• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2471-2476
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• 2014

The aim of the present study is to explore the possibility of utilizing loess for the adsorption of total phosphorous (T-P) and total nitrogen (T-N) in water. Batch adsorption studies were performed to evaluate the influences of various factors like initial concentration, contact time and temperature on the adsorption of T-P and T-N. The adsorption data showed that loess is not effective for the adsorption of T-N. However, loess exhibited much higher adsorption capacity for T-P. At concentration of $1.0mgL^{-1}$, approximately 97% of T-P adsorption was achieved by loess. The equilibrium data were fitted well to the Langmuir isotherm model. The pseudo-second-order kinetic model appeared to be the better-fitting model because it has higher $R^2$ compared with the pseudo-first-order and intra-particle kinetic model. The theoretical adsorption equilibrium $q_{e,cal}$ from pseudo-second-order kinetic model was relatively similar to the experimental adsorption equilibrium $q_{e,exp}$. The thermodynamic parameters such as free energy ${\Delta}G$, the enthalpy ${\Delta}H$ and the entropy ${\Delta}S$ were also calculated.

• Journal of Embryo Transfer
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• v.10 no.2
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• pp.171-175
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• 1995

This study was performed to establish the condition and the methods for the techniques of insertion the isolated blastomere cells into cytoplasm, in order to research the develop-mental ability of bovine embryo blastomere cells in vitro produced. After 24h in vitro ovary maturation with the ovaries from a slaughter house, in vitro fertilization was performed to the vital sperms which their mobility were decided by percoll gradient method, with 2~8 cell stage embryos, the blastomeres were isolated in $Ca^2$+. $Mg^2$+-free PBS, and following that embedded into agar and alginate solution, respectively. The rates of in vitro develop-ment are as follows ; in agar embedded 11 among 120(9.2%) 1 /2~1 /3 blastomers cleaved and 6 among 93(6.5%) 1 /4~1 /8 blastomeres cleaved. In sodium alginate-embedded 14 among 84(16.7%) 1 /2~1 /3 blastomeres cleaved and 6 among 85(7.1%) 1 /4~1 /8 blastomeres cleaved. In case of Na-alginate, the rate of the cells were better than those of agar. The results suggest that the techniques for embeeding the isolated blastomeres into gel may help cloning of bovine early embryo without nuclear transplantation.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.3
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• pp.79-84
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• 2007

Because synaptic refinement of medial nucleus of trapezoid body (MNTB) - lateral superior olive (LSO) synapses is most active during the first postnatal week and the long term depression (LTD) has been suggested as one of its mechanisms, LTD of MNTB-LSO synapses was investigated in neonatal rat brain stem slices with the whole cell voltage clamp technique. In $Mg^{2+}$ free condition, tetanus (10 stimuli at 10 Hz for 2 min) in the current clamp mode induced a robust LTD of isolated D, L-APV-sensitive postsynaptic currents (PSCs) for more than 30 min ($n=6,\;2.4{\pm}0.4%$ of the control), while isolated CNQX-sensitive PSCs were not suppressed ($n=6,\;95.3{\pm}1.6%$). Tetanus also elicited similar LTD in the isolated GABAergic/glycinergic PSCs ($n=6,\;3.6{\pm}0.5%$) and mixed PSCs (GABAergic/glycinergic/glutamatergic) ($n=4,\;2.2{\pm}0.7%$). However, such a strong LTD was not observed in the mixed PSCs when 10 mM EGTA was added in the internal solution (n=10), indicating that postsynaptic $Ca^{2+}$ rise is needed for the strong LTD. This robust LTD might contribute to the active synaptic refinement occurring during the first postnatal week.

• Bulletin of the Korean Chemical Society
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• v.16 no.5
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• pp.401-406
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• 1995

The P. fragi lipase overexpressed in E. coli as a fusion protein of 57 kilodalton (kDa) has been purified through glutathione-agarose affinity chromatography by elution with free glutathione. The general properties of the purified GST-fusion protein were characterized by observing absorbance of released p-nitrophenoxide at 400 nm which was hydrolyzed from the substrate p-nitrophenyl palmitate. The optimum condition was observed at 25 $^{\circ}C$, pH 7.8 with 0.4 ${\mu}g$ of protein and 1.0 mM substrate in 0.6% (v/v) TritonX-100 solution. Also the lipase was activated by Ca+2, Mg+2, Ba+2 and Na+ but it was inhibited by Co+2 and Ni+2. pGEX-2T containing P. fragi lipase gene as expression vector was named pGL191 and used as a template for the site-directed mutagenesis by sequential PCR steps. A Ser-His-Asp catalytic triad similar to that present in serine proteases may be present in Pseudomonas lipase. Therefore, the PCR fragments replacing Asp217 to Arg and His260 to Arg were synthesized, and substituted for original fragment in pGL19. The ligated products were transformed into E. coli NM522, and pGEX-2T harboring mutant lipase genes were screened through digestion with XbaI and StuI sites created by mutagenic primers, respectively. No activity of mutant lipases was observed on the plate containing tributyrin. The purified mutant lipases were not activated on the substrate and affected at pH variation. These results demonstrate that Asp217 and His260 are involved in the catalytic site of Pseudomonas lipase.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.536-545
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• 2019

An experiment was conducted to evaluate the adsorptive removal of Pb(II) from an aqueous solution using a mixture of spent coffee grounds and chitosan on beads (CC-beads). Various parameters affecting the adsorption process of Pb(II) using CC-beads were investigated. Based on the experimental data, the adsorption kinetics and adsorption isotherms were analyzed for their adsorption rate, maximum adsorption capacity, adsorption energy and adsorption strength. Moreover, the entropy, enthalpy and free energy were also calculated by thermodynamic analysis. According to the FT-IR analysis, a CC-bead has a very suitable structure for easy heavy metal adsorption. The process of adsorbing Pb(II) using CC-beads was suitable for pseudo-second order kinetic and Langmuir model, with a maximum adsorption capacity of 163.51 (mg/g). The adsorption of Pb(II) using CC-beads was closer to chemical adsorption than physical adsorption. In addition, the adsorption of Pb(II) on CC-beads was exothermic and spontaneous in nature. CC-beads are economical because they are inexpensive and also the waste can be recycled, which is very significant in terms of the continuous circulation of resources. Thus, CC-beads can compete with other adsorbents.

• Journal of Yeungnam Medical Science
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• v.35 no.2
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• pp.213-218
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• 2018

Background: Body fats, especially both of abdominal fat pad mass and skeletal muscle fat content, are inversely related to insulin action. Therefore, methods for decreasing visceral fat mass and muscle triglyceride content may be helpful for the prevention of insulin resistance. Methods: Thalidomide, used for its anti-angiogenic and anti-inflammatory properties, was administered to rats for 4 weeks. A 10% solution of thalidomide in dimethyl sulfoxide was injected daily into the peritoneal cavity as much as 100 mg/kg of body weight. Results: The total visceral fat pad mass in the thalidomide-treated group was 11% lower than in the control group. The size of adipocytes of the epididymal fat pad mass in the thalidomide-treated group was smaller than in the control group. The intraperitoneal thalidomide treatment increased triglyceride concentrations by 16% in the red muscle, but not in the white muscle. Conclusion: The results suggested that intraperitoneal thalidomide treatment inhibited abdominal fat accumulation, and that the free fatty acids in the blood were preferentially accumulated in the red muscle rather than in the white muscle.

• Journal of Chest Surgery
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• v.30 no.9
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• pp.847-853
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• 1997

Although the effects of adenosine on the heart, including the clinical suppression of cardiac arrhythmias, have been recognized for more than half a century, it is only in the last decade that the therapeutic potential of adenosine has been recognized. The objective of this study was to determine if augmentation of myocardial adenosine levels during global ischemia improves functional recovery after reperfusion. We used to modified Langendonf system to evaluate myocardial protective effect. Isolated rat hearts were subjected to 90 minutes of deep hypothermic arrest(15$^{\circ}C$) with modified St. Thomas'Hospital cardioplegic solution used to provide myocardial protection. Myocardial adenosine levels were augmented during ischemia by providing exogenous adenosine in the cardioplegic solution. Two groups of hearts w re studied: (1) control group(n=10) cardioplegia alone; (2) adenosine group(n=10) adenosine(0.75mg/kg/min) added to the cardioplegic solution. Significantly better percent recovery(p<0.01) in hemodynamics(except heart rate) at 60 minutes after reperfusion was evident compared to baseline values in the adenosine group. (systolic no란ic pressure : 78.5$\pm$3.6% vs 66.6$\pm$5.9%, airtic overflow volume : 61.7$\pm$ 11.6% vs 37.2$\pm$ 15.4%, coronary flow volume 77.1$\pm$7.5% vs 57.2$\pm$ 11.1%, and cardiac output : 65.6$\pm$ 11.5% vs 44.2$\pm$ 12.4%). Heart rate was similar in two groups(94.4$\pm$4.8% vs 95.3 $\pm$ 6.8%). Adenosine groups resulted in significantly rapid recovery time of heart beat after reperEusion(p<0.01) (24.5$\pm$7.6 sec. vs 179.0$\pm$ 131.1sec.). In biochemical study, CPK levels(0.1 $\pm$0.3U/L vs 1.4$\pm$0.8U/L) and lactic acid levels(0.08$\pm$0.Immol/L vs 0.34$\pm$0.2 mmol/L) were significantly low in adenosine groups(p<0.01). We concluded that adenosine included cardioplegia have better recovery effects after r perfusion in myocardial ischemia compared to adenosine free cardioplegia.

• Applied Microscopy
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• v.13 no.1
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• pp.13-30
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• 1983

[ $1-{\beta}-D-Arabinofuranosylcytosine$ ](ara-C), which is a pyrimidine nucleoside analog is cytotonic to mammalian cells in culture and is active in vitro and in vivo against a variety of DNA viruses. The precise mechanism of action of ara-C has not been determined, although ara-C is thought to act as an antimetabolite, interfering with the synthesis of deoxyribonucleic acid(DNA). Cytosine arabinoside originally seemed to act principally by inhibiting the conversion of cytidine to deoxytidine, thus inhibiting DNA synthesis. But recent data suggest that effects upon DNA polymerase and effects via incorporation into DNA and RNA may well be of equal importance. The author have demonstrated the effect of cytosine arabinoside on the hepatocytes of albino mice treated with ara-C, observing changes in the cytoplasmic organelles of the hepatocytes. A total of 120 healthy male albino mice were divided into the control and ara-C treated groups. The animals of the ara-C group were given 10mg. per kg of body weight of mouse ara-C in physiological saline solution and the animals of control group were given physiological saline solution, intraperitoneally. After an administration of ara-C or physiological saline solution, the animal were killed at. interval of 6, 12, and 24 hours. The specimens, which were obtained from the left anterier lobe of the liver, were stained with uranyl acetate and lead citrate and observed with JEM 100B electron microscope. The results were obtained as follow: A pronounced dilatation, sacculation and fragmentation of the cisterane of rough endoplasmic reticulum with dissociation of membrane bound-ribosomes, disaggregation of free ribosomes in the cytoplasm, proliferation of the smooth endoplasmic reticulum associated with depletion of glycogen paracles, atrophies of Golgi complex, production of numerous lipid droplets, and formation of antophagic vacuoles, multivesicular bodies and residual bodies are recognized in the hepatocytes of ara-C treated mice. Consequently it is suggested that cytosine arabinoside would induce a changes of the cytoplasmic organelles of the hepatocytes in albino mice.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.5
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• pp.602-610
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• 2013

This study was aimed to evaluate the cavernosal relaxation effect of Crataegii fructus(CF) in the contracted rabbit penile corpus cavernosum by agonists.In order to study the effect of CF on the vasoconstriction of rabbit penile corpus cavernosum, isolated rabbit penile corpus cavernosum tissues were used for the experiment using organ baths containing Krebs solution.To investigate the cavernosal relaxation of CF, CF extract at $0.01{\sim}3.0mg/m{\ell}$ was added after penile corpus cavernosum were contracted by norepinephrine(NE) $1{\mu}M$. To analyze the mechanism of CF's vasorelaxation, CF extract infused into contracted penile tissues by NE after each treatment of indomethacin(IM), $N{\omega}$-nitro-L-arginine(L-NNA), methylene blue(MB), tetraethylammonium chloride(TEA).To study the effect of CF on influx of extracellular calcium chloride($Ca^{2+}$) in penile tissues, in $Ca^{2+}$-free krebs solution, $Ca^{2+}$ 1 mM infused into contracted penile tissues by NE after pretreatment of CF. Cytotoxic activity of CF on human umbilical vein endothelial cell(HUVEC) was measured by MTT assay, and nitric oxide(NO) prodution was measured by Griess reagent. CF relaxed cavernosal strip with endothelium contracted by NE, but in the strips without endothelium, CF-induced relaxation was significantly inhibited. The pretreatment of L-NNA, MB, TEA decreased significantly on the cavernosal relaxation than not-treatment of them. But the pretreatment of IM had no significant effect on the cavernosal relaxation. In $Ca^{2+}$-free krebs solution, when $Ca^{2+}$ infused into contracted penile tissues by NE, pretreatment of CF inhibit contraction induced by adding $Ca^{2+}$.NO production wasn't increased by treatment of CF on HUVEC. This findings showed that CF is effective for the relaxation of rabbit penile corpus cavernosum, and we suggest that CF relax rabbit corpus cavernosal smooth muscle through multiple action mechanisms that include increasing the release of nitric oxide from corporal sinusoidal endothelium, inhibition of $Ca^{2+}$ mobilization into cytosol from the extracellular fluid, and maybe a hyperpolarizing action.

• Journal of Embryo Transfer
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• v.12 no.2
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• pp.133-139
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• 1997

Large scale production of cloned embryos requires the technology of multiple generational nuclear transfer(NT) by using NT embryos itself as the subsequent donor nuclei. In this work we investigated comparatively the effects of enucleated oocytes treated with ionomycin and 6-DMAP on the electrofusion rate and in vitro developmental potential in the first and second NT embryos. The embryos of 16-cell stage were collected from the mated does by flushing oviducts with Dulbecco's phosphate buffered saline(D-PBS) containing 10% fetal calf serum(FCS) at 47 hours after hCG injection. The recipient cytoplasms were obtained by removing the nucleus and the first polar body from the oocytes collected at 15 hours after hCG injection. The enucleated oocytes were pre-activated by 5 min incubation in 5$\mu$M ionomycin and 2 hours incubation in 2 mM 6-DMAP at 19~20 hours post-hCG before microinjection. In the first and second generation NT, the unsynchronized 16-cell stage embryos were used as nuclear donor. The separated donor blastomeres were injected into the enucleated activated recipient oocytes by micromanipulation and were electrofused by electrical stimulation of single pulse for 60 $\mu$sec at 1.25kV/cm in $Ca^2$+, $Mg^2$+ - free 0.28 M mannitol solution. In the non-preactivation group, the electrofusion and electrical stimulation was given 3 pulses for 60 $\mu$sec at 1.25 kV/cm in 100$\mu$M $Ca^2$+, $Mg^2$+ 0.28 M mannitol solution. The fused oocytes were co-cultured with a monolayer of rabbit oviductal epithelial cells in TCM-199 solution containing 10% FCS for 120 hours at 39$^{\circ}C$ in a 5% $CO_2$ incubator. The results obtained were summarized as follows: 1. In the first generational NT embryos, the electrofusion rate of preactivated and non-activated oocytes(80.4 and 87.8%) was not significantly different, but in the second generational NT embryos, the electrofusion rate was significantly(P<0.05) higher in the non-activated oocytes(85.7%) than in the preactivated oocytes(70.1%). 2) In the first and second generational NT embryos, the developmental potential to biastocyst stage was significantly(P<0.05) higher in the preactivated oocytes(39.3 and35.7%) than in the non-preactivated oocytes(16.0 and 13.3%). No significant difference in the developmental potential was shown between the first and second generational NT embryos derived from the preactivated oocytes. In conclusion, it may be efficient to use the oocytes preactivated with ionomycin and 6-DMAP for the multiple production of cloned embryos by recycling nuclear transfer.