• YAKHAK HOEJI
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• v.35 no.5
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• pp.416-426
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• 1991

The effects of an irreversible or a reversible $\alpha_1$-adrenoceptor antagonist (dibenamine or prazosin) on $\alpha_1$-adrenoceptor-mediated vasoconstrictions were studied in the endothelium-denuded rat aorta. In these experiments, the mobilization of intracelluier calcium and translocation of extracellular calcium were also studied. To exclude the modulation of endothelium releasing EDRF and EDCF, the endothelium was removed in all rat aortas. Contraction induced by phenylephrine (a full $\alpha_1$-adrenoceptor agonist) was separated into a fast phasic component of the response due to the release of intracellular calcium and a slow tonic one due to the influx of extracellular calcium. Pretreatments with increasing doses of reversible $\alpha_1$-adrenoceptor antagonist prazosin, as well as irreversible $\alpha_1$-adrenoceptor antagonist dibenamine, inhibited the phasic component of phenylephrine-induced contraction more effectively than the tonic one. Pretreatment of dibenamine (0.2 $\mu{M}$) or prazosin (10 nM) to the rat aorta abolished phasic response but remained tonic one about 41% and 51%, respectively. These results suggest that as the efficiency of phenylephrine was progressively reduced by pretreatments with increasing doses of an irreversible or a reversible $\alpha_1$-adrenoceptor antagonist (dibenamine or prazosin), the contraction induced by phenylephrine became progressively more dependent on the influx of extracellular calcium.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1073-1079
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• 2004

Interactions of the cell adhesion molecules are known to play important roles in mediating inflammation. The proinflammatory cytokine, tumor necrosis factor-${\alpha}$(TNF-${\alpha}$), activates the NF-kB signaling pathway, which induces the expression of various genes, such as intercellular adhesion molecule-1 (ICAM-1). In this study, the effect of vitamin C on the ICAM-1 expression induced by TNF-${\alpha}$ in a human neuroblastoma cell line, SK-N-SH was investigated. Treatment with vitamin C resulted in the downregulation of the TNF-${\alpha}$-induced surface expression and ICAM-1 mRNA levels in a concentration-dependent manner. Moreover, a gel shift analysis indicated that vitamin C dose-dependently inhibited the NF-kB activation and IkB${\alpha}$ degradation induced by TNF-${\alpha}$. Taken together, these results suggest that vitamin C downregulates TNF-${\alpha}$- induced ICAM-1 expression via the inhibition of NF-kB activation.

• Korean Journal of Environmental Agriculture
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• v.22 no.4
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• pp.290-293
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• 2003

To measure an effects of strontium on secretion of ${\alpha}$-amylase and RNase, wheat aleurone layers were isolated after the pre-incubation in a solution with or without 10 mM $SrCl_2$ or $CaCl_2$ for 3 days at $25^{\circ}C$ in the dark under aseptic conditions. The secretion of ${\alpha}$-amylase reached a maximum at 72 h after incubation. $Sr^{2+}$ induced more effectively secretion of ${\alpha}$-amylase than $Ca^{2+}$. The ${\alpha}$-amylase secretions by $Sr^{2+}$ or $Ca^{2+}$ ware about $2 (Ca^{2+})$ to $2.5 (Sr^{2+})$ fold higher than it without divalent ions, When aleurone layers were incubated without divalent ions, however, the ${\alpha}$-amylase was remarkably retained in the tissues. Total ${\alpha}$-amylase synthesis (ie. tissues + media) was slightly lowered by 10mM $SrCl_2$ addition. It seemed that the RNase secretion begins at 18 h after incubation. This meaned that the RNase secretion may process slower than ${\alpha}$-amylasee secretion. $Ca^{2+}$ effect on RNase secretion is stronger than $Sr^{2+}$ unlikely to ${\alpha}$-amylase. The secretion process is likely to be suddenly induced between 72 hand 96 h. These results suggested that the secretion was enhanced after the accumulation in aleurone layers.

• Journal of Chest Surgery
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• v.22 no.3
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• pp.402-415
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• 1989

Extracorporeal circulation leads to functional disorder and structural damage of organs, especially hematologic and pulmonary system, mainly by sequestration of neutrophils and deposition of macrophages at lung. Then, proteases are secreted, which insult vascular basement membrane of pulmonary capillary and alveolar septa of the lung. Among these, the most important protease at lung is elastase, because major component of lung is elastin. For prevention of lung injury, inactivators or antidotes to elastase should be necessary and Alpha 1-Proteinase Inhibitor is the elastase inactivator. Clinical experimental study was carried out to investigate the immediate postoperative change of serum Alpha 1-PI level following cardiopulmonary bypass for 20 heart cases [congenital 16 cases, acquired 4 cases] and 10 control [subtotal gastrectomy] cases. Also preliminary study was performed for 31 cases of open heart patients. The results were as follows: l. Immediate postoperative serum levels of Alpha 1-PI was significantly decreased at open heart surgery group [P< 0.005], but not decreased at control group. 2. There were no significant difference in change of serum Alpha 1-PI level between and membrane and bubble oxygenator group.Z 3. There were no significant difference in changes of serum Alpha 1-PI level between CHD and AHD. Alpha 1-PI is consumed at lung during cardiopulmonary bypass and increase after operation compensatedly and protect multiple organic damage especially lung. Therefore, Alpha 1-PI can be indicator for evaluation of prevention and treatment of pump-lung syndrome.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.462-462
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• 2012

수문 분석과 갈수기 유량 산정, 가뭄관리에 직접/기저 유출 분리 및 평가는 매우 중요하며, 이러한 분석을 위하여 많은 모형들이 개발되었고, 실제 유역에 적용되어 연구에 이용되고 있다. 이들 중 Baseflow filter program(BFlow)을 이용한 감수곡선의 Alpha factor 산정 방법이 직접/기저 유출 분리에 널리 이용되고 있다. 하지만 BFlow는 장기 유량 자료를 이용하여 그 유역을 대표할 수 있는 Alpha factor 만을 제시하고 있기 때문에, 계절별/연별로 변화하는 감수곡선의 특성을 정확히 반영하기에는 많은 단점이 있다. 따라서 본 연구에서는 계절별로 변화하는 감수곡선 특성을 조금 더 정확하게 실제 유역에 적용하기 위하여 BFlow 프로그램이용, 장기간의 유량 특성을 분석하여 계절별 Alpha factor를 산정하고 이를 Soil and Water Assessment Tool(SWAT) 모형에 적용하여 기존의 방법과의 차이를 분석하였다. SWAT 모형의 경우 alpha factor가 실제로는 Hydrologic Response Unit (HRU) 별로 활용되기 때문에, 계절별 Alpha factor 산정이 미치는 영향이 실제로 다소 크게 분석되었다. 특히 본 연구에서는 저유량 부분의 차이를 면밀히 분석하여 Alpha factor 저유량 산정에 미치는 영향을 파악하고자 하였으며 이는 SWAT 모형의 단점인 저유량 산정을 개선하는데 기여할 수 있으리라 판단된다.

• Bulletin of the Korean Chemical Society
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• v.15 no.10
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• pp.832-835
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• 1994

The ${alpha}$-amylase gene of Bacillus licheniformis has been cloned and two mutant ${alpha}$-amylase genes of which histidine 235 was changed to glutamine (H235Q) and aspartic acid 328 to glutamic acid (D328E) have been produced by site-directed mutagenesis. The kinetic parameters, optimum pH and thermostability of wild type(WT) and these two mutant amylases expressed in E. coli MC1061 have been compared after purification. The $K_m$ values of WT, H235Q and D328E ${alpha}$-amylases were 0.22%, 0.73%, and 0.80% respectively, when using starch as the substrate. The $V_max$ values of wild type ${alpha}$ -amylase and mutant ${alpha}$-amylases were 0.6-0.7%/minute, and did not show any significant differences among them. The optimum pH of D328E ${alpha}$-amylase was shifted to more acidic pH. Also, the thermostability of H235Q ${alpha}$-amylase was increased compared to the wild type ${alpha}$-amylase.

• Journal of the Korean Magnetic Resonance Society
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• v.23 no.1
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• pp.26-32
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• 2019

${\alpha}B$-crystallin (${\alpha}BC$) is a member of a small heat-shock protein (sHSP) superfamily and plays a predominant role in cellular protein homeostasis network by rescuing misfolded proteins from irreversible aggregation. ${\alpha}BC$ assembles into dynamic and polydisperse high molecular weight complexes containing 12 to 48 monomers; this variable stereochemistry of ${\alpha}BC$ has been linked to quaternary subunit exchange and its chaperone activity. The chaperone activity of ${\alpha}BC$ poses great potential as therapeutic agents for various neurodegenerative diseases. In this mini-review, we briefly outline the recent advancement in structural characterization of ${\alpha}BCs$ and its potential role to inhibit protein misfolding and aggregation in various human diseases. In particular, nuclear magnetic resonance (NMR) spectroscopy and its complimentary techniques have contributed much to elucidate highly-dynamic nature of ${\alpha}BCs$, among which notable advancements are discussed in detail. We highlight the importance of resolving the structural details of various ${\alpha}BC$ oligomers, their quaternary dynamics, and structural heterogeneity.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.188-191
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• 1993

The reaction between methyl 2,3-di-O-benzyl-4,6-di-O-mesyl-${\alpha}$-D-glucopyranoside (1b) and potassium superoxide resulted in hydrolysis, and gave methyl 2,3-di-O-benzyl-${\alpha}$-D-glucopyranoside (1) as a sole product. When the reaction was performed with a vicinal dimesylate, methyl 4,6-O-benzylidene-2,3-di-O-mesyl-${\alpha}$-D-altropyranoside (4b), again the hydrolysis product, methyl 4,6-O-benzylidene-${\alpha}$-D-altropyranoside (4) was obtained. However, the reaction of potassium superoxide with another vicinal dimesylate, methyl 4,6-O-benzylidene-2,3-di-O-mesyl-${\alpha}$-D-glucopyranoside (3b), nucleophilic displacement took place to afford methyl 4,6-O-benzylidene-${\alpha}$-D-altropyranoside (4). Apparently different results from two trans vicinal dimesylates, 3b and 4b are explained by the transient formation of epoxides, methyl 2,3-anhydro-4,6-O-benzylidene-${\alpha}$-D-allopyranoside (8) and methyl 2,3-anhydro-4,6-O-benzylidene-${\alpha}$-D-mannopyranoside (9) by $KO_2$. The reaction between the allo epoxide 8 and $KO_2$ gave altro 4. The manno epoxide 9 also afforded altro 4 as the major product. Facile epoxide formation by the reaction of a vicinal dimesylate and superoxide was also observed with 3-O-benzyl-1,2-O-isopropylidene-5,6-di-O-mesyl-${\alpha}$-D-glucofuranose: 5,6-anhydro-3-O-benzyl-1,2-O-isopropylidene-${\beta}$-L-idofuranose was obtained.

• Tuberculosis and Respiratory Diseases
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• v.54 no.4
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• pp.449-458
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• 2003

Background : Cyclosporin A(CsA) and tacrolimus(FK506) have been widely used as immunosuppressants. The effects of CsA, or FK506, on the $I{\kappa}B/NF-{\kappa}B$ pathway have been shown to vary according to the cell type. However, their effects on the $I{\kappa}B/NF-{\kappa}B$ pathway have not been reported in bronchial epithelial cells. In this study, the effects of CsA and FK506 on the $I{\kappa}B/NF-{\kappa}B$ pathway in bronchial epithelial cells, monocytes, lymphocytes and alveolar macrophages were evaluated. The relationship between their effects on the $I{\kappa}B/NF-{\kappa}B$ pathway and $I{\kappa}B$ kinase(IKK) activity was also investigated. Methods : BEAS-2B and A549 cells, pulmonary alveolar macrophages, peripheral blood monocytes and lymphocytes were used. The cells were pre-treated with CsA, or FK506, for various time periods, followed by stimulation with TNF-${\alpha}$, LPS or IL-$1{\beta}$. The $I{\kappa}B{\alpha}$ expressions were assayed by Western blot analyses. The IKK activity was evaluated by an in vitro immune complex kinase assay, using GST-$I{\kappa}B{\alpha}$ as the substrate. Results : Neither CsA nor FK506 affected the level of $I{\kappa}B{\alpha}$ expression in any of the cell types used in this study. CsA pre-treatment inhibited the TNF ${\alpha}$-induced $I{\kappa}B{\alpha}$ degradation in bronchial epithelial cells. In contrast, the TNF ${\alpha}$-induced $I{\kappa}B{\alpha}$ degradation was not affected by FK506 pre-treatment. However, FK506 suppressed the cytokine-induced $I{\kappa}B{\alpha}$ degradation in the pulmonary alveolar macrophages, peripheral blood monocytes and lymphocytes. The inhibitory effect of CsA, or FK506, on $I{\kappa}B{\alpha}$ degradation was not related to IKK. Conclusions : CsA and FK506 suppressed the $I{\kappa}B{\alpha}$ degradation in bronchial epithelial cells, monocytes, lymphocytes and alveolar macrophages, so this may not be mediated through IKK.

• Clinical and Experimental Pediatrics
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• v.52 no.4
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• pp.476-480
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• 2009

Purpose : The purpose of this study was to investigate the polymorphisms of the TNF-alpha promotor gene, its susceptibility to Kawasaki disease (KD) and to assess whether the TNF-alpha promotor gene polymorphism was related the risk of coronary artery lesions (CALs). Methods : From January 2003 to January 2007, 51 children (30 boys and 21 girls) with KD and 48 children forming an age-matched control group were studied. DNA from the peripheral blood of all the children was sampled, and the DNA polymorphisms of the 5' flanking regions of the TNF-alpha promoter gene at position -308 [guanine (G) to adenine (A)] were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Then, the relationship between KD and the TNF-alpha promotor gene polymorphisms was evaluated. Results : The A allele frequency of the -308 site of the TNF-alpha promotor gene was 17.6% (9/51) for children with KD and 6.8% (3/48) for the control group children, but this result was not statistically significant. Twenty-four patients experienced CALs within 60 days after the onset of symptoms. KD children with TNF-alpha -308 A allele had lower frequencies of CALs (12.5% versus 22.2%, P>0.05). Conclusion : The DNA polymorphism of the -308 site TNF-alpha gene was not associated with susceptibility to KD and a risk of CALs. Multicenter, large-scale randomized controlled trials are needed for further study.