• Title/Summary/Keyword: fragmentation reaction

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Protective effects Acanthopanax senticosus extracts on ethanol-induced apoptosis in TM3 mouse Leydig cells (오가피전탕액(五加皮煎湯液)이 에탄올에 의해 유발되는 TM3 mouse Leydig 세포주의 apoptosis에 미치는 영향)

  • Kim Jong-Chul;Kim Hee-Taek;Kim Ho-Hyun;Kim Ee-Hwa
    • Korean Journal of Acupuncture
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    • v.20 no.1
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    • pp.57-64
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    • 2003
  • 목적: 오가피가 mouse testis에서 유래된 Leydig 세포주에서 에탄올에 의해 유발된 아폽토시스에 미치는 영향을 조사하였다. 방법: TM3 세포주에서의 아폽토시스 변화를 관찰하기 위해서 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, 4,6-diamidino-2-phenylindole (DAPI), DNA fragmentation assay, 및 reverse transcription-polymerase chain reaction (RT-PCR) 방법을 이용하였다. 결과: MTT assay를 이용하여 분석한 결과 농도에 따른 세포독성의 효과가 에탄올 투여부터 관찰되었다. 또한 오가피로 전처치하고 에탄올을 처치하였을 때 세포독성이 크게 감소되었다. DAPI staining에서 오가피 투여군은 에탄올 투여군에 비해서 fragmentation이 억제되었다. RT-PCR의 분석에 의하여 caspase-3 mRNA 발현이 오가피 투여군은 알코올 투여군보다 유의성있게 억제됨을 보여주었다. 결론: TM3 Leydig 세포주에서 에탄올에 의해 유발된 아폽토시스는 전형적인 세포사멸 형태를 나타내었다. 반면에 오가피 투여군은 에탄올에 의해서 유발된 아폽토시스에서 세포보호 효과가 있음이 확인되었다.

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Synergistic Effect of Glucoamylase and $\alpha$-Amylase in Enzymatic Hydrolysis of Raw Corn Starch in an Agitated Bead Reaction System (분쇄마찰매체 효소반응계에서 생전분 효소당화를 위한 Glucoamylase와 Alpha-Amylase의 보완작용)

  • 이용현;박동찬
    • Microbiology and Biotechnology Letters
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    • v.18 no.4
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    • pp.352-359
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    • 1990
  • The synergistic effect of glucoamylase and a -amylase on the hydrolysis of raw corn starch in an agitated bead reaction system was studied by investigating the changes of sugar profiles, the granular structure, particle size distribution, and X-ray diffraction pattern of residual raw corn starch. The enzymatic hydrolysis of raw corn starch was greatly enhanced by synergistic effect of glucoamylase and $\alpha$ -amylase. Even though the sugar profiles were mainly determined by the mixing ratio of glucoamylase and $\alpha$-amylase; raw starch was mainly converted to glucose directly without accumulation of any significant amount of oligosaccharides. The cavity formation and fragmentation phenomena of raw corn starch granule subjected to enzyme reaction were analyzed by means of SEM and the particle size distribution. The X-ray diffraction pattern of raw starch was not changed at the initial stage of reaction but slightly changed at the late stage of hydrolysis, which may be caused by the preferential degradation of amorphous region by enzymatic reaction, not by the destruction of microcrystalline structure of raw corn starch.

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Substituent Effect on Fragmentations and Ion-Molecule Reactions of Ionized Alkyn Alcohols

  • Choi, Sung-Seen;So, Hun-Young;Kim, Beom-Tae
    • Bulletin of the Korean Chemical Society
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    • v.26 no.4
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    • pp.609-613
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    • 2005
  • The fragmentation patterns and ion-molecule reactions of two alkyn alcohols, 2-propyn-1-ol (HC≡$CCH_2$OH) and 2-methyl-3-butyn-2-ol (HC≡CC($CH_3)_2$OH), were investigated using Fourier transform mass spectrometry (FTMS). The most abundant fragment ions formed from the molecular ions were [M-H]$^+$ for 2-propyn-1-ol and [M-$CH_3]^+$ for 2-methyl-3-butyn-2-ol. The dehydrated ion, [M-$H_2O]^+$ was formed only from 2-propyn-1-ol in which $\alpha$ -hydrogen atoms were available for $\alpha,\;\alpha$ -elimination reaction. The protonated molecules were dissociated into [M+H-$H_2O]^+$ and [M+H-$C_2H_2]^+$ through dehydration and deacetylenylation processes. The formations of [M+H-$H_2O]^+$ and [M+H-$C_2H_2]^+$ from 2-methyl-3-butyn-2-ol were more favorable than those from 2-propyn-1-ol due to stabilization by two methyl groups at $\alpha$ -carbon. Ion-neutral complexes formed at long ion trapping time gave dehydrated and/or deacetylenylated ion products by further dissociation.

Glycation of Copper, Zinc-Superoxide Dismutase and its Effect on the Thiol-Metal Catalyzed Oxidation Mediated DNA Damage

  • Park, Jeen-Woo;Lee, Soo-Min
    • BMB Reports
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    • v.28 no.3
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    • pp.249-253
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    • 1995
  • The nonenzymatic glycation of copper, zinc-superoxide dismutase (Cu,Zn-SOD) led to inactivation and fragmentation of the enzyme. The glycated Cu,zn-SOD was isolated by boronate affinity chromatography. The formation of 8-hydroxy-2'-deoxyguanosine (8-OH-dG) in calf thymus DNA and the generation of strand breaks in pBhiescript plasmid DNA by a metal-catalyzed oxidation (MCO) system composed of $Fe^{3+}$, $O_2$, and glutathione (GSH) as an electron donor was enhanced more effectively by the glycated CU,Zn-SOD than by the nonglycated enzyme. The capacity of glycated Cu,Zn-SOD to enhance damage to DNA was inhibited by diethylenetriaminepentaacetic acid (DETAPAC), azide, mannitol, and catalase. These results indicated that incubation of glycated CU,Zn-SOD with GSH-MCO may result in a release of $Cu^{2+}$ from the enzyme. The released $Cu^{2+}$ then likely participated in a Fenton-type reaction to produce hydroxyl radicals, which may cause the enhancement of DNA damage.

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Peroxynitrite Scavenging Mechanism of Alaternin and Nor-rubrofusarin glucose from Cassia tora

  • Park, Tae-Hyun;Jung, Hyun-Ah;Choi, Jae-Sue;Chung, Hae-Young
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.318.3-319
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    • 2002
  • Peroxynitrite(ONOO-), formed from the reaction of superoxide(O2-) and nitric oxide(NO), is a potent oxidant that contributes to oxidation of various cellular constituents including lipids. amino acids, sulphydryls and nucleotides. It can cause cellular injury such as DNA fragmentation and apoptotic cell death. Also. the toxicity of ONOO- has been reported to be involved in inflammatory and nurodegenerative diseases such as Alzheimer's disease, Parkinson's disease. and atherosclerosis. (omitted)

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Profile and Dose Distribution for Therapeutic Heavy Ion Beams

  • Sasaki, Hitomi;Komori, Masataka;Kohno, Toshiyuki;Kanai, Tatsuaki;Hirai, Masaaki;Urakabe, Eriko;Nishio, Teiji
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2002.09a
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    • pp.211-213
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    • 2002
  • The purpose of this work is acquiring some parameters of therapeutic heavy ion beams after penetrating a thick target. The experiments were performed using a pencil-like $\^$12/C beam of about 3 mm in diameter from NIRS-HIMAC, and the data were taken at several points of the target thickness for $\^$12/C beam of 290 MeV/u and 400 MeV/u. By the simultaneous measurements using some detectors, the atomic number of each fragment particle was identified, and the beam profile, the dose distribution and the LET spectrum for each element were derived.

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A Development of a Transient Hydrogen Generation Model for Metal-Water Interactions

  • Lee, Jin-Yong;Park, Goon-Cherl;Lee, Byung-Chul
    • Nuclear Engineering and Technology
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    • v.32 no.6
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    • pp.549-558
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    • 2000
  • A transient model for hydrogen generation in molten metal-water interactions was developed with separate models for two stages of coarse mixing and stratification. The model selves the mechanistic equations (heat and mass transfer correlation, heat conduction equation and the concentration diffusion equation) of each stage with non-zero boundary conditions. Using this model, numerical simulations were performed for single droplet experiments in the Argonne National Laboratory tests and for FITS tests that simulated dynamic fragmentation and stratification. The calculation results of hydrogen generation showed better agreement to the experiment data than those of previous works. It was found from the analyses that the steam concentration to be reached at the reaction front might be the main constraint to the extent of the metal droplet oxidized. Also, the hydrogen generation rate in the coarse mixing stage was the higher than that in the stratification stage. The particle size was the most important factor in the coarse mixing stage to predict the amount of hydrogen generation.

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Characterization of Ion Fragmentations of Fatty Acids

  • 최성신
    • Bulletin of the Korean Chemical Society
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    • v.18 no.6
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    • pp.573-578
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    • 1997
  • Ion fragmentations of fatty acids such as stearic acid, palmitic acid, myristic acid, and lauric acid were studied using mass spectrometry and semiempirical calculations. The mass spectra of fatty acids showed the distributions of CH₃(CH₂)$_n^+$ and $[(CH_2)_nCO_2H]^+$ fragment ions. The relative ion abundance distributions of $[(CH_2)_nCO_2H]^+$ showed the local maxima at n=6, 10, and 14. The local maximum phenomena were also found in the mass spectra of methyl stearate but not in those of normal alcohols. These local maxima could be explained not by heats of reaction for fragmentation but by the cyclic structures of the molecular ions. The AM1 semiempirical calculations for fatty acids clearly show that the linear structures are more favorable than the cyclic ones for neutral molecules while the cyclic structures are more favorable than the linear ones for ionic molecules. The distances between carboxyl group and methylene of the cylic structures of ionized fatty acids were calculated. The methylene carbons with n=6, 10, and 14 were closer to the carboxyl group than adjacent ones.

Induction of ER Stress-Mediated Apoptosis by ${\alpha}$-Lipoic Acid in A549 Cell Lines

  • Kim, Jong-In;Cho, Sung-Rae;Lee, Chang-Min;Park, Eok-Sung;Kim, Ki-Nyun;Kim, Hyung-Chul;Lee, Hae-Young
    • Journal of Chest Surgery
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    • v.45 no.1
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    • pp.1-10
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    • 2012
  • Background: ${\alpha}$-Lipoic acid (${\alpha}$-LA) has been studied as an anticancer agent as well as a therapeutic agent for diabetes and obesity. We performed this study to evaluate the anticancer effects and mechanisms of ${\alpha}$-LA in a lung cancer cell line, A549. Materials and Methods: ${\alpha}$-LA-induced apoptosis of A549 cells was detected by fluorescence-activated cell sorting analysis and a DNA fragmentation assay. Expression of apoptosis-related genes was analyzed by western blot and reverse transcription.polymerase chain reaction analyses. Results: ${\alpha}$-LA induced apoptosis and DNA fragmentation in A549 cells in a dose- and time-dependent manner. ${\alpha}$-LA increased caspase activity and the degradation of poly (ADP-ribose) polymerase. It induced expression of endoplasmic reticulum (ER) stress-related genes, such as glucose-regulated protein 78, C/EBP-homologous protein, and the short form of X-box binding protein-1, and decreased expression of the anti-apoptotic protein, X-linked inhibitor of apoptosis protein. Reactive oxygen species (ROS) production was induced by ${\alpha}$-LA, and the antioxidant N-acetyl-L-cysteine decreased the ${\alpha}$-LA-induced increase in expression of apoptosis and ER stress-related proteins. Conclusion: ${\alpha}$-LA induced ER stress-mediated apoptosis in A549 cells via ROS. ${\alpha}$-LA may therefore be clinically useful for treating lung cancer.

The Effects of Endocrine Disruptors on the Development of Mouse Preimplantation Embryos and the Regulation of Apoptotic Gene Repression (내분비계 장애물질이 착상전 생쥐 배아의 발생 및 Apoptosis 조절 유전자 발현에 미치는 영향)

  • 정경남;유정민;유성진;김주란;정철희;김현찬;강성구
    • Development and Reproduction
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    • v.6 no.1
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    • pp.25-30
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    • 2002
  • Endocrine disruptors have been reported to adversely affect reproduction and embryonic development in wild animals. One of the major abnormalities observed during early embryonic development is cellular fragmentation. In this study, we exposed mouse preimplantation embryos to PCB, BPA and DDT in vivo or in vitro. Embryos exposed to endocrine disrupter showed a variety of morphological abnormalities such as fragmentation, irregular blastomeres and cracked empty zonae pellucidae. To investigate the levels of gene expression related which genes contribute to apoptosis in preimplantation mouse embryos, we carried out the reverse transcription polymerase chain reaction to assess mRNA levels far apoptotic gene. Bcl-2, bad and bax expression levels were compared between control group and endocrine disrupter treated group. Expression level of bcl-2 gene tended to be lower in the treated group than control while expression levels of bad and bax genes were higher in the treated group. Results of this study may provide a useful tool for rapidly screening developmental toxicants in preimplantation embryos exposed to endocrine disruptors in vivo or in vitro.

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