• The Korean Journal of Pharmacology
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• v.32 no.1
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• pp.23-29
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• 1996

According to the traditional receptor model, competitive antagonists share with agonists the ability to bind to a common site on receptors, but they are different from agonist in that they cannot trigger the biological response-i.e., they lack intrinsic efficacy. Recent findings extend the model by indicating that not all antagonists display an intrinsic efficacy of zero but that some display 'inverse agonism'. In the present study we studied the inverse agonism at $A_1$ adenosine receptors in membranes prepared from rat cerebral cortex. Eight commercially available $A_1$ adenosine receptor antagonists (CGS-15943, ADPX, CPT, DPCPX, DPX, N-0840, PACPX and 8-PT) were screened for inverse agonism by measuring the extent of $[^{35}S]guanosine-5'-({\gamma}-thio)$ triphosphate $([^{35}S]GTP_{\gamma}S)$ binding to G proteins. The agonist-induced stimulation of $[^{35}S]GTP_{\gamma}S$ bindings was completely blocked in the presence of $A_1$ adenosine receptor antagonists. Under optimal conditions, two types of antagonists could be distinguished. Seven antagonists including DPCPX decreased the basal $[^{35}S]GTP_{\gamma}S$ binding in the absence of agonist, displaying inverse agonist activity. One (CGS-15943) had no effect on the basal bindings. N-ethylmaleimide treatment reduced the basal bindings as well as agonist-mediated stimulation of $[^{35}S]GTP_{\gamma}S$ bindings, indicating that a substantial amount of this binding reflects an activated state of the C proteins. In good agreement with these findings, 0.1 mM GTP decreased the apparent affinity of the receptors for the agonist PIA, increased that for DPCPX, and had no effect on that for CGS-15943.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.1
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• pp.43-52
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• 2006

Topical fluoride application for children is a widely peformed procedure in the field of pediatric dentistry to prevent dental caries. However, it is recently recognized as having some unwanted effects on several esthetic restorative materials as it roughens the surface of the restorative materials. The aim of this study was to evaluate the surface changes in composite resins to topical fluoride. Composite resins(Z $250^{(R)}$, Ultraseal $XT^{(R)}$ Filtek $flow^{(R)}$ $Revolution^{(R)}$, $Denfil^{(R)}$) in topical fluoride agents were immersed and their surface roughness, weight loss and SEM were evaluated. The results were as follows : 1. The 4 minutes-immersion groups showed more roughened surface than 1 minute-immersion groups and the control groups showed the smoothest surface among all the materials, and there was statistically significant difference except the revolution between the groups. 2. There was no significant difference between the 1 minute-immersion groups and 4 minutes-immersion groups in weight loss. 3. The experimental group treated with topical fluoride gel showed the generally mere roughened surface than control group in the SEM findings.

• Fire Science and Engineering
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• v.24 no.4
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• pp.12-17
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• 2010

The purpose of this study is to determine how effectively waste tire recycled material mixed with flame retardant work in combating fire. As discovered in the previous study, waste tire mixed with cement mortar has more insulation capacity. However, this mortar is weak against fire. Therefore flame retardant, with a specific proportional mix, will be added to increase its fire prevention capacity. Tests will be made in accordance with ISO 5657 procedures for measuring fire ignition time, flame and shape variation of test pieces at the Building Material Test Institute. The test piece will be set up with horizontal levels having a constant radiation heat of $1{\sim}5W/cm^2$. Temperature transfers and increases from the surface into the interior. Combustible gases result due to pyrolysis, and regular contact is maintained between the fire source and the center of the test piece for assessment purposes. Ignition has not been occurred without adding retardant meaning that there is almost no possibility of ignition of waste tire particle. This fact can be considered as fire load to appreciate a volume of combustion materials. Flame is not occurred due to heat-absorbing effect by adding non-organic series retardant into waste tire particle. Conclusions have been summarized as follows; 1) Combustion of building material can be decreased by adding retardant to waste tire-mixing mortar. But compressive strength and insulation capacity of the material should be measured later. 2) Firing prevention and ignition are main points of building fire. Reasonable fire engineering assessment of interior material should be made for establishing effective disaster prevention system.

• Journal of the Korean Chemical Society
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• v.54 no.2
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• pp.198-207
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• 2010

The construction and performance characteristics of doxepin hydrochloride selective electrodes were developed. Three types of electrodes: plastic membrane I, coated wire II, and coated graphite rod III were constructed based on the incorporation of doxepin hydrochloride with ammonium reineckate. The influence of membrane composition, kind of plasticizer, pH of the test solution, soaking time, and foreign ions on the electrodes was investigated. The electrodes showed a Nernstain response with a mean slope of 57.41 ${\pm}$ 0.5, 56.22 ${\pm}$ 0.2 and 52.88 ${\pm}$ 0.7 mV at $25^{\circ}C$ for electrode I, II and III respectively, over Doxepin hydrochloride concentration range from $1{\times}10^{-2}-1{\times}10^{-6}M$, $5{\tims}10^{-2}-1{\times}10^{-6}M$ and $1{\times}10^{-3}-5{\times}10^{-6}M$, and with a detection limit $5.0{\times}10^{-7}M$, $6.3{\times}10^{-7}M$ and $2.5{\times}10^{-6}M$ for electrode I, II and III respectively. The constructed electrodes gave average selective precise and usable within the pH range 3 - 7. Interferences from common cations, alkaloids, sugars, amino acids and drug excipients were reported. The results obtained by the proposed electrodes were also applied successfully to the determination of the drug in pharmaceutical preparations and biological fluids.

• The Korean Journal of Archival Studies
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• no.14
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• pp.325-357
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• 2006

In diesem Aufsatz wird die Geschichte der Bewertungsdiskussion in Deutschland vorgestellt. Bis zum 18. Jh. war das Ziel der Archivarbeit die Systematisierung der rechtlichen und politischen Kenntnissen. Der juristisch geschulte Archivar hob Unterlagen in der Regel aus $Gr{\ddot{u}}nden$ der Rechtssicherheit auf. Vernichtet wurde, was schon seit $l{\ddot{a}}ngerem$ im Archiv lag. Nach dem Zusammenfall des alten Regimes haben die Archivare keine mehr mit dem Recht des Herrschers zu tun. Und die Archive wurden zu $Lagerst{\ddot{a}}tten$ der Geschichte und Forschung. $F{\ddot{u}}r$ den Ordnung der Archivgut, die aus den verschiedener Dienststellen stammten, wurde das Provenienzprinzip gebildet. Die Archivare richtete sich auf das inhaltsorientierten Bewertungsverfahren, das die wissenschaftlichen $Bed{\ddot{u}}rfnisse$ befriedigte. Der Anlass der Bildung der modernen Archivtheorie war der ersten Weltkrieg. Das Problem, wie man die Massenakten, die $W{\ddot{a}}hrend$ dieses Krieges entstanden, behandeln sollten, $f{\ddot{u}}hrte$ unter dem $Einflu{\ss}$ der Demokratie zur Bildung der Provenienz-orientierte Bewertungsdiskussion. Aufbau, Zielsetzung und Verfahren der aktenbildenden Stelle bildeten den Ausgang der Bewertung. Im Klima ${\ddot{o}}ffentlicher$ $B{\ddot{u}}rokratieablehnung$ der 50er und 60er Jahren wurde die inhaltsorientierte Auswahl wieder die vorherrschende Methodenvorgabe. Diese Theorie, die Booms vertritt, $f{\ddot{u}}hrt$ zu der Theorie der dokumentation strategy von Ende 20. Jh.

• Food Science and Industry
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• v.55 no.3
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• pp.276-283
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• 2022

Vitamin D is a fat-soluble vitamin helps to retain calcium and phosphorus but also has shown to affect immune regulation and homeostasis. In humans, vitamin D3 and vitamin D2 and their metabolite has intensively studied in both innate and adaptive immune system that they are important to regulate overwhelmed inflammation. The vitamin D receptor is a nuclear hormone receptor which regulate various downstream target gene expressions as a transcription factor related to metabolism, immune regulation, etc. Vitamin D deficiency is a high-risk factor for inflammatory diseases like autoimmune disease and allergy. In addition, reduced vitamin D seem to correlate with susceptibility to the virus infection such as HIV and COVID-19. In this review, we will summarize up-to-date vitamin D's role in various immune cells, immune regulatory functions during autoimmune, allergic, and infectious diseases. We will also discuss about vitamin D supplement effects in human trial studies for COVID-19.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.10
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• pp.1446-1451
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• 2010

Silk sericin protein was hydrolyzed by seven proteolytic enzymes to examine the effectiveness of the hydrolysates to bind iron. The amino acid nitrogen contents of hydrolysates by Flavourzyme were higher than the others enzymes, and its iron binding capacity showed dose-dependent increase. The bioavailability of iron binding peptide from sericin hydolysates was investigated in iron-deficient rats. Three-week-old male rats were fed iron-deficient diet for three weeks. Rats were divided into four groups (DD: no treated group on iron deficient diet, DD+HI: heme-iron treated group, DD+OI: sericin-Fe, and DD+II: inorganic iron ($FeSO_4$) treated group, and then iron supplemented by injection for one week. After oral administration for one week, the iron contents of serum and liver were significantly higher in DD+OI ($4.2\;{\mu}g/mL$ and $80.1\;{\mu}g/mL$) and DD+HI ($3.2\;{\mu}g/mL$ and $70.6\;{\mu}g/mL$) than DD ($2.0\;{\mu}g/mL$ and $47.9\;{\mu}g/mL$). Hemoglobin content of treated groups was significantly higher than DD, but the significant difference among groups was not shown. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels did not show any significant difference among all groups. Binding iron to peptide from sericin hydolysates seems to improve its bioavailability and to hasten the cure of iron deficiency in experimental rat.

• Tuberculosis and Respiratory Diseases
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• v.54 no.4
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• pp.439-448
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• 2003

Background : Surfactant protein B(SP-B) and surfactant protein C(SP-C) are important in accelerating surface spreading of surfactant phospholipid. The glucocorticoids accelerate the morphologic differentiation of epithelial cells into type II cells and increase the rate of phosphatidylcholine synthesis. The hydrophobic surfactant protein has been shown to be upregulated by glucocorticoids in vitro, however, its regulation in vivo is not well established. Methods : The authors investigated the effects of glucocorticoid on the accumulation of mRNA encoding SP-B and SP-C protein content of the lung. Adult rats were given different doses of subcutaneous dexamethasone and sacrificed at 24 hours and 1 week. SP-B and SP-C mRNA were measured by a filter hybridization method. Results : 1) The accumulation of SP-B mRNA at 24 hours after 0.2 mg/kg dexamethasone treatment was increased by 23.7%. 2) The accumulation of SP-B mRNA at 1 week after 2 mg/kg dexamethasone treatment was significantly increased by 96.6%(P<0.001). 3) The accumulation of SP-C mRNA at 24 hours after 0.2 mg/kg dexamethasone treatment was significantly increased by 42.7%(P<0.01). 4) The accumulation of SP-C mRNA at 1 week after 2 mg/kg dexamethasone treatment was significantly increased by 60.0% (P<0.01). Conclusion : The authors concluded that dexamethasone treatment in vivo resulted in increased levels of SP-B mRNA and SP-C mRNA. These results suggested that dexamethasone stimulates the synthesis of hydrophobic proteins associated with surfactant.