• Title/Summary/Keyword: Biological Synthesis

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Validation of a HPLC MS/MS Method for Determination of Doxorubicin in Mouse Serum and its Small Tissues (마우스 혈장과 조직에서의 doxorubicin 측정 HPLC-MS/MS 방법)

  • Park, Jung-Sun;Kim, Hye-Kyung;Lee, Hye-Won;Lee, Mi-Hyun;Kim, Hyun-Gi;Chae, Soo-Wan;Chae, Han-Jung
    • Korean Journal of Clinical Pharmacy
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    • v.16 no.1
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    • pp.23-27
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    • 2006
  • Doxorubicin (DXR) is a type of anti-cancer drug called an 'anthracycline glycoside', It works by impairing DNA synthesis, a crucial feature of cell division, and thus is able to target rapidly dividing cells. Doxorubicin is a very serious anti-cancer medication with definite potential to do great harm as well as great good. A liquid chromatography-tandem mass spectroscopy (LC-MS/MS) method was developed to identify and quantify DXR in small-volume biological samples. After the addition of internal standard (IS, $5{\mu}L\;of\;1{\mu}M/ml$ daunorubicin methanol solution) into the serum sample, the drug and IS were extracted by methanol. Following vortex for a 1min and centrifugation at 15,000g for 10 min the organic phase was transferred and evaporated under a vacuum. The residue was reconstituted with $350{\mu}L$ of mobile phase and $10{\mu}L$ was injected into C18 column with mobile phase composed of 0.05M ammonium acetate (0.1 M acetic acid adjusted to pH 3.5) and acetonitrile (40:60, v/v). The flow rate was kept constant at $350{\mu}L/min$. The ions were quantified in the multiple reaction mode (MRM), using positive ions, on a triple quadrupole mass spectrometer. The lower limits of quantification for Doxorubicin in plasma and small tissues were approximately 0.5 ng/mL and 0.5 ng/mL respectively. Intra- and inter-assay accuracy (% of nominal concentration) and precision (% CV) for all analytes were within 15%, respectively.

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The Studies on synthesis of $SnO_2$ doped $In_2O_3$ (ITO: Indium Tin Oxide) powder by spray pyrolysis (분무열분해법(Spray Pyrolysis)에 의한 주석산화물이 도핑된 $In_2O_3$(ITO: Indium Tin Oxide)의 분말 제조에 대한 연구)

  • Kim, Sang Hern
    • Journal of the Korean Applied Science and Technology
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    • v.31 no.4
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    • pp.694-702
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    • 2014
  • The micron-sized ITO(indium tin oxide) particles were prepared by spray pyrolysis from aqueous precursor solutions for indium, and tin and organic additives solution. Organic additives solution with citric acid(CA) and ethylene glycol(EG) were added to aqueous precursor solution for Indium and Tin. The obtained ITO particles prepared by spray pyrolysis from the aqueous solution without organic additives solution had spherical and filled morphologies whereas the obtained ITO particles with organic additives solution had more hollow and porous morphologies with increasing mole of organic additives. The micron-sized ITO particle with organic additives was changed fully to nano-sized ITO particle whereas the micron-sized ITO particle without organic additives was not changed fully to nano-sized ITO particle after post-treatment at $700^{\circ}C$ for 2 hours and wet-ball milling for 24 hours. The size of primary ITO particle by Debye-Scherrer formula and surface resistance of ITO pellet were measured.

Non-traditional Straws: Alternate Feedstuffs for Ruminants

  • Kaushal, S.;Wadhwa, M.;Bakshi, M.P.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.12
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    • pp.1722-1727
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    • 2006
  • The nutritive value of 4 straws, obtained after thrashing of seeds from fodder crops, was assessed as complete feed for ruminants. Sixteen male Murrah buffaloes (liveweight 365.8${\pm}$19.5 kg), were divided into 4 equal groups and offered ad lib. straw of either Trifolium resupinatum, Trifolium alexandrium, Medicago sativa or Lolium perenne, supplemented with minerals and vitamin A, for 40 days in a completely randomized design. Simultaneously, each straw was offered to 3 rumen fistulated male buffaloes in order to assess the biochemical changes in the rumen. Compared to other straws M. sativa straw had higher (p<0.05) organic matter (OM), crude protein (CP), acid-detergent fiber (ADF) and cellulose content. L .perenne had the highest (p<0.05) hemicellulose and lowest (p<0.05) CP and acid-detergent lignin (ADL) content. T. resupinatum had the lowest concentration of cell wall constituents (CWC). The digestibility of nutrients of T. resupinatum and L. perenne straw was similar, but higher (p<0.05) than that of other straws. M.sativa straw showed highest (p<0.05) digestibility of CP. The highest OM digestibility of T. resupinatum and CP digestibility of M. sativa were responsible for highest (p<0.05) total volatile fatty acids and trichloroacetic acid precipitable nitrogen in the strained rumen liquor. The digestible crude protein (DCP) was highest (p<0.05) in M. sativa followed by that in T. alexandrium. The total purine derivatives excreted in urine varied from 0.22-0.32 mmol/kg $W^{.75}/d$. The efficiency of microbial protein synthesis indicated that OM of straws of M. sativa and that of T. alexandrium was used more (p<0.05) efficiently. The microbial protein synthesized was highest in T. resupinatum, but statistically similar to other groups. The values for N-retention and apparent biological value were highest for L. perenne, though comparable with that of M. sativa and T. alexandrium. The available metabolizable energy (ME) was highest (p<0.05) in T. resupinatum followed by that in L. perenne and lowest in M. sativa. It was concluded that all the straws, supplemented with minerals and vitamin A, could be fed exclusively to adult ruminants with no adverse affect, as animals were able to maintain body weight (372${\pm}$20.1 kg).

The Plasma Level of Insulin-like Growth Factor-I (IGF-I) in Relation to Mammary Circulation and Milk Yield in Two Different Types of Crossbred Holstein Cattle

  • Chaiyabutr, N.;Komolvanich, S.;Thammacharoen, S.;Chanpongsang, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.3
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    • pp.343-348
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    • 2004
  • The objective of the present study was to determine the plasma level of insulin-like growth factor-I (IGF-I) in relation to mammary blood flow and milk yield including biological variables of relevance to milk synthesis in two different types of crossbred Holstein cattle at 3 different stages of lactation. Eight heifers were 87.5% HF and eight 50% HF animals were selected for the experiments. The three stages of lactation tested were: early lactation (30 days postpartum), mid-lactation (120 days postpartum) and late lactation (210 days postpartum). Animals in each group were fed a concentrate and rice straw treated with 5% urea as the source of roughage throughout the experiments. In early lactation, mammary blood flow and milk yield of 87.5% HF animals were significantly higher than those of 50% HF animals. In mid- and late lactation, both mammary blood flow and milk yield showed a proportional decrease from the early lactating period of 87.5% HF animals. The trends for persistency were observed in 50% HF animals as for udder blood flow and milk yield throughout the experimental periods. The plasma glucose level of the 50% HF animals was significantly higher than those of 87.5% HF animals in both early and mid-lactation. The concentrations of arterial plasma free fatty acids ($C_{16}\;to\;C_{18}$) were higher in 50% HF animals as compared with 87.5% HF animals in all periods of study. In early lactation, the concentration of plasma growth hormone (GH) of 87.5% HF animals was higher than those of the 50% HF animals, thereafter the mean level of plasma growth hormone declined in both mid- and late lactation. The concentration of plasma IGF-I of 50% HF animals was significantly higher than those of 87.5% HF animals in all stages of lactation. There were no differences among stages of lactation for the levels of plasma IGF-I, insulin and growth hormone in 50% HF animals. In 87.5% HF animals, the plasma levels of both IGF-I and insulin were lower in early lactating period while it showed an increase during mid- and late lactation. The present results indicated that the regulatory role for the higher mammary blood flow and milk yield during lactation in 87.5% HF are not mediated via the higher level of circulating IGF-I. Differences in mammary blood flow and milk yield between 50% HF and 87.5% HF animals are in part due to a higher concentration of circulating growth hormone. The lower level of circulating growth hormone in 50% HF animals would be regulated by higher levels of IGF-I, free fatty acid and glucose in plasma.

A Convenient Synthesis of N', N'-Disubstituted N-Fluorophenylformamidines by Using Microwave and Their Insecticidal Activities (마이크로웨이브를 이용한 N', N'-Disubstituted N-Fluorophenylformamidine 유도체의 편리한 합성과 살충활성)

  • Lee, Dong-Guk;Chung, Kun-Hoe;Ko, Young-Kwan;Ryu, Jae-Wook;Woo, Jae-Chun;Koo, Dong-Wan;Choi, Yong-Ho;Park, No-Joong;Kim, Jin-Ju;Kim, Tae-Joon
    • The Korean Journal of Pesticide Science
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    • v.13 no.2
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    • pp.117-125
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    • 2009
  • Phenylformamidine derivatives are well known as insecticides for their specific activity against the insects. It has now been established that they show insecticidal activity as agonists on the octopamine receptor which is located in the synapse membrane. The reaction of triethylorthoformate and fluoroanilines gave formimidates (1) in good yields and N',N'-Disubstituted N-fluorophenylformamidine derivatives were synthesized more easily by using microwave. This microwave reaction condition gave products in high yields and faster reaction time than conventional methods. All the compounds were screened for their biological activity agaist harmful insects of plant hoppers, moths, aphids and mites. Synthetic compounds of 2-I-a, 2-I-c, 2-I-d, 2-II-d showed good activity against mites and plant hoppers.

Conjugated Linoleic Acid Induces Apoptosis by Activating AMPK in MCF-7 Breast Cancer Cells (MCF-7 유방암 세포에서 AMPK 활성에 의한 conjugated linoleic acid의 apoptosis 유도에 관한 연구)

  • Lin, Sun-Kyo;Kim, Hyun-Sook;Park, Ock-Jin;Kim, Young-Min
    • Journal of Life Science
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    • v.18 no.12
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    • pp.1679-1685
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    • 2008
  • Conjugated linoleic acid (CLA) is a naturally occurring compound found in dairy and beef products. It has been shown to suppress cancer cells and to induce apoptosis. Practically, there is emerging evidence that CLA can inhibit chemically induced carcinogenesis in various tissues. However, the molecular mechanisms of CLA on human MCF-7 breast cancer cells have not been clearly explained yet. In this report, we investigated the anti-cancer activity of CLA in MCF-7 cells. It was found that CLA could inhibit the growth of the MCF-7 cells and induce apoptosis, through modulating AMP-activated protein kinase (AMPK) and cyclooxygenase-2 (COX-2). AMPK acts as a cellular fuel gauge and responds to decreased cellular energy status by inhibiting ATP-consuming pathways and increasing ATP-synthesis. CLA treatment with variable concentrations and different time of same-dose CLA on MCF-7 cells resulted in a strong activation of AMPK and an inhibition of COX-2 expression. It supports that CLA induces apoptosis in CLA-treated MCF 7 cells. Therefore, the effects of CLA induced COX-2 expression via activating AMPK can provide new possibility into the understanding the molecular mechanisms of anti-cancer component.

Uptake, Assimilation and Translocation of Ammonium or Nitrate in Italian Ryegrass

  • Kim, Tae-Hwan;Lee, Bok-Rye;Jung, Woo-Jin;Kim, Dae-Hyun;Chung, Soon-Ju;Kim, Kil-Yong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.46 no.4
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    • pp.303-308
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    • 2001
  • To investigate the partitioning of newly absorbed N derived from NO$_3$- and NH$_4$$^{+}$, 6 mM $K^{15}$ NO$_3$ or 3 mM ($^{15}$ NH$_4$)$_2$ was fed continuously in Italian ryegrass (Lolium multiflrum L.) for 7 days. Nitrogen metabolites (nitrate, amino acid, soluble- and insoluble protein) were analyzed at the end of $^{15}$ N feeding. Dry weight in shoot, stubble and root was not significantly different between NO$_3$$^{[-10]}$ and NH$_4$$^{+}$ feeding. Total nitrogen content in all three organs was significantly higher in NH$_4$$^{+}$ than NO$_3$$^{[-10]}$ feeding. Sum on N content in reduced N fractions (amino acids + proteins) in shoot, stubble and roots in NH$_4$$^{+}$ feeding increased by 13.3, 12.5 and 35.4 %, respectively, compared to NO$_3$$^{[-10]}$ feeding. The Relative Specific Activity (RSA, percentage of newly absorbed $^{15}$ N relative to total N in a sample) values of amino acids and insoluble proteins were significantly higher in NH$_4$$^{+}$ feeding. Total amount of newly absorbed $^{15}$ N in NO$_3$$^{[-10]}$ and NO$_3$$^{[-10]}$ feeding was 52.3 and 69.5 mg/plant on dry matter basis, respectively. In both NH$_4$$^{+}$ and NO$_3$$^{[-10]}$ grown plants, most of the N was allocated to the shoot, 67.5% in NH$_4$$^{+}$ feeding and 58.8% NO$_3$$^{[-10]}$ feeding, respectively. The $^{15}$ N amount incorporated in the reduced N compounds (amino acids and proteins) in NH$_4$$^{+}$ grown plants significantly increased by 74.8% compared to NO$_3$$^{[-10]}$ grown plants. The increase of the $^{15}$ N amount assimilated to amino acids in NH$_4$$^{+}$ grown plants was remarkably higher in roots as more than 7.25 times compared to NO$_3$$^{[-10]}$ feeding. These results indicated that Italian ryegrass was much efficiently utilized NH$_4$$^{+}$-N for the synthesis of reduced N compounds.reduced N compounds.

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Synthesis of Tungsten Doped Vanadium Dioxide and Its Thermochromic Property Studies (텅스텐이 도핑된 바나듐 산화물의 합성 및 열전이 특성 연구)

  • Hwang, Kyung-Jun;Jo, Cho Won;Yoo, Jung Whan
    • Applied Chemistry for Engineering
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    • v.24 no.1
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    • pp.44-48
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    • 2013
  • In this work, we have prepared tungsten doped vanadium oxide ($W-VO_2$) particles with a low phase transition temperature. $W-VO_2$ particles were synthesized via thermolysis method using vanadyl (IV) sulfate and ammonium bicarbonate as precursors. The structure and thermochromic property of synthesized $W-VO_2$ particles were investigated by FE-SEM, EDS, XRD, XPS, and DSC analysis. The prepared $W-VO_2$ showed a nearly platy morphology, which indicates that the tungsten was successfully doped in the crystal lattices of $VO_2$. $W-VO_2$ nanoparticles with the size of 60 nm exhibited a monoclinic crystal structure and its chemical composition and surface state were also likely to be close to that of $VO_2$. In addition, the phase transition temperature of $W-VO_2$ was $38.5^{\circ}C$, which was approximately $29.2^{\circ}C$ lower than that of pure $VO_2$ ($67.7^{\circ}C$), indicating that the prepared sample had a good reversible thermochromic stability.

A Study on Development of ECS for Severly Handicaped (중증 장애인을 위한 생활환경 제어장치개발에 관한 연구)

  • 임동철;이행세;홍석교;이일영
    • Journal of Biomedical Engineering Research
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    • v.24 no.5
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    • pp.427-434
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    • 2003
  • In this paper, we present a speech-based Environmental Control System(ECS) and its application. In the concrete, an ECS using the speech recognition and an portable wheelchair lift control system with the speech synthesis are developed through the simulation and the embodiment. The developed system apply to quadriplegic man and we evaluate the result of physical effect and of mental effect. Speech recognition system is constructed by real time modules using HMM model. For the clinical application of the device, we investigate the result applied to 54-years old quadriplegic man during a week through the questionnaires of Beck Depression Inventory and of Activity Pattern Indicator. Also the motor drive control system of potable wheelchair lift is implemented and the mechanical durability is tested by structural analysis. Speech recognition rate results in over 95% through the experiment. The result of the questionnaires shows higher satisfaction and lower nursing loads. In addition, the depression tendency of the subject were decreased. The potable wheelchair lift shows good fatigue life-cycle as the material supporting the upper wheelchair and shows the centroid mobility of safety. In this paper we present an example of ECS which consists of real-time speech recognition system and potable wheelchair lift. Also the experiments shows needs of the ECS for korean environments. This study will be the base of a commercial use.

Biodegradation of Recalcitrant Chlorinated Aromatic Compounds via Microbial Dechlorination (미생물의 탈염소화 작용에 의한 난분해성 염화방향족 오염물질의 분해)

  • 채종찬;김치경
    • Korean Journal of Environmental Biology
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    • v.17 no.2
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    • pp.129-138
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    • 1999
  • Chlorinated aromatic compounds are one of the largest groups of environmental pollutants as a result of world-wide distribution by using them as herbicides, insecticides, fungicides, solvents, hydraulic and heat transfer fluids, plasticizers, and intermediates for chemical synthesis. Because of their toxicity, persistence, and bioaccumulation, the compounds contaminated ubiquitously in the biosphere has attracted public concerns in terms of serious influences to wild lives and a human being, such as carcinogenicity, mutagenicity, and disturbance in endocrine systems. The biological recalcitrance of the compounds is caused by the number, type, and position of the chlorine substituents as well as by their aromatic structures. In general, the carbon-halogen bonds increase the recalcitrance by increasing electronegativity of the substituent, so that the dechlorination of the compounds is focused as an important mechanism for biodegradation of chlorinated aromatics, along with the cleavage of aromatic rings. The removal of the chlorine substituents has been known as a key step for degradation of chlorinated aromatic compounds under aerobic condition. This can occur as an initial step via oxygenolytic, reductive, and hydrolytic mechanisms. The studies on the biochemistry and genetics about microbial dechlorination give us the potential informations for microbial degradation of xenobiotics contaminated in natural microcosms. Such investigations might provide biotechnological approaches to solve the environmental contamination, such as designing effective bioremediation systems using genetically engineered microorganisms.

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