• The Korean Journal of Physiology and Pharmacology
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• v.21 no.6
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• pp.599-607
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• 2017

Most normal cells express L-type amino acid transporter 2 (LAT2). However, L-type amino acid transporter 1 (LAT1) is highly expressed in many tumor cells and presumed to support their increased growth and proliferation. This study examined the effects of JPH203, a selective LAT1 inhibitor, on cell growth and its mechanism for cell death in Saos2 human osteosarcoma cells. FOB human osteoblastic cells and Saos2 cells expressed LAT1 and LAT2 together with their associating protein 4F2 heavy chain, but the expression of LAT2 in the Saos2 cells was especially weak. JPH203 and BCH, a non-selective L-type amino acid transporter inhibitor, potently inhibited L-leucine uptake in Saos2 cells. As expected, the intrinsic ability of JPH203 to inhibit L-leucine uptake was far more efficient than that of BCH in Saos2 cells. Likewise, JPH203 and BCH inhibited Saos2 cell growth with JPH203 being superior to BCH in this regard. Furthermore, JPH203 increased apoptosis rates and formed DNA ladder in Saos2 cells. Moreover, JPH203 activated the mitochondria-dependent apoptotic signaling pathway by upregulating pro-apoptotic factors, such as Bad, Bax, and Bak, and the active form of caspase-9, and downregulating anti-apoptotic factors, such as Bcl-2 and Bcl-xL. These results suggest that the inhibition of LAT1 activity via JPH203, which may act as a potential novel anti-cancer agent, leads to apoptosis mediated by the mitochondria-dependent intrinsic apoptotic signaling pathway by inducing the intracellular depletion of neutral amino acids essential for cell growth in Saos2 human osteosarcoma cells.

• The Korean Journal of Physiology
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• v.11 no.1
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• pp.37-44
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• 1977

In the previous study of the release, excretion, and plasma concentration of aldosterone in normal Koreans, the author found that urinary aldosterone excretion and aldosterone secretion rate of the Korean who usually take high amount of salt are significantly lower, in compared to Americans, although the plasma concentration is only tended to be low. The control of plasma aldosterone level depends on the secretion rate and the metabolic clearance of the hormone. In this experiments, the metabolic clearance rate of aldosterone was determined in normotensive korean and the effects of adrenal stimulations on the rates were also studied in the same subjects. The metabolic clearance rate of the normal Korean was not significantly different from those of the American, and shown a little increase in response to sodium restriction. These results indicate that the decrease in secretion rate rather than the increase in metabolic clearance Tate is the major factor maintaining lower plasma aldosterone level. After furosemide diuresis, on the contrary, the removal of aldosterone showed significant the decrease despite slight increase of secretion rate. This suggest that the reduction in metabolic clearance rate of the hormone during volume depletion found to be major cause of high plasma concentration. Additional potassium supply produced detectable decrease of metabolic clearance rate, but the changes were smaller than that of secretion rate, which suggested that the higher secretion rate could account for elevated plasma concentration of aldosterone rather than metabolic clearance. Above results also support author's previous evidences that the normal Korean who already adapted to a high sodium diet have ability to produce adequate aldosterone activity without producing detectable changes on the metabolic clearance rate under the condition of sodium restriction with approp riate potassium intake.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.960-967
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• 2011

Tannin acyl hydrolase, also known as tannase, is an enzyme with important applications in the food, feed, pharmaceutical, and chemical industries. However, despite a growing interest in the catalytic properties of tannase, its practical use is very limited owing to high production costs. Several studies have already demonstrated the advantages of solid-state fermentation (SSF) for the production of fungal tannase, yet the optimal conditions for enzyme production strongly depend on the microbial strain utilized. Therefore, the aim of this study was to improve the tannase production by a locally isolated A. niger strain in an SSF system. The SSF was carried out in packed-bed bioreactors using polyurethane foam as an inert support impregnated with defined culture media. The process parameters influencing the enzyme production were identified using a Plackett-Burman design, where the substrate concentration, initial pH, and incubation temperature were determined as the most significant. These parameters were then further optimized using a Box-Behnken design. The maximum tannase production was obtained with a high tannic acid concentration (50 g/l), relatively low incubation temperature ($30^{\circ}C$), and unique low initial pH (4.0). The statistical strategy aided in increasing the enzyme activity nearly 1.97-fold, from 4,030 to 7,955 U/l. Consequently, these findings can lead to the development of a fermentation system that is able to produce large amounts of tannase in economical, compact, and scalable reactors.

• Journal of Korean Public Health Nursing
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• v.13 no.1
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• pp.25-40
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• 1999

This study was to identify various personal characteristics between those having a helper and those not having a helper for ADL and IADL performance in noninstitutionalized elders. Secondary analysis was done with the data collected in 1994 national survey of aged householders. Of the elders with ADL limitations $47.8\%$ had no helper. while $26.2\%$ of those with IADL limitations had no helper. Those elders with a helper experienced more limitations in ADL and in IADL than those with no helper. Most of the helpers were family members. whereas very few had a formal helper. Age period and subjective economic status were significantly different between the groups with a helper and with no helper for both ADL and IADL. Compared to the elders with a helper. those elders with no helper had fewer children living together. whereas they had more grandchildren. They also had more contacts with friends or neighbors. Health status. in general. was worse in those elders with a helper than those with no helper. Logistic regression analysis revealed that ADL and IADL limitations had largest influence on having an ADL helper. The odds ratios for low levels of subjective economic status were very high. As for having an IADL helper. IADL score was the most important predictor. In particular. ADL limitations had a negative effect on having an IADL helper. This finding may indicate the urgency of ADL needs. which leads to the lack of an IADL helper when both ADL and IADL limitations are present. Considering the nature of ADL. those disabled elders with low economic status need public support for their daily activities and for home visiting nursing services. There should be studies of examining the adequacy of help in satisfying basic needs for performing ADL and IADL in elders.

• Journal of Korean Public Health Nursing
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• v.20 no.2
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• pp.119-129
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• 2006

Purpose: This study was conducted to investigate the status of depression and the cognitive function among the elderly over 65 years of age who use the welfare facilities for the aged in the community. Methods: For this study the data were collected from March 27, 2006 to April 14, 2006. Subjects were 92 elderly over 65 years old. The level of depression was estimated with the Beck Depression Inventory, and the cognitive function with the modified Mental Status Questionnaire (MSQ). The Data were analyzed using frequencies, t-test, and Pearson's correlation coefficient with the SPSS/PC program. Results: The results of this study are summarized as follows. 1. The mean score was 13.09 for depression and 8.27 for cognitive function. 2. Analysis according to the demographic characteristics confirmed a statistically significant difference on the level of cognitive function between the elderly who live alone and those who live together(f=4.293, p<0.01) 3. The percentage of the severely and mildly impaired in cognitive function was 7.6% and 6.5%, respectively. 4. The variables of age(f=11.17, p<0.01), educational level(f=15.23, p<0.01), martial status(f=4.084, p<0.01), and economic activity(t=4.41, p<0.01) showed a significant effect on cognitive function. 5. There was no relationship between depression and cognitive function. Conclusion: Social support and a variety of programs at welfare facilities in the community were recommended in order to reduce depression and cognitive impairment in the elderly.

• The Journal of the Korea Contents Association
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• v.15 no.2
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• pp.455-465
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• 2015

This study aims to provide basic data for hospital organizational management by analyzing perception of organizational culture of general hospital employees and its effect on organizational trust activities. A total of 437 employees from the 5 general hospitals in G city were surveyed with anonymous self-administered questionnaires and the result was analyzed by t-test, analysis of variance, Pearson correlation analysis, and multiple regression analysis. As a result, there were differences in the perception of organizational trust culture depending on sex, age, education, and income. The perception of organizational trust culture had a significantly positive correlation with organizational trust activities. The factors such as consideration, social responsibility, morality, and competence had a significantly positive effect on organizational trust activities. This study would help to improve the organizational trust that is perceived by hospital employees by improving organizational trust culture with policy and institutional support.

• Perspectives in Nursing Science
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• v.6 no.1
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• pp.21-37
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• 2009

The purpose of this GWP project was two-fold:(1) to launch an organizational culture improvement for great workplace (2) to improve the perception of nursing personnel on communication and team work in a surgical nursing department of a teaching hospital in Seoul. Using one group pretest-posttest design, nursing personnel's perception on organizational culture related to communication and team work was evaluated. A 10-item, 5-point scale (1.5) survey was administered to 209 nursing personnel in January 2009 and again to 191 nursing personnel in October 2009. From January 2009, AMANNA team has taken activities focused on trust, pride, and fun. AMANNA is an abbreviation of Korean language, which means wonderful meeting and sharing in English. Monthly activities are as follows: choral concerts by nurse managers, welcome and farewell events, praising members for their services, explaining current circumstances, etc. Special activities are as follows: a New Year's greeting party, a spring picnic, beauty classes, a lecture on drug administration, cultural lectures using videos, and presentations of academic posters and another activity. The reliability of measurement was Cronbach's ${\alpha}$: 0.917(pretest), 0.954(posttest). Most nursing personnel's perception on organizational culture was improved (pretest mean=3.50 and posttest mean=3.78, p<.001). "A sense of belonging" showed the greatest improvement among the 10 items(3.18 vs. 3.56, p<.001). "Trust each other" showed the highest score (mean=3.98) in posttest. Frequency of participation and satisfaction showed a significant relationship(r=0.179, p=.021). We believe that this project has made a contribution towards a positive organizational culture. The keys to this initiative's preliminary success have been the leadership support and flexibility in implementing the interventions tailored to the hospital.

• Journal of the Ergonomics Society of Korea
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• v.30 no.5
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• pp.613-619
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• 2011

Objective: The purpose of this study is to compare the muscle activities of lumbar and lower extremity muscles between left and right sides using EMG(Electromyogram) when patients are transferred by physical therapists. Background: Asymmetrical lift was recognized as a major cause of musculoskeletal disorder. Several studies show that physical therapists' transferring patients needs caution as it could cause a lumbar pain to patients but there is not sufficient data to support. Method: Forty healthy rehabilitation hospital physical therapists joined for this study. The subjects were transferred from wheelchair to treatment mat(from left to right) by connecting the EMG device to the patients' body both on erector spine and rectus fermoris. At the moment when subjects were being transferred, the EMG device collected data from both erector spine and rectus femoris and it was normalized as %MVC. Then the EMG data was statistically analyzed using paired t-tests. Results: The EMG data show that the left erector spinae and rectus femoris are more activated than right erector spinae and rectus femoris in all position(p<.05) in a significant degree. Conclusion: The result implies that physical therapists' asymmetrical lifting when patients are transferred by them has a potential cause of musculoskeletal disorder of patients. Further studies will be conducted to find out a same tendency in other muscles of a body and to see if there are other factors to affect to patients during asymmetrical lifting. Application: These results can be used to provide baseline information for more understanding to asymmetrical lift loading.

• The Journal of Korean Association of Computer Education
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• v.15 no.2
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• pp.57-66
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• 2012

It is the advantage of robot programming to improve the learners' interest. However, the drawback is existed in the fact that it is not easy to determine whether the problem lies in the hardware factor or programmed logic when an error takes place. This study is an attempt to develop a simulation tool which assists learners to concentrate on the problems not relating to robot assembling but to robot program. It aims to enable beginners make a sketch of their ideas and examine their logic through simulation. Therefore, an Etoys-based robot programming tool is developed to allows user to download and execute the simulated program into an assembled robot. The significance of this study is that easy activity of sketch-based simulation can support learners to understand how the principles of computer science are applied in daily life such as an automatic door system.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.3
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• pp.230-236
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• 2016

The study was carried out to evaluate the quality of commercial pork and beef jerky at a market in Korea. The amount of food additives, place of origin, meat content, microbiological and physicochemical characteristics were investigated in 46 different jerky samples. Meat contents of pork and beef jerky were 75.2~94.0% and 80.0~95.6%, respectively. Food additives, including sodium nitrite, potassium sorbate, and sodium erythorbate were mainly used in jerky. Pork jerky was processed from domestic pork, and beef jerky was mostly processed from imported beef from the USA, Australia, or New Zealand. Pork jerky contained $23.82{\pm}5.74%$ moisture, $37.86{\pm}7.05%$ crude protein, $6.16{\pm}4.91%$ crude fat, and $4.6.87{\pm}1.76%$ crude ash. Beef jerky contained $26.64{\pm}5.21%$ moisture, $41.36{\pm}3.50%$ crude protein, $4.67{\pm}3.46%$ crude fat, and $7.21{\pm}1.91%$ crude ash. Water activity (Aw) of pork jerky was $0.73{\pm}0.09$ while that of beef jerky was $0.78{\pm}0.08$. Volatile basic nitrogen (VBN) content to jerky was 7.1~36.0 mg/100 g. There was no significant difference in the physicochemical composition of meat type (p<0.05). Coliform, Escherichia coli and Staphylococcus aureus were not detected in pork or beef jerky, whereas yeast and molds were detected below $1.2{\times}10^1CFU/g$ in beef jerky samples.