• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.128-128
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• 1998

Matrix metalloproteinases (MMPs) are a family of zinc-dependent proteases that degrade extracellular matrix and basement membrane. These enzymes are play important roles in tumor cell invasion and metastasis, as well as angiogenesis and other connective tissue diseases. In our screening program for inhibitors of MMP-2 from fungal metabolites, we have isolated novel non-peptidic inhibitors of MMPs, designated gelastatin A and B from the culture broth of Westerdykella multispora F50733. The structures of gelastatin A and B were determined to be 3-(5E-hexa-2E,4E-dienylidene-2-oxo-5,6-dihydro-2H-pyran-3yl)-propanoic acid and 3-(5Z-hexa-2E,4E-dienylidene-2-oxo-5,6-dihydro-2H-pyran-3yl)-propanoic acid, respectively. Gelastatin A and B exist as a mixture of two stereoisomers in a ratio of 2: 1. The 2: 1 mixture of gelastatin A and B inhibited activated MMP-2 and MMP-9 with an IC$\sub$50/ value of 0.63, 5.29 ${\mu}$M, respectively. They inhibited the invasion of B16F10 melanoma cells through basement membrane Matrigel with dose dependent.

• Advances in biomechanics and applications
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• v.1 no.1
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• pp.41-55
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• 2014

Acellular intra-myocardial biomaterial injections have been shown to be therapeutically beneficial in inhibiting ventricular remodelling of myocardial infarction (MI). Based on a biventricular canine cardiac geometry, various finite element models were developed that comprised an ischemic (II) or scarred infarct (SDI) in left ventricular (LV) antero-apical region, without and with intra-myocardial biomaterial injectate in layered (L) and bulk (B) distribution. Changes in myocardial properties and LV geometry were implemented corresponding to infarct stage (tissue softening vs. stiffening, infarct thinning, and cavity dilation) and injectate (infarct thickening). The layered and bulk injectate increased ejection fraction of the infarcted LV by 77% (II+L) and 25% (II+B) at the ischemic stage and by 61% (SDI+L) and 63% (SDI+B) at the remodelling stage. The injectates decreased the mean end-systolic myofibre stress in the infarct by 99% (II+L), 97% (II+B), 70% (SDI+L) and 36% (SDI+B). The bulk injectate was slightly more effective in improving LV function at the remodelling stage whereas the layered injectate was superior in functional improvement at ischemic stage and in reduction of wall stress at ischemic and remodelling stage. These findings may stimulate and guide further research towards tailoring acellular biomaterial injectate therapies for MI.

• The Transactions of the Korean Institute of Power Electronics
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• v.13 no.4
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• pp.303-310
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• 2008

Recently, IEC 61850 supports the standardized communication technique in both station bus and process bus, and presents substation automation model. In order to implement the IEC 61850 based communication in a substation using the MU (merging unit) which is one of the important data acquisition equipments in substation automation, the time synchronization is demanded for cooperative operation between the devices. This paper proposes the precision time synchronization technique using IRIG-B protocol to develop the MU under IEC 61850 communication protocol. The proposed technique is implemented and its performance is verified experimentally.

• Journal of Life Science
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• v.25 no.2
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• pp.130-135
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• 2015

When the alginate lyase gene (aly) from Pseudoalteromonas elyakovii IAM 14594 was expressed in E. coli, most of the gene product expressed was produced as aggregated insoluble particles known as inclusion bodies. In order to produce with an elevated level of a soluble and active form of alginate lyase in E. coli, the hyperthermophilic chaperonins (ApCpnA and ApCpnB) from archaeon Aeropyrum pernix K1 were employed as the coexpression partners. At $25^{\circ}C$ culture temperature, the level of alginate lyase activity was increased from 10.1 unit/g-soluble protein in aly single expression to 83.1 unit/g-soluble protein by coexpressing with ApCpnA and to 100.3 unit/g-soluble protein by coexpressing with ApCpnB. This results indicate that the coexpression of aly with ApCpnA and ApCpnB revealed a marked enhancement, about 8~10 fold, in the production of alginate lyase as a soluble and active form. Based on the results of various examinations on the expression variables, the optimal conditions for the maximal production of alginate lyase were determined as 1.0 mM IPTG for the inducer concentration, $25^{\circ}C$ for the culture temperature after IPTG induction, and ApCpnB for the coexpression partner. The coexpression set in the present report may be useful in the industrial production of functionally or medically important recombinant proteins in E. coli.

• Journal of the Korean Geosynthetics Society
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• v.18 no.2
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• pp.37-44
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• 2019

The compressive strength of the soil stabilizer in the deep mixing method (DMM) depends on kinds of soil, particle size distribution, and water content. Because of this, Laboratory test has to perform to estimate the unit weight of binder to confirm the satisfaction of the design strength. In this study, uniaxial compression strength was measured by mixing the soil stabilizers developed in the previous study with clay in Busan, Yeosu, and Incheon area. And the strength enhancement effect was evaluated comparing with blast furnace slag cement (BFSC). Also, the relationship between the unit content of binder and uniaxial compressive strength was investigated in order to easily calculate the unit weight of binder required to ensure the stability of the ground at the field. As the results of the analysis, the relationship between the unit content of binder and the uniaxial compressive strength are ${\gamma}_B=(108.93+0.0284q_u){\pm}35$ when W/B is 70%, and ${\gamma}_B=(122.93+0.0270q_u){\pm}40$ when W/B is 80%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.760-763
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• 2001

Five commercial salt-fermented shrimps contained 29.8~48.3% of salt 3.5%~7.3% of total nitrogen and 0.3~0.7g/100g of amino-nitrogen respectively. The average peptide length(APL) of five commercial salt-fermented shrimps ranged from 10.1 to 15.0. Sample B and E showed longer APL than the others with the values of 15.0 and 14.4 respectively. Protease activity showed the large differences in five samples from 17 unit to 232 unit ; sample C showed the highest protease activity with 232 unit while sample D and E were relatively lower with 17 unit and 18 unit respectively. The chitinase activities which can hydrolyze chitin the one of components on outer layer of shrimp ranged from 14.4 unit to 171 unit. Sample E had the highest chitinase activity as 171 unit but sample B showed the lowest activity with 14.4 unit. Chitooligosaccharides of five commercial salted-fermented shrimps were consisted of monoglucosamine diglucosamine and triglucosamine.

• The Korean Journal of Quaternary Research
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• v.13 no.1
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• pp.79-89
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• 1999

Three deep borings to obtain vertical continuous samples including weathered basement soils (KP-1, KP-2 and KP-3) were carried out in the reclaimed Kimpo tidal flat with purposes to establish late Quaternary stratigraphy. On the basis of detailed observations and descriptions on color, sedimentary structure and textural composition of cored sediments, four lithostratigraphic units are classified. From the stratigraphic top to bottom, they are Holocene tidal sand and muddy deposit (Unit I), early Holocene freshwater marsh muddy deposit (Unit II), late Pleistocene tidal sand and muddy deposit (Unit III) and late Pleistocene basal fluvial gravel deposit (Unit IV). In particular, Unit III is divided into two parts: the upper part-weathered and cryoturbated part during the Last Glacial Maximum (Unit III-a) and the lower part-unweathered tidal sand and muddy deposit (Unit III-b).

• Analytical Science and Technology
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• v.34 no.2
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• pp.37-45
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• 2021

A rapid and simple LC-MS/MS analytical method in determining Jaspine B has been developed and validated in rat plasma. The standard curve value was 25 - 5000 ng/mL and the linearity, inter-day and intra-day accuracy and precision were within 15.0 % of relative standard deviation (RSD). The mean recoveries of Jaspine B ranged from 87.5 % to 91.2 % with less than 3.70 % RSD and the matrix effects ranged from 91.1 % to 108.2 % with less than 2.6 % RSD. The validated LC-MS/MS analytical method of Jaspine B was successfully applied to investigate the dose-escalated pharmacokinetic study of Jaspine B in rats following an intravenous injection of Jaspine B at a dose range of 1 - 10 mg/kg. The initial plasma concentrations and area under plasma concentration curves showed a good correlation with intravenous Jaspine B dose, indicating the dose independent pharmacokinetics of Jaspine B in rats. In conclusion, this analytical method for Jaspine B can be easily applied in the bioanalysis and pharmacokinetic studies of Jaspine B, including its administration at multiple therapeutic doses, or for making pharmacokinetic comparisons for the oral formulations of Jaspine B in small experimental animals as well as in vivo pharmacokinetic-pharmacodynamic correlation studies.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.491-495
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• 1999

We compared the satellite observed temperature with the radiosonde observed temperature in the Korean Peninsula. The radiosonde observed data were obtained from four upper air observation stations in the Korean Peninsula from 1981 to 1998, and that was compared with the satellite observed data of the channel-2 and channel-4 of microwave sounding unit(MSU) on board NOAA series of polar-orbiting satellites. The radiosonde data were reconstructed into monthly radiosonde T$_{b}$ using MSU weighting function. The monthly climatology shows radiosonde T$_{b2}$ is higher than MSU T$_{b2}$ in summer. The correlation between MSU T$_{b2}$ and radiosonde T$_{b2}$ is 0.72-0.76 and 0.73-0.81 between MSU T$_{b4}$ and radiosonde T$_{b4}$.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.679-682
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• 2002

The alkaloids, piperlongumine, piperine, pipernonaline, and piperoctadecalidine, isolated from Piper longum L., were found to inhibit the biosynthesis of aflatoxin $B_1$ (AF$B_1$) in Aspergillus flavus WRRC 3-90-42-12. Piperlongumine was the most active among the compounds tested, with a 96% inhibition of AF$B_1$biosynthesis at 0.2% (w/v) supplement in a potato dextrose agar (PDA) medium. The three other piperidine alkaloids, pipeline, pipernonaline, and piperoctadecalidine, also inhibited the biosynthesis of AF$B_1$. Of these three alkaloids, piperoctadecalidine exhibited a potent inhibitory activity with a 100% inhibition of AF$B_1$ production at 0.7% (w/v) supplement in a PDA medium. Therefore, piperlongumine and piperoctadecalidine could be used as antiaflatoxigenic agents in agricultural industries. To determine the antiaflatoxigenic mode of action of piperlongumine, further studies are needed.