• Korean Journal of Ecology and Environment
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• v.55 no.2
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• pp.120-131
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• 2022

Microcystins (MCs) are cyano-toxins mainly produced by cyanobacteria in the genera of Microcystis, Anabaena, and Oscillatoria. The concentrations of MCs in the water bodies and fish tissues taken from the four weirs (Ipo, Gangjeong-goryeong, Baekje, and Juksan) in the four main rivers in Korea, and the health risk of human due to consumption of toxin-detected fish was examined. The maximum values of MCs concentration in the water samples were as follows: Juksan (3.261 ㎍ L^-1), Gangjeong-goryeong (1.014 ㎍ L^-1), Baekje (0.759 ㎍ L^-1), and Ipo (0.266 ㎍ L^-1) weirs. The MC-RR concentration was the highest among the MCs, and MC-YR was not detected. MCs of 0.222~9.808 ㎍ g^-1 dry weight were detected in the liver of 3 out of 215 fishes of 16 species, and below the detection limit in muscle. As a result of comparing the feeding characteristics of the collected fishes and toxin concentrations in water and fish tissue, it was concluded that the biomagnification of MCs through the food chain did not occur. It was judged that there was no health risk due to the consumption of the fish detected the toxin, based on the amount of the fish intake of the Korean people and the allowable daily intake of MCs. However, in order to reduce the health risk due to MCs, further studies should be conducted to analyze the concentration of MCs contained in fish tissues collected at various times in the area dominated by harmful cyanobacteria to obtain data on the exposure of MCs due to fish consumption. In addition, it is necessary to establish the management guidelines for MCs in fish tissues.

• Development and Reproduction
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• v.12 no.3
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• pp.251-259
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• 2008

The plasticizer di(2-ethylhexyl)phthalate(DEHP) is one of the most well known endocrine disrupting chemicals (EDCs) because of its strong anti-androgenic effects on the reproductive and developmental process in male rodents and human. The present study was performed to examine whether prepubertal exposure to DEHP can make any alteration during the maturation of accessory sex organs in male rats. As a result, there was no significant change in body weights, serum T levels and tissue weights except of seminal vesicle and ventral prostate in DEHP-treated animals compared to vehicle-treated ones. The seminal vesicle weights in high-dose group (200 mg/kg) were significantly lower than those from the control group (p<0.05), and ventral prostate weights were significantly lower than those from the control group (p<0.05) in both low-dose (20 mg/kg) and high-dose group. Histological studies revealed that the seminal vesicles from DEHP-treated groups showed reduced areas of mucosal folds. Pseudostratified columnar epithelia were observed in the ventral prostates of DEHP-treated samples while cuboidal epithelia were found in the control group. The transcriptional activities of ER-$\alpha$ in seminal vesicle from high-dose group (p<0.05) were significantly higher than those from the control group, and ER-$\beta$ expression was significantly decreased in low-dose group (p<0.05) compared to the control. In ventral prostate, ER-$\beta$ mRNA levels from low-dose group (p<0.05) were significantly lower than those from the control group, and significantly increased in high-dose group (p<0.01). AR expressions, however, were not significantly different in all experimental groups of both seminal vesicle and ventral prostate. In conclusion, the present study demonstrated that (i) adverse effect (s) of DEHP on sexual maturation during prepubertal period could be limited, (ii) seminal vesicle and prostate gland were sensitive targets to DEHP in prepubertal rats and (iii) the deleterious effects of DEHP might be mediated through ER-associated mechanism.

• Journal of Life Science
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• v.33 no.2
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• pp.169-175
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• 2023

As a protective defensive mechanism against ultraviolet (UV) light exposure in skin tissue, melanocytes produce the pigment melanin. Tyrosinase plays a key role in melanin production in melanocytes. However, the overproduction of melanin can lead to lesions, such as freckles and dark spots. Thus, it is clinically important to find a modulating molecule to control melanogenesis by regulating tyrosinase expression and/or activity. It is known that catechin, a plant flavonoid, can reduce melano- genesis through the downregulation of tyrosinase expression. Here, we tested whether catechin derivatives isolated from the stem bark of Ulmus parvifolia have an effect on melanin production by regulating tyrosinase in mouse melanoma cells and in vitro mushroom tyrosinase. The catechin derivatives used in this study included C5A, C7A, C7G, and C7X. Treatments using these catechin derivatives reduced melanin production in mouse melanoma B16F10 cells in which melanogenesis was stimulated by α-MSH. Notably, the anti-melanogenic effects of catechin derivatives were similar to those of kojic acid, a well-known anti-melanogenic molecule. Both C5A and C7A directly inhibited the activity of tyrosinase isolated from mushrooms in vitro. Furthermore, our in silico computational simulation showed that these two compounds were expected to bind to the active site of tyrosinase, which is similar to kojic acid. In addition, all four catechin derivatives reduced tyrosinase protein expression. In summary, our results showed that catechin derivatives can reduce melanogenesis by regulating tyrosinase activity or expression. Thus, this study suggests that catechin derivatives isolated from U. parvifolia can be novel modulators of melanin production.

• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.116-135
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• 2004

This study was conducted to investigate effects of spent composts of Se-enriched mushrooms as the dietary Se source on muscular Se deposition and plasma glutathione peroxidase (GSH-Px) activity in the finishing Hanwoo steer. Twenty Hanwoo steers were used in the experiment and they were divided into four groups in a randomized complete block design with five replicates. Treatments were four levels (0.1, 0.3, 0.6 and 0.9ppm as fed basis) of dietary Se from the combination with spent composts of Se-enriched mushrooms and/or Se non-enriched mushrooms, in which each treatment was formulated with corn and corn gluten meal and so forth. Treatment diets were fed to Hanwoo steers for 90 days until the slaughter. Dry matter intakes had no significant differences among treatments and there were no significant differences for performances such as total BW gain and ADG among treatments. The Se concentration in blood was linearly increased with increasing dietary selenium levels and reached a plateau level after 8 weeks (p<0.001). Plasma GSH-Px activities had the similar trends to blood Se concentrations by showing that the increased dietary Se level significantly increased plasma GSH-Px activities of both total and Se-dependent (p<0.001). Muscle Se contents of Se-supplemented groups were linearly increased by 1.35 ~ 1.68 folds compared with the control group (0.1ppm; 0.273㎍/dry g) and especially those of the hind legs for 0.9ppm treatment showed the highest Se content as shown 0.457㎍ per dry gram (p<0.01) corresponding to approximately 70% increase of the control group. Se retention rate in the muscle of dietary Se originated from spent composts of Se-enriched mushrooms was estimated of maximum approximately 30% and dietary Se content showed the significant correlation with plasma GSH-Px activities and muscle Se contents (p<0.01). Accordingly, Se present in spent composts of Se-enriched mushroom as the dietary Se source not only had great bioavailabilities showing higher blood Se concentration and plasma GSH-Px activities, but also increased Se deposition in the muscle for Hanwoo beef cattle.

• Journal of the Korean Applied Science and Technology
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• v.40 no.2
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• pp.223-232
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• 2023

Oxidative stress plays a significant role in the pathogenesis of various skin conditions, resulting in cellular and tissue damage that can contribute to the development of skin tone unevenness, roughness and wrinkles. In this study, we found that Trifolium pratense L. extract (TE) attenuated oxidative-induced damage in HaCaT cells and elucidated the underlying molecular mechanism. Our finding demonstrated that TE effectively protected HaCaT cells against H₂O₂-induced cell death by inhibiting caspase-3 activation, downregulating Bax and upregulating Bcl-2, and attenuating the activation of three mitogen-activated protein kinases (MAPKs). Our results suggest that TE has remarkable cytoprotective properties against oxidative damage in HaCaT cells and could serve as a complementary or alternative approach to prevent and treat skin damage.

• Journal of the Korean Orthopaedic Association
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• v.54 no.6
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• pp.547-556
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• 2019

Purpose: This study evaluated the results of surgical treatment for residual or recurrent deformity after the conservative treatment of idiopathic clubfoot. Materials and Methods: Fifty-one cases (32 patients), who were followed up to skeletal maturity, were reviewed retrospectively. The mean age at the last follow-up was 18.7 years. The surgical options included selective or comprehensive soft tissue release, tendon lengthening and transfer, and various types of osteotomy. The radiology measurements included the talocalcaneal angle and talo-first metatarsal angle in the anteroposterior (AP) view, and the talocalcaneal angle and calcaneal pitch in the lateral view. The radiology measurements were compared with the normal values for adults. The clinical evaluations were made using the ankle-hindfoot score and the midfoot score of the American Orthopaedic Foot and Ankle Society (AOFAS): excellent (>85), good (71-85), pair (56-70), and poor (<56). Results: At the last follow-up, the percentages of the 51 cases, whose parameter values fell within the normal ranges were as follows: in the AP view, 41.2% (talocalcaneal angle); and 90.2% (talo-first metatarsal angle). In the lateral view, the percentage was 84.3% (talocalcaneal angle). For the calcaneal pitch, the percentages were 61%. The mean AOFAS score was 88.1±10.7 on the ankle-hindfoot score and 86.7±11.5 on the midfoot score. Conclusion: The long-term outcome of patients with idiopathic clubfoot, who underwent surgical treatment after conservative treatment, was found to be 43%-90% of the normal range of radiographic indices. Clinically, the mean AOFAS scores were "excellent". Therefore, a satisfactory result can be obtained by analyzing the elements of deformity more accurately and then using the selective operation method, even if the non-surgical correction method fails.

• Korean Journal of Poultry Science
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• v.50 no.3
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• pp.171-185
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• 2023

This study was conducted to investigate the effects of supplementation of Allium hookeri (AH) root powder on the gut microbiome, immunity, and health in broiler chickens fed experimental diets from d 10 to 28. A total of 60 10-day-old Ross 308 broilers were weighed and assigned to two dietary treatments with 5 birds per cage in a randomized complete block design based on body weight. The two experimental diets consisted of a control diet based on corn-soybean meal and the control diet supplemented with 0.3% AH root powder. All birds were fed ad libitum with experimental diets and water for 18 d. At 28 d, two birds near the median weight from each cage were selected for cecal content and small intestinal tissue sample collection. The addition of AH changed the gut microbiome by increasing probiotic candidate beneficial bacteria such as Enterococcaceae, Lactobacillaceae, Limosilactobacillus, Cuneatibacter, and Ruminoccoides. Regarding gut immunity, the supplementation of AH resulted in changes in intestinal immune cells, including reduced CD3+CD4+ T cells, which are a type of helper T cell, in the small intestine of birds (P=0.049). Additionally, there was a tendency to increase the expression of antioxidant function-related gene such as GPX2 (P=0.060), but no significant changes were observed in cytokines such as IL1b, IL6, and IL10. Overall, the addition of AH root powder may have positive effects on the microbiome of the chickens. This may help promote gut health in broiler chickens at the age of d 10 to 28.

• Journal of Life Science
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• v.33 no.11
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• pp.923-935
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• 2023

Rubus crataegifolius (RC), Ulmus macrocarpa (UM), and Gardenia jasminoides (GJ) are well-known folk medicines in Asia used to treat various gastrointestinal disturbances. The present study evaluated the gastroprotective effect of LS-RUG-com, a mixture of commercially prepared powders of RC, UM, and GJ with a ratio of 3:1:2(w/w/w) against HCl/ethanol-induced gastritis, indomethacin-induced ulcers, and esophageal reflux-induced esophageal mucosal damage and Helicobacter pylori infections. In addition, TNF-α and IL-1β expressions were also determined and measured in esophageal tissue. As to HCl/ethanol-induced gastritis, the LS-RUG-com treatment at a dose of 150 mg/kg showed a remarkable anti-gastritis effect. Regarding indomethacin-induced gastric ulcers, the LS-RUG-com treatment had a significant anti-gastric ulcer effect. Furthermore, in the gastroesophageal reflux disease (GERD) model experiment, the LS-RUG-com treatment resulted in the histological recovery of stomach damage and mucosal injuries. Furthermore, the LS-RUG-com treatment led to an increase in gastric content pH, an increase in mucus protection, and a decrease in gastric pepsin output with a significant decrease in TNF-α and IL-1β. As to the Helicobacter pylori infected animal model, LS-RUG-com had a notable inhibitory effect on Helicobacter growth. The use of RC, UM, or GJ in isolation or the LS-RUG-com treatment as whole had good effects in terms of anti-oxidation, anti-neutralization, gastric acid secretion inhibition, and anti-lipid peroxidation, which supported the use of natural products as systemic gastric protective agents. Our results suggest that the LS-RUG-com might be a significant systemic gastroprotective agent that could be utilized for the treatment and/or protection from gastric disturbances and related damage.

• Journal of Mushroom
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• v.21 no.4
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• pp.254-260
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• 2023

The characteristics and spore production of Gonji7ho, Bunhong, and Sunjung fruiting bodies were assessed at different growth stages. The shape of the Pleurotus species fruiting body starts out short and small, then takes on a typical mushroom shape as it grows. Gonji7ho has a long stalk, Bunhong has a short stalk and a wide cap, and Sunjung's cap and stalk dimensions are intermediate. Each variety displayed deep color at the beginning of growth but became steadily lighter with continued growth. The shape of the linkage between the mushroom stalk and cap changed from an initial central position to a lateral position after the growing stage. Gonji7ho cap diameter increased 7-fold from 15.5 mm (5 days of growth) to 37.9 mm (9 days of growth). Growth rates for each growth day measured using the growth percentage of the previous day were 285.5% (5 → 6th day), 182.2% (6 → 7th day), 129.4% (7 → 8th day), and 103.8% (8 → 9th day). This trend was also observed in Bunhong and Sunjung, but Bunhong's growth rate was more rapid (4.9 fold on day 6, 2.7 fold on day 7) and continued to increase through day 9. Harvest yield, which is of greatest interest to farmers, displayed a similar trend spanning the growth period, as did cap diameter. Gonji7ho harvest yield increased rapidly until day 7 of growth (more than 177%), then growth slowed down beginning around day 8, and further decreased on day 9 (98%). Similar trends were observed in Bunhong and Sunjung. Bunhong showed characteristic rapid growth in harvest yield (4.9 fold compared to the previous day on day 6 and 2.7 fold on day 7), and the increase continued through day 9. A decrease in mushroom harvest yield commonly seen in the late growth stage is thought to be due to the death of some mushrooms and decomposition of cap tissue. Basidiospore content increased with number of growth days but decreased after day 8. Gonji7ho yielded the highest production on day 7 of growth, coinciding with harvest time, with 209,000,000 spores. This trend was also observed in Bunhong and Sunjung. These results will provide researchers with basal data and guide farmers in selecting the optimal harvest day.

• Journal of the Korean Society of Radiology
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• v.82 no.3
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• pp.562-574
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• 2021

MRI has the advantages of having excellent soft-tissue contrast and providing functional information without any harmful ionizing radiation. Although previous technical limitations restricted the use of chest MRI, recent technological advances and expansion of insurance coverage are increasing the demand for chest MRI. Recognizing the need for guidelines on appropriate use of chest MRI in Korean clinical settings, the Korean Society of Radiology has composed a development committee, working committee, and advisory committee to develop Korean chest MRI justification guidelines. Five key questions were selected and recommendations have been made with the evidence-based clinical imaging guideline adaptation methodology. Recommendations are as follows. Chest MRI can be considered in the following circumstances: for patients with incidentally found anterior mediastinal masses to exclude non-neoplastic conditions, for pneumoconiosis patients with lung masses to differentiate progressive massive fibrosis from lung cancer, and when invasion of the chest wall, vertebrae, diaphragm, or major vessels by malignant pleural mesothelioma or non-small cell lung cancer is suspected. Chest MRI without contrast enhancement or with minimal dose low-risk contrast media can be considered for pregnant women with suspected pulmonary embolism. Lastly, chest MRI is recommended for patients with pancoast tumors planned for radical surgery.