• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.523-532
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• 2004

The present study was carried out to investigate the potential adverse effects of amitraz on pregnant dams after maternal exposure during the gestational days (GD) 1 through 19 in Sprague-Dawley rats. The test chemical was administered orally to pregnant rats at dose levels of 0, 3, 10, or 30 mg/kg/ day. During the test period, clinical signs, mortality, body weights, food consumption, serum biochemistry, gross findings, organ weights and reproductive findings on GD 20 were examined. In the 30 mg/kg group, an increase in the incidence of abnormal clinical signs and death, a suppression in the body weight gain, and a decrease in the food consumption were observed. A decrease in the liver weight and increases in the kidneys, adrenal glands and heart weights were also found. Serum biochemical investigations revealed increases in the aspartate aminotransferase (AST), total bilirubin, and chloride. In addition, an increase in the fetal death and decreases in the litter size and fetal body weight were seen at caesarean section. Inthe 10 mg/kg group, an increase in the incidence of abnormal clinical signs, decreases in the food consumption and liver weight, increases in the total bilirubin and chloride, and a decrease in the fetal body weight were observed. There were no adverse effects on clinical signs, mortality, body weights, food consumption, serum biochemistry, gross findings, organ weights and reproductive findings in the 3 mg/kg group. Based on the results, it was concluded that the 19-day repeated oral dose of amitraz to pregnant rats caused increases in the clinical signs, kidneys, adrenal glands and heart weights, AST, total bilirubin and chloride and decreases in the body weight gain, food consumption and liver weight at the dose levels of above 10 mg/kg/day. Under the present experimental conditions, the no-observed-adverse-effect level (NOAEL) of amitraz was considered to be 3 mg/kg/day.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.530-545
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• 1996

The purpose of this study was to investigate by spectrophotometry the changes in color parameters of composite resins after exposure to distilled water, filtered coffee, and artificial saliva. Five kinds of fine particle composite resin in experiment 1, and six kinds of composite resin in experiment 2 were used. In experiment 1, each group of composite resin was stored in distilled water at $4^{\circ}C$, $50^{\circ}C$, and filtered coffee solution at $4^{\circ}C$, $50^{\circ}C$. And then each specimen was measured by spectrophotometer. Measurements were repeated in 1 hour, 2 hours, 4 hours, 8 hours, 16 hours, 24 hours, and 48 hours. In experiment 2, all specimens of each brand were stored in distilled water at $37^{\circ}C$, artificial saliva not contained mucin at $37^{\circ}C$, and artificial saliva contained mucin at $37^{\circ}C$. All specimens of each brand were measured by spectrophotormeter in 1 week, 2 weeks, 4 weeks, 8 weeks, and up to 12 weeks. The results were as follows : 1. In cold coffee, five of fine particle composite resins showed ${\Delta}E{^*}_{ab}$ values less than 2. However, in hot coffee ${\Delta}E{^*}_{ab}$ values of Amelogen Universal and Prisma TPH were higher than those of Conquest Crystal, ${\AE}$litefil and Z100. 2. Z100 and ${\AE}$litefil had better cleansibility of extrinsic coffee staining than Amelogen Universal, Conquest Crystal and Prisma TPH. 3. In distilled water and artificial saliva not contained mucin, five of fine particle composite resin showed ${\Delta}E{^*}_{ab}$ values less than 2 up to 12 weeks. However, Silux Plus showed higher than ${\Delta}E{^*}_{ab}$ values of fine particle composite resin. 4. As an immersion solution for discoloration experiment, artificial saliva not contained mucin showed similar appearance as distilled water. However, artificial saliva contained mucin had different appearance from the others. 5. In artificial saliva contained mucin, ${\AE}$litefil, Prisma TPH and Z100 showed ${\Delta}E{^*}_{ab}$ values less than 1 up to 12 weeks. However, Silux Plus, Amelogen Universal and Conquest Crystal showed ${\Delta}E{^*}_{ab}$ values more than 1 up to 12 weeks. But, Conquest Crystal showed different characteristics of chromacity difference value(less chromatic) and lightness difference value(lighter) from Silux Plus and Amelogen Universal.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.397-403
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• 2018

The leaves of Spiraea prunifolia were extracted with 80% aqueous MeOH and the concentrates were partitioned into EtOAc, n-BuOH, and $H_2O$ fractions. The repeated $SiO_2$ or ODS column, and medium pressure liquid chromatographies for the n-BuOH fraction led to isolation of two phenolic glucosides. The chemical structures of these compounds were determined as isosalicin (1) and crenatin (2) based on spectroscopic analyses including Nuclear magnetic resonance and MS. Extracts were analyzed using UPLC-MS/MS providing a short analysis time within 5 min using MRM technique. The concentration of crenatin was higher as 9.53 mg/g and isosalicin was lower as 0.65 mg/g. Neuroprotective effects of these compounds against hydrogen peroxide ($H_2O_2$)-induced neurotoxicity were evaluated. The results showed that exposure to $H_2O_2$ induced morphological changes, cell death and neurotoxicity in SK-N-MC cells. However, pretreatment with crenatin resulted in inhibition of morphological change, reduction of loss of cell viability and attenuation of neuronal damage. These results suggested that neuroprotective effect of crenatin isolated from S. prunifolia can be a good candidate for the development of health beneficial foods which can ameliorate the degenerative neuronal disease caused by oxidative stress.

• Toxicological Research
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• v.35 no.4
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• pp.361-369
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• 2019

1,2-Dichloropropane (1,2-DCP) has been used as an industrial solvent and a chemical intermediate, as well as in soil fumigants. Human exposure may occur during its production and industrial use. The target organs of 1,2-DCP are the eyes, respiratory system, liver, kidneys, central nervous system, and skin. Repeated or prolonged contact may cause skin sensitization. In this study, 1,2-DCP was dissolved in corn oil at 0, 2.73, 5.75, and 8.75 mL/kg. The skin of mice treated with 1,2-DCP was investigated using western blotting, hematoxylin and eosin staining, and immunohistochemistry. 1,2-DCP was applied to the dorsal skin and both ears of C57BL/6J mice. The thickness of ears and the epidermis increased significantly following treatment, and the appearance of blood vessels was observed in the dorsal skin. Additionally, the expression of vascular endothelial growth factor, which is tightly associated with neovascularization, increased significantly. The levels of protein kinase-B (PKB), phosphorylated PKB, mammalian target of rapamycin (mTOR), and phosphorylated mTOR, all of which are key components of the phosphoinositide 3-kinase/PKB/mTOR signaling pathway, were also enhanced. Taken together, 1,2-DCP induced angiogenesis in dermatitis through the PI3K/PKB/mTOR pathway in the skin.

• Korean Journal of Cognitive Science
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• v.33 no.2
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• pp.95-107
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• 2022

Facial processing of different racial origin has been investigated at various levels including perceptual, emotional, and socio-cultural processing. Particularly, a good deal of studies have been conducted to show "other race effect (ORE)" to indicate that subtle facial information such as identity or emotional expressions are often under-processed in racial out-group members. However, few studies have investigated whether attentional modulation toward racial out-group faces could explain ORE. We investigated whether novelty-driven attentional mechanism is involved in face perception using event-related potential (ERP). Twenty-two Korean (KR) and nine Caucasian-American (AM) participants were presented with emotional faces from the two racial origins while they performed a gender categorization task. KRs showed significantly greater P3 amplitudes to AM than to KR faces indicating that the early attentional processing underlies differential perception of racial out-group faces. Interestingly, P3 was not up-regulated in the AM subjects when they were presented with KR faces, perhaps due to massive habituation to KR faces during everyday social interaction. These results indicate that racial out-group faces are highly salient stimuli which automatically occupy attentional resources, but easily habituated with repeated exposure to the racial-out group.

• Journal of Pharmacopuncture
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• v.27 no.1
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• pp.27-37
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• 2024

Objectives: Posttraumatic stress disorder (PTSD) is a prevalent mental health condition, and techniques using sensory stimulation in processing traumatic memories have gained attention. The Emotional Freedom Techniques (EFT) is a psychotherapy that combines tapping on acupoints with exposure to cognitive reframing. This pilot study aimed to assess the feasibility of EFT as a treatment for PTSD by answering the following research questions: 1) What is the compliance and completion rate of patients with PTSD with regard to EFT protocol? Is the dropout rate reasonable? 2) Is the effect size of EFT protocol for PTSD sufficient to justify a future trial? Methods: Thirty participants diagnosed with PTSD were recruited. They received weekly EFT sessions for five weeks, in which they repeated a statement acknowledging the problem and accepting themselves while tapping the SI3 acupoint on the side of their hand. PTSD symptoms were evaluated using the PTSD Checklist for DSM-5 (PCL-5) before and after the intervention. Results: Of the 30 PTSD patients (mean age: 34.1 ± 9.1, 80% female), 96.7% showed over 80% compliance to the EFT sessions, and 86.7% completed the entire study process. The mean PCL-5 total score decreased significantly after the intervention, with a large effect size (change from baseline: -14.33 [95% CI: -19.79, -8.86], p < 0.0001, d = 1.06). Conclusion: The study suggests that EFT is a feasible treatment for PTSD, with high session compliance and low dropout rates. The effect size observed in this study supports the need for a larger trial in the future to further investigate EFT as a treatment for PTSD. However, the lack of a control group and the use of a self-rated questionnaire for PTSD symptoms are limitations of this study. The findings of this pilot study can be used to plan a future trial.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.3
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• pp.21-25
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• 1979

To evaluate the possibility of hardening of rice seedlings to chilling injury by low temperature conditioning for improvement of nursery temperature management a chilling sensitive new variety Tongil from Indica \times Japonica cross and a chilling tolerant Japonica variety Jinheung were reared by the 3rd leaf-stage in a day $30^{\circ}C/night\; 20^{\circ}C$ growth chamber, and were subjected to temperature conditioning for hardening against chilling injury for 6 days. Then the seedlings conditioned and unconditioned were chilled in a day and night $8^{\circ}C$ chamber for 2, 4, 6, or 8 days long and returned to the day and night $30^{\circ}C/night\; 20^{\circ}C$ condition for development of chilling injuries. Survival rate after chilling injury development of the variety Tongil showed distinct effect of hardening, i. e. the unhardened-25 % survival, the hardened by a gradual drop of temperature regime $(30^{\circ}C/20^{\circ}C\rightarrow24^{\circ}C/14^{\circ}C\rightarrow18^{\circ}C/12^{\circ}C\rightarrow8^{\circ}C)4 -59% survival and the hardened. by repeated brief exposure (4hrs. to 6hrs.) to $8^{\circ}C$ shock-89% survival against chilling of $8^{\circ}C$ for 4 days long. The variety Jinheung survived even against 8 days chilling at $8^{\circ}C$ C, but the discoloration rate of leaves due to chilling showed noticeably the hardening effect as repeated shock was much better than the gradually lowering temperatures.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.227-233
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• 2004

Chronic exposure to solar radiation, particularly ultraviolet (UV) light, causes a variety of adverse reactions on human skin, such as sunburn, photoaging and photocarcinogenesis. Free radicals and reactive oxygen species (ROS) caused by UV exposure or other environmental facts play critical roles in cellular damage. And, repeated-UV irradiation activated the expression of the matrix metalloproteinase (MMP) and induced skin irritation. Therefore, the development of effective and safe photoprotectants that can reduce and improve the skin damage has been required. The purpose of this study was to investigate the photo-protective effect of several chinese medical plants (Juniperus chinensis) on the UV -induced skin cell damages. We tested free radical and superoxide scavenging effect in vitro. Fluorometric assays of the proteolytic activities of MMP-1 (collagenase) were performed using fluorescent collagen substrates. UVA induced MMP-1 synthesis and activity were analyzed by enzyme-linked immunosorbent assay (ELISA) and gelatin-based zymography in skin fibroblasts. We also examined anti-inflammatory effects by the determination test of proinflammatory cytokine, interleukin 6 in HaCaT keratinocytes. Expression of prostaglandin E$_2$ (PGE$_2$) after UVB irradiation was measured by competitive enzyme immunoassay(EIA) using PGE$_2$ monoclonal antibody. In the human skin we tested anti-irritation effect on the SLS-induced damage skin after appling the extract containing emulsion. We found that Juniperus chinensis extract had potent radical scavenging effect by 98% at 100$\mu\textrm{g}$/mL. The extract of Juniperus chinensis showed strong inhibitory effect on MMP-1 activities by 97% at 100 $\mu\textrm{g}$/mL and suppressed the UVA induced expression of MMP-1 by 79% at 25$\mu\textrm{g}$/mL. This extract also showed strong inhibition on MMP-2 activity in UVA irradiated fibroblast by zymography. In the test of proinflammatory cytokines of human keratinocytes Juniperus chinensis extract decreased expression of interleukin 6 about 30%. The amount of PGE$_2$ by HaCaT keratinocytes was significantly increased at the doses of above 10 mJ/$\textrm{cm}^2$ of UVB (p < 0.05). At the concentrations of 3.2-25$\mu\textrm{g}$/mL of this extract, the production of PGE$_2$ by HaCaT keratinocytes (24 h after 10mJ/$\textrm{cm}^2$ UVB irradiation) was significantly inhibited in culture supernatants (p < 0.05). In SLS-induced skin irritation model in vivo, we found to reduce skin erythema and improve barrier recovery after appling Juniperus chinensis extract containing emulsion when compared to irritated non-treated and placebo-treated skin. Our results suggest that Juniperus chinensis extract can be effectively used for the prevention of UV and SLS-induced adverse skin reactions and applied as anti-aging and anti-irritation cosmetics.

• Tuberculosis and Respiratory Diseases
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• v.40 no.3
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• pp.236-249
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• 1993

Background: Among the injurious agents to which the lung airspaces are constantly exposed are reactive species of oxygen. It has been widely believed that reactive oxygen species may be implicated in the etiology of lung injuries. In order to elucidated how this oxidant causes lung cell injury, we investigated the effects of exogenous $H_2O_2$ on alveolar epithelial barrier characteristics. Methods: Rat type II alveolar epithelial cells were plated onto tissue culture-treated polycarbonate membrane filters. The resulting confluent monolayers on days 3 and 4 were mounted in a modified Ussing chamber and bathed on both sides with HEPES-buffered Ringer solution. The changes in short-circuit current (Isc) and monolayer resistance (R) in response to the exogenous hydroperoxide were measured. To determine the degree of cellular catalase participation in protection against $H_2O_2$ injury to the barrier, experiments were repeated in the presence of 20 mM aminotriazole (ATAZ, an inhibitor of catalase) in the same bathing fluid as the hydroperoxide. Results: These monolayers have a high transepithelial resistance (>2000 ohm-$cm^2$) and actively transport $Na^+$ from apical fluid. $H_2O_2$(0-100 mM) was then delivered to either apical or basolateral fluid. Resulting indicated that $H_2O_2$ decreased Isc and R gradually in dose-dependent manner. The effective concentration of apical $H_2O_2$ at which Isc (or R) was decreased by 50% at one hour ($ED_{50}$) was about 4 mM. However, basolateral $H_2O_2$ exposure led to $ED_{50}$ for Isc (and R) of about 0.04 mM. Inhibition of cellular catalase yielded $ED_{50}$ for Isc (and R) of about 0.4 mM when $H_2O_2$ was given apically, while $ED_{50}$ for basolateral exposure to $H_2O_2$ did not change in the presence of ATAZ. The rate of $H_2O_2$ consumption in apical and basolateral bathing fluids was the same, while cellualr catalase activity rose gradually with time in culture. Conclusion: Our data suggest that basolateral $H_2O_2$ may affect directly membrane component (e.g., $Na^+,\;K^+$-ATPase) located on the basolateral cell surface. Apical $H_2O_2$, on the other hand, may be largely degraded by catalase as it passes through the cells before reaching these membrane components. We conclude that alveolar epithelial barrier integrity as measured by Isc and R are compromised by $H_2O_2$ being relatively sensitive to basolateral (and insensitive to apical) $H_2O_2$.

• Progress in Medical Physics
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• v.11 no.1
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• pp.59-71
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• 2000

It is possible to obtain a fast CT scan during breath holding with spiral technique. But the risk of radiation is increased due to detailed and repeated scans. However, the limitation of X-ray doses is not fully specified on CT, yet. Therefore, the purpose of the present study is to define the limitation of X-ray doses on CT The CT unit was somatom plus 4. Alderson Rando phantom, Solenoid water phantom, TLD, and reader were used. For determining adequate position and size of organs, the measurement of distance(${\pm}$2mm) from the midline of vertebral body was performed in 40 women(20~40 years). On the brain scan for 8:8(8mm slice thickness, 8mm/sec movement velocity of the table) and 10:10(10mm slice thickness, 10mm/sec movement velocity of the table) methods, the absorption doses of exposed area of the 10:10 were slightly higher than those of 8:8. The doses of unexposed uterus were negligible on the brain scan for both 8:8 and 10:10. On the chest scan for 8:8, 8:10(8mm slice thickness, 10mm/sec movement velocity of the table), 10:10, 10:12(10mm slice thickness, 12mm/sec movement velocity of the table) and 10:15(10mm slice thickness, 15mm/sec movement velocity of the table) methods, 8:8 method of the absorption doses of exposure area was the most highest and 10:15 method was the most lowest. The absorption doses of 8:10 method was relatively lower than those of the other methods. In conclusion, the 8:10 method is the most suitable to give a low radiation burden to patient without distorting image quality.