• Title/Summary/Keyword: Delta activity

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Pharmacokinetic and Pharmacodynamic Characterization of Gliclazide in Healthy Volunteers

  • Kim, Ho-Soon;Yun, Min-Hyuk;Kwon, Kwang-Il
    • Archives of Pharmacal Research
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    • v.26 no.7
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    • pp.564-568
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    • 2003
  • Pharmacokinetic and pharmacodynamic properties of gliclazide were studied after an oral administration of gliclazide tablets in healthy volunteers. After an overnight fasting, gliclazide tablet was orally administered to 11 volunteers; Additional 10 volunteers were used as a control group (i.e., no gliclazide administration). Blood samples were collected, and the concentration determined for gliclazide and glucose up to 24 after the administration. Standard pharmacokinetic analysis was carried out for gliclazide. Pharmacodynamic activity of the drug was expressed by increase of glucose concentration ($\Delta$PG), by area under the increase of glucose concentration-time curve ($AUC_{$\Delta$PG}$) or by the difference in increase of glucose concentration ($D_{$\Delta$PG}$) at each time between groups with and without gliclazide administration. Pharmacokinetic analysis revealed that $C_{max}, T_{max}$, CL/F (apparent clearance), V/F (apparent volume of distribution) and half-life of gliclazide were $4.69\pm1.38 mg/L, 3.45\pm1.11 h, 1.26\pm0.35 L/h, 17.78\pm5.27 L, and 9.99\pm2.15 h$, respectively. When compared with the no drug administration group, gliclazide decreased significantly the $AUC_{$\Delta$PG}$ s at 1, 1.5, 2, 2.5, 3 and 4 h (p<0.05). The $\Delta$PGs were positively correlated with $AUC_{gliclazide}$ at 1 and 1.5 h (p<0.05), and the correlation coefficient was maximum at 1 h (r = 0.642) and gradually decreased at 4 h after the administration. The $AUC_{$\Delta$PG}$s were positively correlated with $AUC_{gliclazide}$ at 1, 2, 3 and 4 h (p<0.05), and the maximum correlation coefficient was obtained at 2 h (r=0.642) after the administration. The $D_{$\Delta$PG}$ reached the maximum at 1 h, remained constant from 1 h to 3 h, and decreased afterwards. Therefore, these observations indicated that maximum hypoglycemic effect of gliclazide was reached at approximately at 1.5 h after the administration and the effect decreased, probably because of the homeostasis mechanism, in health volunteers.

THE ROLE OF MAPK AND PKC-${\delta}$ IN PHOSPHATIDIC ACID-MEDIATED INTERCELLULAR ADHESION MOLECULE-1 EXPRESSION (Phosphatidic acid에 의한 intercellular adhesion molecule-1 발현 조절에 관여한 MAPK와 PKC-${\delta}$의 역할)

  • Cho, Woo-Sung;Yoon, Hong-Sik;Chin, Byung-Rho;Baek, Suk-Hwan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.5
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    • pp.445-454
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    • 2007
  • Background: Phosphatidic acid(PA), an important second messenger, is involved in inflammation. Notably, cell-cell interactions via adhesion molecules playa central role in inflammation. This thesis show that PA induces expression of intercellular adhesion molecule-1(ICAM-1) on macrophages and describe the signaling pathways. Materials and methods: Macrophages were cultured in the presence of 10% FBS and assayed cell to cell adhesion using HUVEC. For the gene and protein analysis, RT-PCR, Western blot and flow cytometry were performed. In addition, overexpressed cell lines for dominant negative PKC-${\delta}$ mutant established and tested their effect on the promoter activity and expression of ICAM-1 protein by PA. Results: PA-activated macrophages significantly increased adhering to human umbilical vein endothelial cell and this adhesion was mediated by ICAM-1. Pretreatment with rottlerin(PKC-${\delta}$ inhibitor) or expression of a dominant negative PKC-${\delta}$ mutant, but not Go6976(classical PKC-${\alpha}$ inhibitor) and myristoylated PKC-${\xi}$ inhibitor, attenuated PA-induced ICAM-1 expression. The p38 mitogen-activated protein kinase(MAPK) inhibitor blocked PA-induced ICAM-1 expression in contrast, ERK upstream inhibitor didn't block ICAM-1. Conclusion: These data suggest that PA-induced ICAM-1 expression and cell-cell adhesion in macrophages requires PKC-${\delta}$ activation and that PKC-${\delta}$ activation is triggers to sequential activation of p38 MAPK.

Effects of δ-Catenin on APP by Its Interaction with Presenilin-1

  • Dai, Weiye;Ryu, Taeyong;Kim, Hangun;Jin, Yun Hye;Cho, Young-Chang;Kim, Kwonseop
    • Molecules and Cells
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    • v.42 no.1
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    • pp.36-44
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    • 2019
  • Alzheimer's disease (AD) is the most frequent age-related human neurological disorder. The characteristics of AD include senile plaques, neurofibrillary tangles, and loss of synapses and neurons in the brain. ${\beta}-Amyloid$ ($A{\beta}$) peptide is the predominant proteinaceous component of senile plaques. The amyloid hypothesis states that $A{\beta}$ initiates the cascade of events that result in AD. Amyloid precursor protein (APP) processing plays an important role in $A{\beta}$ production, which initiates synaptic and neuronal damage. ${\delta}-Catenin$ is known to be bound to presenilin-1 (PS-1), which is the main component of the ${\gamma}-secretase$ complex that regulates APP cleavage. Because PS-1 interacts with both APP and ${\delta}-catenin$, it is worth studying their interactive mechanism and/or effects on each other. Our immunoprecipitation data showed that there was no physical association between ${\delta}-catenin$ and APP. However, we observed that ${\delta}-catenin$ could reduce the binding between PS-1 and APP, thus decreasing the PS-1 mediated APP processing activity. Furthermore, ${\delta}-catenin$ reduced PS-1-mediated stabilization of APP. The results suggest that ${\delta}-catenin$ can influence the APP processing and its level by interacting with PS-1, which may eventually play a protective role in the degeneration of an Alzheimer's disease patient.

Rhizobium meliloti 102F51 Mutants Defective in Heme Synthesis (Heme 합성특성이 다른 Rhizobium meliloti 102F51 Mutant의 선별)

  • 최영주;정원화;김경수;신평균;조무제
    • Korean Journal of Microbiology
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    • v.24 no.2
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    • pp.98-105
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    • 1986
  • Rhizobium meliloti 102 F 51, the symbiotic partner of alfalfa, was mutagenized with N-methyl-N'-nitro-N-nitrosoguanidine (NTG) and UV-irradiation. Three group of mutants which form white, white-pink and red nodules were selected. The adetylene reduction activity, nodulation activity, amount of heme synthesis during the nodulation, and ${\delta}-aminolevulinic$ acid synthetase (ALAS) and ${\delta}-aminolevulinic$ acid dehydratase (ALAD) activities in free living rhizobia and bacteroid states of the each group of mutants were compared. The mutants forming white nodules showed lower acetylene reduction activity compared to those of red nodule forming mutants. The two key enzymes for the heme synthetic pathway, ALAS and ALAD activities of the mutants forming red nodules was much higher than those of the mutants forming white nodules in bacteroid state, however no significant difference was observed in free living state. In the nodules the ALAS was detected only in bacteroid fraction, while ALAD was detected both in bacteroid and plant fraction. ALAS was dramatically increased with the heme synthesis during the nodulation, while ALAD was decreased in plant fraction but slight increase was observed in bacteroid fraction.

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Interictal Epileptiform Discharges and Background Delta Frequency Bands in Scalp EEGs of Epileptic Patients: Anatomical Correlation between the Current Source Distributions (간질환자 두피뇌파의 발작사이간질모양방전과 배경파 델타영역: 전류원분포의 해부학적 연관성)

  • Jung, Seung-Uk;Kwon, Oh-Young;Kang, Jong-Soo;Ha, Eun-Ok;Jung, Seo-Kwon;Kang, Kyu-Sik;Kang, Hee-Young;Park, Ki-Jong;Choi, Nack-Cheon;Lim, Byeong-Hoon
    • Annals of Clinical Neurophysiology
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    • v.11 no.1
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    • pp.16-23
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    • 2009
  • Background: The intermittent delta activity in electroencephalographies (EEGs) of patients with focal brain lesions has been reported to be a marker of an epileptogenic focus. This study investigated the concordance between the current source distribution (CSD) of the interictal epileptiform discharges (IEDs) and that of the background delta frequency bands (DFBs) of the scalp EEG. Methods: We collected scalp EEGs of 13 patients with focal epilepsy that contained uniregional IEDs and unilateral delta to theta slow waves. We applied a distributed source model using LORETA$^{(R)}$ to determine the CSD of the peak points of the IEDs and the DFBs of the background activity. Results: The CSDs of the DFBs were ipsilateral to the CSDs of the peak point of the averaged IEDs in ten patients, and bilateral with ipsilateral predominance in three patients. In the cases with an ipsilateral CSD of the DFB, 8 of 10 patients had concordance of the CSD localization between the averaged IED and the DFB. In the cases with bilateral CSD of the DFB, 2 of 3 patients had concordance of the CSD localization between the averaged IED and the DFB. Conclusions: The CSD localization and lateralization appear to be concordant between the IEDs and the DFB of background activity in epileptic patients. Therefore, the CSD of the DFB in EEGs with visually observable slow activities may predict those of IEDs.

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DELTA OPIOID ANALGESICS

  • Burks, Thomas F.
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.50-62
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    • 1994
  • Opium, morphine and rotated natural and synthetic opiates have been used since antiquity, and to the present, for the relief of moderate and severe pain. Morphine and pharmacologically related drugs, however, produced an array of undesired or dangerous side effect that limit their use as analgesics. Prominent among the limiting side effects are constipation, respiratory depression, release of prolactin, and liability for the production of drug dependence. It was our aim to develop, if possible, a drug or class of drugs with analgesic activity similar to that of morphine, but without the serious side effects associated with morphine. Our overall strategy was to take advantage of advancing knowledge concerning multiple types of opioid receptors, to develop ligands selective for the delta type receptors, to determine whether delta receptor agonists offer advantages over mu agonists, then to design compounds with pharmacokinetic properties compatible with practical therapeutic application. All but the last of these objectives have been realized.

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Functions of the C-Terminal Region of Chitinase ChiCW from Bacillus cereus 28-9 in Substrate-Binding and Hydrolysis of Chitin

  • Huang, Chien-Jui;Chen, Chao-Ying
    • Journal of Microbiology and Biotechnology
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    • v.16 no.12
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    • pp.1897-1903
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    • 2006
  • In order to investigate the functions of the C-terminal region of chitinase ChiCW of Bacillus cereus 28-9, a C-terminal truncated enzyme, ChiCW$\Delta$FC, was expressed in Escherichia coli and purified to homogeneity for biochemical characterization. Compared with ChiCW, ChiCW$\Delta$FC exhibited higher chitinase activity at high temperature and pH, but expressed lower hydrolytic and binding activities toward insoluble substrates. In addition, kinetic properties indicated that ChiCW$\Delta$MC hydrolyzed oligomeric and polymeric substrates less efficiently than ChiCW. These results suggest that the C-terminal region of ChiCW plays important roles in substrate binding and hydrolysis of chitin. In addition, the biological meaning of C-terminal proteolytic modification of ChiCW is discussed.

Absorption Properties of Chitosan and Nano Silver Composite knit Fabrics Dyed with Chrysanthemum indicum Linn Extract (감국 추출액으로 염색한 키토산/나노실버 복합편성물의 염착특성)

  • Chu, Young-Ju
    • Fashion & Textile Research Journal
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    • v.12 no.6
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    • pp.837-842
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    • 2010
  • This study examines the dyeability, light fastness, washing fastness, and antibacterial activity of chitosan and nano silver composite knit fabrics dyed with extracted solution from Chrysanthemum Indicum Linn. The results show that ${\Delta}E$ values of chitosan and nano silver composite knit fabrics were higher than cotton 100% knit fabrics in dyed condition with extracted solution from Chrysanthemum Indicum Linn, and mordant treatments influenced the chrominance change. Chrysanthemum indicum Linn confirmed that this could be a polygenetic colors. ${\Delta}E$ values of post-mordant treatments knit fabrics were higher than pre-mordant treatments knit fabrics in dyed condition with extracted solution from Chrysanthemum Indicum Linn., and mordant treatments method influenced the chrominance change. The dyeability of chitosan and nano silver composite knit fabrics was increased by mordant treatment. The fastness of the chitosan and nano silver composite knit fabrics was better than cotton 100% knit fabrics. In the result of antibacterial activity, the bacterial reduction rate of chitosan and nano silver composite knit fabrics was 99.9% to Staphylococcus aureus and Klebsiella pneumoniae.

Mitochondria-Targeted Apoptosis in Human Cytomegalovirus-Infected Cells

  • Lee, Gyu-Cheol;Lee, Jae Ho;Kim, Bo Yeon;Lee, Chan Hee
    • Journal of Microbiology and Biotechnology
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    • v.23 no.11
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    • pp.1627-1635
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    • 2013
  • Mitochondria often play central roles in apoptotic pathways, and disruption of the mitochondrial transmembrane potential (${\Delta}{\psi}m$) has been observed in various cells undergoing apoptosis. Human cytomegalovirus (HCMV) infection induces apoptosis in permissive cells; however, investigations of mitochondria-targeted apoptosis in HCMV-infected human foreskin fibroblast (HFF) cells have been limited. Here, we investigated the mitochondrial apoptosis pathway in HCMV-infected HFF cells. Flow cytometry analysis using JC-1 revealed that HCMV infection induces disruption of ${\Delta}{\psi}m$ in HFF cells when administered 24 h post-infection (hpi), and this disruption was maximized at 48 hpi. Moreover, cytochrome c, normally a mitochondrial inner membrane protein, was detected in cytoplasmic extracts of HCMV-infected cells, but not mock-infected cells, by western blot analysis at 24 hpi. A caspase activity assay based on fluorescence spectrophotometry using a fluorogenic substrate revealed an increase in caspase-3 activity at 48 hpi in HCMV-infected cells. Caspase-8 activity was increased at 72 hpi in HCMV-infected cells. These results imply that HCMV infection induces mitochondria-mediated apoptosis in HFF cells.

Enzymatic properties of the N- and C-terminal halves of human hexokinase II

  • Ahn, Keun-Jae;Kim, Jong-Sun;Yun, Mi-Jin;Park, Jeon-Han;Lee, Jong-Doo
    • BMB Reports
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    • v.42 no.6
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    • pp.350-355
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    • 2009
  • Although previous studies on hexokinase (HK) II indicate both the N- and C-terminal halves are catalytically active, we show in this study the N-terminal half is significantly more catalytic than the C-terminal half in addition to having a significantly higher $K_m$ for ATP and Glu. Furthermore, truncated forms of intact HK II lacking its first N-terminal 18 amino acids ($\Delta$18) and a truncated N-terminal half lacking its first 18 amino acids ($\Delta$18N) have higher catalytic activity than other mutants tested. Similar results were obtained by PET-scan analysis using $^{18}F-FDG$. Our results collectively suggest that each domain of HK II possesses enzyme activity, unlike HK I, with the N-terminal half showing higher enzyme activity than the C-terminal half.