• Toxicological Research
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• 제29권1호
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• pp.21-25
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• 2013

The selective targeting of an integrin ${\alpha}_v{\beta}_3$ receptor using radioligands may enable the assessment of angiogenesis and integrin ${\alpha}_v{\beta}_3$ receptor status in tumors. The aim of this research was to label a peptidomimetic integrin ${\alpha}_v{\beta}_3$ antagonist (PIA) with $^{99m}Tc(CO)_3$ and to test its receptor targeting properties in nude mice bearing receptor-positive tumors. PIA was reacted with tris-succinimidyl aminotriacetate (TSAT) (20 mM) as a PIA per TSAT. The product, PIA-aminodiacetic acid (ADA), was radiolabeled with $[^{99m}Tc(CO)_3(H_2O)_3]^{+1}$, and purified sequentially on a Sep-Pak C-18 cartridge followed by a Sep-Pak QMA anion exchange cartridge. Using gradient C-18 reverse-phase HPLC, the radiochemical purity of $^{99m}Tc(CO)_3$-ADA-PIA (retention time, 10.5 min) was confirmed to be > 95%. Biodistribution analysis was performed in nude mice (n = 5 per time point) bearing receptor-positive M21 human melanoma xenografts. The mice were administered $^{99m}Tc(CO)_3$-ADA-PIA intravenously. The animals were euthanized at 0.33, 1, and 2 hr after injection for the biodistribution study. A separate group of mice were also co-injected with 200 ${\mu}g$ of PIA and euthanized at 1 hr to quantify tumor uptake. $^{99m}Tc(CO)_3$-ADA-PIA was stable in phosphate buffer for 21 hr, but at 3 and 6 hr, 7.9 and 11.5% of the radioactivity was lost as histidine, respectively. In tumor bearing mice, $^{99m}Tc(CO)_3$-ADA-PIA accumulated rapidly in a receptor-positive tumor with a peak uptake at 20 min, and rapid clearance from blood occurring primarily through the hepatobiliary system. At 20 min, the tumor-to-blood ratio was 1.8. At 1 hr, the tumor uptake was 0.47% injected dose (ID)/g, but decreased to 0.12% ID/g when co-injected with an excess amount of PIA, indicating that accumulation was receptor mediated. These results demonstrate successful $^{99m}TC$ labeling of a peptidomimetic integrin antagonist that accumulated in a tumor via receptor-specific binding. However, tumor uptake was very low because of low blood concentrations that likely resulted from rapid uptake of the agent into the hepatobiliary system. This study suggests that for $^{99m}Tc(CO)_3$-ADA-PIA to be useful as a tumor detection agent, it will be necessary to improve receptor binding affinity and increase the hydrophilicity of the product to minimize rapid hepatobiliary uptake.

• 미생물학회지
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• 제33권4호
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• pp.257-261
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• 1997

겨울철 소양호에서 세균 군집 구조를 파악하고자 총세균수와 EUB338, ALF1b, BET4a, GAM42a와 CF probe 등 fluorescent rRNA targeted oligonucleotide probe 와 반응하는 세균 개체수를 수심별로 측정하였다. 총세균수는 $0.7{\times}10^6{\sim}1.1{\times}10^6cell{\cdot}ml^{-1}$이였으며, 5 m와 10 m 수층에서 높게 나타났다. 총세균수에 대한 Eubacteria의 비율은 34~90%이였으며, 5 m와 10 m에서 낮게 나타났다. Proteobacteria ${\alpha}$-group은 Eubacteria의 10.8-28.7%, ${\beta}$-group은 4.5-53.5%, ${\gamma}$-group은 4.9-35.5%, 그리고 Cytophaga-Flavobacterium group은 6.1-21.1%이였다. 0-5 m 수심에서는 ${\beta}$-group이 28.6-53.5%로 우점하고 있었으며, 10 m에서는 ${\gamma}$-group이 35.5%로 우점하였다. 30, 50 m 수심에서는 ${\alpha}$-group과 Cytophaga-Flavobacterium group이 우점하였다. 세균 군집 구조로 보면 0-2 m, 5-10 m 그리고 30-50 m의 3개층은 각각 독특한 특징을 나타내었다. 이 방법으로 호수 생태계에 대한 새로운 정보를 얻을 수 있었다.

• 한국지반공학회논문집
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• 제22권11호
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• pp.47-54
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• 2006

비고결화된 흙의 전단파 속도는 모세관 현상을 무시할 수 있는 경우 유효응력의 함수로 표현할 수 있다. 그러나 지반에서의 응력상태는 등방성인 경우보다는 이방성인 경우가 대부분이므로 이러한 유효응력은 파가 전파되는 방향과 입자가 움직이는 방향의 두 가지로 나눠진다. 또한, 전단파 속도는 입자 특성에 따라 실험적으로 결정되는 ${\alpha}$계수와 ${\beta}$지수에 영향을 받는데 ${\beta}$지수의 경우 입상 매질(particulate material)의 접촉 특성(입자크기, 입자모양, 입자들의 구조)에 따라 결정되며, ${\alpha}$계수는 패킹(packing)의 형태(즉, 간극률과 coordination number), 입자를 만드는 재료의 특성, 입자간의 접촉 거동, 구조의 변화에 따라서 변화한다. 본 연구에서는 입자구조의 특성이 다른 점토, 모래, mica등의 재료로 압밀시험을 실시하고 벤더 엘리먼트를 통하여 유효응력 방향과 입자 이방성에 따른 전단파 속도를 측정하였다. 연구 결과, 둥근 입자로써 입자자체가 등방성인 경우에는 응력이방성에 의하여 전단파 속도의 크기가 달라지는 것으로 나타났다. 또한 전단파 속도는 동일한 응력 하에서 입자 배열에 의존하는 것으로 나타났다. 이번 연구는 지반구조물의 설계와 시공 시 전단파 속도와 전단탄성계수는 매우 신중하게 계산되고 사용되어져야 함을 제시하고 있다.

• 한국세라믹학회지
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• 제35권4호
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• pp.413-419
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• 1998

${\beta}$-silicon carbides with yttrium aluminum garnet of 2,5,10 mol% were prepared by a liquid--phase sint-ering and the microstructural evolution and phase transformation were investigated during sintering as functions of liquid-phase amount and sintering time. The rate of grain growth decreases with the addition of the amount of yttrium aluminum garnet (YAG) in the SiC starting powder however the apparent density and the aspect ratio of grains in sintered body increase. The phase transformation from ${\beta}$-SiC to ${\alpha}$-SiC were dependent on the liquid-phase amount and sintering time.

• 한국미생물·생명공학회지
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• 제21권2호
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• pp.119-124
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• 1993

An alkalophilic microorganism for overproduction of cyclodextrin glucanotransferase (CGTase) was newly isolated from hot-water spring soil, and identified as Bacillus firmus var. alkalophilus H609. The strain maintained stability during preservation and cultivation for the enzyme production, and produced significant amount of CGTase corresponding to the volumetric activity of 75 units/mL at 37C, initial pH of 11.2, and after 40 hours. The strain excreted several different proteins showing CGTase activity that catalyzed the formation of mainly beta-and Gamma-type cyclodextrin (ratio of 7:1) from soluble starch without accumulation of alpha-type. Other enzymatic properties were also investigated.

• 한국세라믹학회지
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• 제21권1호
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• pp.11-18
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• 1984

$eta$-Sialon synthesis was investigated via the simultaneous reduction and nitridation of Hadong Pink Kaolin using the graphite as a reducing agent at 135$0^{\circ}C$ under 80% $N_2-20%H_2$ atmosphere. When Hadong Pink Kaolin-graphite-silicon nitride seed(molar ratio ; $SiO_2:C:Si_3N_4$=1;3.5:0.05) mixture was heated at 135$0^{\circ}C$ for as long as 20h in 80%$N_2-20%H_2$ atmosphere a homogeneous $eta$-Sialon$(Si_{3.5}Al_{2.5}O_{2.5}N_{2.5})$ was mainly formed together with a small amount of $\alpha$-$Si_3N_4$.

• Journal of Pharmaceutical Investigation
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• 제15권3호
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• pp.100-112
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• 1985

Dissolution characteristics of flurbiprofen solvent deposited on ${\alpha}-cyclodextrin$, ${\beta}-cyclodextrin$, lactose and corn starch were studied to evaluate the pharmaceutical aspects of solvent deposition method where drug was solvent deposited on the surface of excipients. In a solvent deposition system, the drug to excipient ratio and kind of excipient affect much on dissolution rates of flurbiprofen. The solvent deposition system formation was confirmed by scanning electron microscope. By increasing the amounts of matrix, it was possible to enhance the dissolution rate of flurbiprofen solvent deposition system. The amount of flurbiprofen dissolved from ${\beta}-cyclodextrin$ deposition system (1:10) at 60 minutes was enhanced 6.5 times in water and 28 times in simulated gastric juice compared with flurbiprofen alone. Flurbiprofen solvent deposited system (1:10) enhanced dissolution rate greater than inclusion complex and dispersion system.

• 한방재활의학과학회지
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• 제15권1호
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• pp.99-108
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• 2005

Objectives : Patrinia scabiosaefolia (PS) has long been as a remedy for treating infectious diseases in Korea. In the present experiments, the author examined the effects of PS on the cholecystokinin-octapeptide (CCK)-induced pancreatitis (AP) in rats. Methods : Male Wister rats weighing 200 to 250 g were divided into two group. Normal untreated group, in treatment with PS group; PS was administered orally, followed by $75{\mu}g/kg$ CCK subcutaneously three times, after 1, 3 and 5 h. This whole procedure was repeated for 5 days. In treatment with saline group, the protocol was the same as in treatment group with PS. The author determined the pancreatic weight/body weight ratio, the levels of pancreatic heat shock proteins(HSP)60, HSP72 and the secretion of pro-inflammatory cytokines. Results and Conclusion : PS was significantly decreased the pancreatic weight/body weight ratio in CCK-induced AP. PS increased HSP60 and HSP72 compared with CCK-induced AP. Additionally, the secretion of tumor necrosis factor(TNF)-${\alpha}$, interleukin(IL)-$1{\beta}$ and IL-6 the levels of amylase and lipase were lower than that of saline. These results suggest that PS may has a inhibitory effect against CCK-induced AP.

• 한국전기전자재료학회논문지
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• 제22권11호
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• pp.941-948
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• 2009

The present study aims at the examination of the effects of 1 mol% NiO addition on the reaction, microstructure development, resultant electrical properties, and especially the bulk trap and interface state levels of $ZnO-Bi_2O_3-Sb_2O_3$ (Sb/Bi=0.5, 1.0, and 2.0) systems (ZBS). The samples were prepared by conventional ceramic process, and characterized by density, XRD, SEM, I-V, impedance and modulus spectroscopy (IS & MS) measurement. The sintering and electrical properties of Ni-doped ZBS (ZBSN) systems were controlled by Sb/Bi ratio. Pyrochlore ($Zn_2Bi_3Sb_3O_{14}$) was decomposed more than $100^{\circ}C$ lowered in ZBS (Sb/Bi=1.0) by Ni doping. The reproduction of pyrochlore was suppressed by the addition of Ni in ZBS. Between two polymorphs of $Zn_7Sb_2O_{12}$ spinel ($\alpha$ and $\beta$), microstructure of ZBSN (Sb/Bi=0.5) composed of a-spinel was more homogeneous than $Sb/Bi{\geq}1.0$ composed of $\beta$-spinel phase. In ZBSN, the varistor characteristics were not improved drastically (non-linear coefficient $\alpha\;=\;6{\sim}11$) and independent on microstructure according to Sb/Bi ratio. Doping of Ni to ZBS seemed to form ${V_0}^{\cdot}$ (0.33 eV) as dominant bulk defect. From IS & MS, especially the grain boundaries of Sb/Bi=0.5 systems were divided into two types, i.e. sensitive to oxygen and thus electrically active one and electrically inactive intergranular one with temperature.

• 대한한방소아과학회지
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• 제20권3호
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• pp.117-127
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• 2006

Objectives : In this study, we investigated the effects of Daehwangmokdanpitang-gagambang(DMG) on treatment for cholecystokinin-octapeptide(CCK)-induced acute pancreatitis(AP) in rats. Methods : Male Wistar rats weighing 200 to 250 g were divided into three groups. The first was normal untreated group, the second was in treatment with DMG group; DMG was administered orally, followed by 75 ${\mu}g/kg$ CCK subcutaneously three times, after 1, 3 and 5 h. This whole procedure was repeated for 5 days. The third was in treatment with saline group, the protocol was the same as in treatment group with DMG. We determined the pancreatic weight/body weight ratio, the levels of pancreatic HSP60, HSP72, ERK, p38 MAPK and the secretion of pro-inflammatory cytokines. Repeated CCK treatment resulted in the typical laboratory and morphological changes of experimentally induced pancreatitis. Results : DMG was significantly decreased the pancreatic weight/body weight ratio in CCKinduced AP and DMG increased HSP60 and HSP72 compared with CCK-induced AP. DMG suppressed ERK and p38 MAPK activation. Additionally, the secretion of $IL-1{\beta}$ and $TNF-{\alpha}$ and the levels of amylase and lipase were lower than that saline. Conclusions : DMG has an effect to treatment for CCK-induced AP.