• Title/Summary/Keyword: $\beta$-type

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Kinetic Studies on the Nucleophilic Addition of Thiourea to ${\beta}$-Nitrostyrene Derivatives (${\beta}$-Nitrostyrene 유도체에 대한 Thiourea의 친핵성 첨가반응에 관한 반응속도론적 연구)

  • Tae-Rin Kim;Yeun-Soo Chung;Myung-Sook Chung
    • Journal of the Korean Chemical Society
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    • v.35 no.3
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    • pp.268-274
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    • 1991
  • The rate constants for the nucleophilic addition reactions of thiourea to ${\beta}$-nitrostyrene derivatives(p-H, p-Cl, p-CH$_3$, p-OCH$_3$, p-NO$_2$) were determined by UV spectrophotometer and rate equations which can be applied over a wide pH ranges were obtained. On the basis of substituent effect, general base catalysis and rate equations, a reaction mechanism was proposed and revealed quantitively. Above pH 9.00, sulfide anion adds to the double bond(Michael type addition) and between pH 7.00 and 9.00, the neutral molecules and its anions add to the double bond competitively. Below pH 7.00, the addition reaction to double bond is initiated by the addition of neutral thiourea molecule.

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Percutaneous Absorption and Model Membrane Variations of Melatonin in Aqueous-based Propylene Glycol and 2-Hydroxypropyl-$\beta$-cyclodextrin Vehicles

  • Lee, Beom-Jin;Cui, Jing-Hao;Keith A. Parrott;James W.Ayres;Robert L.Sack
    • Archives of Pharmacal Research
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    • v.21 no.5
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    • pp.503-507
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    • 1998
  • Percutaneous absorption and model membrane variations of melationin (MT) in aqueous-based propylene glycol and $2-hydroxypropyl-{\beta}-cyclodextrin $vehicles were investigatted. the excised hairless mouse skin (HMS) and two synthetic ethylene vinyl acetate (EVA) and microporous polyethylene (MPE) were selected as a model membrane. the solubility of MT was determined by phase equilibrium study. the vertical $Franz{\circledR}$ type cell was used for diffusion study. The concentration of MT was determined using reverse phse HPLC system. The MT solubility was the highest in a mixture of PG and $2-HP{\beta}CD$. The percutaneous absorption of MT through excised HMS increased as the solubility increased. However, the permeability coefficient decreased and then slightly increased in mixture of PG and $2-HP{\beta}CD$. On the other hand, both flux and permeability coefficient through EVA membrane decreased as the solubility increased. No MT was detected over 12 h after starting diffusion through MPE membrane. The flux of MT was dependent on the type of membrane selected. Flux of MT was greatest in excised HMS followed by EBA and MPE membrane. Flux of MT through EVA membrane was 5-20 times lower when compared to excised HMS. Interestingly, volumes of donor phase when MPE membrane was used, significantly increased during the study period. the HMS might be applicable to expect plasma concentration of MT in human subjects based on flux and pharmacokinetic parameters as studied previously. the current studies may be applied to deliver MT transdermally using aqueous-based vehicles and to fabricate MT dosage forms.

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Antiviral activity of methanol extract from Rhus chinensis gall (오배자 추출물의 항바이러스 활성)

  • Lee, Doseung;Min, TaeSun;Lee, Dong-Sun
    • Journal of Applied Biological Chemistry
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    • v.61 no.4
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    • pp.379-382
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    • 2018
  • Trafficking process of viral glycoprotein to cell surface results in the syncytium formation when baby hamster kidney (BHK) cells was infected by Newcastle disease virus (NDV). Rhus chinensis gall, well-known as a medicinal plant, inhibited not only syncytium formation, but also trafficking of glycoprotein, hemagglutinin-neuramidase (HN) to the cell-surface. Modification of viral glycoprotein is processed within the endoplasmic reticulum and golgi body during trafficking into surface. R. chinensis gall extracts showed the strong inhibitory activities ($IC_{50}$ $12.5{\mu}g/mL$) against ${\alpha}-glucosidase$, when compared with the ${\beta}-glucosidase$. And this inhibitory activities is increased by the samples in a dose-depedent pattern. These data showed that the extracts of R. chinensis gall inhibited the cell-surface expression of NDV-hemagglutinin-neuramidase glycoprotein without significantly affecting HN glycoprotein synthesis in NDV-infected BHK cells.

Genetic Analysis of Spontaneous Lactose-Utilizing Mutants from Vibrio vulnificus

  • Baek, Chang-Ho;Lee, Ko-Eun;Park, Dae-Kyun;Choi, Sang-Ho;Kim, Kun-Soo
    • Journal of Microbiology and Biotechnology
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    • v.17 no.12
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    • pp.2046-2055
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    • 2007
  • Wild-type V. vulnificus cannot grow using lactose as the sole carbon source or take up the sugar. However, prolonged culture of this species in media containing lactose as the sole carbon source leads to the generation of a spontaneous lactose-utilizing (LU) mutant. This mutant showed strong ${\beta}$-galactosidase activity, whereas the wild-type strain showed a barely detectable level of the activity. A mutant with a lesion in a gene homologous to the lacZ of E. coli in the bacterium no longer showed ${\beta}$-galactosidase activity or generated spontaneous LU mutants, suggesting that the lacZ homolog is responsible for the catabolism of lactose, but the expression of the gene and genes for transport of lactose is tightly regulated. Genetic analysis of spontaneous LU mutants showed that all the mutations occur in a lacI homolog, which is located downstream to the lacZ and putative ABC-type lac permease genes. Consistent with this, a genomic library clone containing the lad gene, when present in trans, made the spontaneous LU mutants no longer able to utilize lactose as the sole carbon source. Taken together with the observation that excessive amounts of exogenously supplemented possible catabolic products of lactose have negative effects on the growth and survivability of V. vulnificus, we suggest that V. vulnificus has evolved to carry a repressor that tightly regulates the expression of lacZ to keep the intracellular toxic catabolic intermediates at a sublethal level.

Fitting Bivariate Generalized Binomial Models of the Sarmanov Type (Sarmanov형 이변량 일반화이항모형의 적합)

  • Lee, Joo-Yong;Kim, Kee-Young
    • The Korean Journal of Applied Statistics
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    • v.22 no.2
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    • pp.271-280
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    • 2009
  • For bivariate binomial data with both intra and inter-class correlation, Danaher and Hardie (2005) proposed a bivariate beta-binomial model. However, the model is limited to the situation where the intra-class correlation is strictly positive. Thus it might be seriously inadequate for data with a negative intra-class correlation. Several authors have considered generalized binomial distributions covering a wider range of intra-class correlation which could relax the possible model restrictions imposed. Among others there are the additive/multiplicative and the beta/extended beta binomial model. In this study, bivariate models of the Sarmanov (1966) type are formed by combining each of those univariate models to take care of the inter-class correlation, and are evaluated in terms of the goodness-of-fit. As a result, B-mB and B-ebB are fitted, successfully, to real data and that B-mB, which has a wider permissible range than B-ebB for the intra-class correlation is relatively preferred.

The Effects of Aurothiomalate acupuncture on Type II Collagen-induced Arthritis (금주사액약침(金注射液藥鍼)이 제2형 콜라겐 유도 관절염(關節炎)에 미치는 영향(影響))

  • Kim, Kyeong-Min;Choi, Do-Young;Park, Dong-Sukm;Lee, Yun-Ho
    • Journal of Acupuncture Research
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    • v.19 no.3
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    • pp.14-25
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    • 2002
  • Objective : The purpose of this study was to investigate the effects of Aurothiomalate acupuncture containing Sodium Aurothiomalate on Type II collagen-induced arthritic DBA/1 mice. Methods : The mice were divided into three groups, one control group and two test groups. The control group was injected with saline on Choksamni(ST36) and the two test groups were injected either with Aurothiomalate acupuncture into Choksamni(AT1 group), or with Aurothiomalate acupuncture into Hwando(G30, AT2 group). We measured the incidence of arthritis, the mean index of arthritis, the number of arthritic limbs for the clinical examination and evaluation. We also examined the changes in the level of TNF-$\alpha$ and IL-$1{\beta}$. Results : 1. The incidence of arthritis in mice of the AT1 and AT2 groups were significantly lower than that of the control group. 2. The mean indices of arthritis in mice of the AT1 and AT2 groups were significantly lower than that of the control group. 3. The mean number of arthritic limbs in mice of the AT1 and AT2 groups were significantly lower than that of the control group. 4. The levels of TNF-$\alpha$ of the mice in the AT1 and AT2 groups were significantly different from that of the control group. 5. The levels of IL-$1{\beta}$ of the mice in the AT1 and AT2 groups were not significantly different from that of the control group. Conclusion : These results indicate that the treatment with Aurothiomalate acupuncture could improve the clinical status of Arthritis by suppressing immune responses in the mice of Type II collagen-induced arthritic.

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Effect of Scutellaria barbata Pharmacopuncture Extract on Degranulation and Inflammatory Mediator Release in RBL-2H3 Cells (반지련 약침 추출물의 RBL-2H3 세포 탈과립과 염증매개물질 분비 억제 효과)

  • Kwon, Hyuk-Sang;Song, Choon-Ho
    • Korean Journal of Acupuncture
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    • v.29 no.3
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    • pp.406-420
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    • 2012
  • Objectives : Scutellaria barbata has been widely used in oriental medicine used for treatment of acute and chronic inflammatory diseases. In this study, to investigate the protective effect of Scutellaria barbata on type I allergic response, we determined whether Scutellaria barbata inhibits early or late allergic responses. Methods : To assess the effect of Scutellaria barbata Pharmacopuncture Extract(SB) in RBL-2H3 cells, we investigated the levels of the markers of degranulation such as ${\beta}$-hexosaminidase and histamine, inflammatory mediator such as IL-4, TNF-${\alpha}$, PGE2 and cysLT, and mRNA expression of cytokines and enzymes. In addition, we determined the levels of intracellular ROS by DCFH-DA assay and the free radical scavenging activity by DPPH method. Results : We found that SB suppressed the release of ${\beta}$-hexosaminidase and histamine and the production of IL-4, TNF-${\alpha}$, PGE2 and cysLT in RBL-2H3 by the antigen stimulation. SB also significantly inhibited the enzyme mRNA expressions, such as HDC2, COX-1, COX-2, 5-LOX and iNOS2, along with reduced cytokine mRNA expressions, such as IL-$1{\beta}$, IL-2, IL-3, IL-4, IL-5, IL-6, IL-13, TNF-${\alpha}$ and GM-CSF in RBL-2H3. In addition, SB suppressed the levels of intracellular ROS. Conclusions : Our results indicate that SB protects against type I allergic response and exert an anti-inflammatory effect through the inhibition of degranulation, inflammatory mediator release and mRNA expression of cytokines and enzymes.

Kinetic Study on Aminolysis of 4-Pyridyl X-Substituted Benzoates: Effect of Substituent X on Reactivity and Reaction Mechanism

  • Lee, Jong-Pal;Bae, Ae-Ri;Um, Ik-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.32 no.6
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    • pp.1907-1911
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    • 2011
  • A kinetic study is reported for nucleophilic substitution reactions of 4-pyridyl X-substituted benzoates 7a-e with a series of alicyclic secondary amines in H2O. The Br${\o}$nsted-type plot for the reactions of 4-pyridyl benzoate 7c is linear with ${\beta}_{nuc}$ = 0.71. The corresponding reactions of 2-pyridyl benzoate 6, which is less reactive than 7c, resulted in also a linear Br${\o}$nsted-type plot with ${\beta}_{nuc}$ = 0.77. The fact that the more reactive 7c results in a smaller ${\beta}_{nuc}$ value appears to be in accord with the reactivity-selectivity principle. The aminolysis of 7c has been suggested to proceed through a stepwise mechanism in which breakdown of the intermediate is the rate-determining step (RDS). The Hammett plot for the reactions of 7a-e with piperidine consists of two intersecting straight lines, i.e., ${\rho}_X$ = 1.47 for substrates possessing an electron-donating group (EDG) and ${\rho}_X$ = 0.91 for those possessing an electron-withdrawing group (EWG). In contrast, the corresponding Yukawa-Tsuno plot exhibits excellent linear correlation with ${\rho}_X$ = 0.79 and r = 0.56. Thus, it has been concluded that the nonlinear Hammett plot is not due to a change in the RDS but is caused by stabilization of the ground state of the substrates possessing an EDG through resonance interaction between the EDG and the C=O bond of the substrates.

Action of Crude Amylolytic Enzymes Extracted from Sweet Potatoes and Amylolytic Enzymes on the Sweet Potato Starches (고구마 전분에 대한 고구마 조효소와 전분분해 효소의 작용에 관하여)

  • Shin, Mal-Shick;Ahn, Seung-Yo
    • Korean Journal of Food Science and Technology
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    • v.18 no.6
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    • pp.431-436
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    • 1986
  • The action of crude amylolytic enzymes extracted from Wonki and Chunmi sweet potatoes, ${\alpha}-amylase$, and ${\beta}-amylase$ on the sweet potato starches from Wonki (dry type) and Chunmi (moist type) were studied. The activity of crude amylolytic enzyme extracted from Wonki was higher than that extracted from Chunmi. The content of reducing sugar released from the reaction between crude amylolytic enzyme and Chunmi starch preheated at $70^{\circ}C$ was higher, but that preheated at $95^{\circ}C$ was lower than that from Wonki starch preheated at the same temperature. The activites of ${\alpha}-amylase$ and ${\beta}-amylase$ on the Wonki starch were higher than those of the Chunmi starch at the same conditions. Iodine affinity of amylolytic enzyme-treated starch was decreased and enzyme treated starch granule shape was found with porous structure having inner layers. X-ray diffraction patterns of amylolytic enzyme-treated starches were the Ca type like the intact starches and relative crystallinity was decreased.

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A Case of Krabbe Disease with Infantile Spasm (영아 연축을 동반한 Krabbe병 1례)

  • Kim, Ja Kyoung;Kim, Dal Hyun;Kang, Bo Young;Kwon, Young Se;Hong, Young Jin;Son, Byong Kwan;Yoon, Hye Ran
    • Clinical and Experimental Pediatrics
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    • v.46 no.1
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    • pp.95-99
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    • 2003
  • Krabbe disease is a rare autosomal recessive disorder clinically characterized by retardation in motor development, prominent spasticity, seizures, and optic atrophy. Pathologically, there are many globoid cells in the white matter, in addition to the lack of myelin and the presence of severe gliosis. Hence Krabbe disease is known as globoid cell leukodystrophy. Biochemically, the primary enzymatic deficiency in Krabbe disease is galactocerebroside beta-galactosidase. Patients with Krabbe disease can be subdivided into the early-onset type and late-onset type, according to the onset of clinical manifestations. Most patients with early-onset type die before their second birthday. We describe a girl with Krabbe disease associated with uncontrolled seizures, which was confirmed with biochemical study and MRI. The clinical findings of this patient included hyperirritability, scissoring of the legs, flexion of arm, and clenching of the fists, and generalized tonic seizures. EEG showed hypsarrhythmia, and MRI demonstrated degenerative white matter changes in bilateral periventricular white matter, posterior rim of internal capsule, basal ganglia and brain stem on T2W1 and FLAIR image. The diagnosis was based on clinical features of progressive neurologic deterioration in conjunction with low galactocerebroside beta-galactosidase activity.