• 한국토양환경학회지
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• 제4권3호
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• pp.25-33
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• 1999

본 연구는 석유계탄화수소로 오염된 토양의 토양증기추출시 발생되는 가솔린 배가스의 바이오필터법 처리가능성을 검토하기 위하여 실시하였다. 바이오필터 충전물질로는 퇴비를 사용하였다. 약 50g/㎥(충전물질)/hr의 유입부하에서 TPH제거능력은 약 40g/$\textrm{m}^3$((충전물질)/hr를 나타내어 80%정도의 제거 효율을 나타내었다. 자일렌은 BTEX중에서 제거효율이 가장 우수하였으며, 벤젠은 제거효율이 가장 낮아 최대제거능력은 약 1.5g/$\textrm{m}^3$(충전물질)hr이었다. 0.79g/$\textrm{m}^3$((충전물질)/hr미만의 부하량에서의 TMB(trimethylbenzene)와 나프탈렌의 제거효율은 95%이상이었다. 바이오필터법의 처리시 생물학적 반응에 의한 TPH와 BTEX의 제거효율은 약 80%이었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1690-1691
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• 2011

본 논문에서는 H1N1 인플루엔자 A 바이러스(influenza A H1N1 virus) 검출을 위한 산화아연 나노구조(zinc oxide nano structure) 기반의 전기화학적 면역센서를 제작하고 그 특성을 분석하였다. H1N1 인플루엔자 A 바이러스는 빠른 전파 속도 때문에 정확하고 빠른 검출이 필요하다. 먼저, 2 $mm^2$의 표면적을 갖는 패턴된 금 전극 위에 열수방식(hydrothermal method)으로 성장시킨 산화아연 나노구조가 선택적으로 형성되도록 리프트-오프(lift-off) 방법을 사용하였다. 0.01 M phosphate buffered saline(pH 7.4)에서 2 ${\mu}g$/mL 농도의 1차 항체를 정전기력에 의해 산화아연 나노구조에 고정화한 후, 10 pg/mL ~ 5ng/mL 농도의 H1N1 항원을 적용하여 포획 항체에 결합시키고 HRP(horseradish peroxidase) 효소가 결합된 검출 항체를 항원에 결합시키는 샌드위치 ELISA법을 이용하였다. HRP와 반응하는 TMB(3,3', 5,5'-tetramethylbenzidine)와 과산화수소가 포함된 acetate buffered 용액(pH 5)을 전해질로 사용하고 순환전압전류 측정법(cyclic voltammetry)으로 센서의 특성을 분석하였다. 측정된 순환전압전류그래프(cyclic voltammogram)에서 H1N1 항원 농도 10 pg/mL ~ 5 ng/mL의 응답 전류는 276.47 ${\pm}$ 21.72 nA (평균 ${\pm}$ 표준편차, n=4) ~ 478.89 ${\pm}$ 6.21 nA로 측정되었고, logarithmic하게 증가하는 응답 전류 특성을 보였다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2010년도 추계학술발표논문집 1부
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• pp.495-499
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• 2010

The biocatalytic capture of $CO_2$, and its precipitationas $CaCO_3$, over bovine carbonic anhydrase (BCA) immobilized on a pore-expanded SBA-15 support was investigated. SBA-15 was synthesized using TMB as a pore expander, and the resulting porous silica was characterized by XRD, BET, IR, and FE-SEM analysis. BCA was immobilized on SBA-15 through various approaches, including covalent attachment (BCA-CA), adsorption (BCA-ADS), and cross-linked enzyme aggregation (BCA-CLEA). The immobilization of BCA on SBA-15 was confirmed by the presence of zinc metal in the EDXS analysis. The effects of pH, temperature, storage stability, and reusability on the biocatalytic performance of BCA were characterized by examining para-nitrophenyl acetate (p-NPA) hydrolysis. The $K_{cat}/K_m$ values for p-NPA hydrolysis were 740.05, 660.62, and $680.11M^{-1}s^{-1}$, respectively, where as $K_{cat}/K_m$ for free BCA was $873.76M^{-1}s^{-1}$. The amount of $CaCO_3$ precipitate was measured quantitatively using anion-selective electrode and was found to be 12.41, 11.82, or 11.28 mg $CaCO_3$/mg for BCA-CLEA, BCA-ADS, or BCA-CA, respectively. The present results indicate that the immobilized BCA-CLEA, BCA-ADS, and BCA-CA are green materials, and are tunable, reusable, and promising biocatalysts for $CO_2$ sequestration.

• 대한한방내과학회지
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• 제26권2호
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• pp.379-389
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• 2005

Objectives: It is well known that aging and aging-related diseases are linked to the increased level of oxidative stress caused by reactive oxygen species(ROS) and reactive nitrogen species(RNS). Nonprotein-SH decreases during aging, while substances such as ROS, nitric oxide(NO), peroxynitrite($ONOO^-$), myeloperoxidase(MPO), and dityrosine show a significant increase. This study investigated the effect of Ichungwhan on the aging process by examining its effect on the generation of the above-mentioned substances. Methods: Four comparison groups of SD rats were used. They were 6 month-old rats, 24 month-old rats, and 24 month-old rats fed with food containing 0.1% and 0.3% of Ichungwhan extract. The amount of NO, $ONOO^-$, and ROS in the rats' kidneys were examined using a fluorescence microplate reader. The reagents used for this purpose include: dihydrorhodamine 123 (DHR 123), 2',7' -dichlorodihydrofluorescein, diacetate(DCFDA), and 4,5-diaminofluorescein(DAF-2). A spectrophotometer was used to investigate the reactivity of nonprotein-SH and myeioperoxidase(MPO), using reagents such as trichloroacetic acid(TCA) and tetramethylbenzidine(TMB). The amounts of MPO protein and dityrosine were measued by western blot. Results: The observed effects of Ichungwhan on rats were as follows: increase of nonprotein-SH; effective decrease of RNS level by suppression of the generation system of $ONOO^-$ and NO; decrease of ROS level; decrease of the MPO reactivity and the subsequent reduction of amount of MPO protein; retardation of dityrosine formation. It can be hypothesized, therefore, that Ichungwhan affects both the earlier and later phases of the molecular inflammatory process, and retards the aging process. Conclusions: Empirical evidence in this study supports a role for Ichungwhan in generation mechanisms of aging process-linked substances ROS, NO, $ONOO^-$, nonprotein-SH, MPO and dityrosine. Affects contrary to the aging process observed in rats beg further empiricism to investigate potential application of Ichungwhan as a medication for age-related diseases in humans.

• 한국지진공학회논문집
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• 제11권2호
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• pp.47-56
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• 2007

본 연구에서는 지진하중을 받는 탄성 및 비탄성 구조물에 대하여 수동 및 준능동 TMD의 지진응답제어성능을 평가하였다. 먼저 기존의 연구에서 제안된 식을 사용하여 최적 설계된 수동형 TMD와 본 연구에서 제시된 준능동 TMB가 설치된 탄성 구조물의 변위스펙트럼을 구하였으며, 준능동 TMD가 TMD보다 작은 스트로크를 가지고도 최대변위응답제어에 있어 우수함을 확인하였다. 또한 구조물의 주기와 TMD의 주기가 일치하지 않은 경우의 성능저하에 대한 TMD의 강인성을 평가하였다. 최종적으로 Bouc-Wen 모델을 사용하여 모사된 비탄성이력 특성을 가지는 구조물에 대한 수치해석을 수행하였으며, 이를 통해 탄성구조물에 대하여 최적화된 수동형 TMD의 성능은 구조물 응답의 비탄성이력 부분이 증가함에 따라 크게 저하되는 반면 준능동 TMD는 수동형 TMD보다 약 15-40% 정도의 더 많은 응답감소효과를 가짐을 확인하였다.

• Archives of Pharmacal Research
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• 제14권1호
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• pp.55-67
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• 1991

The influence of caffeine on secretion of catecholamines (CA) was examined in the isolated perfused rat adrenal gland. Caffeine (0.3 mM) perfused into an adrenal vein of the gland produced a marked increase in secretion of CA. This secretory effect of CA evoked by perfusion of caffeine for one minute was considerably prolonged, lasting for more than 90 minutes. The tachyphylaxis to releasing effect of CA induced by caffeine was observed by repeated perfusion of this drug. The caffeine-evoked CA secretion was markedly inhibited by pretreatment with ouabain, trifluoperazine, TMB-8 and perfusion with calcium-free Krebs solution containing 5 mM EGTA, but was not affected by perfusion of calcium-free Krebs solution without other addition. CA secretion evoked by caffeine was not reduced significantly by pretreatment with chlorisondamine but after the first collection of perfusate for 3 min was clearly inhibited. Interestingly, the caffeine-evoked CA secretion was considerably potentiated by pretreatment with atropine or pirenzepine, but after the first collection for 3 min it was markedly decreased. These experimental results suggest that caffeine causes a marked increase in secretion of CA from the isolated perfused rat adrenal gland by an extracellular calcium-independent exocytotic mechanism. The secretory effect of caffeine may be mainly due to mobilization of calcium from an intracellular calcium pool in the rat chromaffin cells and partly due to stimulation of both muscarinic and nicotinic receptors.

• Archives of Pharmacal Research
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• 제27권3호
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• pp.305-313
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• 2004

The effect of diazoxide, a $K^{+}$channel opener, on apoptotic cell death was investigated in HepG2 human hepatoblastoma cells. Diazoxide induced apoptosis in a dose-dependent manner and this was evaluated by flow cytometric assays of annexin-V binding and hypodiploid nuclei stained with propidium iodide. Diazoxide did not alter intracellular $K^{+}$concentration, and various inhibitors of $K^{+}$channels had no influence on the diazoxide-induced apoptosis; this implies that $K^{+}$channels activated by diazoxide may be absent in the HepG2 cells. However, diazoxide induced a rapid and sustained increase in intracellular $Ca^{2+}$ concentration, and this was completely inhibited by the extracellular $Ca^{2+}$ chelation with EGTA, but not by blockers of intracellular $Ca^{2+}$ release (dantrolene and TMB-8). This result indicated that the diazoxide-induced increase of intracellular $Ca^{2+}$ might be due to the activation of a Ca2+ influx pathway. Diazoxide-induced $Ca^{2+}$ influx was not significantly inhibited by either voltage-operative $Ca^{2+}$ channel blockers (nifedipinen or verapamil), or by inhibitors of $Na^{+}$, $Ca^{2+}$-exchanger (bepridil and benzamil), but it was inhibited by flufenamic acid (FA), a $Ca^{2+}$-permeable nonselective cation channel blocker. A quantitative analysis of apoptosis by flow cytometry revealed that a treatment with either FA or BAPTA, an intracellular $Ca^{2+}$ chelator, significantly inhibited the diazoxide-induced apoptosis. Taken together, these results suggest that the observed diazoxide-induced apoptosis in the HepG2 cells may result from a $Ca^{2+}$ influx through the activation of $Ca^{2+}$-permeable non-selective cation channels. These results are very significant, and they lead us to further suggest that diazoxide may be valuable for the therapeutic intervention of human hepatomas.

• The Journal of Advanced Prosthodontics
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• 제6권4호
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• pp.259-265
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• 2014

PURPOSE. The purpose of this study was to develop a dental image processing system using a three-dimensional (3D) camera and stereovision technology. The reliability of the system for measuring axial wall convergence angles was evaluated. MATERIALS AND METHODS. The new system predicted 3D coordinate points from 2D images and calculated distances and angles between points. Two examiners measured axial wall convergence angles for seven artificial abutments using a traditional tracing-based method (TBM) and the stereovision-based method (SVBM). Five wax abutment models of simplified abutment forms were made and axial wall convergence angles of wax models were measured by both methods. The data were statistically analyzed at the level of significance, 0.05. RESULTS. Intraclass correlation coefficients showed excellent intra-examiner and inter-examiner reliabilities for both methods. Bland-Altman plots and paired t-tests showed significant differences between measurements and true values using TBM; differences were not significant with SVBM. CONCLUSION. This study found that the SVBM reflected true angle values more accurately than a TMB and illustrated an example of 3D computer science applied to clinical dentistry.

• Preventive Nutrition and Food Science
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• 제11권2호
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• pp.140-145
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• 2006

Seventy eight bacterial strains were isolated from several jeotgals using MRS and M 17 agar media. The probiotic properties such as tolerance of extreme growth condition, production of antimicrobial compound, production of hydrogen peroxide, and enzymatic activity of bile salt hydrolase were investigated. DHK 4, 10, 21 and 74 strains showed_a strong tolerance property against extreme conditions such as low pH and 0.5% oxgall-supplemented medium. DHK 10 and 47 strains produced hydrogen peroxide on TMB agar plate. DHK 8 and 10 strains produced antimicrobial compounds onto MRS agar against E. facalis. DHK 4, 6, 21, 29, 33, 63 and 87 strains had high activities of bile salt hydrolase. Especially, DHK 10 displayed a strong probiotic candidate; the abilities to produce the antimicrobial compound, hydrogen peroxide, and bile salt hydrolase. All these strains are assumed to be useful probiotic candidates. Among 78, twenty seven strains which have probiotic properties were tentatively identified by 16S rRNA sequencing. Among them, 7 Lactobacillus spp., 6 Leuconosotoc spp., 2 Weisella spp., 1 Pediococcus sp., 1 Staphylococcus sp., 1 Enterococcus sp. and 2 Streptococcus spp. were tentatively identified.

• The Korean Journal of Physiology and Pharmacology
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• 제4권2호
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• pp.113-120
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• 2000

To investigate the mechanism of smooth muscle contraction induced by emptying of intracellular $Ca^{2+}$ stores, we measured isometric contraction and $^{45}Ca^{2+}$ influx. $CaCl_2$ increased $Ca^{2+}$ store emptying- induced contraction in dose-dependent manner, but phospholipase C activity was not affected by the $Ca^{2+}$ store emptying-induced contraction. The contraction was inhibited by voltage-dependent $Ca^{2+}$ channel antagonists dose dependently, but not by TMB-8 (intracellular $Ca^{2+}$ release blocker). Both PKC inhibitors (H-7 and staurosporine) and tyrosine kinase inhibitors (genistein and methyl 2,5-dihydroxycinnamic acid) significantly inhibited the contraction, but calmodulin antagonists (W-7 and trifluoperazine) had no inhibitory effect on the contraction. The combined inhibitory effects of protein kinase inhibitors, H-7 and genistein, together with verapamil were greater than that of each one alone. In $Ca^{2+}$ store-emptied condition, $^{45}Ca^{2+}$ influx was significantly inhibited by verapamil, H-7 or genistein but not by trifluoperazine. However combined inhibitory effects of protein kinase inhibitors, H-7 and genistein, together with verapamil were not observed. Therefore, this kinase pathway may modulate the sensitivity of contractile protein. These results suggest that contraction induced by emptying of intracellular $Ca^{2+}$ stores was mediated by influx of extracellular $Ca^{2+}$ through voltage-dependent $Ca^{2+}$ channel, also protein kinase C and/or tyrosine kinase pathway modulates the $Ca^{2+}$ sensitivity of contractile protein.