국내 시판 어린이 점토제품 중 보존제 함유량 조사

정선혜(Sun Hye Jung),허진영(Jin Yeong Heo),오지희(Ji Hee Oh),박나연(Na-Youn Park),고영림(Younglim Kho) 한국환경보건학회 2022 한국환경보건학회지 Vol.48 No.1

Background: Preservatives are used to prevent product deterioration in modeling clay. Parabens, a representative preservative, have been found to be endocrine disruptors and cause skin irritation and allergic reactions. Isothiazolinone preservatives can be irritating to the skin, respiratory tract, and eyes. Thorough investigation and regulation of clay are necessary because clay is marketed to children, who are more sensitive to the toxic effect of chemicals. Objectives: In this study, the presence of 16 preservatives was analyzed in modeling clay and the results were compared with current standards. Methods: A total of 200 samples were collected from 28 children’s clay products sold in South Korea (13 from Korea and 15 imported from overseas). Twelve preservatives, such as parabens, were analyzed using high- performance liquid chromatography (HPLC). Isothiazolinone preservatives (chloromethylisothiazolinone; CMIT, methylisothiazolinone; MIT, octylisothiazolinone; OIT, and benzisothiazolinone; BIT) were analyzed using ultra performance liquid chromatography-tandem mass spectrometery (UPLC-MS/MS). Results: Dehydroacetic acid (DHA) was detected the most in the clays at 51.50% (103 cases) detection; 38 cases (median 190.42 μg/g) in Korean products and 65 cases (median 169.62 μg/g) in Chinese products. CMIT, which is prohibited in Korea, was detected in 14 (median 16.28 μg/g) Chinese products. OIT, which has a chemical structure similar to CMIT was found in 28 (median 68.38 μg/g) samples in Korean products. Conclusions: The use of CMIT and MIT in children s products is prohibited in Korea and the European Union (EU). The detection of CMIT in Chinese clay products suggests that management is necessary for imported products. It is necessary to review the safety and regulatory status for OIT because OIT was used as a substitute for CMIT and MIT in Korean products.

백지에서 추출한 oxypeucedanin hydrate의 미토콘드리아 기능 관련 근생성 효과

송은주(Eun-Ju Song),허지원(Ji-Won Heo),장지희(Jee Hee Jang),권윤주(Yoon-Ju Kwon),정윤희(Yun Hee Jeong),김민정(Min Jung Kim),김성은(Sung-Eun Kim) 한국영양학회 2024 Journal of Nutrition and Health Vol.57 No.1

Purpose: Mitochondria play a crucial role in preserving skeletal muscle mass, and damage to mitochondria leads to muscle mass loss. This study investigated the effects of oxypeucedanin hydrate, a furanocoumarin isolated from Angelica dahurica radix, on myogenesis and mitochondrial function in vitro and in zebrafish models. Methods: C2C12 myotubes cultured in media containing 0.1, 1, 10, or 100 ng/mL oxypeucedanin hydrate were immunostained with myosin heavy chain (MHC), and then multinucleated MHC-positive cells were counted. The expressions of markers related to muscle differentiation, muscle protein degradation, and mitochondrial function were determined by quantitative reverse transcription polymerase chain reaction. To investigate the effects of oxypeucedanin hydrate on mitochondrial dysfunction, Tg(Xla.Eef1a1:mito-EGFP) zebrafish embryos were treated with 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI) with or without oxypeucedanin hydrate and analyzed for mito-EGFP intensity and mitochondrial length. Results: Oxypeucedanin hydrate significantly increased MHC-positive multinucleated myotubes (≥ 3 nuclei) and increased the expression of the myogenic marker myosin heavy chain 4. However, it decreased the expressions of muscle-specific RING finger protein 1 and muscle atrophy f-box (markers of muscle protein degradation). Furthermore, oxypeucedanin hydrate enhanced the expressions of markers of mitochondrial biogenesis (peroxisome proliferator-activated receptor-gamma coactivator 1 alpha, transcription factor a mitochondrial, succinate dehydrogenase complex flavoprotein subunit A, and cytochrome c oxidase subunit 1) and mitochondrial fusion (optic atrophy 1). However, it reduced the expression of dynamin-related protein 1 (a mitochondrial fission regulator). Consistently, oxypeucedanin hydrate reduced FOLFIRI-induced mitochondrial dysfunction in the skeletal muscles of zebrafish embryos. Conclusion: The study indicates that oxypeucedanin hydrate promotes myogenesis by improving mitochondrial function, and thus, suggests oxypeucedanin hydrate has potential use as a nutritional supplement that improves muscle mass and function.

길경에서 추출한 polygalacin D가 근원세포 분화 및 근위축에 미치는 영향

송은주(Eun-Ju Song),허지원(Ji-Won Heo),장지희(Jee Hee Jang),김언미(Eonmi Kim),정윤희(Yun Hee Jeong),김민정(Min Jung Kim),김성은(Sung-Eun Kim) 한국영양학회 2023 Journal of Nutrition and Health Vol.56 No.6

Purpose: The balance between synthesis and degradation of proteins plays a critical role in the maintenance of skeletal muscle mass. Mitochondrial dysfunction has been closely associated with skeletal muscle atrophy caused by aging, cancer, and chemotherapy. Polygalacin D is a saponin derivative isolated from Platycodon grandiflorum (Jacq.) A. DC. This study aimed to investigate the effects of polygalacin D on myoblast differentiation and muscle atrophy in association with mitochondrial function in in vitro and in zebrafish models in vivo. Methods: C2C12 myoblasts were cultured in differentiation media containing different concentrations of polygalacin D, followed by the immunostaining of the myotubes with myosin heavy chain (MHC). The mRNA expression of markers related to myogenesis, muscle atrophy, and mitochondrial function was determined by real-time quantitative reverse transcription polymerase chain reaction. Wild type AB* zebrafish (Danio rerio) embryos were treated with 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI) with or without polygalacin D, and immunostained to detect slow and fast types of muscle fibers. The Tg(Xla.Eef1a1:mito-EGFP) zebrafish expressing mitochondria-targeted green fluorescent protein was used to monitor mitochondrial morphology. Results: The exposure of C2C12 myotubes to 0.1 ng/mL of polygalacin D increased the formation of MHC-positive multinucleated myotubes (≥ 8 nuclei) compared with the control. Polygalacin D significantly increased the expression of MHC isoforms (Myh1, Myh2, Myh4, and Myh7) involved in myoblast differentiation while it decreased the expression of atrophic markers including muscle RING-finger protein-1 (MuRF1), mothers against decapentaplegic homolog (Smad)2, and Smad3. In addition, polygalacin D promoted peroxisome proliferatoractivated receptor-gamma coactivator (Pgc1α) expression and reduced the level of mitochondrial fission regulators such as dynamin-1-like protein (Drp1) and mitochondrial fission 1 (Fis1). In a zebrafish model of FOLFIRI-induced muscle atrophy, polygalacin D improved not only mitochondrial dysfunction but also slow and fast muscle fiber atrophy. Conclusion: These results demonstrated that polygalacin D promotes myogenesis and alleviates chemotherapy-induced muscle atrophy by improving mitochondrial function. Thus, polygalacin D could be useful as nutrition support to prevent and ameliorate muscle wasting and weakness.

임신 중 자궁 근세포 내에서 cytokine들이 matrix metalloproteinase-9 을 발현시키는 신호전달체계에 관한 연구

서용수(Yong Soo Seo),백금희(Geum Hee Baek),허지희(Ji Hee Heo),양순하(Soon Ha Yang),김종화(Jong Hwa Kim),배덕수(Duk Soo Bae),노정래(Cheong Rae Roh) 대한산부인과학회 2001 Obstetrics & Gynecology Science Vol.44 No.5

N/A Objective : To explore the intracellular signal transduction pathways of IL-1β and TNF-α in inducing matrix metalloproteinase-9 (MMP-9) in human myometrial smooth muscle cells. Methods : We studied the expression of MMP-9 induced by cytokines (TNF-α and IL-1β) with zymography. The influence of TNF-α and IL-1β on the phosphorylation of Jun N-terminal kinase (JNK) and IkB were studied with immunoblotting for p-JNK and p-IkB. The intranuclear shifting of NF-kB and AP-1 after treatment with TNF-α and IL-1β were evaluated by EMSA. Results : TNF-α- and IL-1β-induced MMP-9 expression was not suppressed by NF-kB inhibitor (CAPE), AP-1 inhibitor (curcumin) and PKC inhibitor (calphostin C) but was inhibited by tyrosine kinase inhibitor (genistein). After treatment of myometrial smooth muscle cells with TNF-α and IL-1β, phosphorylation of JNK and phosphorylation of IkB with degradation of IkB were evidently observed. The intranuclear translocations of NF-kB and AP-1 were strongly enhanced after treatment with TNF-α and IL-1β as demonstrated in EMSA. Conclusion : In myometrial smooth muscle cells, MMP-9 is induced by TNF-α and IL-1β through PKC activation and transcriptional activations of NF-kB and AP-1. Independent of PKC activation, the signaling of TNF-α and IL-1β in the induction of MMP-9 seems to be transmitted by way of either NF-kB or AP-1 activation in myometrial smooth muscle cells.

도시내 배송차량의 운영최적화

문기주,허지희 東亞大學校 經營問題硏究所 2001 經營論叢 Vol.22 No.-

A procedure for solving vehicle routing problems is important to reduce the logistics cost and to enhance the overall performance of the enterprise system. In this study we investigated vehicle routing problems under three different vehicle speeds. An efficient heuristic which can consider the dynamic environment is developed and examined with various problems. In this environment the moving speed between two points is not the same all the time. The speed is determined based on the time that the vehicle actually passes. It is found that the developed heuristic can be used to find an optimum or near optimum vehicle route by simulation studies.