• 한국해양학회지
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• v.3 no.1
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• pp.1-7
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• 1968

Two major processes that affect the vertical distribution of apparent pH in the Subarctic region of the Northeastern Pacific Ocean are (1) apparent oxygen utilization by marine organisms and (2) carbonate dissolution. Simplified mathematical approximations show that, in the pH ravge of 7.2 to 8.3, the utilization of 0.1 mM of oxygen (2.24 ml/liter) lowers the pH by 0.20 units and 0.1 mM of carbonate dissolution increases the pH by 0.25 units. Since Oxygen utilization exceeds 0.3 mM while the carbonate dissolution, with respect to the surface, is about 0.05mM, the effect of oxygen utilization is much greater than the dissolution effect of carbonate on the pH of seawater.

• Molecules and Cells
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• v.20 no.3
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• pp.423-428
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• 2005

Immediately after fertilization, a chromatin remodeling process in the oocyte cytoplasm extracts protamine molecules from the sperm-derived DNA and loads histones onto it. We examined how the histone H3-lysine 9 methylation system is established on the remodeled sperm chromatin in mice. We found that the paternal pronucleus was not stained for dimethylated H3-K9 (H3-$m_2K9$) during pronucleus development, while the maternal genome stained intensively. Such H3-$m_2K9$ asymmetry between the parental pronuclei was independent of $HP1{\beta}$ localization and, much like DNA methylation, was preserved to the two-cell stage when the nucleus appeared to be compartmentalized for H3-$m_2K9$. A conspicuous increase in H3-$m_2K9$ level was observed at the four-cell stage, and then the level was maintained without a visible change up to the blastocyst stage. The behavior of H3-$m_2K9$ was very similar, but not identical, to that of 5-methylcytosine during preimplantation development, suggesting that there is some connection between methylation of histone and of DNA in early mouse development.

• Nuclear Engineering and Technology
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• v.34 no.2
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• pp.146-153
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• 2002

To radiolabel bioactive molecules, we synthesized $^{99m}$Tc-tricarbonyl precursor, [$^{99m}$Tc(CO)$_3$($H_2O$)$_3$]$^{+}$ with a low oxidation state ( I ). The [$^{99m}$Tc(CO)$_3$($H_2O$)$_3$]$^{+}$ was prepared by low pressure carbonylation (1 atm of CO) of [$^{99m}$Tc $O_4$)]$^{[-10]}$ in the presence of NaB $H_4$ resulting in higher than 98% of labeling yield and stability up to 8 hrs. We evaluated the characteristics of $^{99m}$Tc- tricarbonyl labeled bioactive molecules by carrying out in vitro and in vitro study. Prepared [$^{99m}$Tc(CO)$_3$($H_2O$)$_3$]$^{+}$ was then reacted with some ligands of significance in modem diagnostic nuclear medicine and some amino acids. Labeling yields were checked by HPLC and found to be usually high, excluding $^{99m}$Tc-tricarbonyl-MDP, -EDTMP and -mIBG. And the biodistribution properties of $^{99m}$Tc-tricarbonyl complexes applied in rabbit showed different appearance comparing with that of the $^{99m}$Tc-labeling by conventional means. From these results, we conclude that [$^{99m}$Tc(CO)$_3$($H_2O$)$_3$]$^{+}$ is a potential precursor for development of radiopharmaceuticals, especially for labeling of biomolecules.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.49-57
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• 1994

The binding properties of oxomemazine to muscarinic receptors using the ability of oxomemazine to inhibit $[^3H]QNB$ binding in membrane fractions of rat cerebrum and guinea pig ventricle and ileum were investigated. $[^3H]QNB$ bound to a single class of muscarinic receptors with a dissociation constant of approximately 60 pM in three tissue preparations. Pirenzepine and oxomemazine inhibited $[^3H]QNB$ binding in cerebrum with a Hill coefficient lower than unity, and the inhibition data were best described by a two-site model. The relative densities of the high $(M_1)\;and\;low\;(M_2)$ affinity sites for pirenzepine were 60 and 40%, with corresponding Ki values of 16 and 431 nM, and those $(O_H\;and\;O_L)$ for oxomemazine 40 and 60%, with corresponding Ki values of 80 and 1350 nM. However, the inhibition data of both drugs vs $[^3H]QNB$ in ventricle and ileum appeared to obey the law of mass-action (Hill coefficient close to 1). The apparent Ki values of pirenzepine were 850 and 250 nM, and those of oxomemazine 1460 and 570 nM in ventricle and ileum, respectively. Thus, oxomemazine like pirenzepine has high affinity for cerebrum, moderate affinity for ileum and low affinity for ventricle. These results suggest that oxomemazine could recognize the muscarinic receptor subtypes with a high affinity for the $M_1$ sites.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.132-140
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• 1998

Laboratory-scale experiments were conducted using a three-stage rotating biological contactor unit followed by lime precipitation and sedimentation with effluent recycle to the first stage. The purpose of this study was to evaluate the effects of hydraulic loadings of 0.031-0.076 $m^3/m^2/d and recycle ratio of 1 to 3 on the simultaneous removal of organics and nutrients from domestic wastewater. Lime was added to maintain pH of 10.4-11.0 in the coagulation-flocculation reactor. Results showed that the highest nitrogen removal rate of 70.5% occurred at the lower hydraulic loading of 0.031 $m^3/m^2/d at a recirculation rate of 300%, and similarly, highest nitrification occurred at the same hydraulic loading and recycle ratio. Concentration of ammonia nitrogen in the effluent was less than 1 mg/l at the same operating conditions for higher nitrogen removal. Whereas, high BOD and COD removal was observed at hydraulic loading rate of 0.054 $m^3/m^2/d, and high removal of organic matter was evident from the consistent low COD and BOD value. Results obtained from the operating condition of higher loading rate, 300% of recycle rate showed the highest removals. Increasing in recycle rate and hydraulic loading rate increased the volatile solids fraction of the sludges generated to the extent of 47% at 0.076 $m^3/m^2/d hydraulic loading and 300% recirculation rate. Since pH in the flocculator was maintained at the pH of 10.4-11.0, above 90% removal of phosphorus was obtained. Average concentration of suspended solids was always maintained over 40 mg/l in the effluent. Therefore an RBC unit operating at a hydraulic loading near 0.031 $m^3/m^2/d with a recycle rate of 300% is a viable and feasible alternate conditions to produce an effluent with relative low organic matter and phosphorus, provided that there is a neutralization unit to control the pH and SS of the effluent.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.67-72
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• 2001

$H^+-ATPase$ located on plasma and vacuolar membranes play major roles in various cellular physiological processes. In order to investigate the physiological roles of $H^+-ATPase$, microsomes were prepared from tomato roots and the effects of various anions were measured on the activities of $H^+-ATPase$. $H^+-ATPase$ was inhibited by various anions. Citrate and phosphate were chosen to investigate detailed inhibitory mechanisms on $H^+-ATPase$ since they showed different levels of inhibition. Inhibitory effect of citrate was observed at the concentrations above 3 mM. When 20 mM citrate was added, the ATPase activity was decreased by 50-60%. However, the inhibitory effect of citrate was decreased by increasing the concentration of$Mg^{2+}$ The citrate-induced inhibited activity was recovered by the addition of $Mg^{2+}$ Addition of 7 mM $Mg^{2+}$ completely removed the inhibitory effect of citrate and the activity recovered to the level of the control experiment. These results imply that citrate chelates $Mg^{2+}$ and thus inhibits $H^+-ATPase$. Meanwhile, the inhibitory effect of phosphate was observed at the concentration above 3 mM and the activity was decreased by 50% in the presence of 30 mM phosphate. Further addition of $Mg^{2+}$ showed no recovery on the activity. These results imply that the inhibitory effect of phosphate is not dependent upon the concentration of $Mg^{2+}$.

• Journal of Aquaculture
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• v.21 no.4
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• pp.259-264
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• 2008

Cytogenetic characteristics of three Hemibarbus species (H. labeo, H. longirostris and H. mylodon) were analyzed based on erythrocyte measurement, flow cytometric estimation of cellular DNA content, and karyological analysis. Average nuclear volumes for H. labeo, H. longirostris and H. mylodon were 22.5, 21.7 and $26.0\;{\mu}m^3$, respectively. The estimated genome sizes of those three species were not significantly different from one another, being recorded as 2.51, 2.33 and 2.35 pg/cell for H. labeo, H. longirostris and H. mylodon, respectively. Modal chromosome numbers of the three species were the same as 2n = 50. However, their karyotypes and fundamental numbers (FN) were different among species; 16M+16SM+18T/A (FN = 82) for H. labeo, 18M+16SM+16T/A (FN = 84) for H. longirostris and 18M+24SM+8T/A (FN = 92) for H. mylodon.

• Korean Journal of Plant Resources
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• v.25 no.4
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• pp.482-489
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• 2012

Effect of Trichosanthes kirilowii extract on the inflammatory responsse was investigated in the lipopolysaccharide (LPS)-treated broiler chickens. Plasma ceruloplasmin and ${\alpha}$-acidic protein concentrations of all the experiment groups were increased at 3, 9 and 24h after LPS treatment. Plasma ceruloplasmin and ${\alpha}$-acidic protein concentrations of Trichosanthes kirilowii extract groups were lower than those of control group. Plasma nitrogen oxide concentration of all the experiment groups was rapidly increased at 3h after LPS treatment. However, plasma nitrogen oxide concentration was decreased at 3 and 9h after LPS treatment with increasing amount of Trichosanthes kirilowii extract added. Liver IL-2 mRNA concentration of all the experiment groups was rapidly increased at 2h after LPS treatment, and then gradually decreased to the level similar to that before LPS treatment at 9h after LPS treatment. Liver IL-2 mRNA concentration of Trichosanthes kirilowii extract groups were lower than that of control group. Spleen IL-2 mRNA concentration was the highest at 4h after LPS treatment in all the experiment groups. Spleen IL-2 mRNA concentration of 0.2 and 0.3% Trichosanthes kirilowii extract groups were higher than that of 0.1% Trichosanthes kirilowii extract group and control group at 3 and 4h after LPS treatment. Liver and spleen IFN-${\gamma}$ mRNA concentrations were increased at 2 and 3h after LPS treatment, decreased at 4h after LPS treatment, and then reached to the level similar to that before LPS treatment at 9h after LPS treatment. Liver and spleen IFN-${\gamma}$ mRNA concentrations of Trichosanthes kirilowii extract group were lower than those of control group at 2h and 3h after LPS treatment. Liver and spleen iNOS mRNA concentrations were the highest at 3h after LPS treatment, and then decreased to the level similar to that before LPS treatment at 9h after LPS treatment. Liver and spleen iNOS mRNA concentrations of Trichosanthes kirilowii extract groups were lower than those of control group at 2, 3 and 4h after LPS treatment.

• BMB Reports
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• v.31 no.6
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• pp.548-553
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• 1998

A minor anionic isoperoxidase named $A_{3n}$, was isolated from Korean radish (Raphanus sativus L.) root. Purification of the enzyme was accomplished by CMcellulose chromatography, DEAE-Sephacel chromatography, and Sephadex G-75 gel filtration. The enzyme was a glycoprotein with molecular weight of approximately 31,000 as determined by SDS-PAGE and 33,000 by Sepadex G-150 gel filtration, which is by far the smallest among the reported isoperoxidases. The pI value was 3.5. The optimum pH of the enzyme was 6.5 for guaiacol and $H_2O_2$, and the $K_m$ values for guaiacol and $H_2O_2$ were 13.3 mM and 1.5 mM, respectively. Kinetic studies with various substrates revealed that only A3n, unlike other isoperoxidases from radish, did not use scopoletin as a substrate and had very low $K_m$ value of 0.25 mM for ferolic acid among naturally occurring phenolic substrates.

• The Korean Journal of Applied Statistics
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• v.10 no.1
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• pp.61-68
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• 1997

In this paper, we show that the proper equi-replicate binary designs with h($h\geq2$)-concurrence most balanced designs are (M, S)-optimal. It is very difficult to construct with more than 3-concurrence designs, so we choose 3-concurrence most balanced designs out of the known PBIBD(3).