• Title/Summary/Keyword: $MS^n$

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Determination of benzophenone in water, soil and sediment by gas chromatography/mass spectrometry (기체크로마토그래피/질량분석기에 의한 수질, 토양 및 저질 시료중의 benzophenone 분석법에 관한 연구)

  • Jeon, Hee Kyung;Choi, Hae Yeon;Ryu, Jae-Chun
    • Analytical Science and Technology
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    • v.18 no.2
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    • pp.147-153
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    • 2005
  • Benzophenone (BP) which is one of endocrine disrupting chemicals is suspected to contaminate waters (river, lake and industrial drainage) and soils (ground soil and sediment). Analytical method for determination of BP in soil and water was developed by gas chromatography/mass spectrometry. Water sample (100 mL) was extracted with n-hexane, and soil (10 g) was extracted with methanol and n-hexane. Recovery for BP was >71.4% in water and 86.5-94.7% in soil with coefficient variation of less than 19.8%. Calibration curves showed a good linearity ($r^2$ >0.998). In water, soil and sediment collected at nation-wide sites, BP was detected at 5 sites among 43 water sites at the concentration range of 30-200 ng/L. No BP was found in the soil and sediment samples. It is suggested that this method will be useful to the determination of BP in the environmental matrices such as waters, soils and sediments in minute quantities.

Studies on the Constituents of Spiraea Koreana Nakai (참조팝나무의 成分 Alkaloid 에 關한 硏究)

  • Jin, Kab-Dukc
    • Journal of the Korean Chemical Society
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    • v.11 no.3
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    • pp.111-116
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    • 1967
  • A new alkaloid named Spirajine(m.p. 182~$184^{\circ}C$ $[{\alpha}]d^{19}+3.4^{\circ}$ in $CHCl_3$, $C_{23}H_{33}NO_3$, colorless prism) was isolated from the leaves of Spiraea Koreana Nakai (Spiraeceae) (Korean name "Chamjopab namu") which grows in the mountaineous area of Korea, by process of Scheme I (yields 0.13%). Another two unidentified alkaloids (not yet crystallized) were separated by the method of thin layer chromatography. (The Rf values of the two unidentified alkaloids were 0.66, 0.77, respectively and Spirajine 0.72) Spirajine were subjected to the structural investigation with the use of ultra violet and infra red spectrophotometry, and opical rotatory dispersion. The alkaloid contains two ketonic carbonyl groups, tertiary hydroxyl group, methyl groups, N-methyl group and both cyclohexane ring and cyclopentane ring.

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Purification and Identification of Antioxidant Compounds from Dolichos lablab L. Seeds (백편두의 항산화 물질 분리 및 동정)

  • Kwon, Nam Woo;Kim, Jae Yeon;Cho, Yong Beom;Hwang, Bang Yeon;Kim, Jun Gu;Woo, Sun Hee;Lee, Moon Soon
    • Korean Journal of Medicinal Crop Science
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    • v.27 no.6
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    • pp.419-426
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    • 2019
  • Background: This study aimed to identify antioxidant compounds from the seeds of Dolichos lablab L. by bioassay-guided isolation and recrystallization. Methods and Results: The water layer of D. lablab L. seed extract inhibits intracellular reactive oxygen species (ROS) expressing the 2',7'-dichlorofluorescein diacetate (DCF-DA), Cu/Zn superoxide dismutase (SOD) and catalase genes, as determined by quantitative real-time PCR (qRT-PCR). Two compounds were purified from the water layer of the seeds of D. lablab L. using column chromatography and prep-high performance liquid chromatography (HPLC). Using nuclear magnetic resonance (NMR) and electrospray Ionization mass spectrometry (ESI-MS), their chemical structures were identified as 5-[(2-acetyl-2,3-dihydro-1H-indazol-1-yl)carbonyl]-4,5-dihydro-3H-furan-2-one (C14H14N2O4) and stachyose. Conclusions: Two active antioxidant compounds were purified from the seed extract of D. lablab L. seed extract and the structures of these compounds were identified as C14H14O4N2 and stachyose.

ROLE OF SYMPATHETIC NERVE ON THE CONTROL OF MICROCIRCULATION IN THE FELINE DENTAL PULP (고양이 치수에서 교감신경에 의한 미세순환조절에 관한 기능적 연구)

  • Kim, Sung-Kyo
    • Restorative Dentistry and Endodontics
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    • v.21 no.1
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    • pp.375-384
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    • 1996
  • The purpose of this study was to investigate the functional involvement of sympathetic nerve in the control of the microcirculation in the dental pulp with the aim of elucidation of the involvement of neuropeptides and sympathetic nerve in neurogenic inflammation. Experiments were done on the 7 cats anesthetised with sodium pentobarbital, and sympathetic nerve to the' dental pulp was stimulated electrically (10 Hz, 4 V, 1.5 ms, 3.5 mins). Ana-adrenoceptor antagonist phentolamine and a neuropeptide Y antagonist D-myo-inositol-1,2,6-trisphosphate (PP56) were injected close intra-arterially into the dental pulp without changing the systemic blood pressure. The probe of laser Doppler flowmeter was placed on the buccal surface of ipsilateral canine teeth to the stimulation, and pulpal blood flow was measured. Stimulation of the sympathetic nerve decreased pulpal blood flow by $55.24{\pm}7.74\;%$ (mean${\pm}$SEM, n = 13). Stimulation of the sympathetic nerve following the injection of the ${\alpha}$-adrenoceptor antagonist phentolamine ($0.1{\mu}g$/kg) caused decrease of pulpal blood flow by $14.35{\pm}3.43%$ (mean${\pm}$SEM, n=5). Phentolamine attenuated the sympathetic nerve-induced pulpal blood flow decrease by $74.02{\pm}9.32%$ (mean${\pm}$SEM) Stimulation of the sympathetic nerve following the injection of the neuropeptide Y antagonist PP56 (2.3 mg/kg) caused decrease of pulpal blood flow by $30.64{\pm}7.92%$ (mean${\pm}$SEM, n=6). PP56 attenuated the sympathetic nerve-induced pulpal blood flow decrease by $44.37{\pm}11.01%$ (mean${\pm}$SEM). These data provide evidences of the co-contribution of nerepinephrine and neuropeptide Y on the sympathetic nerve-induced vasoconstriction in the feline dental pulp. In addition, they show functional evidences that sympathetic nerve plays an active role in controlling the microcirculation of the dental pulp.

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Expression of the Green Fluorescent Protein (GFP) in Tobacco Containing Low Nicotine for the Development of Edible Vaccine

  • Kim Young-Sook;Kim Mi-Young;Kang Tae-Jin;Kwon Tae-Ho;Jang Yong-Suk;Yang Moon-Sik
    • Journal of Plant Biotechnology
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    • v.7 no.2
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    • pp.97-103
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    • 2005
  • This study was carried out to obtain basic information for gene manipulation in potent edible tobacco (Nicotiana tabacum cv. TI 516). N. tabacum cv. TI 516 is a plant for a possible candidate to use as an edible vaccine, since it contains a low level of nicotine. The effective plant regeneration system through leaf disc culture was achieved using a MS basal medium supplemented with 0.1 mg $1^{-1}$ NAA and 0.5 mg $1^{-1}$ BA. In order to transform the N. tabacum cv. TI 516 with the green fluorescent protein (GFP) gene, Agrobacterium tumefaciens LBA 4404 containing the GFP gene was used. Genomic PCR confirmed the integration of the GFP gene into nuclear genome of transgenic plants. Expression of the GFP gene was identified in callus, apical meristem and root tissue of transgenic N. tabacum cv. TI 516 plants using fluorescence microscopy. Western blot analysis revealed the expression of GFP protein in the transgenic edible tobacco plants. The amount of GFP protein detected in the transgenic tobacco plants was approximately 0.16% of the total soluble plant protein (TSP), which was determined by ELISA.

Effect of Torilis Fructus on Procollagen Biosynthesis and Activity of Matrix Metalloproteinase-I(MMP-1) in Human Dermal Fibroblast (사상자(Torilis Fructus)가 섬유아세포의 Procollagen 생합성과 Matrix metalloproteinase-I(MMP-1)의 활성에 미치는 영향)

  • Koo, Bon-Suk;Hwang, Eui-Il;So, Seung-Ho;Lee, Seong-Kye;Han, Gyeong-Ho;Kim, Na-Mi
    • Korean Journal of Pharmacognosy
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    • v.38 no.4
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    • pp.349-353
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    • 2007
  • Skin wrinkle formations are associated with collagen synthesis and matrix metalloproteinase-I(MMP-1) activity. This study was carried out to find out skin wrinkle reducing components in Torilis Fructus. Torilis Fructus were extracted with 70% ethanol and the ethanol extracts were systematically fractionated with n-hexane, ethylacetate, n-butanol and distilled water. Among them, antiwrinkle component from n-hexane fraction was purified by several column chromatographies and HPLC, which identified as torilin by $^1H-NMR,\;^{13}C-NMR$ and ESI-MS. To determine cell viability, collagen biosynthesis and MMP-1 activity, human dermal fibroblast was treated with 1-5 ppm concentrations of Torilis Fructus extract fraction and torilin. Cell viability was showed 84-102% at all group treated with 1-5 ppm. Collagen synthesis was increased in all group, especially torilin-treated group was highest amount. Active forms of MMP-1 were decreased in all group. From these results, we consider that Torilis Fructus have several antiwrinkle components and torilin may be one of the effective components.

Cytotoxic Effect of Flavonoids from the Roots of Glycyrrhiza uralensis on Human Cancer Cell Lines (감초(Glycyrrhiza uralensis Fisch.)로부터 분리된 flavonoid의 인체 암세포에 대한 세포독성)

  • Park, Ji-Hae;Wu, Qian;Yoo, Ki-Hyun;Yong, Hye-Im;Cho, Sueng-Mock;Chung, In-Sik;Baek, Nam-In
    • Journal of Applied Biological Chemistry
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    • v.54 no.1
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    • pp.67-70
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    • 2011
  • The roots of Glycyrrhiza uralensis Fisch. were extracted with 30% aqueous ethanol (EtOH), and the concentrated extract was partitioned with n-hexane, chloroform ($CHCl_3$), ethyl acetate (EtOAc), n-butanol (n-BuOH), and $H_2O$, successively. From the $CHCl_3$ fraction, four flavonoids were isolated through the repeated silica gel ($SiO_2$), octadecyl silica gel (ODS), and Sephadex LH-20 column chromatographies (c.c.). According to the results of spectroscopic data including nuclear magnetic resonance spectrometry (NMR), electron ionization mass spectrometry (EI/MS), and infrared spectroscopy (IR), the chemical structures of the compounds were determined as glabrol (1), abyssinone II (2), glabridin (3), and isoliquiritigenin (4). The flavonoids were evaluated for cytotoxic effect against human cancer cell lines, HCT-116, HepG2, HeLa, SK-OV-3, SK-BR-3, MCF-7, and SK-MEL-5. Especially, glabrol (1) and glabridin (2) showed $IC_{50}$ values of lower than $25{\mu}M$.

Biosynthesis of Eudesmane-type Sesquiterpenoids by The Wood-rotting Fungus, Polyporus brumalis, on Specific Medium, including Inorganic Magnesium Source

  • Lee, Su-Yeon;Ryu, Sun-Hwa;Choi, In-Gyu;Kim, Myungkil
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.2
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    • pp.253-263
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    • 2016
  • Fungi, such as the wood-rotting Polyporus brumalis, are excellent sources of pharmaceutically interesting natural products such as sesquiterpenoids. In this study, we investigated the biosynthesis of P. brumalis sesquiterpenoids on modified medium. Ten additional species of white rot fungi were inoculated in medium containing nutrients such as $C_6H_{12}O_6$, $C_4H_{12}N_2O_6$, $KH_2PO_4$, $MgSO_4$, and $CaCl_2$ at $28^{\circ}C$ for 25 days. After 10 days of incubation, eudesmane-type sesquiterpenes, ${\beta}$-eudesmane and ${\beta}$-eudesmol, were only synthesized during the growth phase of P. brumalis. Experiments excluding one nutrient at a time were conducted to determine the effects of inorganic nutrients on sesquiterpene biosynthesis. In conclusion, GC-MS analysis showed that biosynthesis of sesquiterpenes was differentially regulated by inorganic nutrients such as $MgSO_4$, $C_4H_{12}N_2O_6$, and $KH_2PO_4$. We found $MgSO_4$ supplementation to be vital for eudesmane-type sesquiterpene biosynthesis in P. brumalis; nitrogen ($C_4H_{12}N_2O_6$) and phosphate ($KH_2PO_4$) inhibited the synthesis of P. brumalis metabolites. Magnesium is a known cofactor of sesquiterpene synthase, which promotes ${\beta}$-eudesmol synthesis. To mechanistically understand eudesmane-type sesquiterpene biosynthesis in P. brumalis, further research into the genes regulating the dynamics of such biosynthesis is warranted.

Engineering Human-like Sialylation in CHO Cells Producing hCTLA4-Ig by Overexpressing α2,6-Sialyltransferase (α2,6-Sialyltransferase 과발현을 통한 인간형 시알산 부가 hCTLA4-Ig 생산 CHO 세포주 제작)

  • Lim, Jin-Hyuk;Cha, Hyun-Myoung;Park, Heajin;Kim, Ha Hyung;Kim, Dong-Il
    • KSBB Journal
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    • v.32 no.3
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    • pp.193-198
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    • 2017
  • Sialylation is important in producing therapeutic proteins such as antibody, cytokine and fusion protein. Thus, enhancement of sialylation is usually performed in CHO cell cultures. ${\alpha}2,6$-Sialyltransferase (ST), which plays a key role in the attachment of ${\alpha}2,6-sialic$ acid, is present in human cells but not in Chinese hamster ovary (CHO) cells. Overexpression of ${\alpha}2,6-ST$ can be used for enhancing the degree of sialylation and achieving human-like glycosylation. In this study, we constructed CHO cells producing human cytotoxic T-lymphocyte antigen4-immunoglobulin (hCTLA4-Ig) as well as ${\alpha}2,6-ST$. Transfected CHO cells were selected using G418 and stable cell line was established. Profiles of viable cell density and hCTLA4-Ig titer in an overexpressed cell line were similar to those of a wild-type cell line. It was confirmed that the total amount of sialic acid was increased and ${\alpha}2,6-sialic$ acid was attached to the terminal residues of N-glycan of hCTLA4-Ig by ESI-LC-MS. Compared to 100% of ${\alpha}2,3-sialic$ acid in wild type cells, 70.9% of total sialylated N-glycans were composed of ${\alpha}2,6-sialic$ acid in transfected cells. In conclusion, overexpression of ${\alpha}2,6-ST$ in CHO cells led to the increase of both the amount of total sialylated N-glycan and the content of ${\alpha}2,6-sialic$ acid, which is more resemble to human-like structure of glycosylation.

CCNA1 Promoter Methylation: a Potential Marker for Grading Papanicolaou Smear Cervical Squamous Intraepithelial Lesions

  • Chujan, Suthipong;Kitkumthorn, Nakarin;Siriangkul, Sumalee;Mutirangura, Apiwat
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7971-7975
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    • 2014
  • Background: From our previous study, we established that cyclin A1 (CCNA1) promoter methylation is strongly correlated with multistep progression of HPV-associated cervical cancer, suggesting potential use as a diagnostic maker of disease. Objectives: The purpose of the present study was to assess the prevalence of CCNA1 promoter methylation in residual cervical cells isolated from liquid-based cytology that underwent hrHPV DNA screening for cervical cancer, and then to evaluate this marker for diagnostic accuracy using parameters like sensitivity, specificity, predictive values and likelihood ratio. Methods: In this retrospective study, histopathology was used as the gold standard method with specimens separated into the following groups: negative (n=31), low-grade squamous intraepithelial lesions (LSIL, n=34) and high-grade squamous intraepithelial lesions or worse (HSIL+, n=32). The hrHPV was detected by Hybrid Capture 2 (HC2) and CCNA1 promoter methylation was examined by CCNA1 duplex methylation specific PCR. Results: The results showed the frequencies of CCNA1 promoter methylation were 0%, 5.88% and 83.33%, while the percentages of hrHPV were 66.67%, 82.35% and 100% in the negative, LSIL and HSIL+ groups, respectively. Although hrHPV infection showed high frequency in all three groups, it could not differentiate between the different groups and grades of precancerous lesions. In contrast, CCNA1 promoter methylation clearly distinguished between negative/LSIL and HSIL+, with high levels of all statistic parameters. Conclusion: CCNA1 promoter methylation is a potential marker for distinguishing between histologic negative/LSIL and HSIL+using cervical cytology samples.