• Title/Summary/Keyword: Chain Reaction

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The Selective Synthesis of ${alpha}$-Sulfo Long Chain Fatty Acid Monoglyceride ((${alpha}$-술폰 고급 지방산 모노글리세라이드의 선택적 합성)

  • Yun, Y.K.;Jeoung, H.G.;Park, S.S.;Kim, T.Y.;Nam, K.D.
    • Journal of the Korean Applied Science and Technology
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    • v.10 no.1
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    • pp.31-38
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    • 1993
  • Anionic polyolic surfactants, ${alpha}-sulfo$ fatty acids that straight long chain alkyl group has from 12 to 18 hydrocarbon numbers, was synthesized with sulfur trioxide-dioxane complex to good yields. New sodium ${alpha}-sulfo$ long chain fatty acid monoglyceride were obtained by reaction that the ketalificaticn and esterification of glycerol, acetone and ${alpha}-sulfo$ long chain fatty acid and hydrolysis respectively. These reaction products separated by column chromatography and their $R_{f}$ values($R_{f}{\times}100$) were 19, 21, 24 and 26 respectively. These compounds were identified by infrared spectroscopy and $^{1}H$ NMR spectroscopy.

Polymerization of Anisole Derivatives Containing Allyl or Chloromethyl Group Through Aromatic Electrophilic Substitution Reaction

  • 장지영;박필정;한만정
    • Bulletin of the Korean Chemical Society
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    • v.18 no.12
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    • pp.1288-1291
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    • 1997
  • 4-Allylanisole was polymerized with AlCl3 as a catalyst. The polymerization was carried out in nitroethane at various temperatures with changing the ratio of the initiator to the monomer concentration. The weight averge molecular weights measured by gel permeation chromatography in chloroform with polystyrene standards were between 1,500 and 4,700. 1H NMR spectroscopy showed that the polymerization proceeded through a stepwise aromatic electrophilic substitution reaction along with a minor chain-reaction, resulting in a branched polymer. 4-Chloromethylanisole was also polymerized with AlCl3 in nitroethane through an aromatic electrophilic substitution reaction to give a high molecular weight polymer (Mw=88,000).

Detection and Epidemiological Survey of Canine Parvoviral Enteritis by Polymerase Chain Reaction (Polymerase Chain Reaction을 이용한 Canine Parvovirus성장염의 진단과 역학조사)

  • Kim, Doo;Jang, Wook
    • Journal of Veterinary Clinics
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    • v.14 no.2
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    • pp.177-184
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    • 1997
  • Canine parvovirus(CPV) is a very highly contagious virus causing hemorrhagic enteritis and myocarditis mainly in young dogs. The diseases were first recognized in 1978, and then spread throughout the world by 1980. The main source of the infection seems to be the feces of infected dogs, at the same time feces are suitable materials for detection of virus in the enteric form exactly for the same reasons. Recently, a new technique of in vitro DNA amplification, Known as the polymerase chain reaction (PCR), has been widely applied to clinical viral diagnosis because of its sensitivity, specificity and rapidity. In this research, we attemped to set up the PCR for the detection of CPV in fecal samples and conformed the canine parvpviral enteritis by PCR. To increase the sensitivity and specificity of a PCR, the nested PCR (two-step PCR) was performed. We also surveyed the contamination status of CPV in the research using fecal specimen was highly sensitive and specific. Of the 100 fecal specimens suspected canine parvoviral enteritis, 45 fecal specimens were positive in HA test, 64 fecal specimens were positive in the first PCR, and 87 fecal specimens were positive in the second PCR. CPV contamination status of animal clinics and breeding centers was serious, wo hygienic management of environment in which dogs are reared is required. The nested PCR described here seems to be a rapid, sensitive and specific for the detection of canine parvovirus.

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Single-tube nested reverse transcription-polymerase chain reaction for simultaneous detection of genotyping of porcine reproductive and respiratory syndrome virus without DNA carryover contamination (DNA 교차오염 방지기능이 있는 single-tube nested reverse transcription-polymerase chain reaction을 이용한 돼지생식기호흡기증후군바이러스 유전형 감별진단)

  • Jeong, Pil-Soo;Park, Su-Jin;Kim, Eun-Mi;Park, Ji-Young;Park, Yu-Ri;Kang, Dae-Young;Cha, Hyun-Ouk;Lee, Kyoung-Ki;Kim, Seong-Hee;Park, Choi-Kyu
    • Korean Journal of Veterinary Service
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    • v.39 no.2
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    • pp.107-116
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    • 2016
  • In the study, we developed and evaluated a uracil N-glycosylase (UNG)-supplemented single-tube nested reverse transcription-polymerase chain reaction (UsnRT-PCR) assay that can carried out first-round RT-PCR and second-round nested PCR in a reaction tube without reaction tube opening and can simultaneously detect EU- and NA-PRRSV. The UsnRT-PCR confirmed to have a preventing ability of mis-amplification by contamination of pre-amplified PRRSV DNA from previous UsnRT-PCR. Primer specificities were evaluated with RNAs extracted from 8 viral strains and our results revealed that the primers had a high specificity for both genotypes of PRRSV. The sensitivity of the UsnRT-PCR was 0.1 $TCID_{50}$/0.1 mL for EU- or NA-PRRSV, respectively, which is comparable to that of previously reported real time RT-PCR (RRT-PCR). Clinical evaluation on 110 field samples (60 sera and 50 lung tissues) by the UsnRT-PCR and the RRT-PCR showed that detection rates of the UsnRT-PCR was 70% (77/110), and was relatively higher than that of the RRT-PCR (69.1%, 76/110). The percent positive or negative agreement of the UsnRT-PCR compared to RRT-PCR was 96.1% (73/76) or 90.9% (30/33), showing that the test results of both assays may be different for some clinical samples. Therefore, it is recommend that diagnostic laboratory workers use the two diagnostic assays for the correct diagnosis for the relevant samples in the swine disease diagnostic laboratories. In conclusion, the UsnRT-PCR assay can be applied for the rapid, and reliable diagnosis of PRRSV without concerns about preamplified DNA carryover contamination that can occurred in PCR process in the swine disease diagnostic laboratories.