• Title/Summary/Keyword: $S_N2-S_N2'$ Reaction

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Clinical efficacy and safety of lamotrigine monotherapy in newly diagnosed pediatric patients with epilepsy (간질 환아에서 Lamotrigine 초기 단독 요법의 효능 및 안정성에 대한 연구)

  • Han, Ji-Hye;Oh, Jung-Eun;Kim, Sun-Jun
    • Clinical and Experimental Pediatrics
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    • v.53 no.4
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    • pp.565-570
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    • 2010
  • Purpose : To verify the efficacy and safety of lamotrigine (LTG) monotherapy in newly diagnosed children with epilepsy. Methods : We prospectively enrolled 148 children who had undergone LTG monotherapy at our institution between September 2002 and June 2009. Twenty-nine patients were excluded: 19 due to incomplete data and 10 were lost to follow up. The data of the remaining 119 patients was analyzed. Results : We enrolled 119 pediatric epilepsy patients (aged 2.8-19.3 years; 66 males and 53 females) in this study. Out of 119 patients, 29 (25.2%) had generalized epilepsy and 90 (74.8%) had partial epilepsy. The responses of seizure reduction were as follows: Seizure freedom (no seizure attack for at least 6 months) in 87/111 (78.4%, n=111) patients; partial response (reduced seizure frequency compared to baseline) in 13 (11.7%) patients; and persistent seizure in 11 (9.9%) patients. The seizure freedom rate was in 81.6% in patients with partial seizure (75.9% for complex partial seizure and 90.9% for benign rolandic epilepsy) and 44.8% in patients with generalized epilepsy (30.0% for absence seizure, 35.7% for juvenile myoclonic epilepsy patients, and 100.0% for idiopathic generalized epilepsy patients). Adverse reactions were reported in 17 (14.3%) patients, and 8 patients (6.7%) discontinued LTG because of rash and tic. No patient experienced severe adverse reaction such as Stevens-Johnson syndrome. Conclusion : LTG showed excellent therapeutic response and had few significant adverse effects. Our findings report may contribute in promoting the use of LTG monotherapy in epileptic children.

Evaluation of Denitrification Reactivity by the Supported Nanoscale Zero-Valent Iron Prepared in Ethanol-Water Solution (이중용매에서 제조된 나노영가철을 이용한 질산성질소의 환원반응성 평가)

  • Park, Heesu;Park, Yong-Min;Oh, Soo-Kyeong;Lee, Seong-Jae;Choi, Yong-Su;Lee, Sang-Hyup
    • Korean Chemical Engineering Research
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    • v.46 no.5
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    • pp.1008-1012
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    • 2008
  • Nanoscale zero-valent iron(nZVI) is famous for its high reactivity originated from its high surface area and it has received considerable attentions as one of the latest innovative technologies for treating contaminated groundwater. Due to its fine powdery form, nZVI has limited filed applications. The efforts to overcome this shortcoming by immobilizing nZVI on a supporting material have been made. This study investigated the differences of resin-supported nZVI's characteristics by changing the preparation methods and evaluated its reactivity. The borohydride reduction of an iron salt was proceeded in ethanol/water solvent containing a dispersant and the synthesis was conducted in the presence of ion-exchange resin. The resulting material was compared to that prepared in a conventional way of using de-ionized water by measuring the phyrical and chemical characteristics. BET surface area and Fe content of nZVI-attached resin was increased from $31.63m^2/g$ and 18.19 mg Fe/g to $38.10m^2/g$ and 22.44 mg Fe/g, respectively, by switching the solution medium from water to ethanol/water with a dispersant. The reactivity of each material was tested using nitrate solution without pH control. The pseudo first-order constant of $0.462h^{-1}$ suggested the reactivity of resin-supported nZVI prepared in ethanol/water was increased 61 % compared to that of the conventional type of supported nZVI. The specific reaction rate constant based on surface area was also increased. The results suggest that this new supported nZVI can be used successfully in on-site remediation for contaminated groundwater.

The Use of the Internal Transcribed Spacer Region for Phylogenetic Analysis of the Microsporidian Parasite Enterocytozoon hepatopenaei Infecting Whiteleg Shrimp (Penaeus vannamei) and for the Development of a Nested PCR as Its Diagnostic Tool

  • Ju Hee Lee;Hye Jin Jeon;Sangsu Seo;Chorong Lee;Bumkeun Kim;Dong-Mi Kwak;Man Hee Rhee;Patharapol Piamsomboon;Yani Lestari Nuraini;Chang Uook Je;Seon Young Park;Ji Hyung Kim;Jee Eun Han
    • Journal of Microbiology and Biotechnology
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    • v.34 no.5
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    • pp.1146-1153
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    • 2024
  • The increasing economic losses associated with growth retardation caused by Enterocytozoon hepatopenaei (EHP), a microsporidian parasite infecting penaeid shrimp, require effective monitoring. The internal transcribed spacer (ITS)-1 region, the non-coding region of ribosomal clusters between 18S and 5.8S rRNA genes, is widely used in phylogenetic studies due to its high variability. In this study, the ITS-1 region sequence (~600-bp) of EHP was first identified, and primers for a polymerase chain reaction (PCR) assay targeting that sequence were designed. A newly developed nested-PCR method successfully detected the EHP in various shrimp (Penaeus vannamei and P. monodon) and related samples, including water and feces collected from Indonesia, Thailand, South Korea, India, and Malaysia. The primers did not cross-react with other hosts and pathogens, and this PCR assay is more sensitive than existing PCR detection methods targeting the small subunit ribosomal RNA (SSU rRNA) and spore wall protein (SWP) genes. Phylogenetic analysis based on the ITS-1 sequences indicated that the Indonesian strain was distinct (86.2% nucleotide sequence identity) from other strains collected from Thailand and South Korea, and also showed the internal diversity among Thailand (N = 7, divided into four branches) and South Korean (N = 5, divided into two branches) samples. The results revealed the ability of the ITS-1 region to determine the genetic diversity of EHP from different geographical origins.

Association between Kawasaki disease and acute respiratory viral infections (가와사끼병과 급성 호흡기 바이러스 감염증의 연관성에 관한 연구)

  • Cho, Eun Young;Eun, Byung Wook;Kim, Nam Hee;Lee, Jina;Choi, Eun Hwa;Lee, Hoan Jong;Choi, Jung Yun
    • Clinical and Experimental Pediatrics
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    • v.52 no.11
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    • pp.1241-1248
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    • 2009
  • Purpose:The etiology of Kawasaki disease (KD) is still unknown. Recently, an association between human coronavirus NL63 (HCoV-NL63) and KD was implicated. Hence, we attempted to determine the association between KD and acute respiratory viral infections. Methods:Nasopharyngeal aspirate samples were obtained from 54 patients diagnosed with KD at the Seoul National University (SNU) Children's Hospital and SNU-Bundang Hospital between October 2003 and September 2006. Viral diagnoses of 11 respiratory viruses were made using multiplex reverse transcriptase-polymerase chain reaction (RT-PCR): respiratory syncytial virus (RSV), adenovirus, rhinovirus (RV), parainfluenza viruses (PIVs) 1 and 3, influenza viruses (IFVs) A and B, human metapneumovirus (HMPV), human bocavirus (HBoV), HCoV OC43/229E, and HCoV-NL63. Clinical data were reviewed retrospectively. Results:The median age was 32 months (6 months-10.4 years). Respiratory symptoms were observed in 37 patients (69%). The following respiratory viruses were identified in 12 patients (22%): RV (n=4), PIV-3 (n=2), HBoV (n=2), and adenovirus, RSV, PIV-1, IFV-A, and HCoV-NL63 (n=1). Co-infection with PIV-3 and RV was observed in one patient. Respiratory symptoms were observed in 7 (58.3%) and 30 (71.4%) patients of the virus-positive and virus-negative groups (P>0.05). Response rate to intravenous immunoglobulin administration was 67% (n=8) and 86% (n=36) in the virus- positive and virus-negative groups (P>0.05). Conclusion:Respiratory symptoms were commonly observed in KD patients but the association between respiratory viruses and KD were not found. Large multicenter-based investigations are required to confirm the association between acute respiratory viral infections and KD.

A New Functional Model of Catechol Dioxygenases: Properties and Reactivity of [Fe(BLPA)DBC]$BPh_4$

  • Lim, Ji H.;Lee, Ho J.;이강봉;Jang, Ho G.
    • Bulletin of the Korean Chemical Society
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    • v.18 no.11
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    • pp.1166-1172
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    • 1997
  • [FeⅢ(BLPA)DBC]BPh4, a new functional model for the catechol dioxygenases, has been synthesized, where BLPA is bis((6-methyl-2-pyridyl)methyl)(2-pyridylmethyl)amine and DBC is 3,5-di-tert-butylcatecholate dianion. The BLPA complex has a structural feature that iron center has a six-coordinate geometry with N4O2 donor set. It exhibits EPR signals at g=5.5 and 8.0 which are typical values for the high-spin FeⅢ (S=5/2) complex with axial symmetry. The BLPA complex reacts with O2 within a few hours to afford intradiol cleavage (75%) and extradiol cleavage (15%) products which is very unique result of all [Fe(L)DBC] complexes studied. The iron-catecholate interaction of BLPA complex is significantly stronger, resulting in the enhanced covalency of the metal-catecholate bonds and low energy catecholate to FeⅢ charge transfer bands at 583 and 962 nm in CH3CN. The enhanced covalency is also reflected by the isotropic shifts exhibited by the DBC protons, which indicate increased semiquinone character. The greater semiquinone character in the BLPA complex correlates well with its high reactivity towards O2. Kinetic studies of the reaction of the BLPA complex with 1 atm O2 in CH3OH and CH2Cl2 under pseudo-first order conditions show that the BLPA complex reacts with O2 much slower than the TPA complex, where TPA is tris(2-pyridylmethyl)amine. It is presumably due to the steric effect of the methyl substituent on the pyridine ring. Nevertheless, both the high specificity and the fast kinetics can be rationalized on the basis of its low energy catecholate to FeⅢ charge transfer bands and large isotropic NMR shifts for the BLPA protons. These results provide insight into the nature of the oxygenation mechanism of the catechol dioxygenases.

Leaving-Group Substituent Controls Reactivity and Reaction Mechanism in Aminolysis of Phenyl Y-Substituted-Phenyl Carbonates

  • Kang, Ji-Sun;Song, Yoon-Ju;Um, Ik-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.34 no.7
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    • pp.2023-2028
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    • 2013
  • A kinetic study is reported for the nucleophilic substitution reactions of phenyl Y-substituted-phenyl carbonates (5a-5k) with piperidine in 80 mol % $H_2O$/20 mol % DMSO at $25.0{\pm}0.1^{\circ}C$. The plots of $k_{obsd}$ vs. [piperidine] for the reactions of substrates possessing a strong electron-withdrawing group (EWG) in the leaving group (i.e., 5a-5i) are linear and pass through the origin. In contrast, the plots for the reactions of substrates bearing a weak EWG or no substituent (i.e., 5j or 5k) curve upward, indicating that the electronic nature of the substituent Y in the leaving group governs the reaction mechanism. Thus, it has been suggested that the reactions of 5a-5i proceed through a stepwise mechanism with a zwitterionic tetrahedral intermediate (i.e., $T^{\pm}$) while those of 5j and 5k proceed through a stepwise mechanism with two intermediates (i.e., $T^{\pm}$ and its deprotonated form $T^-$). The slope of the Br${\o}$nsted-type plot for the second-order rate constants (i.e., $k_N$ or $Kk_2$) changes from -0.41 to -1.89 as the leaving-group basicity increases, indicating that a change in the rate-determining step (RDS) occurs. The reactions of 5a-5k with piperidine result in larger $k_1$ values than the corresponding reactions with ethylamine.

Analysis of the Korea Food and Drug Administration Adverse Drug Reaction Reports (식품의약품안전청 약물유해반응 보고자료 분석)

  • Rhew, Ki-Yon;Lee, Suk-Hyang
    • Korean Journal of Clinical Pharmacy
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    • v.21 no.2
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    • pp.138-144
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    • 2011
  • In order to minimize such adverse drug reactions, governments and international organs have been on the watch for them. Also in South Korea, a system has been established in order that adverse drug reactions may be reported to Korea Food and Drug Administration(KFDA). This study is to analyze drugs to cause adverse reactions, the adverse reactions and patients concerned on the authority of the data of Korea FDA, which is expected to be the preliminary data on preventable adverse reactions. This study was conducted on the 74,037 cases of adverse drug reactions reported to Korea FDA between January 2007 and June 2010. Fentanyl, iopromide and tramadol caused adverse reactions with high frequencies. Oseltamivir showed a high frequency between 2009 and 2010 due to the influence of the new influenza A. Also, OTC drugs accounted for approximately 5% of the adverse reactions. In 2009, adverse drug reactions remarkably increased (2,106 cases; 10.1%) in infants and children due to the new influenza-A(H1N1). The patients aged between 31 and 64 accounted for approximately 55% during the given period. There was no significant intergender difference. In relation to regions, the adverse reactions most frequently occurred in the gastrointestinal system and the integumentary system for three and half years. In addition to anticancer drugs and immunosuppressive drugs that are known to cause adverse reactions frequently, not a few of OTC drugs and external preparations caused such reactions. In particular, the drugs containing specific ingredients caused adverse reactions more frequently than others from 2007 until the first half of 2010. It is advisable for prescribers to acquaint themselves with such adverse reactions and to prescribe drugs other than them. They also have need to sensibly cope with adverse drug reactions just in case they have no substitute drugs. In addition, patients also need to be trained to understand possible adverse reactions in order that they can sensibly accommodate them or choose healthcare services. The results of this study are expected to be helpful to minimize adverse drug reactions.

Fabrication of long SmBCO coated conductor on IBAD-MgO template using co-evaporation method (동시증발법을 이용한 SmBCO/IBAD-MgO 박막 장선재 제조)

  • Ha, H.S.;Kim, H.S.;Ko, R.K.;Yoo, K.K.;Yang, J.S.;Kim, H.K.;Jung, S.W.;Lee, J.H.;Lee, N.J.;Kim, T.H.;Song, K.J.;Ha, D.W.;Oh, S.S.;Youm, D.;Park, C.;Yoo, S.I.;Moon, S.H.;Joo, J.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.241-241
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    • 2007
  • We fabricated SmBCO coated conductors(CCs) on IBAD-MgO templates using co-evaporation method. IBAD-MgO templates consist of PLD-LMO/epi-MgO/IBAD-MgO/Ni-alloy and showed good in-plane texture of below FWHM 7 degree. Evaporation rates of Sm, Ba, and Cu were precisely controlled to get the optimum composition ratio after deposition process. To optimize the oxygen partial pressure of reaction region, wide range of the partial pressure was investigated from 1 mTorr to 15 mTorr. By reducing the oxygen partial pressure to 5mTorr, (103)grains in SmBCO layer have been increased. On the other hand, there were only (001)grains in SmBCO layer deposited at 15 mTorr $O_2$. Deposition temperature was also investigated from $600^{\circ}C\;to\;800^{\circ}C$ to make high Ic SmBCO CCs. SmBCO on IBAD MgO template showed that the Ic increased gradually at higher growth temperature to $800^{\circ}C$, which the highest Jc and Ic is $2.6\;MA/cm^2$ and 500 A/cm-w., respectively.

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Synthesis and Characterization of Novel Polythiourethanes (새로운 폴리(티오우레탄)의 합성 및 특성)

  • 김경만;허영태;박인환;이범재
    • Polymer(Korea)
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    • v.27 no.5
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    • pp.470-476
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    • 2003
  • In order to obtain high refractive plastic materials, 1,2 -ethylenedisulfanylbis(2-mercaptomethyl-1-ethanthiol) (ESTT) was newly prepared in good yield by the reaction of 1,2-ethylenedisulfanylbis(2-bromomethyl-1-ethanthiol) (ESTB) with thiourea followed by hydrolysis using an aqueous ammonia solution and characterized by $^1$H-NMR (-SH at 1.7 ppm), $\^$13/C-NMR(-CH$_2$SH at 28.4 ppm) and FT-IR (-SH at 2540 cm$\^$-1/) spectroscopy, etc. Polythiourethanes (PTU) were obtained from the combinations of ESTT with each of 4,4'-methylenebis(phenylisocyanate) (MDI), tolyene 2,4-diisocyanate (TDI), isophorone diisocyanate (IPDI), mxylene diisocyanate (XDI), and 1,6-diisocyanatohexane (HMDI) in the presence of dibutyltin dilaurylate as a catalyst, in a casting mold, and characterized by FT-IR (existence of N=C=O) spectroscopy and elemental analyzer (sulfur content). Accordingly, their thermal, mechanical and optical properties were investigated by using DSC, TGA, hardness tester and refractometer: both the melting point on DSC and crystallinity on X -ray diffraction (XRD) for specimens of PTUs were not observed. PTUs with T$\_$g/s above 110 $^{\circ}C$ showed good hardness (Shore D) in the range of 86 to 89. Thermal stabilities of PTUs obtained by using ESTT and each of diisocyanates containing aromatic rings were especially good. Also, the optical transmittances of amorphous PTUs through UV-visible source in the range of 400 to 600 nm were good. PTUs showed refractive indexes above 1.60, and their refractive indexes gradually increased with increase of sulfur contents.

Anti-inflammation Effect of Cyrtomium fortunei J.Sm. Extracts in Lipopolysaccharides-induced Microglia BV2 Cell (LPS로 자극한 microglia BV2 cell에서 Cyrtomium fortunei J.Sm. 추출물의 항염증 효과)

  • Jiwon Choi;Shintae Kim;Sang Yoon Choi;Inwook Choi;Jinyoung Hur
    • Journal of the Korean Society of Food Culture
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    • v.38 no.3
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    • pp.176-183
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    • 2023
  • In this study, we investigated the effect of the extracts of Cyrtomium fortunei J.Sm. (CFJ) on lipopolysaccharide (LPS) induced inflammation in mouse BV-2 microglial cells. Nitric oxide (NO) production and cell viability were measured using the Griess reagent and the (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) (MTT) assay. Inflammatory cytokines were detected by quantitative polymerase chain reaction (qPCR) in BV-2 microglial cells with and without CFJ extracts. Subsequently, mitogen-activated protein kinases (MAPKs) and antioxidant markers were assessed by western blot analysis. It was found that the CFJ extract significantly decreased the production of pro-inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor [TNF]-α, and IL-1β) and NO in BV-2 microglial cells that were stimulated with LPS. In addition, the expression levels of the phosphorylation of the MAPK family (p38, c-Jun N-terminal kinases [JNK], and extracellular-signal regulated kinase [ERK]) were reduced by CFJ. Also, treatment with CFJ significantly increased the activities of superoxide dismutase type 1(SOD1) and Catalase in BV-2 microglial cells. Our results indicate that CFJ has a potent suppressive effect on the pro-inflammatory responses of activated BV-2 microglia. Therefore, CFJ has the potential to be an effective treatment for neurodegenerative diseases, as it can inhibit the production of inflammatory mediators in activated BV-2 microglial cells.