• Title/Summary/Keyword: MgB2

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Attenuation of Reperfusion Injury with Angiotension $AT_1$ Receptor Blockade in Rat Myocardial Ischemic Model (백서 심근 허혈 모델에서 angiotension $AT_1$수용체 차단제의 재관류 손상 감소 효과)

  • Choi, Jun-Young;Choi, Dong-Ju;Ahn, Hyuk
    • Journal of Chest Surgery
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    • v.34 no.3
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    • pp.203-211
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    • 2001
  • 배경: AT$_1$수용체의 길항제가 세포 수준에서 심근을 재관류 손사으로부터 보호할수 있다는 것으로 알려져 있지만, 생체내에서의 효과나 그 기전은 아직 명확히 밝혀지지 않았다. 본 연구에서는 백서 심근 허혈 모델을 이용하여, AT$_1$ 수용체의 길항제들 중 하나인 irbesartan이 심근이 재관휴 손상에 미치는 효과를 알아보고, 재관류 손상을 매개하는 한 각지 기전으로서 세포자멸의 기여에 대하여 연구하고자 하였다. 대상 및 방법: Sprague-Dawley 백서에서 무작용 부형약(10% gum arabic: 1군, 개체수=14관) irbesartan(50mg/kg/day :II 군, 개체수=12)을 각각 3일 동안 24시간마다 경구로 투여하였다. 실험동물의 좌 관상 동맥을 45분간 결찰하였다가, 그 후 2시간 동안 재관류시킨 다음 심장을 적출 하였다. TTC(triphenyltetrazolium chloride) 염색법을 이용하여, 허혈 노출 부위에 대한 심근 경색 부위의 비율을 측정하였다. Agarose gel 전기영동상의 DNa 분절 양상과 TUNEL(TdT-mediated dUCP nick end labeling) 염색을 관찰하여 세포자멸이 일어난 정도를 평가하였다. 세포자멸을 조절하는데 관여하는 것으로 알려진 Bcl-2(B-cell lymphoma 2 gene), Bad 등의 단백과 ERK (extracellular signal-regulated kinase), p-38 등 신호전달체계에 작용하는 MAPKs(mitogen-activated protein kinases)의 발현을 측정하기 위하여 Western blot을 시행하였다. 결과: 허혈 노출부위에 대한 심근 경색부위의 비율은 II군(42$\pm$2.7%)이 I군( 64.1$\pm$4.65)에 비해 유의하게 작았다.(p< 0.05), Agarose gel 전기영동상의 DNA laddering 양상은 I군에서 보다 높게 발현되었다. Bad와 ERK2의 발현은 두 군간에 유의한 차이가 없었다. 결론: AT$_1$수용체 길항제인 irbesartan은 생체에서 심근의 재관류 손상을 줄이는 효과가 있었다. 이 효과는 적어도 부분적으로 나만 심근세포의 세포자멸이 감소한 것에 기인한 것으로 설명할 수 있으며, 이 항-세포 자멸 효과는 Bcl-2의 발현증가와 관련이 있는 것으로 추정되었다.

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Preparation and Evaluation of a 4-Branched Polyethylene Glycol Derivative Modified with Exendin-4 and Stearylamine for Extended Hypoglycemic Action

  • Kim, In-Soo;Ma, Kyung-Wan;Bae, Sung-Ho;Yoon, Jeong-Hyun;Oh, Kyung-Taek;Lee, Eun-Seong;Lee, Don-Haeng;Lee, Kang-Choon;Youn, Yu-Seok
    • Journal of Pharmaceutical Investigation
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    • v.40 no.3
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    • pp.175-180
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    • 2010
  • Albumin-modification has been viewed as one of the most effective ways of extending the short in vivo lifetimes of peptide drugs by delaying glomerular filtration. In this study, we describe a new type 2 anti-diabetic exendin-4 (Ex4) peptide derivative with significant binding ability to human serum albumin (HSA). This exendin-4 derivative consists of a 4-branched polyethylene glycol $(PEG)_{5k}$ (Mw: 20 kDa) modified with three stearylamines ($C_{18}-NH_2$) and one exendin-4 on its branches. PEG and stearylamine were selected to provide functionality to increase molecular size and bind to albumin, respectively. This derivative ($3C_{18}-4PEG_{5k}$-Ex4) was shown to have larger molecular size (Ca. 152 kDa) than actual (25.0 kDa) when subjected to size-exclusion chromatography, and the fluorescein-tagged $3C_{18}-4PEG_{5k}$-Ex4 displayed significant binding to the HSA-immobilized Sepharose CL-4B resin using confocal laser scanning microscopy. Furthermore, $3C_{18}-4PEG_{5k}$-Ex4 was found to have acceptable anti-hyperglycemic efficacy via three consecutive oral glucose tolerance testings (OGTT) in fasted type 2 diabetic db/db mice. The $HD_{total}$ value ($57.6{\pm}12.3%$) of $3C_{18}-4PEG_{5k}$-Ex4 at a 50 nmol/kg dose was 2-fold greater than that ($31.0{\pm}8.7%$) of native exendin-4 in non-fasted db/db mice. Especially, the blood glucose levels in the mice group treated with $3C_{18}-4PEG_{5k}$-Ex4 did not rebound to ~150 mg/dL until 24 h after the injection, which obviously shows the extended hypoglycemia. We believe that this derivative has great pharmaceutical potential as a novel long-acting type 2 anti-diabetic injection treatment.

Regulation of Quinone Reductase Activity in Mice by Dehydroglyasperin C Isolated from Licorice (감초에서 분리된 데하드로글라이아스페린 C에 의한 마우스 모델계에서 quinone reductase 활성의 조절)

  • Han, Jung-Hwa;Kim, Jong-Sang
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.1
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    • pp.51-55
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    • 2013
  • Licorice, Glycyrrhizae radix, is one of the oldest and most frequently used botanicals in the oriental medicine. Our previous study showed that dehydrolyasperin C (DGC) isolated from licorice had antioxidant activity and induced phase 2 detoxifying enzymes in mouse hepatoma cells. Therefore, this study was conducted to investigate the effect of exposure time to DGC on quinone reductase (QR), one of the anticarcinogenic biomarkers, and antioxidant potential of plasma using animal model. ICR mice were divided into 7 groups, in which mice in each group were injected with DGC (5 mg/kg b.w.) for 0, 2, 4, 6, 8, 12, 24 hours respectively. Following the treatment the organs including liver, kidney, lung, stomach, large intestine, small and large intestines were collected and subjected to QR activity assay, western blotting, and FRAP assay. Exposure to DGC caused a significant induction of QR activity in stomach and large intestine of mice. Ferric reducing activity of plasma, a typical biomarker for antioxidative potentialshowed that DGC improved antioxidant potential in mice. However, no significant effect of DGC was observed in the other organs.

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Effects of Addition of Mugwort Powder on the Quality Characteristics of Emulsion-type Sausage (쑥 분말 첨가가 유화형 소시지의 품질특성에 미치는 영향)

  • Lee, J.R.;Hah, Y.J.;Lee, J.W.;Kim, K.S,;Lee, J.D.;Kim, K.S.;Lee, J.D.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.209-216
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    • 2004
  • This study was carried out to investigate the effects of addition of mugwort powder 0.7%, 10/0, 2%) on the quality characteristics of emulsion-type sausages. The pH, color, TBARS, textural properties, minerals content and sensory evaluation were evaluated. The pH values of sausage containing mugwort powder were significantly lower as compared to control during 20 days of storage, but there were higher than those of control at 40 days of storage. The $L^*$ and $a^*$ values of sausage containing mugwort powder were significantly lower as compared to control, but the $b^*$ values were significantly higher in the sausage containing mugwort powder. The TBARS values of sausage containing mugwort powder were significantly lower than those of control at 20 and 45 days of storage. The hardness values of sausage containing mugwort powder were significantly lower than those of control. The Na content of sausage containing mugwort powder were significantly lower as compared to control, but Mg, Ca, Mn and Fe contents were significantly higher in the sausage containing 2%l mugwort powder. Sensory panels evaluated that sausage containing mugwort powder had the higher preference scores in mugwort flavor.

Lead-free inorganic metal perovskites beyond photovoltaics: Photon, charged particles and neutron shielding applications

  • Srilakshmi Prabhu;Dhanya Y. Bharadwaj;S.G. Bubbly;S.B. Gudennavar
    • Nuclear Engineering and Technology
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    • v.55 no.3
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    • pp.1061-1070
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    • 2023
  • Over the last few years, lead-free inorganic metal perovskites have gained impressive ground in empowering satellites in space exploration owing to their material stability and performance evolution under extreme space environments. The present work has examined the versatility of eight such perovskites as space radiation shielding materials by computing their photon, charged particles and neutron interaction parameters. Photon interaction parameters were calculated for a wide energy range using PAGEX software. The ranges of heavy charged particles (H, He, C, N, O, Ne, Mg, Si and Fe ions) in these perovskites were estimated using SRIM software in the energy range 1 keV-10 GeV, and that of electrons was computed using ESTAR NIST software in the energy range 0.01 MeV-1 GeV. Further, the macroscopic fast neutron removal cross-sections were also calculated to estimate the neutron shielding efficiencies. The examined shielding parameters of the perovskites varied depending on the radiation type and energy. Among the selected perovskites, Cs2TiI6 and Ba2AgIO6 displayed superior photon attenuation properties. A 3.5 cm thick Ba2AgIO6-based shield could reduce the incident radiation intensity to half its initial value, a thickness even lesser than that of Pb-glass. Besides, CsSnBr3 and La0.8Ca0.2Ni0.5Ti0.5O3 displayed the highest and lowest range values, respectively, for all heavy charged particles. Ba2AgIO6 showed electron stopping power (on par with Kovar) better than that of other examined materials. Interestingly, La0.8Ca0.2Ni0.5Ti0.5O3 demonstrated neutron removal cross-section values greater than that of standard neutron shielding materials - aluminium and polyethylene. On the whole, the present study not only demonstrates the employment prospects of eco-friendly perovskites for shielding space radiations but also suggests future prospects for research in this direction.

Geochemistry of the Kwanaksan alkali feldspar granite: A-type granite\ulcorner (관악산 알칼리 장석 화강암의 지구화학 : A-형 화강암\ulcorner)

  • S-T.Kwon;K.B. Shin;H.K. Park;S.A. Mertzman
    • The Journal of the Petrological Society of Korea
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    • v.4 no.1
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    • pp.31-48
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    • 1995
  • The Jurassic Kwanaksan stock, so far known to be composed of biotite granite only, has the mineral assemblage of quartz+K-feldspar+plagioclase+biotite${\pm}$gernet. The lithology of the stock is classified as alkali feldspar granite by their mode and plagioclase compositions (An<5). Subsolvus feldspars, rather early crystallization of biotite, and shallow emplacement depth estimated from Q-Ab-Or diagram suggest hydrous nature of the magma, which contrasts with anhydrous A-type like geochemistry described below. Major and trace element compositions of the Kwanaksan stock are distinct from those of the adjacent Seoul batholith, suggesting a genetic difference between the two, The Kwanaksan stock shows geochemical characteristics similar to A-type granite in contrast to most other Mesozoic granites in Korea, in that it has high $SiO_2$(73~78wt%), $Na_2O+K_2O$, Ga(27~47 ppm). Nb(22~40 ppm), Y(48~95 ppm), Fe/Mg and Ga/Al, and low CaO(<0.51 wt%). Ba (8~75 ppm) and Sr(2~23 ppm). However, it has lower Zr and LREE and higher Rb(384~796 ppm) than typical A-type granite. LREE-depleted rare earth element pattern with strong negative Eu anomaly of previous studies is reinterpreted as representing source magma characteristics. The residual material during partial melting is not compatible with pyroxenes, amphibole or garnet, while significant amount of plagioclase is required. Similarity of geochemistry of the Kwanaksan stock to A-type granite suggests the origin of the stock has a chose relationship with that of A-type granite. These observations lead us to propose that the Kwanaksan stock was formed by partial melting of felsic source rock.

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Effect of Urushiol-Free Extracts from Fermented-Rhus verniciflua Stem Bark with Fomitella fraxinea on the Fermentation Characteristics of Doenjang (Soybean Paste) (장수버섯 배양법에 의해 urushiol이 제거된 발효옻 추출물이 된장발효에 미치는 영향)

  • Choi, Han-Seok;Jeong, Seok-Tae;Choi, Ji-Ho;Kang, Ji-Eun;Kim, Eugene;Noh, Jong-Min;Kim, Myung-Kon
    • The Korean Journal of Mycology
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    • v.40 no.4
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    • pp.244-253
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    • 2012
  • The effect of fermented Rhus verniciflua stem bark (FRVSB) extract on the microbial count, enzyme activity, concentrations of free amino acids and organic acids, and physiochemical properties of doenjang (soybean paste) was evaluated during brine fermentation. The FRVSB extract increased the total free amino acid concentration by 1.3-3.1-fold on the $42^{nd}$ day of brine fermentation. After the filtration of brine, the following microbial counts were obtained in the doenjang: bacteria, $0.3{\times}10^8-12.0{\times}10^8$ cfu/g; mold, $3.0{\times}10^4-21.0{\times}10^4$ cfu/g; yeast, $1.0{\times}10^4-2.0{\times}10^4$ cfu/g; Escherichia coli, not detected; and Bacillus cereus, $3.0{\times}10^2-25.0{\times}10^2$ cfu/g. The FRVSB extract addition enhanced the protein and starch degrading activity by 13.8-26.0% and 16.1-35.1%, respectively. The extract increased the total free amino acid content by 1.4-3.0-fold. Lactic acid, acetic acid, and pyroglutamic acid were the predominant organic acids in doenjang. Moreover, the proximate composition, pH, moisture, ash, salt, and amino nitrogen content were increased.

In Vitro/In Vivo Development after Thawing of Vitrified Mouse Blastocysts by Culture Condition and Embryo Transfer Method (초자화 동결된 생쥐 배반포기배의 융해 후 배양조건과 수정란 이식방법에 따른 체외/체내발달)

  • Kim, M.K.;Kim, E.Y.;Yi, B.K.;Yoon, S.H.;Park, S.P.;Chung, K.S.;Lim, J.H.
    • Clinical and Experimental Reproductive Medicine
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    • v.24 no.3
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    • pp.347-353
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    • 1997
  • This study was to test whether in vitro/in vivo survival of vitrified mouse blastocysts was influenced by culture conditions and ET method. Mouse blastocysts were obtained from in vitro fertilization and cultured for 4 days in M16 medium, and they were vitrified in EFS40 which contained 40% ethlyene glycol, 18% Ficoll and 0.5 mol sucrose in PBS. In experiment I, in vitro and in vivo survival rate of these embryos were evaluated in different culture condition after thawing. When thawed embryos were cultured in M16 medium as a control, m-CR1 medium contained 20 amino acids (2% BME amino acis and 1% MEM non-essential amino acids solution) and 4 mg/ml BSA and cumulus monolayer cell co-cultured condition in mCR1 medium (10% FBS), their in vitro survival at 24 hr after thawing was not affected by culture condition (75.6, 83.1, 82.4%). However, in vivo survival rates of implantation in m-CR1 medium (80.4%) were significantly higher than those of M16 medium (51.2%), co-culture (57.1%) condition, although there was no difference in live fetuses rates on day 15 gestation (39.0, 49.0, 38.1%). In experiment II, the in vivo development potential of embryos by ET methods was examined. When blastocysts were transferred to the day 2, 3 pseudopregnant recipient without culture soon after thawing, no pregnant recipient was obtained on the day 2 pseudopregnancy, and 50% of pregnancy rates and 15.4% of live fetus rates were obtained on the day 3 pseudopregnant recipients. These results were significantly lower than those of transferred group (day 3 pseudopregnant recipients) after culture for 16 hr post thawing (73.5, 57.1%) (p<0.05). In experiment III, to elevate usability of delayed embryos in vitro/in vivo survival of vitrified embryos (day 4 early, day 5 early and expanding blastocyst) were examined. in vivo survival rates (live fetus, total implantation) were higher in day 4 early blastocysts (33.3, 66.7%) than in day 5 expanding blastocysts (29.0, 38.7%), although the highest in vitro survival rates were obtained in the day 5 expanding brastocysts (78.3%). Therefore, these results suggest that the in vitro/in vivo survival rates of vitrified embryos could be improve by the culture condition and ET method and that the in vivo development rates of delayed embryos were decreased with longer culture duration in vitro. It means that more effective cryopreservation was obtained in day 4 early blastocysts than in day 5 expanding blastocysts.

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Anti-inflammation effect of blueberry (Vaccinium ashei) leaf extract on RAW 264.7 macrophages stimulated by lipopolysaccharide (Lipopolysaccharide에 의해 활성화된 RAW 264.7대식세포에서 블루베리 잎(Vaccinium ashei) 추출물의 항염증 효과)

  • Kim, Dong In;Kim, Hyun Jung;Yun, Jong Moon;Lee, Ji Hye;Han, So Jung;Kim, Ha Eun;Jang, Min Jung;An, Bong Jeun
    • Food Science and Preservation
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    • v.25 no.1
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    • pp.107-116
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    • 2018
  • The aim of this study is to investigate the antioxidant and intracellular anti-inflammatory efficacy of blueberry leaf extracted with hot water (BLW), 70% ethanol (BLE), and 70% acetone (BLA) in RAW 264.7 macrophages. In order to evaluate the anti-inflammatory effect of blueberry leaf extracts, RAW 264.7 macrophages were stimulated with lipopolysaccharide (LPS) to induce the production of inflammation-related factors, which were measure by Western blotting and real-time PCR methods. i-NOS, COX-2 protein, and mRNA expression showed concentration-dependent decrease. The decreases in the mRNA expression levels of interleukin-$1{\beta}$ (IL-$1{\beta}$), interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and prostaglandin $E_2$ ($PGE_2$) were concentration-dependent. Further, the antioxidant effects of blueberry leaf on total polyphenol contents, electron donating ability and $ABTS^+$ radical scavenging activity were evaluated. The total polyphenol contents of BLW, BLE, and BLA were $217.04{\pm}2.98$, $156.72{\pm}3.90$, and $182.88{\pm}3.02mg\;TAE/g$, respectively, while the electron donating abilities at $1,000{\mu}g/mL$ of BLW, BLE, and BLA were 81.7, 79.6, and 79.3%, respectively. The $ABTS^+$ radical scavenging activity was fond to be concentration dependent. The nitric oxide (NO) production inhibition activities at $50{\mu}g/mL$ of BLW, BLE, and BLA were 35.1, 42.4 and 42.7%, respectively. In conclusion, the antioxidant and anti-inflammatory test results indicate that blueberry leaf extracts (BLW, BLE, and BLA) can be used as potential anti-inflammatory agents.

The Influence of Pretreatment Period, 2-Hydroxynicotinic Acid and Anther Co-pretreatment on Embryo Induction in Isolated Microspore Culture of Capsicum annuum L. (고추의 나출 소포자 배양시 전처리 기간, 2-Hydroxynicotinic Acid 및 약-공동전처리가 소포자배 발생에 미치는 영향)

  • Park Eun-Joon;Kim Jin-Ae;Lee Jong-Suk;Jang In-Chang;Yoon Michung;Chung Sang-Ho;Kim Moonza
    • Journal of Plant Biotechnology
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    • v.32 no.1
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    • pp.37-44
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    • 2005
  • Microspores were isolated from pepper (Capsicum annuum L.) anthers by using a micro-blender and cultured in modified NLN medium at $25^{\circ}C$. The influence of pretreatment period at $32^{\circ}C$, adding the 2-hydroxynicotinic acid to a pretreatment medium, and co-pretreatment anthers with microscopes on the induction of embryo were examined. Globular and torpedo embryos were observed from 3 weeks after culture. Embryo development was not synchronized within culture. After 4 weeks in culture, in addition to globular and torpedo embryos, cotyledonary embryos were observed. Normal cotylodonary embryos developed into plantlets when transferred to a solid hormone free B5 medium containing $2\%$ sucrose. Embryo yields were significantly higher after 1- and 2-day pretreatment at $32^{\circ}C$. However the development of embryo ceased at the globular or heart stage. In contrast, embryo yields were lower after 3- to 6-day pretreatment at $32^{\circ}C$ and embryo developed at the cotyledonary stage. After adding the 2-hydroxynicotinic acid to anther pretreatment solution, embryo yields were slightly increased. However most embryos occurred were at the globular or heart stage. Co-pretreatment of microspores with anthers was deleterious for embryo induction and development. AS far as we know, this is the first report of success in obtaining high frequency of embryogenesis and plantlets formation from isolated microspores of pepper. Although the culture conditions have to be optimized further, this promising microspore culture system can be used for genetic transformation, selection for dominant and recessive traits as well as for the production of homozygous doubled haploid plants.