• The Journal of Advanced Prosthodontics
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• v.10 no.3
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• pp.197-204
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• 2018

PURPOSE. To determine the extent of treatment traces, the roughness depth, and the quantity of titanium nitride (TiN) removed from the surface of CAD/CAM abutments after treatment with various instruments. MATERIALS AND METHODS. Twelve TiN coated CAD/CAM abutments were investigated for an in vitro study. In the test group (9), each abutment surface was subjected twice (150 g vs. 200 g pressure) to standardized treatment in a simulated prophylaxis measure with the following instruments: acrylic scaler, titanium curette, and ultrasonic scaler with steel tip. Three abutments were used as control group. Average surface roughness (Sa) and developed interfacial area ratio (Sdr) of treated and untreated surfaces were measured with a profilometer. The extent of treatment traces were analyzed by scanning electron microscopy. RESULTS. Manipulation with ultrasonic scalers resulted in a significant increase of average surface roughness (Sa, P<.05) and developed interfacial area ratio (Sdr, P<.018). Variable contact pressure did not yield any statistically significant difference on Sa-values for all instruments (P=.8). Ultrasonic treatment resulted in pronounced surface traces and partially detachment of the TiN coating. While titanium curettes caused predominantly moderate treatment traces, no traces or detectable substance removal has been determined after manipulation with acrylic curettes. CONCLUSION. Inappropriate instruments during regular plaque control may have an adverse effect on the integrity of the TiN coating of CAD/CAM abutments. To prevent defects and an increased surface roughness at the transmucosal zone of TiN abutments, only acrylic scaling instruments can be recommended for regular maintenance care.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.582-588
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• 2013

The impact of global warming on aquatic systems has been a priority research area in the past decade. However, the possibility that increased temperatures will cause shifts in viral disease outbreaks has not been well addressed. In the present study, with increasing water temperature (WT) in the coastal area of Korea, we estimated the possibility of changes in fish viral diseases. From the present time, WT may rise between 0.62 and $1.7^{\circ}C$ by 2050, and the effect on aquaculture could be more adverse than benefitial. Red seabream iridovirus disease (RSIVD) and viral nervous necrosis (VNN) cause high mortality above 22 and $24^{\circ}C$, respectively, and outbreaks could commence earlier and persist for prolonged periods. Nevertheless, the period of occurrence of viral hemorrhagic septicemia (VHS), which outbreaks at a lower WT (< $18^{\circ}C$), could be shorter than the current infectious period. Thermal stress in fish causes reductions in growth and immunocompetence; thus, increases in summer WT can lead to the development of new viral diseases. WT has a strong influence on fish population dynamics; therefore, entry of new viruses and changes in the prevalence of infection can be expected if carrier fishes are introduced or migrate to Korean waters.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.67-74
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• 2009

Exposures to environmental chemicals that mimic endogenous hormones are proposed for a number of adverse health effects, including infertility, abnormal prenatal and childhood development and above all cancers. In addition, recently miRNA (micro RNA) has been recognized to play an important role in various diseases and in cellular and molecular responses to toxicants. In this study, endocrine disrupting environmental toxicant, nonylphenol (NP) was treated to MCF-7 (Human breast cancer cell) and HepG2 (Human hepatocellular liver carcinoma) cell line at 3 hrs and 48 hrs time point and miRNA analysis using $mirVana^{TM}$ miRNA bioarray was performed and compared with total mRNA microarray data for the same cell line and treatment. Robust data quality was achieved through the use of dye-swap. Analysis of microarray data identifies a total of 20 and 11 miRNA expressions at 3 hrs and 48 hrs exposure to NP in MCF-7 cell line and a total of 14 and 47 miRNA expression at 3 hrs and 48 hrs exposure respectively to NP in HepG2 cell line. Expression profiling of the selected miRNA (let-7c, miR-16, miR-195, miR-200b, miR200c, miR-205, and miR-589) reveals changes in the expression of target genes related to metabolism, immune response, apoptosis, and cell differentiation. The present study can be informative and helpful to understand the role of miRNA in molecular mechanism of chemical toxicity and their influence on hormone dependent disease. Also this study may prove to be a valuable tool for screening potential estrogen mimicking pollutants in the environment.

• The Journal of Korean Association of Computer Education
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• v.15 no.5
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• pp.23-31
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• 2012

The purpose of this study is to seek solutions for the adverse effects of the informatization by analyzing the influential factors of internet addiction to maximize prevention of the internet addiction for highschool students. The causal factors of the internet addiction are classified into three categories: personal factors, familial factors, and social environmental factors. To validate the study, the questionnaires were given to four high schools which were two generalized high schools and two specialized high schools in the Seoul and Kyunggi Area. The most influential factor of the internet addiction was identified, and hierarchical influence among factors were analyzed by evaluating the questionnaires. The result of the generalized high schools was different from that of the specialized high schools. It proved that different countermeasures must be prepared depending on environment of internet users. Therefore, diverse and comprehensive solutions for internet addiction must be devised to solve the problem of internet addiction.

• The Journal of Internal Korean Medicine
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• v.40 no.6
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• pp.1202-1209
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• 2019

Objectives: The purpose of this study was to confirm the effects of an auricular acupressure (AA) program for smoking cessation in high school students from 2015 to 2017. Methods: The study investigated 12 high school students who had been smokers. Subjects were treated for three years. Each program was composed of five AA treatments. Average daily smoking and adverse reactions were checked for one week before each procedure. The AA was administered weekly at the endocrine point, lung point, throat point, nasal fossae point, bronchial tube point, and mouth point. Results: The mean number of cigarettes smoked per day after each year of treatment significantly decreased from 5.33±3.58 to 3.54±2.08 in 2015 (p=0.046). However, it increased from 5.75±2.30 to 6.00±3.61 in 2017 (p=0.80). The number of cigarettes smoked before treatment was found to be higher than the number of cigarettes after treatment in the previous year. No significant results were obtained from analysis of the change in the amount of smoking within each year. Conclusion: Social influence, such as the subject's academic stress and peer relationships, may have been a major factor in the change in the amount of smoking. Although the AA did not show a strong effect in smoking cessation, it appears to have value as a supplementary means of stopping smoking.

• The Korean Journal of Food And Nutrition
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• v.23 no.1
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• pp.70-75
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• 2010

This study was conducted to determine the influence of culture conditions such as temperature, time, water content, koji-thickness and agitation on the production of organic acid by Rhizopus sp. ZB9 isolated from Korean Nuruk during the preparation of rice koji, which is used in brewing the Korean rice wines, Takju and Yakju. Rice koji was made under different culture conditions, and the acidity of each koji was tested. The temperature range suitable for the production of organic acid was $28{\sim}32^{\circ}C$, and 36~48 hours of cultivation at that temperature range seemed to produce the optimum results. The production of organic acid increased in proportion to the increase in water content of steamed rice from 25% to 60%. An increase in koji-thickness induced no adverse effects on the production of organic acid, and agitation-work during cultivation showed very beneficial effects.

• Journal of Environmental Health Sciences
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• v.43 no.2
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• pp.122-129
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• 2017

Objectives: Most of the $PM_{10}$ in subway stations is spread by the train-induced wind from the tunnels. Therefore, in order to improve air quality in subway stations, it is important to remove the $PM_{10}$ from the tunnels. After the installation of PSD (platform screen doors), the influence of train-induced wind and $PM_{10}$ at the platform has decreased, but is estimated to have increased in subway tunnels. This study was conducted to investigate the control of $PM_{10}$ in subway tunnels by applying a 500-fold diluted solution mixed with a humectant using a natural polymer. Methods: For this purpose, we tested the dust reduction effect in a laboratory and corrosion test and water pollution using fish and aquatic plants for the natural dust collecting agent. In the tunnel of a subway station, we used the natural dust collecting agent over 15 days. The study was carried out on $PM_{10}$ control during operation, which accounts for more than 70% of subway dust. Results: As results, the natural dust collecting agent exhibited an excellent dust control effect, and it was safe for water quality and soil. It showed the effect of controlling $PM_{10}$ in the subway tunnel by 49.5- 64.7% over 15 days. The use of the dust collecting agent for the control of $PM_{10}$ could be confirmed in the subway. Conclusion: It is necessary to clearly explain the major portions of chemical components contained in $PM_{10}$ to figure out the characteristics of $PM_{10}$ and to develop effective reduction measures to decrease the adverse effects of $PM_{10}$ in the subway.

• Journal of Gastric Cancer
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• v.16 no.4
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• pp.260-265
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• 2016

Purpose: The aim of this study was to evaluate tolerance to adjuvant chemotherapy, and to compare survival between treatments using only surgery and using surgery with adjuvant chemotherapy, in elderly patients with advanced gastric cancer who were ${\geq}75years$ of age. Materials and Methods: Patients ${\geq}75years$ of age who were diagnosed with pathological stage II or III gastric cancer were identified retrospectively and categorized into the surgery only and surgery with adjuvant chemotherapy groups. Clinicopathological and survival data were compared between these two groups. Results: Among the 130 patients studied, 67 patients underwent curative surgery only, and 63 patients received adjuvant chemotherapy after curative surgery. In the latter group, adverse events were reported in 24 patients (38.1%). The treatments were discontinued in 19 patients (30.2%) owing to any reason. The overall 5-year survival rates of the surgery only and the surgery with adjuvant chemotherapy groups did not differ significantly (44.1% vs. 30.7%, respectively; P=0.804). Among 90 death events, deaths from recurrences of gastric cancer occurred in 42 patients. Multivariate analyses revealed that the American Society of Anesthesiologists score and the depths of tumor invasions were related to survival, and the addition of adjuvant chemotherapy after surgery did not influence survival. Conclusions: The decision for the addition of adjuvant chemotherapy for elderly patients should be taken after considering the condition of individual patients and their life expectancies.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.821-827
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• 2002

The purpose of this study was to evaluate the effect of protected fat and heat-extruded soybean meal on the lactation performance of Holstein cows. Twenty-four cows, consisting of 20 lactating cows and 4 rumen-fistulated dry cows, were randomly allocated into four groups with 5 lactating cows and 1 fistulated cow in each group. A replicated 4${\times}$4 Latin square design with four 21 day periods, including 14 days of adaptation and 7 collection days within each period was employed. The experiment was a 2${\times}$2 arrangement, with or without heat-extruded soybean meal and protected fat inclusion. The dietary treatments consisted of supplements of (a) soybean meal (the control), (b) heat-extruded soybean meal, (c) protected fat, and (d) heat-extruded soybean meal and protected fat. The results showed that there were no significant differences in feed intake, milk yield, milk protein content, milk lactose content and body weight change between the dietary treatments. However, cows supplemented with protected fat showed a significantly increased (p<0.05) milk fat yield, 3.5% FCM and total solid yield. The increase in undegradable intake protein (UIP) via heat extruded soybean meal supplement significantly decreased the urea nitrogen concentration in the blood (p<0.05). Dietary fat inclusion significantly increased the blood cholesterol concentration (p<0.01) and decreased the ruminal pH value (p<0.01). Increased dietary UIP significantly decreased the ammonia nitrogen concentration in the rumen (p<0.01), but did not significantly influence the pH and VFA molar percentage in the rumen. It appears that dietary protected fat inclusion could improve milk fat and solid content. Increased dietary undegradable intake protein through heat extruded soybean meal did not improve milk yield. But it could alleviate the adverse effect of decreased milk protein due to dietary fat supplementation. Increased UIP could also decrease the ammonia nitrogen concentration in the rumen and plasma urea nitrogen concentration in the blood.

• Korean Journal of Biological Psychiatry
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• v.8 no.2
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• pp.208-219
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• 2001

The pharmacotherapy of schizophrenia exhibits wide inter-individual variabilities in clinical efficacy and adverse effects. Recently, human genetic diversity has been known as one of the essential factors to the variation in human drug response. This suggests that drug therapy should be tailored to the genetic characteristics of the individual. Pharmacogenetics is the field of investigation that attempts to elucidate genetic basis of an individual's responses to pharmacotherapy, considering drug effects divided into two categories as pharmacokinetics and pharmacodynamics. The emerging field of pharmacogenomics, which focuses on genetic determinants of drug response at the level of the entire human genome, is important for development and prescription of safer and more effective individually tailored drugs and will aid in understanding how genetics influence drug response. In schizophrenia, pharmacogenetic studies have shown the role of genetic variants of the cytochrome P450 enzymes such as CYP2D6, CYP2C19, and CYP2A1 in the metabolism of antipsychotic drugs. At the level of drug targets, variants of the dopamine $D_2$, $D_3$ and $D_4$, and 5-$HT_{2A}$ and 5-$HT_{2C}$ receptors have been examined. The pharmacogenetic studies in schizophrenia presently shows controversial findings which may be related to the multiple involvement of genes with relatively small effects and to the lack of standardized phenotypes. For further development in the pharmacogenomics of schizophrenia, there would be required the extensive outcome measures and definitions, and the powerful new tools of genomics, proteomics and so on.