• 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.

• 한국벤처창업학회:학술대회논문집
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• 2008.04a
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• pp.179-208
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• 2008

In this research, an empirical analysis was performed to determine the correlation between management performance and R&D investment for domestic venture businesses in each industry. Specifically, an empirical analysis for each industry was attempted not only to clarify the general hypothesis on the relationship between management performance and R&D investment for venture businesses but also to demonstrate that differences exist for each industry. Empirical analysis was conducted for eight industries with respect to the $2002{\sim}2006$ panel data extracted as investigative results from the "Investigation Report on Science and Technology R&D Activities" published by the Ministry of Science and Technology. Industrial classification was limited to the middle-level classification (2-digit) in the Korea Standard Industry Code (KSIC) owing to the limited number of panels. Although this research only verified the overall positive effect of R&D activities and funds for existing research on corporate value or productivity and management performance, it was able to document the difference for each individual industry and each business size unlike existing research.Furthermore, the reliability of the research results was enhanced by targeting companies that have been continuously conducting R&D and management activities using consistent 5-year panel data in the analysis. Again, this was something that existing research did not have. Finally, through the use of recent data from 2002 after the IMF economic crisis up to 2006 in the empirical analysis, this research proposed the problems due to the prevailing circumstances at the time of entering the advanced nation stage based on an empirical analysis; the prevailing problems during the pursuit of advanced nation status before the IMF crisis broke out were not tackled. The key empirical analysis yielded several results. First, capital and size of the labor force have a positive correlation with the management performance for the entire company or the venture business. This applies to all eight industries as the subjects of the analysis. Second, although the number of years since a company has been established can have positive or negative correlation with management performance for the entire company or venture business in specific industries, a definite overall trend cannot be identified. Third, R&D investment can be said to have an overall positive effect on corporate management performance. Fourth, the size of the research staff cannot be said to be a factor unilaterally affecting the management performance of the entire company or the venture business. Fifth, the number of years a research institute has been in operation, which was assumed to have a positive effect on the management performance of a company because of the accumulated R&D know-how -- definitely acts as a positive factor contributing to the management performance of a company.

• Clinical and Experimental Pediatrics
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• v.52 no.5
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• pp.544-548
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• 2009

Purpose : To elucidate a potential association between Helicobacter pylori (HP) infection and iron-deficiency anemia (IDA) in infants and children in terms of the other factors related to iron utilization and storage although the association of ferritin was previously studied. Methods : We evaluated 135 infants (aged 6-24 months) admitted at Gyeongsang National University Hospital from 2000 to 2006. Western blot assays using the HP CagA antigen (120 kD) were conducted to identify infections. The concentrations of six parameters were measured: hemoglobin (Hb), serum ferritin, soluble serum transferrin receptors, interleukin-6, prohepcidin, and C-reactive protein. In addition, the infants were classified into IDA, anemia from inflammation (AI), unclassified anemia (UCA), and normal groups on the basis of Hb and ferritin concentrations. Results : In the IDA group (n=20), seven infants were infected with HP, with the other infants showing no evidence of infection. The mean Hb levels in the IDA group were significantly lower in HP-infected infants than those uninfected (7.1 vs. 8.2 g/dL, respectively); the mean ferritin levels were also significantly lower in the infected infants (3.2 vs. $6.8{\mu}g/L$). The other four parameters did not differ significantly among the IDA infants. No correlations were found between the six parameters and HP infection status in the other groups. Conclusion : There were no significant differences in the HP infection rates among the study groups. However, in the IDA group, the HP-infected infants had significantly lower serum ferritin and Hb levels than the HP-negative infants (P<0.05).

• Journal of Nutrition and Health
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• v.49 no.4
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• pp.247-257
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• 2016

Purpose: The aim of this study was to investigate the relationship between instant noodle intake and metabolic factors in Korean adults. Methods: Study subjects were 5,894 (male 2,293, female 3,601) aged 19~64 years who participated in the 2013~2014 KNHANES. Information on frequency and consumption of instant noodles was obtained by the food frequency questionnaires method in KNHANES (Korean National Health and Nutrition Examination Survey), and subjects were classified according to age, sex, and instant noodle consumption (INC). Results: The frequency and consumption of instant noodles was 1.2 times/week and 1.2 servings in subjects. High INC group (${\geq}1$ serving/week) was significantly younger in age compared with the low INC group (< 1 serving/week). However, the high INC group had significantly higher waist circumference, metabolic factors (triglyceride, cholesterol, and HDL-cholesterol), and dietary intake (energy intake, fat, and sodium density) compared with the low INC group. Hyperglycemia showed association with higher risk of highest quartile of INC after adjustments for multiple confounding factors, including age, gender, household income, education, smoking, and alcohol compared with the lowest quartile (OR: 1.4, 95% CI: 1.1-1.8). In female, abdominal obesity showed association with higher risk of highest quartile of INC after adjustments for multiple confounding factors compared with the lowest quartile (OR: 1.6, 95% CI: 1.2-2.2). Conclusion: Consumption of instant noodles was associated with increased prevalence of abdominal obesity and hyperglycemia in women. These findings suggest an association of instant noodle consumption status with metabolic risk.

• Journal of Nutrition and Health
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• v.40 no.4
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• pp.334-346
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• 2007

The present study examined the reproductive factors and food intake pattern which influence on the breast cancer risk in Daegu${\cdot}$Gyungbuk area. The case subjects were 103 patients newly diagnosed as breast cancer at Kyungpook National University Hospital. The control subjects were 159 healthy women selected by frequency matching of age and menopausal status in the same community. The survey was conducted by individual interviews using questionnaires which include general and reproductive characteristics, dietary habits, and food frequency. The odds ratios were calculated by using unconditional logistic regression after adjusting for confounding variables. The mean age of the subjects was 50 yrs, and mean body mass index was significantly high in the patient group than in the control. The patient group had a significantly higher familial history of breast cancer and a significantly shorter breast-feeding period compared to the control group. It has been found no significant relationship between extrinsic hormone use such as oral contraceptives or estrogen replacement therapy and breast cancer risk. In regard of food habits, a high preference for the cooking method of steaming rather than frying, panbroiling or roasting was significantly associated with lower relative risk of breast cancer. The higher intake frequencies of fruits for all subjects, and seaweeds only for postmenopausal subjects were related with a significantly lower relative risk of breast cancer. The results of the study suggest that the possible risk factors for the breast cancer occurrence include high BMI, family history, less breast feeding experience, preference for the cooking method of frying, and less consumption of fruits and seaweeds. This study provides an useful data for nutrition education to prevent breast cancer for the residents in Daegu${\cdot}$Gyungbuk area.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.1
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• pp.31-42
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• 2014

Purpose: The present study was conducted to investigate the effect of the physical properties of RGP lens induced by lens polishing on the actual wearer's subjective comfort, the tear film break-up time and the blinking rate as a follow-up study that revealed the relationship between the lens physical properties during lens manufacturing and lens wearer's factors. Methods: RGP lenses made from the three different polishing conditions (25, 50 and 100 seconds) were applied on 28 eyes of 17 subjects, aged 20 to 29 years, without any known disease and surgical history in the eyes. While the subjects were asked to wear the RGP lenses longer than a week, the questionnaire for the comfortability was administered everyday. Subjective and objective tear break-up time and blinking rate of the wearers were further measured. Results: The wearer's subjective comfortability showed some difference in the type of discomfort and satisfaction score according to the polishing status when wearing RGP lenses made from different polishing conditions longer than a week, and a bigger difference in satisfaction score induced by polishing condition was especially shown in experienced RGP lens wearer rather than un-experienced wearer. In the case of RGP lens wearer compared with the ones without the wearing experience, as the wearing time increased subjective and objective tear break-up time were increased and the blinking rate was decreased. However, subjective and objective tear break-up time were tended to decrease with even longer wearing time when wearing the RGP lens made from the polishment for 100 seconds. Conclusions: These results confirmed that the optimization of physical properties of the lens may not give the same effect on the wearer's subjective and objective symptoms and other factors when actual wearing. From the results, it can suggest that the success rate of RGP lens wear may be changed by physiological factors such as the stabilization of wearer's tear film, comfortability and lens wearing experience when wearing RGP lens based on 'The manufacturing standard for soft contact lens/hard contact lens' provided by Korea Food and Drug Administration.

• Journal of Korean Society of Forest Science
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• v.60 no.1
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• pp.17-23
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• 1983

Total 83model forest owners in Korea were investigated to find out the relationship between their attitudes toward tree felling (or propensity to felling) and selected six independent variables, i.e, owner's age(X1), educational level(X2), forest land area (X3), socioeconomic status (X4), communication (X5) and sociopsychological factor(X6). The dependent variable was measured by Liken attitude scale, and analyzed by multiple regression. Major findings of the study are summarized as follows: 1) The degree of the propensity of felling is relatively high. The communication and sociopsychological variables are negatively, but education level is positively related to the dependent variable. 2) The multiple correlation coefficient between felling-attitude score and six independent variables is 0.5322. Of the variance of this sttitude score, about 13 percent can be explained by communication variable, 6 percent by sociopsychological variable and other 6 percent by age variable. 3) The model owners' attitudes toward felling are positively correlated with there sources of communication variable, i.e. personal contact, social participation and mass media contact. The multiple correlation coefficient between felling-attitude score and three sources of communication variable is 0.4049. This means that 16 percent of the variance of the attitude score can be explained by three sources of communication, that is, 9 percent by personal contact, 5 percent by social participation and 3 percent by mass media. 4) The fatalistic, untrustful and non-ambitious personalities were positively, but conservative personality negatively related to the propensity to tree felling. The multiple correlation coefficient between seven different personalities and the dependent variable is 0.5461. Of the variance of the dependent variable, 11 percent can be explained by untrustful personality, and other 11 percent by nonambitious personality.

• Development and Reproduction
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• v.13 no.4
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• pp.207-215
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• 2009

Numerous factors can affect the activities of hypothalamus-pituitary-gonad (HPG) hormonal axis, resulting in alteration of reproductive capacity or status such as onset of puberty and menopause. Soon after the finding of leptin, a multifunctional hormone secreted from adipocytes, a close relationship between reproduction and body energy balance have been manifested. Ghrelin, another multifunctional hormone from gastrointestinal tract, is an endogenous ligand of growth hormone secretagogue receptor (GHSR), and is thought to be a counterpart of leptin in the regulation of energy homeostasis. As expected, ghrelin can also modulate the reproductive capacity through the modulation of activities of HPG axis. This paper summarizes the current knowledge on the discovery, gene structures, tissue distribution and roles of ghrelin and GHSRs in mammalian reproduction in particular modulation of reproductive hormone secretion in HPG axis. Like POMC gene expression in pituitary gland, preproghrelin gene can generate a complex repertoire of transcripts which further undergo alternative splicing and posttranslational modifications. Concerning the roles of preproghrelin gene products in the control of body physiology except energy homeostasis, limited knowledge is available so far. Several lines of evidence, however, show the interplay of ghrelin between metabolism and reproduction. In rat and human, the distribution of ghrelin receptor GHSRs (GHSR1a and GHSR1b) has been confirmed not only in the hypothalamus and pituitary which were originally postulated as target of ghrelin but also in the testis and ovary. Expression of the preproghrelin gene in the brain and gonads was also verified, suggesting the local role (s) of ghrelin in HPG axis. Ghrelin might play a negative modulator in the secretions of hypothalamic GnRH, pituitary gonadotropins and gonadal steroids though the action on pituitary is still questionable. Recent studies suggest the involvement of ghrelin in regulation of puberty onset and possibly of menopause entry. It is now evident that ghrelin is a crucial hormomal component in 'brain-gut' axis, and is a strong candidate links between metabolism and reproduction. Opposite to that for leptin, ghrelin signaling is likely representing the 'hunger' state of body energy balance and is necessary to avoid the energy investment into reproduction which has not a top priority in maintaining homeostasis. Further researches are needed to gain a deep insight into the more precise action mechanism and role of ghrelin in reproduction, and to guarantee the successful biomedical applications.

• Korean Journal of Environmental Agriculture
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• v.20 no.2
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• pp.127-132
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• 2001

This study was conducted for ten years to evaluate the effective soil management for preventing the infection of root-knot nematode in the field of continuous cultivation with oriental melon under plastic house in Songju area of kyongbuk province. The content of available phosphate, total nitrogen, organic matter, CEC, and exchangeable base in the soil increased with the increase of continuous cultivation year. Especially salt content in the soil increased form 1.2 to 4.55 mS/cm and the yield of oriental melon dramatically decreased with the continuous cultivation year. The number of root-knot nematode was 91 per $300\;cm^3$ of soil in the field of continuous cultivation for 3 years and showed slight damage on the oriental melon, but it was 518 in the field of $4{\sim}6$ years continuous cultivation and showed that 50% of plants died in August, and the yield of late season was less than 50% compared to normal plant. For the seasonal changes in infection rate of root-knot nematode on oriental melon plant, 15% of the normal plant was infected by nematode in February and increased gradually by $10{\sim}20%$ per month, 60% of plants was infected in July. The density of root-knot nematode nymph was 167 in February and increased to 1,625 in August. The infection rate of nematode was 35%, and the number of nematode was about 54 in nursery soil originated from paddy soil, upland soil, and river sand. There were no relationship between the number of nematode and available phosphate or exchangeable base in the soil of plastichouse where oriental melon plants were grown.

• Journal of Preventive Medicine and Public Health
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• v.25 no.1 s.37
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• pp.1-12
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• 1992

To assess the pattern of psychiatric symptoms and to evaluate the relationship between exposure related variables(duration of work and urinary hippuric acid concenturation) and psychiatric symptoms in organic solvent exposed workers, case control study of forty-two solvent exposed workers and ninethy-six non-exposed workers was conducted. The general health questionnaire 28(GHQ28) was administered to evaluate psychiatric symptoms and urinary hippuric acid concenturations was measured to estimate the present status of solvent exposure in exposed group and to estimate normal level in non-exposed group. The mean concenturation of urinary hippuric acid was significantly higher in exposed group (2.953g/creatinine g) than non-exposed group(0.395g/creatinine g) (P<0.01). The total positive rates of symptoms were significantly higher in exposed group(28.2%) than non-exposed group(17.5%)(P<0.05). The positive rates of symptoms for four sub-scales of GHQ28 in exposed group were in the order of somatic symptoms, anxiety, social dysfunction, depression and in the order of social dysfunction, anxiety, depression, somatic symptoms in non -exposed group. The positive rates of symptoms for somatic symptoms and anxiety were significantly higher in exposed group than non-exposed group (P<0.05) and the proportion of workers with six or more positive symptoms(dysthymic states) in exposed group were significantly higher than non-exposed group (P<0.01). After the effect of age, sex, level of income, level of education, and duration of work were controlled, the total score of GHQ28 was still significantly different between exposed and non-exposed group(P<0.01). In multipile logistic regression analysis on the dysthymic state, the odds ratio of level of income was statictically significant in both group. The odds ratios of exposure related variables such as duration of work and hippuric acid concenturations were not statistically significant but there was a tendency that exposure related variables had an affect on dysthymic state in exposed group. In future, continuous evaluation of psychiatric symptoms on organic solvent exposed workers and studies to detect the factors that affect on psychiatric symptoms are required.