• Title/Summary/Keyword: $S_N2$ reaction

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DNA Polymorphism in 5'-Flanking Region of Human Apolipoprotein A1 and Glutathione S-Transferase Mu1 Gene in Koreans

  • Jeong, Gi-Hwa;Kim, Hyeon-Seop;Lee, Hyeon-Suk;Choe, Wi-Hyeong;Kim, Jun-Gi;Lee, Yeon-Suk;Kim, Nam-Geun;Lee, Gyeong-Ryeong;Lee, Jeong-Chu
    • Animal cells and systems
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    • v.1 no.2
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    • pp.351-354
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    • 1997
  • The distributions of G to A substitution ($G^{-75}{\rightarrow}A$) mutation in the human apolipoprotein A1 (APOAI) gene promoter region and glutathione S-tran-sferase Mu1 (GSTM1) gene deletion were examined in subjects with Korean population. The $G^{-75}{\rightarrow}A$ mutation of APOA1 was genotyped by the polymerase chain reaction (PCR) and subsequent digestion of the PCR product using either Mspl or Mval (n=206). The observed numbers of GG, GA and AA genotypes were 132, 63 and 11, respectively. The allele frequencies of G and A were 0.794 and 0.206, respectively. The GSTM1 gene deletion was simply examined by the PCR amplification (n=106). The observed numbers of null type ($GSTM1^*0/GSTM1^*0$) and positive type were 55 and 51, respectively. The allele frequency of $GSTM1^*0$ was 0.720.

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Adhesion Properties between Polyimide Film and Copper by Ion Beam Treatment and Imidazole-Silane Compound (이온빔 및 이미다졸-실란 화합물에 의한 폴리이미드 필름과 구리의 접착 특성)

  • Kang, Hyung Dae;Kim, Hwa Jin;Lee, Jae Heung;Suh, Dong Hack;Hong, Young Taik
    • Journal of Adhesion and Interface
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    • v.8 no.1
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    • pp.15-27
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    • 2007
  • Polyimide (PI) surface modification was carried out by ion-beam treatment and silane-imidazole coupling agent to improve the adhesion between polyimide film and copper. Silane-imidazole coupling agent contains imidazole functional groups for the formation of a complex with copper metal through a coordination bonding and methoxy silane groups for the formation of siloxane polymers. The PI film surface was first treated by argon (Ar)/oxygen ($O_2$) ion-beam, followed by dipping it into a modified silane-imidazole coupling agent solution. The results of X-ray photoelectron spectroscopy (XPS) spectra revealed that the $Ar/O_2$ plasma treatment formed oxygen functional groups such as hydroxyl and carbonyl groups on the polyimide film surface and confirmed that the PI surface was modified by a coupling reaction with imidazole-silane coupling agent. Adhesion between copper and the treated PI film by ion-beam and coupling agent was superior to that with untreated PI film. In addition, adhesion of PI film treated by an $Ar/O_2$ plasma to copper was better than that of PI film treated by a coupling agent. The peeled-off layers from the copper-PI film joint were completely different in chemical composition each other. The layer of PI film side showed similar C1s, N1s, O1s spectra to the original Upilex-S and no Si and Cu atoms appeared. On the other hand the layer of copper side showed different C1s and N1s spectra from the original PI film and many Si and Cu atoms appeared. This indicates that the failure occurs at an interface between the imidazole-silane and PI film layers rather than within the PI layers.

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Fabrication of P-type Transparent Oxide Semiconductor SrCu2O2 Thin Films by RF Magnetron Sputtering (RF 마그네트론 스퍼터링을 이용한 p 타입 투명전도 산화물 SrCu2O2 박막의 제조)

  • Seok, Hye-Won;Kim, Sei-Ki;Lee, Hyun-Seok;Lim, Tae-Young;Hwang, Jong-Hee;Choi, Duck-Kyun
    • Korean Journal of Materials Research
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    • v.20 no.12
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    • pp.676-680
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    • 2010
  • Most TCOs such as ITO, AZO(Al-doped ZnO), FTO(F-doped $SnO_2$) etc., which have been widely used in LCD, touch panel, solar cell, and organic LEDs etc. as transparent electrode material reveal n-type conductivity. But in order to realize transparent circuit, transparent p-n junction, and introduction of transparent p-type materials are prerequisite. Additional prerequisite condition is optical transparency in visible spectral region. Oxide based materials usually have a wide optical bandgap more than ~3.0 eV. In this study, single-phase transparent semiconductor of $SrCu_2O_2$, which shows p-type conductivity, have been synthesized by 2-step solid state reaction at $950^{\circ}C$ under $N_2$ atmosphere, and single-phase $SrCu_2O_2$ thin films of p-type TCOs have been deposited by RF magnetron sputtering on alkali-free glass substrate from single-phase target at $500^{\circ}C$, 1% $H_2$/(Ar + $H_2$) atmosphere. 3% $H_2$/(Ar + $H_2$) resulted in formation of second phases. Hall measurements confirmed the p-type nature of the fabricated $SrCu_2O_2$ thin films. The electrical conductivity, mobility of carrier and carrier density $5.27{\times}10^{-2}S/cm$, $2.2cm^2$/Vs, $1.53{\times}10^{17}/cm^3$ a room temperature, respectively. Transmittance and optical band-gap of the $SrCu_2O_2$ thin films revealed 62% at 550 nm and 3.28 eV. The electrical and optical properties of the obtained $SrCu_2O_2$ thin films deposited by RF magnetron sputtering were compared with those deposited by PLD and e-beam.

Pentachlorophenol(PCP) Decomposition by the Electron-beam Process (전자빔 공정에 의한 Pentachlorophenol 분해)

  • Kwon, Joongkuen;Kim, Jongoh;Kwon, Bumgun
    • Journal of the Korean GEO-environmental Society
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    • v.13 no.7
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    • pp.49-54
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    • 2012
  • This study focuses on the decomposition of pentachlorophenol(PCP) by an electron beam (E-beam) process. To attain this objective, we investigated the reactive species generated from E-beam process during irradiation (reaction time 0.6 s) and G-values of PCP decomposition and effects of pH and $H_2O_2$ as an additive. The effect of pH values was independent on the decomposition of PCP. However, during E-beam irradiation a scavenging effect of added $H_2O_2$ (> 1mM) for the decomposition of PCP was shown, which was supported by the decreased amounts of $Cl^-$ produced by the decomposition of PCP. Meanwhile, oxalic acid and unidentified organic chlorine compounds as by-products were increased by the addition of $H_2O_2$. Thus, in order to enhance the efficiency of PCP decomposition, the E-beam process has to consider a proper concentration of $H_2O_2$ as a well-known source of strong oxidant hydroxyl radical.

Evaluation of Drug Use Causing Delirium and Drowsiness in Elderly Patients of Korea (한국의 노인환자에 대한 섬망 및 졸음 유발 약물의 사용평가)

  • Cho, Ha-Na;Lee, Ok-Sang;Lim, Sung-Cil
    • Korean Journal of Clinical Pharmacy
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    • v.22 no.1
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    • pp.30-40
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    • 2012
  • In Korea, elderly population aged 65 and older are about 5.0% and 10.7% in 1990 and 2009, respectively. Since elderly people may experience physiologic changes with aging and their pharmacodynamic and pharmcokinetic parameters also have been undergone changes, several adverse drug reactions can occur more frequently than young people. Especially, neuropsychiatric adverse drug reactions such as delirium and drowsiness endanger elderly patients more. The purpose of this study is to evaluate the outpatient prescriptions using drug causing delirium and drowsiness in elderly patients aged 65 and older. We retrospectively reviewed prescriptions for elderly patients collected from four community pharmacies from January 2nd to February 1st, 2010. One pharmacy was located closed to a general hospital, and others were located closed to a internal medicine or an ENT clinic. The each number of the collected prescriptions was followings; Group A (n=496) from internal medicine department of a general hospital; Group B (n=44) from ENT department of general hospital; Group C (n=144) from internal medicine clinic; Group D (n=110) from ENT clinic. In result, in Group A, the average number of prescribed drugs causing delirium or drowsiness per Rx was 2.38 In Group B, the average number of prescribed drugs causing delirium or drowsiness per Rx was 2.09 In Group C, the average number of prescribed drugs causing delirium or drowsiness per Rx was 2.51. In Group D, the average number of prescribed drugs causing delirium or drowsiness per Rx was 2.72. Especially, in Group D, the percentage of prescription that drugs causing delirium or drowsiness per Rx prescribed more than 3 is 52.73% In all the 4 groups, over the 60% of drugs causing delirium and/or drowsiness per prescription of elderly patients were prescribed. It means elderly patients take 2 drugs causing delirium and/or drowsiness among 3 drugs, which is very serious. Frequently prescribed drugs causing delirium and/or drowsiness were followings; GI agents, antitussives & expectorants, histamine H1 antagonist, analgesics, antibiotics. Among these drugs, GI agents was high raking in all the 4 groups, and pharmacists should caution elderly patients when counseling. In the internal medicine groups (Group A,C), drugs concerning chronic diseases were prescribed frequently. In conclusion, pharmacist's role is important. Pharmacists are well informed of the drugs causing delirium or drowsiness and it is important to explain about ADRs slowly and easily to the elderly patients that receive drugs causing delirium or drowsiness. And institutional device is needed. For example, when doctors prescribe drugs for the elderly patients, message is needed that supply some informations about drugs causing delirium or drowsiness.

Is Genotypic Resistance-guide Eradication Therapy Effective for Patients with Refractory Helicobacter pylori Infection? (불응성 Helicobacter pylori 감염 환자들에게 유전자형 내성을 기반한 제균 치료는 유용한가?)

  • Kim, Sung Eun
    • The Korean journal of helicobacter and upper gastrointestinal research
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    • v.18 no.4
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    • pp.277-279
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    • 2018
  • 전 세계적으로 Helicobacter pylori의 항생제 내성률은 지속적으로 증가하고 있으며, 기존의 제균 치료에 실패한 H. pylori 감염 환자들에 대한 효과적인 구제요법(rescue therapy)의 필요성 역시 증가하고 있다. 이 연구는 두 개 기관, 공개, 평행 그룹, 무작위 배정 연구로서 불응성 H. pylori 감염 환자들의 구제요법으로 유전자형 내성을 기반한 치료(genotype resistance-guided therapy)와 경험적 치료(empirical therapy) 중 어느 것이 보다 효과적인지를 비교하고자 하였다. 2012년 10월부터 2017년 9월까지 20세 이상의 불응성 H. pylori 감염 환자들을 대상으로 하였으며, 불응성 H. pylori 감염은 과거 두 종류 이상의 H. pylori 제균 치료를 받았음에도 불구하고 H. pylori 제균에 실패한 환자들로 정의하였다. 이들에게서 한 군은 14일간의 유전자형 내성을 기반한 순차 치료(n=21 in trial 1, n=205 in trial 2)를, 다른 한 군은 환자들의 과거 제균 치료 종류를 감안한 14일간의 경험적 순차 치료(n=20 in trial 1, n=205 in trial 2)를 시행하였다. 순차 치료법은 첫 7일은 esomeprazole 40 mg과 amoxicillin 1 g을 하루 두 번 복용한 다음, 나머지 7일은 esomeprazole 40 mg과 metronidazole 500 mg, 그리고 1) levofloxacin 250 mg 또는 2) clarithromycin 500 mg 또는 3) tetracycline 500 mg을 하루 두 번 복용하는 것으로 구성하였다. 23S ribosomal RNA (rRNA)나 gyrase A에 대한 내성 관련 돌연변이 여부는 direct sequencing을 통한 중합효소연쇄반응(polymerase chain reaction, PCR) 검사를 이용하였고, 제균 성공 여부는 요소호기검사를 통해 확인하였다. 일차 결과 지표는 치료 방법에 따른 제균율로 정하였다. Trial 1에서는 tetracycline 대신 doxycycline 100 mg을 사용하였는데, 제균 성공률이 유전자형 내성을 기반한 치료군에서는 17명(81%), 경험적 치료군에서는 12명(60%)으로 나타났다(P=0.181). 하지만, 다른 순차 치료군들과 비교하였을 때, doxycycline을 포함한 순차 치료군의 제균율이 현저히 낮은 것으로 나타나서(15/26, 57.7%) doxycycline을 포함한 순차 치료법은 종결하기로 하고, trial 2부터는 doxycycline 대신 tetracycline으로 교체하여 연구를 지속하였다. Trial 2의 intention-to-treat (ITT) 분석 결과, 유전자형 내성을 기반한 치료군에서는 160/205명(78%), 경험적 치료군에서는 148/205명(72.2%)으로 두 그룹 간의 통계적인 제균율의 차이는 보여주지 못하였다(P=0.170). 부작용 및 환자 순응도에서도 양 군 간의 의미 있는 차이는 없었다. 따라서, 두 종류 이상 H. pylori 제균 치료에 실패한 환자들이라고 할지라도 기존의 제균 치료력을 바탕으로 적절한 경험적 치료를 시행하는 것은 유전자형 내성을 기반한 치료 정도의 효과는 있으며 접근성, 비용, 환자들의 선호도 등의 여러 가지 부가적인 사항들을 고려할 때, 제균 치료력을 고려한 경험적 치료는 간단한 수준의 유전자형 내성을 기반한 치료의 대안으로 받아들여질 수 있을 것으로 제안하였다.

Regulation of Prolactin Secretion: Dopamine is the Prolactin-release Inhibiting Factor (PIF), but also Plays a Role as a Releasing Factor (PRF)

  • Shin, Seon H.;Song, Jin-Hyang;Ross, Gregory M.
    • Animal cells and systems
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    • v.3 no.2
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    • pp.103-113
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    • 1999
  • Many in-depth reviews related to regulations of prolactin secretion are available. We will, therefore, focus on controversial aspects using personal opinion in this review. The neuroendocrine control of prolactin secretion from the anterior pituitary gland involves multiple factors including prolactin-release inhibiting factor (PIF) and prolactin releasing factor (PRF). The PIF exerts a tonic inhibitory control in the physiological conditions. The PIF should be able to effectively inhibit prolactin release or a lifetime, but the inhibitory action of dopamine cannot be sustained for a long period of time. Perifusion of a high concentration of dopamine (l ,000 nM) could not sustain inhibitory action on prolactin release but when a small amount of ascorbic acid (0.1 mM) is added in a low concentration of dopamine (3 nM) solution, prolactin release was inhibited for a long period. Ascorbate is essential for dopamine action to inhibit prolactin release. We have, therefore, concluded that the PIF is dopamine plus ascorbate. The major transduction system for dopamine to inhibit prolactin release is the adenylyl cyclase system. Dopamine decreases cyclic AMP concentration by inhibiting adenylyl cyclase, and cyclic AMP stimulates prolactin release. However, the inhibitory mechanism of dopamine on prolactin release is much more complex than simple inhibition of CAMP production. The dopamine not only inhibits cyclic AMP synthesis but also inhibits prolactin release by acting on a link(s) after the CAMP event in a chain reaction for inhibiting prolactin release. Low concentrations of dopamine stimulate prolactin release. Lactotropes are made of several different subtypes of cells and several different dopamine receptors are found in pituitary. The inhibitory and stimulatory actions induced by dopamine can be generated by different subtype of receptors. The GH$_4$ZR$_7$ cells express only the short isoform (D$_{2s}$) of the dopamine receptor, as a result of transfecting the D$_{2s}$ receptors into GH$_4$C$_1$ cells which do not express any dopamine receptors. When dopamine stimulates or inhibits prolactin release in GH$_4$ZR$_7$ cells, it is clear that the dopamine should act on dopamine D$_{2s}$ receptors since there is no other dopamine receptor in the GH$_4$ZR$_7$. Dopamine is able to stimulate prolactin release in a relatively low concentration while it inhibits in a high concentration in GH$_4$ZR$_7$. These observations indicate that the dopamine D$_2$ receptor can activate stimulatory and/or inhibitory transduction system depending upon dopamine concentrations.

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Changes of Glycosidase Activity of Frozen-Thawed Spermatozoa in Human

  • Lee, Chae-Sik;Lee, Sang-Chan;Lee, Ji-Eun;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Reproductive and Developmental Biology
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    • v.35 no.2
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    • pp.185-190
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    • 2011
  • To evaluate the effect of spermatozoa culture on glycosidase activity of frozen-thawed spermatozoa in human, the spermatozoa were treated experimentally and assayed for activities of ${\alpha}$-L-fucosidase, ${\alpha}$-D-mannosidase, ${\beta}$-D-galactosidase and N-acetyl-${\beta}$-D-glucosaminidase (${\beta}$-GlcNAc'ase). The ${\beta}$-GlcNAc'ase activity was at least two-folds higher than other glycosidases regardless of spermatozoa incubation (p<0.05). The spermatozoa motility was decreased with incubation periods, but no effects by different glycosidases on the changes of spermatozoa motility during the various periods of incubation. In all glycosidases, the spermatozoa-zona binding rates in spermatozoa without incubation were higher than in spermatozoa incubated for 2 h (p<0.05). ${\beta}$-GlcNAc'ase is present mainly in the plasma membrane of spermatozoa frozen-thawed in human. It was also shown that the glycosidase activity was increased in all glycosidases in spite of lower sperm-zona binding by spermatozoa incubation.

Fabrication of Transition Metal doped Sapphire Single Crystal by High Temperature and Pressure Acceleration Method

  • Park, Eui-Seok;Jung, Choong-Ho;Kim, Moo-Kyung;Kim, Hyung-Tae;Kim, Yoo-Taek;Hong, Jung-Yoo
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1998.09a
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    • pp.97-102
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    • 1998
  • Transition metal Cr3+ and Fe3+ ion was diffused in white sapphire {0001}, {1010} crystal plane which were grown by the Verneuil method. It enhanced and changed the physical, electrical and optical properties of sapphires. After mixing the metallic oxide and metal powder, it were used for diffusion. Metallic oxide was synthesized by precipitation method and it's composition was mainly alumina which doped with chromium or ferric oxide. In case using metallic oxide, the dopping was slowly progressed and it needed the longer duration time and higher temperature, relatively. Metallic powder was vapoured under 1x10-4 torr of vacuum pressure at 1900(iron metal) and 2050(chromium)℃, first step. Diffusion condition were kept by 6atm of N2 accelerating pressure at 2050∼2150℃. Each surface density of sapphire crystal are 0.225(c) and 0.1199atom/Å2(a). The color of the Cr-doped sapphires was changed to red. Dopping reaction was come out more deep in th plane of {1010} than {0001}. It was speculated that the planar density was one of the factors to determine diffusion effect.

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Effects of Gym Ball Stabilization Exercises on the Physical Functions of Elementary School Baseball Players

  • Kim, Se-Hun;Park, Jea-Cheol
    • The Journal of Korean Physical Therapy
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    • v.34 no.2
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    • pp.51-56
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    • 2022
  • Purpose: This study examined the effects of gym ball stabilization exercises on the physical functions of elementary school baseball players. Methods: The elementary school baseball players were assigned to an experimental group (n=21). The group performed gym ball stabilization exercises and the changes in the physical functions were measured using the visual response speed test, functional movements, physical balance ability, and pulmonary function. Results: The results of the visual response speed test showed changes in the time response speed. There was a significant change in the number of touches in 15 seconds in the upper arms and left and right legs (p<0.05) after 10 weeks. Also, there was a significant change in the reaction times of the left and right legs after 10 weeks (p<0.05). Further, there were significant differences in functional movements involving rotational stability and the total functional scores after 10 weeks (p<0.05). The player's body balance ability showed a significant difference after 10 weeks in the posterior-lateral and posterior-medial composite scores of the left and right legs (p<0.05). There was a significant change in the forced lung capacity and forced expiratory volume in 1 second after 10 weeks (p<0.05). Conclusion: These results show that the gym ball stabilization exercises effectively improved the visual response speed and functional movements, balance, and vital capacity of elementary school baseball players.