• Korean Journal of Biological Psychiatry
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• 제11권2호
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• pp.104-109
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• 2004

Objectives:Abnormalities in neurotrophic factors that regulate neuronal development and synaptic plasticity are often implicated as some causes of schizophrenia. In previous studies, researchers reported that brain and serum BDNF levels underwent similar changes during maturation and aging processes in rats. They also found a positive correlation between serum and cortical BDNF levels. In this study, we investigated whether the serum levels of BDNF in Korean schizophrenic patients would be different from those of healthy controls. Methods:Using an ELISA kit, serum BDNF levels were assessed in schizophrenic group(N=49) and control group(N=50). Results:Serum BDNF levels in the schizophrenic group($36.29{\pm}19.78$ng/ml) were significantly higher than those in control group($22.4{\pm}14.4$ng/ml). The BDNF levels did not correlate with duration of treatment, age or daily dose of antipsychotics in patients with schizophrenia. Conclusions:This result suggests that schizophrenia is characterized by high serum BDNF levels and supports the hypothesis of neurotrophic factor involvement in psychotic disorder. Serum BDNF level is likely to be one of the possible biological markers for schizophrenia.

• Environmental Analysis Health and Toxicology
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• 제4권1_2호
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• pp.55-65
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• 1989

Nevertheless the serious environmental pollution in Korea has been discussed in concern with health effect, the significant effect are not determined easily. Toxicological method has been used to establish safe levels of exposure for environmental pollutants to have threshold health effect below which significant effects are unlikely to occur. However the conventional method cannot to establish safe levels of exposure for non-threshold pollutants have been used to express comprehensive pollution degree, not in detailed toxic effects. Acceptable exposure or risk levels are decides by policymakers who consider descriptions and estimates of risks together with social and economic benefits. This paper focuses on the concept development of risk assessment and describes some risks of environmental pollution based on the surveyed date in Korea. The current concepts of risk assessment in policy descisions can be explored and areas for possible improvement, given current scientific knowledge are identified. The experience of foreign countries can provide a realistic basis for evaluating the existing data of environmental pollutants. To improve the environmental quality, risk regulation should be managed as soon as possible in Korea.

• Journal of Korean Academy of Nursing
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• 제37권6호
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• pp.986-993
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• 2007

Purpose: The purpose of this study was to compare stress levels of elementary students according to three regional levels: a large city, a medium-sized city, and a rural area. Methods: This was a descriptive comparative survey using a convenience sample of 1,161 5th-and 6th-grade students. The stress level was measured by a stress scale that consisted of 65 items regarding personal characteristics, family, school, and peer factors. The data were analyzed by ${\chi}^2-test$, t-test, ANOVA and multiple regression using the SPSS 10.0 statistical program. Results: Overall, the mean stress scores reported by the participants were near the middle of a 5-point scale and the level of family-related stress was highest, followed by peer, school, and individual-related stress. Sixth-graders and female students showed higher stress levels than 5th-graders and male students, respectively. The participants reporting unsatisfaction with their lives and those living in large cities tended to have significantly higher stress levels. Conclusion: Grade, gender, life satisfaction, and regional levels were all significant factors associated with high stress levels among elementary students. Development of stress management programs for this specific population, especially targeting students who are female and living in large cities, is needed.

• Preventive Nutrition and Food Science
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• 제21권3호
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• pp.171-180
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• 2016

Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent liver diseases associated with an altered lifestyle, besides genetic factors. The control and management of NAFLD mostly depend on lifestyle modifications, due to the lack of a specific therapeutic approach. In this context, we assessed the effect of carrot juice on the development of high fructose-induced hepatic steatosis. For this purpose, male weanling Wistar rats were divided into 4 groups, fed either a control (Con) or high fructose (HFr) diet of AIN93G composition, with or without carrot juice (CJ) for 8 weeks. At the end of the experimental period, plasma biochemical markers, such as triglycerides, alanine aminotransferase, and ${\beta}$-hydroxy butyrate levels were comparable among the 4 groups. Although, the liver injury marker, aspartate aminotransferase, levels in plasma showed a reduction, hepatic triglycerides levels were not significantly reduced by carrot juice ingestion in the HFr diet-fed rats (HFr-CJ). On the other hand, the key triglyceride synthesis pathway enzyme, hepatic stearoyl-CoA desaturase 1 (SCD1), expression at mRNA level was augmented by carrot juice ingestion, while their protein levels showed a significant reduction, which corroborated with decreased monounsaturated fatty acids (MUFA), particularly palmitoleic (C16:1) and oleic (C18:1) acids. Notably, it also improved the long chain n-3 polyunsaturated fatty acid, docosahexaenoic acid (DHA; C22:6) content of the liver in HFr-CJ. In conclusion, carrot juice ingestion decreased the SCD1-mediated production of MUFA and improved DHA levels in liver, under high fructose diet-fed conditions. However, these changes did not significantly lower the hepatic triglyceride levels.

• Journal of the Korean Society of Physical Medicine
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• 제18권2호
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• pp.13-21
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• 2023

PURPOSE: This study examined the specific clinical risk factors in middle-aged men with age-related loss of skeletal muscle mass (ALSMM). METHODS: The present research analyzed the data from a cross-sectional study of 1,564 community-dwelling participants aged between 40 to 49 years old. The participants were screened for ALSMM. The study examined various risk factors, including age, height, weight, body mass index, waist circumference, skeletal muscle mass index, smoking and drinking status, systolic and diastolic blood pressure, fasting glucose levels, and triglyceride and cholesterol levels. RESULTS: The risk factors of ALSMM were height, body mass index, waist circumference, skeletal muscle mass index, systolic blood pressure, diastolic blood pressure, drinking status, fasting glucose, and triglyceride levels (p < .05). The weight, triglyceride, and smoking status variables were non-significant (p > .05). CONCLUSION: The risk factors for ALSMM among community-dwelling adults were determined. These results are expected to contribute to the existing literature on ALSMM and provide potential risk factors associated with the development of ALSMM in middle-aged males.

• Clinical and Experimental Reproductive Medicine
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• 제13권2호
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• pp.101-112
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• 1986

It is now common practice to attempt ovarian hyperstimulation in vitro fertilization and embryo transfer (IVF-ET) to promote the development of multiple preovulatory follicles and to maximize the number of mature egg available. There are several drugs for hyperstimulation such as clomiphene citrate only, clomiphene citrate and human menopausal gonadotropin (HMG) and HMG only. Accumlated experience has shown that the hyperstimulation of the ovary in IVF-ET results in high pregnancy rate. But the hyperstimulation of the ovary in IVF-ET may cause the hyperandrogenism, so we must consider the adverse effect on pregnancy rate of the hyperandrogenism. Little is known about the functional significance of androgen for the follicular growth, however, the hyperandrogenism might interfere with oocyte maturation. The aim of the present investigation was to determine the serum profiles of estradiol, androstenedione and testosterone during the hyperstimulated menstrual cycles in IVF. The results were summarized as follows: 1. There was a gradual increase in the mean levels of serum estradiol, androstenedione, and testosterone approaching follicular maturation. 2. The mean serum estradiol levels in the hyperstimulated groups were significantly higher than that in the control group in late follicular phase and ovum retrieval (ovulation) day (p<0.01). 3. The mean serum androstenedione levels in the clomiphene citrate groups were significantly higher than that in the control group in late follicular phase (p<0.01). There was no statistically significant different in the mean serum androstenedione levels between the control group and the HMG group (p>0.05). 4. There was no statistically significant difference in the mean levels of testosterone among each group (p>0.05). 5. There was no statistically significant different in the mean levels of estradiol, androstenedione and testosterone between the fertilized patients and non-fertilized patients in clomiphene citrate and HMG group (p>0.05).

• Nutrition Research and Practice
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• 제9권5호
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• pp.503-510
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• 2015

BACKGROUND/OBJECTIVES: Increased serum homocysteine (Hcy) levels have been reported to be related to the occurrence of cardio- and cerebrovascular diseases. High serum Hcy levels are also related to the development of secondary stroke and all-cause mortality. The purpose of this study was to investigate the prevalence of high serum homocysteine level and relating factors, and the change over the 10 month period post-stroke. SUBJECTS/METHODS: Consecutive stroke patients who were admitted to the Asan Medical Center were enrolled. Ten months after the onset of stroke, an interview with a structured questionnaire was performed and blood samples were obtained for the biochemical parameters. Nutritional status was determined using the mini nutritional assessment (MNA) score and dietary nutrient intakes were also obtained using a 24 hour recall method. RESULTS: Out of 203 patients, 84% were malnourished or at risk of malnutrition, and 26% had high homocysteine levels at 10 months post-stroke. Using logistic regression, the factors related with high homocysteine levels at 10 months post-stroke included heavy alcohol consumption (P = 0.020), low MNA scores (P = 0.026), low serum vitamin $B_{12}$ (P = 0.021) and low serum folate levels (P = 0.003). Of the 156 patients who had normal homocysteine levels at admission, 36 patients developed hyperhomocysteinemia 10 months post-stroke, which was related to heavy alcohol consumption (P = 0.013). Persistent hyperhomocysteinemia, observed in 22 patients (11%), was related to male sex (P = 0.031), old age (P = 0.042), low vitamin $B_6$ intake (P = 0.029), and heavy alcohol consumption (P = 0.013). CONCLUSION: Hyperhomocysteinemia is common in post-stroke, and is related to malnutrition, heavy alcohol drinking and low serum level of folate and vitamin $B_{12}$. Strategies to prevent or manage high homocysteine levels should consider these factors.

• Child Studies in Asia-Pacific Contexts
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• 제6권1호
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• pp.17-29
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• 2016

To help define future research direction and enhance educational service for children from Asian and Latino immigrant backgrounds, this review examines research investigating social competence with reference to host and heritage language skills. A targeted search obtained 14 peer-reviewed studies published from 1994 to 2014 focusing on children aged from birth to 12 years. Social competence is mainly measured by four dimensions: externalizing behaviours, internalizing behaviours, social skills and relationships with others. The evidence suggests that English proficiency levels are positively associated with social skills and parent-child relationships are of higher quality when parent-child heritage language difference is minimal. However the findings are mixed regarding how English levels are associated with externalizing, internalizing behaviours and relationships with others and how heritage language levels are associated with social competence. This review makes a set of recommendations for future research including assessment of participants' language proficiency with language tests and examination of emotional factors in the relationship between English and social competence. The implications of the findings are also discussed for educators.

• Animal Bioscience
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• 제36권7호
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• pp.1022-1033
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• 2023

Objective: p66Shc, a 66 kDa protein isoform encoded by the proto-oncogene SHC, is an essential intracellular redox homeostasis regulatory enzyme that is involved in the regulation of cellular oxidative stress, apoptosis induction and the occurrence of multiple age-related diseases. This study investigated the expression profile and functional characteristics of p66Shc during preimplantation embryo development in sheep. Methods: The expression pattern of p66Shc during preimplantation embryo development in sheep at the mRNA and protein levels were studied by quantitative real-time polymerase chain reaction (RT-qPCR) and immunofluorescence staining. The effect of p66Shc knockdown on the developmental potential were evaluated by cleavage rate, morula rate and blastocyst rate. The effect of p66Shc deficiency on reactive oxygen species (ROS) production, DNA oxidative damage and the expression of antioxidant enzymes (e.g., catalase and manganese superoxide dismutase [MnSOD]) were also investigated by immunofluorescence staining. Results: Our results showed that p66Shc mRNA and protein were expressed in all stages of sheep early embryos and that p66Shc mRNA was significantly downregulated in the 4-to 8-cell stage (p<0.05) and significantly upregulated in the morula and blastocyst stages after embryonic genome activation (EGA) (p<0.05). Immunofluorescence staining showed that the p66Shc protein was mainly located in the peripheral region of the blastomere cytoplasm at different stages of preimplantation embryonic development. Notably, serine (Ser36)-phosphorylated p66Shc localized only in the cytoplasm during the 2- to 8-cell stage prior to EGA, while phosphorylated (Ser36) p66Shc localized not only in the cytoplasm but also predominantly in the nucleus after EGA. RNAi-mediated silencing of p66Shc via microinjection of p66Shc siRNA into sheep zygotes resulted in significant decreases in p66Shc mRNA and protein levels (p<0.05). Knockdown of p66Shc resulted in significant declines in the levels of intracellular ROS (p<0.05) and the DNA damage marker 8-hydroxy2'-deoxyguanosine (p<0.05), markedly increased MnSOD levels (p<0.05) and resulted in a tendency to develop to the morula stage. Conclusion: These results indicate that p66Shc is involved in the metabolic regulation of ROS production and DNA oxidative damage during sheep early embryonic development.

• New & Renewable Energy
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• 제19권1호
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• pp.41-52
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• 2023

Various carbon upcycling technologies have been proposed and are under development to achieve Korea's carbon neutrality target. Many chemical reactions are under development through various chemical reaction pathways, and different technological maturity levels are shown for each country and company. In this situation, it is essential to establish investment decisions such as research funds and human resources allocation through technological and economic analysis for close commercialization technologies and basic technologies with low technology readiness levels (TRL). Therefore, in this study, the technology development priority for developing carbon upcycling items was selected according to the domestic Carbon Capture & Utilization (CCU) technology roadmap using the stakeholder selection tool released by EU CarbonNext. As a result of the analysis, the TRL level of Korea's major carbon upcycling technologies was analyzed to be lower than that of other carbon resource technologies, and it was considered desirable to invest in mineral carbonization technologies among various candidate technologies.