• KSBB Journal
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• v.11 no.4
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• pp.411-419
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• 1996

In this research, an extractive production system for alkaloids, where production and some degree of separation occur simultaneously, was developed in a way that the fast removal of alkaloid produced from the suspension cultures was done by capturing alkaloid with cyclodextrins. The alkaloid production was substantially enhanced up to 40 fold when the solid cultures of E. califonica cells treated with ${\beta}$-cyclodextrin compared to the control. The enhancement of alkaloid production was also observed in the suspension cultures. Interestingly, the production pattern seemed to change when the cultures were treated with ${\beta}$-cyclodextrin so that the major part of the alkaloids in the treated cultures was present in the medium, while the non-treated cultures produced the alkaloids intracellularly. ${\beta}$-cyclodextrin was the most effective one in terms of the alkaloid production among the cyclodextrilns(${\alpha}$-cylodextrin, ${\beta}$-cyclodextrin and ${\gamma}$-cyclodextrin) tested in the suspension cultures. ${\beta}$-cyclodextrin showed no adverse effect on the cell growth. The most effective concentration of ${\beta}$-cyclodextrin was observed around 1.5% (w/v) in the suspension cultures. The formation of the inclusion complex of the alkaloids with ${\beta}$-cyclodextrin in the suspension cultures was confirmed by detecting the shift of UV absorbance from 274 nm to 282 nm with a UV spectrophotometer.

• Korean Journal of Materials Research
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• v.13 no.6
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• pp.347-351
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• 2003

II-Ⅵ ZnO compound semiconductor thin films were grown on $\alpha$-Al$_2$O$_3$(0001) single crystal substrate by radical beam assisted molecular beam epitaxy and the optical properties were investigated. Zn(6N) was evaporated using Knudsen cell and O radical was assisted at the partial pressure of 1$\times$10$^{4}$ Torr and radical beam source of 250-450 W RF power. In $\theta$-2$\theta$ x-ray diffraction analysis, ZnO thin film with 500 nm thickness showed only ZnO(0002)and ZnO(0004) peaks is believed to be well grown along c-axis orientation. Photoluminescence (PL) measurement using He-Cd ($\lambda$=325 nm) laser is obtained in the temperature range of 9 K-300 K. At 9 K and 300 K, only near band edge (NBE) is observed and the FWHM's of PL peak of the ZnO deposited at 450 RF power are 45 meV and 145 meV respectively. From no observation of any weak deep level peak even at room temperature PL, the ZnO grains are regarded to contain very low defect density and impurity to cause the deep-level defects. The peak position of free exciton showed slightly red-shift as temperature was increased, and from this result the binding energy of free exciton can be experimentally determined as much as $58\pm$0.5 meV, which is very closed to that of ZnO bulk. By van der Pauw 4-point probe measurement, the grown ZnO is proved to be n-type with the electron concentration($n_{e}$ ) $1.69$\times$10^{18}$$cm^3$, mobility($\mu$) $-12.3\textrm{cm}^2$/Vㆍs, and resistivity($\rho$) 0.30 $\Omega$$\cdot$cm.

• Journal of Acupuncture Research
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• v.18 no.2
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• pp.51-66
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• 2001

The purpose of this morphological studies was to investigate the central neural pathway projecting to the acupoints $B_{62}$ and $K_6$ using the neuroanatomical method following injection of transsynaptic neurotropic virus, pseudorabies virus(PRV-Ba and PRV-Ga) into the $B_{62}$ and $K_6$. After survival times of 96 hours following injection into the twenty rats with PRV-Ba(Bartha strain) and PRV-Ga(Bartha strain, ${\beta}$-galacidodase insertion). They were perfused, and their spinal cord and brain were frozen sectioned($30{\mu}m$). These sections were stained by X-gal histochemical and PRV immunohistochemical staining method, and observed with light microscope. The results were as follows : 1. In spinal cord, overlaped PRV-Ba and PRV-Ga labeled neurons projecting to the $B_{62}$ and $K_6$ were founded in thoracic, lumbar and sacral spinal segments. In thoracic spinal segments, Densely labeled areas were founded in lamina IV, V, VII(intermediolateral nucleus) and X areas. In lumbar segemnts, labeled areas were founded in lamina II, IV, V and X areas. In sacral spinal segments, labeled areas were founded in lamina IV, V and VI areas. 2. In brain, overlaped PRV-Ba and PRV-Ga labeled neurons projecting to the $B_{62}$ and $K_6$ were founded in the $A_1$ noradrenalin cells/$C_1$ adrenalin cells/caudoventrolateral reticular nucleus, rostroventrolateral reticular nuclens, nucleus tractus solitarius, area postrema, raphe obscurus nucleus, raphe paltidus nucleus, raphe magnus nucleus, lateral paragigantoceltular nucleus, lateral rcticular nucleus, gigantocellular nucleus, locus coeruleus, subcoeruleus nucleus, motor trigeminal nucleus, Kolliker-Fuse nucleus, $A_5$ cell group, central gray matter, oculomotor nerve, paraventricular hypothalamic nucleus, median eminence, amygdaloid nucleus, frontal cortex, forelimb area, hindlimb area, 1, 2 areas of parietal cortex and granular and agranular cortex. This results were suggest that overlaped PRV-Ba and PRV-Ga labeled areas projecting to the $B_{62}$ and $K_6$ may be related to the emotional relay pathway in the central autonomic center.

• YAKHAK HOEJI
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• v.51 no.2
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• pp.150-156
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• 2007

Some flavonoids have spasmolytic activities in various smooth muscles, but structure-activity relationships on their spasmolytic activity and its mechanism are unclear. In this study, effects of flavones (flavone and apigenin) and flavonols (quercetin and rutin) on the rat ileal smooth muscle contraction were studied in vitro and in vitro. In the electric stimulation-induced contraction, all of four flavonoids inhibited concentration-dependently the rat ileal smooth muscle contraction induced by electric stimulation (10 mV, 0.1 cps, 0.1 msec duration), IC$_{50}$ of quercetin, apigenin, flavone and rutin were 0.98${\times}$10$^{-5}$, 1.20${\times}$10$^{-5}$, 1.55${\times}$10$^{-5}$ and 1.85${\times}$10$^{-5}$ M, respectively. Flavonoids at a concentration of 2${\times}$10$^{-5}$ M also significantly inhibited the anaphylactic contraction and decreased concentration-dependently the mast cell degranulation by anaphylactic reaction, IC$_{50}$ of quercetin, apigenin, flavone and rutin were 4.0${\times}$10$^{-5}$, 7.5${\times}$10$^{-5}$, 8.0${\times}$10$^{-5}$ and 9.5${\times}$10$^{-5}$ M, respectively. These results indicated that flavones and flavonols inhibited the rat ileal smooth muscle contraction induced by electric stimulation because of their antagonism against acetylcholine and have spasmolytic activities on anaphylactic contraction which may be due to their mast cell-stabilizing activities. Furthermore, double bond of C$_{2,3}$ in benzene ring of flavonoids may be important in the their antispasmodic activities on the rat ileal smooth muscle contraction induced by electric stimulation and anaphylactic reaction.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1991.06a
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• pp.37-44
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• 1991

영산강 하구언 방조제의 건설로 인한 항만 및 이의 인접해역 해면의 변화는 예상한 바 있으며 실제 여러개소에서 월 2회정도의 주기로 목포 구항부근 상업지역에서 해면상승에 따라 주기적으로 침수되는 현상이 나타나고 있다 목포항의 영산강 하구언 방조제 조성으로 인한 조류성분중 최고기록을 가진 수로에서는 6kts 정도로 감소된 것으로 보고되고 있으나 주위자연환경 변화에 따른 수면 상승 및 해수면의 주기적인 변화 등에 대한 상세한 언급 및 깊이 있는 분석은 회피되어왔다. 수자원의 효율적관리를 위해 하구언 방조제는 이미 건설되었고 앞으로 대규모의 항만개발과 대불산업단지조성을 위해 추가 3개의 만입해안해역에 댐으로 해역을 막아 매립공사를 추진하고 있다 그러나 이 지역에 대한 분석은 타당성의 여부만을 강조한 상업적 용역이 이루어지고 있고 장래 개발에 대해 학술적이고 실질적인 문제점 추출과 해결방아네 대해서는 무시하거나 경시한 바가 많다 더구나 태풍 저기압 등과 같은 자연재해를 고려한 분석은 시도되지 못하고 있다 따라서 개발전후의 현상에 대한 상세한 자료 및 현장 조사와 극한 상태를 고려하여 개발에 따른 수위상승 부진동, 조류 수질등 이해역의 변화요소를 수집하고 분석하며 과학적 접근방법에 기초를 둔 수치모델의 실험을 포함하여 현장관측 및 측정자료를 검증하는 것이 필수적이라고 사료되어 종합분석의 한단계로 여기서는 하구언 및 하구간척(Land Reclamatic of Estuary barren)으로 해역축소에 따른 해면변화의 실제현상을 조사하여 정리하고 이를 수치모델을 통해 시뮬레이션하여 보았다 이는 종합개발의 좋은 기초자료로 이용됨은 물론이로 이지역의 개발에 기여할 것으로본다.적절하게 가정된 지반의 응력-변형률 관계와 간극수압특성에 의하여 고려되었다. 그 결과 응력 및 변위가 심하게 발생하는 지역은 황색 점토층이었으며 이로부터 황색 점토층에서 부터 파괴면이 생성되어 다른 지역으로 전파되었음을 유추할 수 있었다.form trap with 2.88[eV] deep of injected space charge from the chathode in the crystaline regions. The origin of ${\alpha}$$_2$ peak was regarded as the detrapping process of ions trapped with 0.9[eV] deep originated from impurity-ion remained in the specimen during production process of the material, in the crystalline regions. The origin of ${\beta}$ peak was concluded to be due to the depolarization process of "C=0"dipole with the activation energy of 0.75[eV] in the amorphous regions. The origin of ${\gamma}$ peak was responsible to the process combined with the depolarization of "CH$_3$", chain segment, with the activation energy of ca

• Proceedings of the Korean Society of Medical Physics Conference
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• 2003.09a
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• pp.82-82
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• 2003

Introduction: With the development of dose calculation algorithms for electron beams, 3D RTP systerns are available for electron beam dose distribution commercially. However, no studies evaluated the accuracy of dose calculation with ADAC Pinnacle system for electron beams. So, the accuracy of the ADAC system is investigated by comparing electron dose distributions from ADAC system against the BEAMnrc/DOSXYZnrc. Methods: A total of 33 breast cancer patients treated with 6, 9, and 12MeV electrons in our institution was selected for this study. The first part of this study is to compare the dose distributions of measurement, TPS and the BEAMnrc/DOSXYZnrc code in flat water phantom at gantry zero position and for a 10 ${\times}$ 10 $\textrm{cm}^2$ field. The second part is to evaluate the monitor unit obtained from measurement and TPS. Adding actual breast patient's irregular blocks to the first part, monitor units to deliver 100 cGy to the dose maximum (dmax) were calculated from measurement and 3D RTP system. In addition, the dose distributions using blocks were compared between TPS and the BEAMnrc/DOSXYZnrc code. Finally, the effects of tissue inhomogeneities were studied by comparing dose distributions from Pinnacle and Monte Carlo method on CT data sets. Results: The dose distributions calculated using water phantom by the TPS and the BEAMnrc/ DOSXYZnrc code agreed well with measured data within 2% of the maximum dose. The maximum differences of monitor unit between measured and Pinnacle TPS in flat water phantom at gantry zero position were 4% for 6 MeV and 2% for 9 and 12 MeV electrons. In real-patient cases, comparison of depth doses and lateral dose profiles calculated by the Pinnacle TPS, with BEAMnrc/DOSXYZnrc code has generally shown good agreement with relative difference less than +/-3%. Discussion: For comparisons of real-patient cases, the maximum differences between the TPS and BEAMnrc/DOSXYZnrc on CT data were 10%. These discrepancies were due in part to the inaccurate dose calculation of the TPS, so that it needs to be improved properly. Conclusions: On the basis of the results presented in this study, we can conclude that the ADAC Pinnacle system for electron beams is capable of giving results absolutely comparable to those of a Monte Carlo calculation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.1
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• pp.8-13
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• 2010

The angiotensin converting enzyme (ACE) inhibition effect of soybean protein isolate hydrolysate was studied using protease. Soybean protein isolate was hydrolysed by seven enzymes (Alcalase 2.4 L, Flavourzyme 500 MG, GC 106, Multifect Neutral, Neutrase 0.8 L, Papain 30,000 and Protamex), enzyme concentrations (0, 0.5, 1.0 and 1.5%), at various hydrolysis times (0, 1, 2, 3, 4, 5 and 6 hr) and suspension concentrations (1, 5, 7, 10 and 15%). Absorbance at 280 nm, brix and ACE inhibitory activity of soybean protein isolate hydrolysates were investigated. Absorbance at 280 nm and brix of Alcalase 2.4 L treatment were higher than other enzyme treatments. The optimum condition of hydrolysis was Alcalase 2.4 L, 1% enzyme concentration, 5% suspension concentration for 4 hr. $IC_{50}$ value of ACE inhibitory activity of soybean protein isolate hydrolysate was $79.94 {\mu}g/mL$. These results suggest that soybean isolate protein hydrolysate from Alcalase 2.4 L may be of benefit for developing antihypertensive therapeutics.

• Progress in Superconductivity and Cryogenics
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• v.15 no.2
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• pp.34-38
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• 2013

AC Losses for face to face stacks of four identical coated conductors (CCs) were numerically calculated using the H-formulation combined with the E-J power law and the Kim model. The motive sample was the face to face stack of four 2 mm-wide CC tapes with 2 ${\mu}m$ thick superconducting layer of which the critical current density, $J_c$, was $2.16{\times}10^6A/cm^2$ on IBAD-MgO template, which was suggested for the mitigation of ac loss as a round shaped wire by Korea Electrotechnology Research Institute. For the calculation the cross section of the stack was simply modeled as vertically aligned 4 rectangles of superconducting (SC) layers with $E=E_o(J(x,y,t)/J_c(B))^n$ in x-y plane where $E_o$ was $10^{-6}$ V/cm, $J_c$(B) was the field dependence of current density and n was 21. The field dependence of the critical current of the sample measured in four-probe method was employed for $J_c$(B) in the equation. The model was implemented in the finite element method program by commercial software. The ac loss properties for the stacks were compared with those of single 4 cm-wide SC layers with the same critical current density or the same critical current. The constraint for the simulation was imposed in two different ways that the total current of the stack obtained by integrating J(x,y,t) over the cross sections was the same as that of the applied transport current: one is that one fourth of the external current was enforced to flow through each SC. In this case, the ac loss values for the stacks were lower than those of single wide SC layer. This mitigation of the loss is attributed to the reduction of the normal component of the magnetic field near the SC layers due to the strong expulsion of the magnetic field by the enforced transport current. On the contrary, for the other case of no such enforcement, the ac loss values were greater than those of single 4cm-wide SC layer and. In this case, the phase difference of the current flowing through the inner and the outer SC layers of the stack was observed as the transport current was increased, which was a cause of the abrupt increase of ac loss for higher transport current.

• Korean Journal of Veterinary Research
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• v.37 no.1
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• pp.119-128
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• 1997

The relaxation of gastric fundus smooth muscles is the primary physiological event which induces the receptive relaxation of monogastric animals. L-arginine/Nitric oxide(L-arg/NO) system is known to mediate the inhibitory non-adrenergic non-cholinergic(NANC) neurotransmission in various tissues including gastrointestinal smooth muscles. The longitudinal smooth muscles of porcine gastric fundus showed fast relaxation during electrical field stimulation(EFS) and rebound contraction after EFS in NANC condition. So, the purpose of present study was elucidation of the neurotrasmitters related to the NANC relaxation and explanation of the relation between NANC relaxation and L-arg/NO system. The longitdinal smooth muscles of porcine gastric fundus were hung in the organ bath and under the presence of guanethidine($5{\times}10^{-5}M$), precontraction was induced by carbachol($1{\times}10^{-6}M$). The muscle responses to EFS and drugs were isomerically recorded. The rusults were summarized as follows. 1. The longtudinal muscles of porcine gastric fundus showed frequency-dependent relaxation and rebound contraction to electrical field stimulaton(1ms, 8V, 1~16Hz, 20sec, EFS). These responses were blocked by tetrodotoxin($1{\times}10^{-6}M$). 2. The relaxation and rebound contraction of the longitudinal muscles of porcine gastric fundus to EFS were inhibited by L-NAME($2{\times}10^{-5}M$). The inhibitory effect of L-NAME was antagonized by L-arginine($1{\times}10^{-3}M$), but not by D-arginine($1{\times}10^{-3}M$). 3. Exogenous NO($NaNO_2$, $1{\times}10^{-5}{\sim}1{\times}10^{-4}M$, pH=2.0) caused concentration-dependent relaxation as EFS did. 4. Methylene Blue($2{\times}10^{-5}M$), a soluble guanylate cyclase inhibitor, inhibited the relaxation and rebound contraction of the longitudinal muscles of porcine gastric fundus induced by EFS, but N-ethlmaleimide, a adenylate cyclase inhibitor, did not. 5. 8-Br-cGMP($1{\times}10^{-6}{\sim}3{\times}10^{-6}M$), permeable cGMP analogue, induced dose-dependent relaxation. but 8-Br-cAMP($1{\times}10^{-6}{\sim}3{\times}10^{-6}M$), permeable cAMP analogue, did not. Both did not evoked rebound contraction. 6. ${\alpha}$-chymotrypsin did not affect the relaxation of the longitudinal muscles of porcine gastric fundus. 7. Reactive blue 2($1{\times}10^{-4}M$, 40min) siginificantly inhibited the rebound contraction induced by EFS and inhibited contraction caused by exogenous ATP($1{\times}10^{-4}{\sim}1{\times}10^{-3}M$). These results suggests that NANC relaxation of the longitudinal muscles of porcine gastric fundus mainly mediated by NO and the rebound contraction is related to NO and other neurotransmitters.

• Biomolecules & Therapeutics
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• v.6 no.2
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• pp.219-224
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• 1998

The bioequivalence of two clarithromvcin products was evaluated with 16 normal male volunteers (age 23-28 yr, body weight 57.5-75.517g) following single oral dose. Test product was ReYon Clarithromycin tablets (ReYon Pharm. Corp., Korea) and reference product was Klarici $d_{R}$ tablets (Abbott Korea). Both products contain 250 mg of clarithromucin. One tablet of the test or the reference product was administered to the volunteers, respectively, by randomized two period cross-over study (2$\times$2 Latin square method). The determination of clarithromycin was accomplished using a modified agar well diffusion bioassay. As a result of the assay validation, the quantification of clarithromycin in human serum by this technique was possible down to 0.03$\mu$g/ml using 100$\mu$l of serum. The coefficient of variation (C.V.) was less than 10%. Average drug concentrations at each sampling time and pharmacokinetic parameters calculated were not significantly different between two products P>0.05); the area under the curve to last sampling time (24 hr) (AU $Co_{24hr}$ (8.10$\pm$ 1.26 vs 8.22$\pm$ 1.627g . hr/ml), AUC from time zero to infinite (AU $Co_{\infty}$) (8.61 $\pm$ 1.28 vs 8.84$\pm$ 1.71 $\mu$g . hr/ml), maximum plasma concentration ( $C_{msx}$) (0.87$\pm$0.22 vs 0.88$\pm$0.19 $\mu$g/ml) and time to maximum plasma concentration ( $T_{max}$) (2.69 $\pm$0.48 vs 2.56$\pm$ 0.51 hr). The differences of mean AU $Co_{24h}$, $C_{msx}$ and $T_{msx}$ between the two products (1.44, 1.39, and 4.65%, respectively) were less than 20%. The power (1-$\beta$) and treatment difference ($\Delta$) for AU $Co_{24hr}$, and $C_{max}$ were more than 0.8 and less than 0.2, respectivly. Although the power for $T_{max}$ was under 0.8, $T_{max}$. of the two products was not significantly different each other (p>0.05). These results suggest that the bioavailability of ReYon Clarithromycin tablets is not significantly different from that of Klarici $d_{R}$ tablets. Therefore, two products are bioequivalent based on the current results. results.sults.sults.s.s.s.s.s.s.s.