• Archives of Pharmacal Research
• /
• v.25 no.5
• /
• pp.647-651
• /
• 2002

An LC/MS/MS method for the simultaneous determination of a neuroprotective agent for ischemia-reperfusion damage, KR-31378 and its N-acetyl metabolite KR-31612 in human plasma was developed. KR-31378, KR-31612 and the internal standard. KR-31543 were extracted from human plasma by liquid-liquid extraction. A reverse-phase HPLC separation was performed on Luna phenylhexyl column with the mixture of acetonitrile-5 mM ammonium formate (55:45, v/v) as mobile phase. The detection of analytes was performed using an electrospray ionization tandem mass spectrometry in the multiple reaction monitoring mode. The lower limits of quantification for KR-31378 and KR-31612 were 2.0 ng/ml. The method showed a satisfactory sensitivity, precision, accuracy, recovery and selectivity.

• Journal of Plant Biology
• /
• v.36 no.3
• /
• pp.211-218
• /
• 1993

Plant regeneration was accomplished from protoplast culture of rice (Oryza sativa L. cv. Taebaeg). Embryogenic callus was induced from mature seed on MS medium containing 5 mM proline, 2.5 mg/L 2,4-D, 30 g/L sucrose in the dark at 28$^{\circ}C$ and used to establish embryogenic cell suspension culture. Suspension cells were subcultured every one week in N6 medium supplemented with 5 mM proline, 200 mg/L casein hydrolysate, 2.5 mg/L 2,4-D and amino acids of AA medium. Suspension cultures were composed of cells that were densely cytoplasmic, potentially embryogenic and were at least maintained for more than 6 months in liquid medium. Protoplasts were isolated from fast-growing suspension culture cells and cultured in a slightly modified KpR medium by mixed nurse culture. Isolated protoplasts began to divide within 5~7 days and thereafter, protoplast-derived calli were sequentially transferred to callus proliferating medium that soft agar MS medium contained 2 mg/L 2,4-D and produced distinct embryogenic cells. Microcolonies were then transferred to solid medium which consisted of MS medium containing 5 mg/L kinetin, 1 mg/L NAA, 1 mg/L ABA, 30 g/L sucrose and 10 g/L sorbitol under fluorescent light. Mulitple shoots of 4~5 per callus emerged and were transferred to hormone-free MS medium for root initiation. Thereafter, The plantlets were transferred to pots of soil to mature in the culture room.

• Molecules and Cells
• /
• v.23 no.3
• /
• pp.340-348
• /
• 2007

Although considerable effort has been devoted in the mass spectrometric analysis of phosphorylated peptides, successful identification of multi-phosphorylated peptides in enzymatically digested protein samples still remains challenging. The ionization behavior of multi-phosphorylated peptides appears to be somewhat different from that of mono- or di-phosphorylated peptides. In this study, we demonstrate increased sensitivity of detection of multi-phosphorylated peptides of beta casein without using phosphopeptide enrichment techniques. Proteinase K digestion alone increased the detection limit of beta casein multi-phosphorylated peptides in the LC-MS analysis almost 500 fold, compared to conventional trypsin digestion (~50 pmol). In order to understand this effect, various factors affecting the ionization of phosphopeptides were investigated. Unlike ionizations of phosphopeptides with minor modifications, those of multi-phosphorylated peptides appeared to be subject to effects such as selectively suppressed ionization by more ionizable peptides and decreased ionization efficiency by multi-phosphorylation. The enhanced detection limit of multi-phosphorylated peptides resulting from proteinase K digestion was validated using a complex protein sample, namely a lysate of HEK 293 cells. Compared to trypsin digestion, the numbers of phosphopeptides identified and modification sites per peptide were noticeably increased by proteinase K digestion. Non-specific proteases such as proteinase K and elastase have been used in the past to increase detection of phosphorylation sites but the effectiveness of proteinase K digestion for multi-phosphorylated peptides has not been reported.

• Journal of Animal Science and Technology
• /
• v.47 no.6
• /
• pp.1067-1074
• /
• 2005

In order to optimize tissue culture conditions of Kentucky bluegrass(Poa pratensis L.), effects of culture medium supplements, media and cultivars on embryogenic callus induction and regeneration of plants were investigated. MS medium containing 3mg/L 2,4-D and 0.1mg/L BA was optimal for embryogenic callus induction from mature seeds. The highest plant regeneration frequency(57.7%) was observed when the embryogenic calli were cultured on N6 medium supplemented with 1mg/L 2,4-D and 3mg/L BA. Among several basic media, MS and N6 medium were optimal for callus induction and plant regeneration, respectively. Genotype was an important factor in plant regenerability. ‘Newport’ showed to have higher regeneration frequency of 53.4%. Regenerated plants were grown normally when shoots transplanted to the soil. A short tissue culture period and high-frequency regeneration system would be beneficial for molecular breeding of Kentucky bluegrass through genetic transformation.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.6
• /
• pp.729-735
• /
• 1996

This study was carried out to investigate the effect of Germaniwn(Ge) treatment in the culture media on the Ge absorption by the callus induced from brown rice cv. Dongjinbyeo. MS medium was more effective on the growth ratio of callus and the content of Ge and some inorganic elements except K in callus than N$_{6}$ medium. The more Ge treatment in the N$_{6}$ or MS medium, the more Ge absorption by the callus, but the growth ratio of callus and the content of Ca, Mg, and K in callus were decreased. The content of Fe, Mn, Zn, and Cu was increased under treatment up to 100～200mg /$\ell$ Ge, but tended to be decreased under treatment more than that of Ge concentration. Under treatment less than 150mg /$\ell$ Ge, GeO$_2$(inorganic Ge) was more effective on the Ge absorption by callus than Ge-132(organic Ge), but Ge-132 was more effective on the Ge ab-sorption by callus and the activity of callus in case of treatment more than 150mg /$\ell$ Ge. The lower pH of culture medium, the higher Ge content in the callus. When callus was cultured on medium supplemented with Ge and 0.1～1.0mM of citric acid or myo-inositol, content of Ge and some inorganic elements in callus, as well as growth and dry weight of callus, were tend to increase in comparison to control, but myo-inositol was more effective on them than citric acid.cid.

• Korean Journal of Food Science and Technology
• /
• v.26 no.6
• /
• pp.750-758
• /
• 1994

Flavour components of seven Korean folk sojues, five Chinese kaoliangchiews and Japanese shochu were determined by GC and GC-MS after solid phase extraction with polydivinyl benzene. Less volatile ethyl succinate and ethyl pelargonate were present in Korean folk sojues while volatile ethyl acetate and ethyl butyrate in Chinese kaoliangchiews. In the case of alcohols, the amount of isopentyl alcohol was relatively higher than that of isobutyl alcohol or n-propyl alcohol in Korean folk sojues. On the contrary, less volatile n-propyl alcohol was present more than isopentyl alcohol in Chinese kaoliangchiews. Multivariate statistical analyses involving principal components analysis (PCA) and discriminant analysis (DA) were applied to the GC data. The results of PCA clearly demonstrate that the first principal scores of Korean folk sojues were similar but the second principal scores were different from each other. Classification of Korean sojues and Chinese kaoliangchiews into two groups could be conducted by DA. These results suggested that the common charateristics and identities as a distilled liquors was found in Korean folk sojues.

• Journal of Plant Biotechnology
• /
• v.31 no.1
• /
• pp.43-48
• /
• 2004

As an initial step for future genetic manipulations to improve forage characteristics of Italian ryegrass (Lolium multiflorum Lam.), an efficient tissue culture system was established and the factors affecting plant regeneration were evaluated. MS medium containing 5mg/L 2,4-D was optimal for embryogenic callus induction from mature seed and had a strong effect on successive plant regeneration. The plant regeneration frequency was observed at above 70％ when embryogenic calli induced were transferred to N6 medium supplemented with 1mg/L 2,4-D and 5mg/L BA. Among several basic media tested, MS and N6 medium were optimal for callus induction and plant regeneration, respectively. Genotype was an important factor in plant regenerability. 'Jeanne' showed the highest regeneration frequency of 73％. A short tissue culture period and high-frequency regeneration system established in this study will be useful for molecular breeding of Italian ryegrass through genetic transformation.

• Reproductive and Developmental Biology
• /
• v.36 no.3
• /
• pp.183-188
• /
• 2012

The bovine fatty acid binding protein 4 and 5 (FABP4 and 5) is a major positional and physiological candidate gene for the bovine marbling and carcass weight. The aim of this study was to evaluate the association between economic traits of Korean cattle (Hanwoo) and genetic variation in fatty acid binding protein 4 and 5 (FABP4 and 5) genes within carcass/meat quality traits and the before/after of fatting in breed Hanwoo. Here, we characterized the nucleotide polymorphism of FABP4 and 5 in 86 cattle. We were detected the variability of three types (GG, AG, and AA) by PCR, and economic traits were analyzed by the mixed regression model implemented in the ASReml program. As the result of statistical and supersonic analysis, FABP4 gene was highly showed significant effect (p<0.006) on marbling score (MS), in contrast FABP5 gene was lowed (p<0.084) on MS before fatting. But, FABP4 gene was highly showed significant effect (p<0.0054) on MS, in contrast FABP5 gene lowest (p<0.0899) on MS in the after of fatting. Compare to supersonic result before fatting in FABP4 gene, it was detected type GG: (p<7.18), AG: (p<8.50), and AA: (p<10.50) (n=50), showed type GG: (p<4.88), AG: (p<2.33), and AA: (p<0.00) after weed out (n=20). Futhermore, it was detected type GG: (p<9.30), AG: (p<7.95), and AA: (p<7.40) (n=50) before fatting in the FABP5 gene. It was shown type GG: (p<2.67), AG: (p<3.50), and AA: (p<5.00) after weed out (n=50). Our results indicate that FABP4 and 5 gene transcription is regulated by the environment of feeding and management, and suggest that feeding and management could be potential key in determining FABP4 and 5 genes transcription for carcass/meat quality traits in breed Hanwoo.

• Polymer(Korea)
• /
• v.37 no.3
• /
• pp.276-287
• /
• 2013

Two kinds of N,O-hydroxypropyl chitosans (HPCTOs) with degree of substitution (DS) and molar substitution (MS) ranging from 2.15 to 2.39 and 2.9 to 4.1, respectively, and five kinds of aliphatic acid esters of HPCTOs (HPCTOAms, m=0,2,4,7,9, the number of methylene units in aliphatic substituent) based on the HPCTOs were synthesized, and the thermotropic liquid crystalline properties of the derivatives were investigated. All the derivatives formed enantiotropic cholesteric phases whose optical pitches (${\lambda}_m$'s) increased with increasing temperature. However, the glass and clearing temperatures, the magnitude of ${\lambda}_m$ of the mesophase at the same temperature, and the temperature dependence of ${\lambda}_m$ of the investigated derivatives highly depended on MS and m. The thermotropic mesophase properties of HPCTOAms were significantly different from those reported for the aliphatic acid esters of hydroxypropyl celluloses. The results indicate that the secondary amino group in the C-2 position plays an important role in the thermal stabilization and temperature dependence of ${\lambda}_m$ of the cholesteric mesophase.

• Progress in Medical Physics
• /
• v.17 no.2
• /
• pp.96-104
• /
• 2006

Experiments from several groups Including ours have demonstrated that $Ca^{2+}$ can enhance the inactivation of N-type calcium channels. However, it is not clear if this effect can be ascribed to a 'classic' $Ca^{2+}$-dependent inactivation (CDI) mechanism. One method that has been used to demonstrate CDI of L-type calcium channels is to alter the intracellular and extracellular concentration of $Ca^{2+}$. In this paper we replaced the external divalent cation to monovalent ion ($MA^+$) to test CDI. In the previous paper, we could separate fast (${\tau}{\sim}150ms$) and slow (${\tau}{\sim}2,500ms$) components of inactivation in both $Ba^{2+}$ and $Ca^{2+}$ using 5-sec voltage step. Lowering the external divalent cation concentration to zero abolished fast inactivation with relatively little effect on slow inactivation. Slow inactivation ${\tau}$ correspond very well with provided the $MA^+$ data is shifted 10 mV hyperpolarized and slow inactivation ${\tau}$ decreases with depolarization voltage in both $MA^+\;and\;Ba^{2+}$, which consistent with a classical voltage dependent inactivation (VDI) mechanism. These results combined with those of our previous paper lead us to hypothesize that external divalent cations are required to produce fast N-channel inactivation and this divalent cation-dependent inactivation is a different mechanism from classic CDI or VDI.