing during storage. After 4 weeks, no differences in tissue or plasma TBARS value were observed between the two groups, but epithelial cells of jejumum showed osmiophillic laminated membranous structures, considered as myelin figures,. The oxidative DNA damage expressed as tail moment (TM) increased 30% in the blood lymphocytes of the mice fed the irradiated diet. In conclusion, the comet assay sensitively detected differences in lymphocyte DNA damage after feeding with the irradiated diet for 4 weeks. However, in order to ensure the safety of irradiated foods, it would be more useful to conduct a long-term feeding regimen using an irradiated diet and examine the level of lipid peroxidation and the state of oxidative stress in a greater range of organs.

• Molecules and Cells
• /
• v.37 no.12
• /
• pp.865-872
• /
• 2014

Premature ovarian failure (POF) is a long-term adverse effect of chemotherapy treatment. However, current available treatment regimens are not optimal. Emerging evidence suggests that bone marrow-derived mesenchymal stem cells (BMSCs) could restore the structure and function of injured tissues, but the homing and restorative effects of BMSCs on chemotherapy injured ovaries are still not clear. In this study, we found that granulosa cell (GC) apoptosis induced by cisplatin was reduced when BMSCs were migrated to granulosa cells (GCs) in vitro. Chemotherapy-induced POF was induced by intraperitoneal injection of cisplatin in rats. BMSCs labeled with enhanced green fluorescent protein (EGFP) were injected into the rats via the tail vein to investigate the homing and distribution of BMSCs in vivo. The number of BMSCs in the ovarian hilum and medulla was greater than in the cortex, but no BMSCs were found in the follicles and corpus lutea. In addition, the BMSCs treatment group's antral follicle count and estradiol levels increased after 30 days, compared with the POF group. Hence, our study demonstrates that intravenously delivered BMSCs can home to the ovaries, and restore its structure and function in POF model rats.

• Korean Journal of Materials Research
• /
• v.13 no.4
• /
• pp.233-238
• /
• 2003

Ferromagnetic tunnel junctions, Ta/Cu/Ta/NiFe/Cu/$Mn_{75}$ $Ir_{25}$ $Co_{70}$ $Fe_{30}$/Al-oxide, were fabricated by do magnetron sputtering and plasma oxidation process. The effect of annealing temperature on the local transport properties of the ferromagnetic tunnel junctions was studied using contact-mode Atomic Force Microscopy (AFM). The current images reflected the distribution of the barrier height determined by local I-V analysis. The contrast of the current image became more homogeneous and smooth after annealing at $280^{\circ}C$. And the average barrier height $\phi_{ave}$ increased and its standard deviation $\sigma_{\phi}$ X decreased. For the cases of the annealing temperature more than $300^{\circ}C$, the contrast of the current image became large again. And the average barrier height $\phi_{ave}$ decreased and its standard deviation $\sigma_{\phi}$ increased. Also, the current histogram had a long tail in the high current region and became asymmetric. This result means the generation of the leakage current that is resulted from the local generation of a low barrier height region. In order to obtain the high tunnel magnetoresistance(TMR) ratio, the increase of the average barrier height and the decrease of the barrier height fluctuation must be strictly controlled.led.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.12
• /
• pp.4752-4759
• /
• 2010

Using Technology Acceptance Model and flow theory as our foundation, this paper investigates the interrelationships among social influence, individual cognition, flow, and actual usage in the Web 2.0 environment. According to TAM, users evaluate perceived usefulness(PU) and ease of use(PEU) of information technology(IT) in accepting the innovative IT. Along with users' cognitive evaluation(i.e. PU and PEU), in case of UCC(user-created-contents), which is one of the representative Web 2.0 features, flow also has a significant effect on users' usage. Accordingly, the current study involve cognitive elements such as PU and PEU as well as flow of enjoyable state during using IT in exploring antecedents leading to UCC usage. On one hand, we consider the effect of social influence on users' cognition and flow toward actual usage because the more users creates Web contents, the more long-tail situation prevails on the Internet. Web 2.0 becomes a kind of social phenomena. The empirical results show that social influence affects positively both PU/PEU and flow. Users' cognitive evaluation and flow have positive impacts on users' UCC usage.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.1
• /
• pp.139-143
• /
• 2014

Although correlations between platelets and lung cancer has been recognized, effects on non-small cell lung cancer (NSCLC) metastasis remain to be determined in detail. In the present study, wound healing assays revealed a role of platelets in NSCLC cell migration. Thus the mean migration rate of lung adenocarcinoma A549 cells was significantly elevated after co-culture with platelets ($81.7{\pm}0.45%$ vs $41.0{\pm}3.50%$, P<0.01). Expression of GAPDH was examined by reverse transcription-polymerase chain reaction to study the effect of platelets on NSCLC cell proliferation. The result showed that the proliferation of A549 and SPC-A1 cells was not affected. Mouse models were established by transfusing A549 cells and SPC-A1 cells into mice lateral tail veins. We found tumor metastasis nodules in lungs to be increased significantly after co-transfusion with platelets (in A549, $4.33{\pm}0.33$ vs $0.33{\pm}0.33$, P=0.01; in SPC-A1, $2.67{\pm}0.33$ vs $0.00{\pm}0.00$, P=0.01). In addition, consecutive inoperable patients with newly diagnosed NSCLC (TNM stage III or IV) between January 2009 and December 2011 were retrospectively reviewed. Using the Kaplan-Meier method, NSCLC patients with a high platelet counts demonstrated a significantly shorter progression free survival compared with those with a low platelet count (> $200{\times}10^9/L$, 3 months versus ${\leq}200{\times}10^9/L$, 5 months, P=0.001). An elevated platelet count was also identified as an independent prognostic factor by Cox regression analysis for prgression free survival (adjusted hazard ratio: 1.69; 95% CI: 1.16, 2.46; P=0.006). This study suggested that platelets might contribute to the hematogenous metastatic process by promoting cancer cell migration, which eventually affects the prognosis of NSCLC.

• Journal of Yeungnam Medical Science
• /
• v.19 no.1
• /
• pp.39-48
• /
• 2002

Background: The treatment of rheumatoid arthritis still depend on conserve therapy in major. Recent studies report that n-3 polyunsaturated fatty acids(PUFA) could modulate the incidence and progress of arthritis. The purpose of this study was to investigate the effects of n-3 PUFA on the development of collagen-induced arthritis in rats. Materials and Methods: Female Louvain rats were used for this experiment. Rats were randomly assigned into either normal (n=8) or collagen-immunized groups, and collagen immunized groups were divided into control(n=8, normal diet) and n-3 PUFA(n=8, 5% n-3 PUFA in diet) groups. One week after feeding n-3 PUFA to rats, they were immunized with type II collagen emulsified in incomplete Freund's adjuvant into tail and back. Development of arthritis was confirmed by x-ray and microscopic examination. Results: Incidence of arthritis at the 5th week after immunization was 38% in control and 0% in n-3 PUFA. Rats with arthritis showed edema in hind paws and inflammation in synovial membrane of the knee joint. Plasma glucose and insulin were not changed by both of immunization and diet. Plasma triglycerides and cholesterol concentrations were decreased by n-3 PUFA. Conclusion: n-3 PUFA may prevent or treat collagen-induced arthritis m rats. Further studies are needed for action mechanism of it.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.5
• /
• pp.82-90
• /
• 2018

The nuclear structures are composed of large diameter bars over No.36. If the hooked bars are used for anchorage of large diameter bars, too long length of the tail extension of the hook plus bend create congestion and make an element difficult to construct. To address those problems, headed bars were developed. Provisions of ACI 318-08 specify the development length of headed bars and ignore the effect of transverse reinforcement based on the background researches. However, if headed bars are used at the cut-off or lap splice, longitudinal reinforcements, which are deformed in flexural members, induce tensile stress in cover concrete and increase the tensile force in the transverse reinforcement. The object of this research is to evaluate the effects of transverse reinforcement on the anchorage capacity of headed bar so anchorage test with variable of transverse rebar spacing was conducted. Specimens, which can consider the behavior at the cut-off, were tested. Test results show that failure of specimen without transverse reinforcement was sudden and brittle with concrete cover lifted and developed stress of headed bars was less than half of yield strength of headed bars. On the other hand, in the specimen with transverse reinforcement, transverse rebar directly resist the load of free-end so capacity of specimens highly increased.

• Korean Journal of Food Science and Technology
• /
• v.33 no.6
• /
• pp.795-801
• /
• 2001

Effects of Mucilage fraction from Yam (Dioscorea batatas DECENE), which has long been used as a wild vegetable and folk medicine, on blood glucose and lipid composition in alloxan-induced diabetic mice were investigated. Diabetes mellitus was induced in male ICR mice by the injection of alloxan into the tail vein at a dose of 75 mg/kgBW. Alloxan-induced diabetic mice were administered the yam mucilage fraction1 orally ; y500F1 group (500 mg/kgBW/day fraction1) and y750F1 group (750 mg/kgBW/day fraction1); and the normal and alloxan-control group were orally administered with saline for 10 days. The body weight gain and food intake were monitored every day. The concentrations of glucose, triglyceride, total cholesterol, and LDL-cholesterol of serum and liver levels of glucose, triglyceride, and cholesterol were determined. Also weight of liver, heart, spleen and kidney were measured. The fraction 1 of yam mucilage lowered body weight gain significantly (p<0.05) and decreased serum glucose levels in alloxan-induced diatetic mice compared to that of alloxan-control group. In alloxan induced diabetic mice serum triglyceride level was lowered and liver HDL-cholesterol level increased significantly (p<0.05). In conclusion, it was assumed that yam mucilage fraction 1 has anti-hyperglycemic and anti-obesitic effects by reducing body weight gain and decreasing serum glucose and triglyceride level.

• The Journal of Fisheries Business Administration
• /
• v.40 no.2
• /
• pp.49-70
• /
• 2009

This study proviedes GARCH model(Bollerslev, 1986) to analyze the structural characteristics of price volatility in domestic aquacultural fish market of Korea. As a case study, flatfish and rock-fish are analyzed as major species with relatively high portion in an aspect of production volume among fish captured in Korea. For analyzing, this study uses daily market data (dating from Jan 1 2000 to June 30, 2008) published by the Noryangjin Fisheries Wholesale Market which is located in Seoul of Korea. This study performs normality test on trading volume and price volatility of flatfish and rock-fish as an advanced empirical approach. The normality test adopted is Jarque-Bera test statistic. As a result, first, a null hypothesis that "an empirical distribution follows normal distribution" was rejected in both fishes. The distribution of daily market data of them were not only biased toward positive(+) direction in terms of kurtosis and skewness, but also characterized by leptokurtic distribution with long right tail. Secondly, serial correlations were found in data on market trading volume and price volatility of two species during very long period. Thirdly, the results of unit root test and ARCH-LM test showed that all data of time series were very stationary and demonstrated effects of ARCH. These statistical characteristics can be explained as a reasonable ground for supporting the fitness of GARCH model in order to estimate conditional variances that reveal price volatility in empirical analysis. From empirical data analysis above, this study drew the following conclusions. First of all, from an empirical analysis on potential effects of seasonality and the day of week on price volatility of aquacultural fish, Monday effects were found in both species and Thursday and Friday effects were also found in flatfish. This indicates that Monday is effective in expanding price volatility of aquacultural fish market and also Monday has higher effects upon the price volatility of fish than other days of week have since it has more new information for weekend. Secondly, the empirical analysis led to a common conclusion that there was very high price volatility of flatfish and rock-fish. This points out that the persistency parameter($\lambda$), an index of possibility for current volatility to sustain similarly in the future, was higher than 0.8-equivalently nearly to 1-in both flatfish and rock-fish, which presents volatility clustering. Also, this study estimated and compared and model that hypothesized normal distributions in order to determine fitness of respective models. As a result, the fitness of GARCH(1, 1)-t model was better than model where the distribution of error term was hypothesized through-distribution due to characteristics of fat-tailed distribution, was also better than model, as described in the results of basic statistic analysis. In conclusion, this study has an important mean in that it was introduced firstly in Korea to investigate in price volatility of Korean aquacultural fishery products, although there was partially a limited of official statistic data. Therefore, it is expected that the results of this study will be useful as a reference material for making and assessing governmental policies. Also, it is looked forward that the results will be helpful to build a fishery business plan as and aspect of producer, and also to take timely measures to potential price fluctuations of fishery products in market. Hence, it is advisable that further studies related to such price volatility in fishery market will extend and evolve into a wider variety of articles and issues in near future.