1.Aquatic Toxicity Assessment of Phosphate Compounds.
Eunju KIM ; Sunkyoung YOO ; Hee Young RO ; Hye Jin HAN ; Yong Wook BAEK ; Ig Chun EOM ; Hyun Mi KIM ; Pilje KIM ; Kyunghee CHOI
Environmental Health and Toxicology 2013;28(1):e2013002-
OBJECTIVES: Tricalcium phosphate and calcium hydrogenorthophosphate are high production volume chemicals, mainly used as foodstuff additives, pharmaceuticals, lubricants, synthetic resin, and disinfectants. Phosphate has the potential to cause increased algal growth leading to eutrophication in the aquatic environment. However, there is no adequate information available on risk assessment or acute and chronic toxicity. The aim of this research is to evaluate the toxic potential of phosphate compounds in the aquatic environment. METHODS: An aquatic toxicity test of phosphate was conducted, and its physico-chemical properties were obtained from a database recommended in the Organization for Economic Cooperation and Development (OECD) guidance manual. An ecotoxicity test using fish, Daphnia, and algae was conducted by the good laboratory practice facility according to the OECD TG guidelines for testing of chemicals, to secure reliable data. RESULTS: The results of the ecotoxicity tests of tricalcium phosphate and calcium hydrogenorthophosphate are as follows: In an acute toxicity test with Oryzias latipes, 96 hr 50% lethal concentration (LC50) was >100 (measured:>2.14) mg/L and >100 (measured: >13.5) mg/L, respectively. In the Daphnia test, 48 hr 50% effective concentration (EC50) was >100 (measured: >5.35) mg/L and >100 (measured: >2.9) mg/L, respectively. In a growth inhibition test with Pseudokirchneriella subcapitata, 72 hr EC50 was >100 (measured: >1.56) mg/L and >100 (measured: >4.4) mg/L, respectively. CONCLUSIONS: Based on the results of the ecotoxicity test of phosphate using fish, Daphnia, and algae, L(E)C50 was above 100 mg/L (nominal), indicating no toxicity. In general, the total phosphorus concentration including phosphate in rivers and lakes reaches levels of several ppm, suggesting that phosphate has no toxic effects. However, excessive inflow of phosphate into aquatic ecosystems has the potential to cause eutrophication due to algal growth.
Calcium
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Daphnia
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Disinfectants
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Ecosystem
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Eutrophication
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Lakes
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Lubricants
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Oryzias
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Phosphorus
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Resins, Synthetic
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Risk Assessment
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Rivers
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Toxicity Tests
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Toxicity Tests, Acute
2.Osteochondrodysplasia in three Scottish Fold cats.
Jinhwa CHANG ; Joohyun JUNG ; Sunkyoung OH ; Sungok LEE ; Gyeongmin KIM ; Haksang KIM ; Ohkyeong KWEON ; Junghee YOON ; Mincheol CHOI
Journal of Veterinary Science 2007;8(3):307-309
This report explains typical radiographic features ofScottish Fold osteochondrodysplasia. Three Scottish Foldcats suffering from lameness were referred to theVeterinary Medical Teaching Hospital, Seoul NationalUniversity, Korea. Based on the breed predisposition,history, clinical signs, physical examination, and radiographicfindings, Scottish Fold osteochondrodysplasia was confirmedin three cases. Radiographic changes mainly includedexostosis and secondary arthritis around affected jointlesions, and defective conformation in the phalanges andcaudal vertebrae. The oral chondroprotective agents suchas glucosamine and chondroitin sulfate make the patientsalleviate their pain without adverse effects.
Animals
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Anti-Inflammatory Agents, Non-Steroidal/therapeutic use
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Cat Diseases/drug therapy/*radiography
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Cats
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Female
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Lameness, Animal/drug therapy/radiography
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Osteochondrodysplasias/drug therapy/radiography/*veterinary
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Thiazines/*therapeutic use
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Thiazoles/*therapeutic use
3.A new 3, 4-epoxyfurocoumarin from Heracleum moellendorffii Roots.
Sang Yeol PARK ; Nara LEE ; SunKyoung LEE ; Myong Jo KIM ; Wanjoo CHUN ; Hyun Pyo KIM ; Hee Jung YANG ; Ho Sun LEE ; Yongsoo KWON
Natural Product Sciences 2017;23(3):213-216
Activity-guided isolation of Heracleum moellendorffii roots led to four coumarin derivatives as acetylcholinesterase inhibitors. The structures of these isolates were characterized by spectroscopic method to be angelicin (1), isobergapten (2), pimpinellin (3), and (3S, 4R)-3, 4-epoxypimpinellin (4). All the isolated compounds 1, 2, 3, and 4 showed moderate inhibition activities against acetylcholinesterase with the IC₅₀ values of 10.2, 18.1, 21.5 and 22.9 µM, respectively. (3S, 4R)-3, 4-Epoxypimpinellin (4) was newly isolated from the plant source.
Acetylcholinesterase
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Cholinesterase Inhibitors
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Coumarins
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Heracleum*
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Methods
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Plants
4.Effect of Mass Drug Administration with a Single Dose of Albendazole on Ascaris lumbricoides and Trichuris trichiura Infection among Schoolchildren in Yangon Region, Myanmar
Jong-Yil CHAI ; Woon-Mok SOHN ; Sung-Jong HONG ; Bong-Kwang JUNG ; Sooji HONG ; Seon CHO ; Jong-Bok PARK ; In-Sung KIM ; Sunkyoung KIM ; Keon-Hoon LEE ; Hoo-Gn JEOUNG ; Thi Thi HTOON ; Htay Htay TIN
The Korean Journal of Parasitology 2020;58(2):195-200
Soil-transmitted helminths, including Ascaris lumbricoides and Trichuris trichiura, are important intestinal parasites mostly affecting younger people in developing countries. In 2014-2015, we performed mass fecal examinations targeting a total of 2,227 schoolchildren in 3 districts (South Dagon, North Dagon, and Hlaing-thar-yar) of Yangon Region, Myanmar, using the Kato-Katz thick smear technique. The egg positive children were subjected to a mass drug administration (MDA) using a single oral dose of 400 mg albendazole. The pre-treatment egg positive rate (EPG/person) of A. lumbricoides averaged 17.2% (15,532); it was 25.2% (21,796), 14.2% (11,816), and 12.8% (12,983) in 3 districts, respectively, and that of T. trichiura averaged 19.4% (1,074), and was 24.1% (1,040), 12.3% (852), and 21.2% (1,330) in 3 districts, respectively. Follow-up fecal examinations performed 4 months post-MDA revealed considerable decreases of A. lumbricoides prevalence (EPG/person) to av. 8.3% (12,429), and 13.7% (17,640), 8.0% (7,797), and 4.5% (11,849) in 3 districts, respectively. However, T. trichiura did not show any recognizable decrease in the prevalence (EPG/person) remaining at av. 18.2% (862), and 18.5% (888), 11.5% (812), and 23.3% (887) in 3 districts, respectively. The results demonstrated difficulty in short-term control of T. trichiura by MDA using albendazole and suggested necessity of either a long-term MDA (>10 years) or changing the albendazole regimen into 2~3-day course (total 800 or 1,200 mg), or using an alternative drug/drug combination.