http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Jinhee Choi(Jinhee Choi) 한국환경성돌연변이발암원학회 2001 한국환경성돌연변이·발암원학회지 Vol.21 No.2
Effects of exposure to a neurotoxicant, fenitrothion on antioxidant enzyme activities in Chironomus riparius Mg. (Diptera, Chironomidae) larvae were evaluated under laboratory conditions. Exposure to this chemical led to an increase of cupper, zinc type superoxide dismutase and manganese type superoxide dismutase activities and to a decrease of glutathion peroxidase activity. An activation of catalase was observed in the larvae exposed to high fenitrothion concentration. The response of superoxide dismutase was rapid and sensitive to low chemical concentrations, but changes in catalase, total peroxidase and glutathion peroxidase were less sensitive. In this study, antioxidant enzyme activities in Chironomus riparius larvae were identified as pertinent biomarkers for environmental monitoring.
Fabrication of CuSn Nanofibers Prepared via Electrospinning
Choi, Jinhee,Park, Juyun,Choi, Ahrom,Lee, Seokhee,Koh, Sung-Wi,Kang, Yong-Cheol The Basic Science Institute Chosun University 2017 조선자연과학논문집 Vol.10 No.4
The Cu and CuSn/PVP nanofibers were fabricated by electrospinning method by controlling various parameters. The precursor solution was prepared with copper(II) acetate monohydrate ($Cu(CH_3COO)_2$) and tin chloride dihydrate ($SnCl_2{\cdot}2H_2O$), and polyvinylpyrrolidone (PVP) for adjusting viscosity. The fabricated nanofibers were calcined at 873 K in Ar atmospheric environment for 5 hours to remove the solvent and polymer. The morphology and diameter of nanofibers were measured by optical microscopy (OM) with Motic image plus 2.0 program. The components and chemical environment were investigated with X-ray photoelectron spectroscopy (XPS). From the XPS survey spectra, we confirmed that CuSn/PVP nanofibers were successfully fabricated. The XPS peaks of C 1s and N 1s were remarkably decreased after calcination of the nanofibers at 873 K. It implies that the PVP was completely decomposed after calcination at 873 K.
Antioxidant and apoptotic activity of cocoa bean husk extract on prostate cancer cells
Choi Jinhee,Yang Changwon,Lim Whasun,Song Gwonhwa,최해연 대한독성 유전단백체 학회 2022 Molecular & cellular toxicology Vol.18 No.2
Background Although prostate cancer is the most commonly diagnosed cancer in men, its incidence among Asians, who consume foods rich in phenols, is relatively low compared with that in other populations. Cocoa bean husk (CBH) is an important by-product of the cocoa industry; its polyphenol content (catechin, epicatechin, and procyanidin B) is as high as that of cocoa beans. However, there are no studies on the anticancer effect of CBH. Herein, we assessed the antioxidant and anticancer effects of CBH on prostate cancer cells. Objectives We fractionated CBH ethanol crude extract and compared the total polyphenol content, total flavonoid content, and DPPH and ABTS + radical scavenging activities of the fractions. Catechin, epicatechin, and procyanidin B were analysed by HPLC in the ethyl acetate (EAF) and butanol (BF) fractions, which had the highest physiological content and antioxidant activity. PC3 and DU145 cells were treated with the two fractions, and annexin V/propidium iodide, and TUNEL assays were performed to assess apoptosis and DNA fragmentation, respectively. Results The highest phytochemical content and antioxidant activity were observed in EAF, followed by those in BF. HPLC analysis revealed high content of phenolic compounds in both these fractions. Notably, catechin (5.64 mg/g), epicatechin (20.47 mg/g), and procyanidin B (20.29 mg/g) were abundant in EAF. Both fractions induced apoptosis in a concentrationdependent manner in PC3 and DU145 cells, and DNA fragmentation at a concentration of 200 μg/mL. Conclusion CBH, a by-product of cocoa processing, contains large amounts of phenolic compounds and exhibits high antioxidant activity and anticancer effects on prostate cancer cells. CBH has potential applications as a functional food material.
Jinhee Choi 한국독성학회 2008 Toxicological Research Vol.24 No.4
While in some instances, loss of diversity results from acute toxicity (e.g. major pollution incidents), in most cases it results from long-term sub-lethal effects that alter the relative competitive ability and fitness of certain organisms. In such cases the sub-lethal effects will cause a physiological response in the organism that ultimately leads to community level changes. Very sensitive tools are now available to study sub-lethal responses at the molecular level. However, relating such laboratory measurements to ecological effects represents a substantial challenge that can only be met by investigation at all scales (molecular, individual organism and community level) with an appropriate group of organisms. Among the various in vertebrates which can be used as model organisms in such a way, the soil nematode, Caenorhabditis elegans appear to be a promising biological model to diagnose environmental quality. This paper reviews the current status of multilevel biomarkers in environmental toxicology, and C. elegans as promising organisms for this approach.