• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.21-28
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• 2000

A new fourty six 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)-N-phenylpro- pionamide derivatives were synthesized and the herbicidal activities against rice plant and barnyard grass with pre-emergence in down land were measured. The structure activity relationships (SAR) between the activities and physicochemical parameters of the substituted(X) N-phenyl group in substrates were analyzed and discussed by Free- Wilson and Hansch method from the basis on the former study (Sung. et. al., 1999). The conditions of selective herbicide activity both the barnyard grass and rice plant are shown that the optimal hydrophobicity, $({\pi})_{opt.}=1.34$ and electron donating with field effect (F<0) of meta and ortho, para-substituted mono or disubstituent on the N-phenyl ring were found to contribute significantly. The herbicidal activities against barnyard grass are roughly the same as the results in up land whereas damage to rice plant in down land more increase than that of up land. Degradation products in water are 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)propionic acid ((A)) (obs. pKa=4.35 & obs. logP=4.77) and 6-chloro-2-benzoxazolone (B) (obs. pKa=8.40 & obs. logP=2.90). These results were supposing that the hydrolysis product of substrates, (A) is comparatively absorbed in rice plant but not in barnyard grass. And it is assumed from the SAR equations that the 2,6-dimethyl-4-methoxymethyl group substituent ($pI_{50}=5.41$, 3g/ha) is selected as the most highest herbicidal activity against barnyard grass in green house.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.256-261
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• 2009

Molinate (S-ethyl hexahydro-1H-azepine-1-carbothioate), a selective, preemergence thiocarbamate herbicide used for grass weed control in rice fields, is being most widely used in Korea. This study was conducted to assess the comparative toxicity of molinate on two aquatic insects, Chironomus riparius and Cloeon dipterum in four larval stages. First-instar larvae of C. riparius appeared to be the most sensitive to acute exposure of molinate with a 48-h $EC_{50}$ of 7.8 mg/L, followed by third instar (48-h $EC_{50}\;=\;22.9\;mg/L$), second instar (48-h $EC_{50}\;=\;25.0\;mg/L$) and fourth instar (48-h $EC_{50}$ > 50 mg/L) larvae. Also, the sensitivity of the larvae of C. dipterum was presented as the same manner of the larvae of C. riparius. The youngest group of larvae of C. riparius appeared to be the most sensitive to molinate, with 96-h $EC_{50}$ values ranged from 14.3 to 24.1 mg/L. The authors assume that the young instar lavae of aquatic insects, Chironomus riparius and Cloeon dipterum are more sensitive to molinate. Also, the authors propose that Mayfly, Cloeon dipterum is well suited as a bioassay organism because it is one of the most vulnerable aquatic insects inhabiting agricultural ecosystem in Korea.

• The Journal of Korean Society for Radiation Therapy
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• v.27 no.2
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• pp.107-113
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• 2015

Purpose : The measurement of skin dose is very important that treatment of breast cancer. On account of the cold or hot dose as compared with prescription dose, it is necessary to analyse the skin dose occurring during the various plan of the breast cancer treatment. At our hospital, we want to apply various analyses using a diversity of dosimeters to the breast cancer treatment. Subjectss and Methods : In the study, the anthropomorphic phantom is used to find out the dose difference of the skin(draining site), scar and others occurring from the tangential treatment plan of breast cancer. We took computed tomography scan of the anthropomorphic phantom and made plans for the treatment planing using open and wedge, Field-in-Field, Dose fluence. Using these, we made a comparative analysis of the dose date points by using the Eclipse. For the dose comparison, we place the anthropomorphic phantom in the treatment room and compared the measurement results by using the TLD and MOSFET on the dose data points. Results : On the central point of treatment planing basis, the upward and downward skin dose measured by the MOSFET was the highest when the fluence was used. The skin dose of inner and outer was distinguished from the figure(5.7% ~ 10.3%) when the measurements were fulfilled by using TLD and MOSFET. The other side of breast dose was the lowest in the open beam, on the other hand, is highest in the Dose fluence plan. In the different kinds of treatment, the dose deviation of inner and outer was the highest, and so this was the same with the TLD and MOSFET measurement case. The outer deviation was highest in the TLD, and the Inner'was highest in the MOSFET. Conclusion : Skin dose in relation to the treatment plan was the highest in the planing using the fluence technique in general and it was supposed that the high dose had been caused by the movement of the MLC. There's some differences among the all the treatment planning, but the sites such as IM node occurring the lack of dose, scar, drain site are needed pay close attention. Using the treatment planning of dose fluence is good to compensate the lack of dose, but It increases the dose of the selective range rather than the overall dose. Therefore, choosing the radiotherapy technique is desirable in the lights of the age and performance of the patient.

• Restorative Dentistry and Endodontics
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• v.33 no.6
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• pp.537-544
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• 2008

Polymerase chain reaction (PCR) can detect bacteria more rapidly than conventional plate counting. However DNA-based assays cannot distinguish between viable and dead cells due to persistence of DNA after cells have lost their vitality. Recently, propidium monoazide (PMA) treatment has been introduced. The purpose of this study is to evaluate the applicability of the PMA treatment and real-time PCR method for cell counting in comparison with plate counting and to evaluate the antibacterial efficacy of 2% CHX on E. faecalis using PMA treatment in combination with real-time PCR. Firstly, to elucidate the relationship between the proportion of viable cells and the real-time PCR signals after PMA treatment, mixtures with different ratios of viable and dead cells were used. Secondly, relative difference of viable cells using PMA treatment in combination with real-time PCR was compared with CFU by plate counting. Lastly, antibacterial efficacy of 2% CHX on E. faecalis was measured using PMA treatment in combination with real-time PCR. The results were as follows : 1. Ct value increased with decreasing proportion of viable E. faecalis. 2. There was correlation between viable cells measured by real-time PCR after PMA treatment and CFU by plate counting until Optical density (OD) value remains under 1.0. However, viable cells measured by real-time PCR after PMA treatment have decreased at 1.5 of OD value while CFU kept increasing. 3. Relative difference of viable E. faecalis decreased more after longer application of 2% CHX.

• The Korean Journal of Pharmacology
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• v.30 no.3
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• pp.263-272
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• 1994

Since it was been reported that the depolarization-induced ACh release is inhibited by activation of presynaptic $A_1-adenosine$ heteroreceptor in hippocampus, a large body of experimental data on the post-receptor mechanism of this process has been accumulated. But, the post-receptor mechanism of presynaptic $A_1-adenosine$ receptor on the ACh release has not been clearly elucidated yet. Therefore, it was attempted to clarify the post-receptor mechanisms of the $A_1-adenosine$ receptor-mediated control of ACh release in this study. Slices from rat hippocampus were equilibrated with $^3H-choline$ and the release of the labelled products was evoked by electrical stimulation (3 Hz, 5 $VCm^{-1}$, 2ms, rectangular pulses), and the influence of various agents on the evoked tritium-outflow was investigated. Adenosine, in concentrations ranging from $0.3{\sim}300\;{\mu}M$, decreased the ACh release in a dose-dependent manner, without affecting the basal rate of release. The adenosine effects were significantly inhibited by $DPCPX\;(2\;{\mu}M)$, a selective $A_1-receptor$ antagonist. The responses to N-ethylmaleimide $(10&30{\mu}M)$, a SH-alkylating agent of G-protein, were characterized by increments of the evoked ACh-release and the basal release, and the adenosine effects were completely abolished by NEM pretreatment. PDB $(1{\sim}10\;{\mu}M)$, a specific protein kinase C (PKC) activator, increased, whereas PMB $(0.03{\sim}1\;mg)$, a PKC inhibitor, decreased the evoked ACh-release, and the adenosine effects were not affected by these agents. Nifedipine $(1\;{\mu}M)$, a $Ca^{2+}\;-channel$ blocker of dihydropyridine analogue, significantly inhibited the adenosine effect, but glibenclamide, a $K^+-channel$ blocker, did not. Finally, 8-bromo cyclic AMP $(100\;&\;300{\mu}M)$, a membrane-permeable analogue of cAMP, did not alter the ACh release, but adenosine effects were inhibited by pretreatment with large dose of 8-br-cAMP $(300\;{\mu}M)$. These results indicate that the decrement of the evoked ACh-release by $A_1-adenosine$ receptor is mediated by the G-protein, and nifedipine-sensitive $Ca^{2+}-channel$ and adenylate cyclase system are coupled partly to this effect, and that protein kinase C and glibenclamide-sensitive $K{^+}-channel$ are not involved in this process.

• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.175-182
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• 1993

As it has been reported that the depolarization-induced ACh release is modulated by activation of presynaptic $A_1-adenosine$ heteroreceptor in hippocampus and various lines of evidence indicate the adenosine effect is magnesium dependent, the present study was undertaken to delineate the role of endogenus adenosine as a modulator of hippocampal acetylcholine release in this study. Slices from the rat hippocampus were equilibrated with $[^3H]-choline$ and the release of the labelled product, $[^3H]-ACh$, was evoked by electrical stimulation(3Hz, $5\;V\;cm^{-1},$ 2ms, rectangular pulses), and the influence of various agents on the evoked tritium outflow was investigated. Adenosine, in concentrations ranging from $0.3\;to\;100\;{\mu}M$, decreased the $[^3H]-ACh$ release in a dose-dependent manner without changing the basal rate of release. $DPCPX(1{\sim}10{\mu}M)$, a selective $A_1-receptor$ antagonist, increased the $[^3H]-ACh$ release in a dose-related fashion with slight increase of basal tritium release. And the effects of adenosine were significantly inhibited by $DPCPX(2{\mu}M)$ treatment. CPCA, a specific $A_2-agonist$, in concentration ranging from $0.3\;to\;30\;{\mu}M$ decreased evoked tritium outflow with increase of basal rate of tritium release, and these effects were also abolished by $DPCPX(2{\mu}M)$ pretreatment. But, $CGS(0.1{\sim}10{\mu}M)$, a recently introduced potent $A_2-agonist$, did not alter the evoked tritium outflow. When the magnesium concentration of the medium was reduced to 0 mM, there was no change in evoked ACh release by adenosine. In contrast, increasing the magnesium concentration to 4 mM, the inhibitory effects of adenosine were significantly potentiated. These results indicate that $A_1-adenosine$ heteroreceptor is involved in ACh-release in the rat hippocampus and the inhibitory effects of adenosine mediated by $A_1-receptor$ is magnesium-dependent.

• The Korean Journal of Pharmacology
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• v.24 no.2
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• pp.233-240
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• 1988

A simple and selective isocratic HPLC method for the analysis of tissue polyamine contents is described and applied on the study of the changes of the hepatic polyamine contents after partial hepatectomy in male rats. The hepatic polyamines are extracted with 0.4 M perchloric acid containing 2 mM disodium EDTA, and then the extract is redissolved in 100 ul of 1 M sodium carbonate and incubated with 300 ul of FNBT-dimethylsulfoxide (1: 100) mixture. The N-2'-nitro-4'-trifluoromethylphenyl drivatives of polyamines are separated through a ERC-ODS column in an isocratic mode with an acetonitrile-water (80:20) mobile phase within 20 min. per a sample, while monitoring the effluent at 242 nm. This improved method which could detect subnanogram of each polyamines is highly specific and reproducible as evidenced by the application of it on the study of the changes of polyamine contents in the regenerating rat liver after partial hepatectomy.

• Korean Journal of Weed Science
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• v.12 no.1
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• pp.8-15
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• 1992

Arrowhead (Sagittaria trifolia L.), a perennial weed dominant in paddy field, is considerably difficult to control by herbicides. The investigation on the effects of environmental factors on emergence of arrowhead tuber can aid for controlling this weed. The results exmined were as follows : From the results of emergence characteristics at different levels of temperature, arrowhead tuber could germinated at 15$^{\circ}C$-40$^{\circ}C$. The optimal temperature for basal emergence was ranged from 25 to 30$^{\circ}C$. Basal emergence at 15$^{\circ}C$ and 20$^{\circ}C$ began at 56 and 12 days after tuber plantation, respectively and were later than those at the optimal temperature. At the different levels of shading, all the tested tubers could emerged. The days required for basal emergence at 25% and 50% shading plots were shorter than those at 70%, 80% and non-shading plots. The basal emergence was more effective under blue and clear films than any other phyto-selective materials. Some of arrowhead tubers could not emerged under green, red and yellow films. On the soil pH, the basal emergence was best at soil pH 6.0 and 7.0. At soil pH 4.0, 5.0 and 8.0, the required days for emergence were longer than those at soil pH 6.0 and 7.0 and some of tubers could not emerged. Arrowhead tubers more then 0.5 g showed the shorter shooting days than those less than 0.5 g. Tubers were able to emerge at water depth ranging from 0 to 20 cm. At 3 cm and 5 cm water depth, the required days for basal shooting were shorter than those at any other levels of water depth. The emergence of basals was best at molding depth of 0 cm, and the rates at 3 to 5 cm of plantation depth were decreased. At 10 cm plantation depth, the shooting rate was significantly decreased.

• Journal of Chest Surgery
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• v.37 no.7
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• pp.591-596
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• 2004

Recently, thoracic sympathicotomy for craniofacial hyperhidrosis (FH) is increasingly avoided contrast to palmar hyperhidrosis. We recently demonstrated that selective T2 sympathicotomy for FH in woman might be recommended because of differences of the postoperative satisfaction between man and woman. Therefore, this study was designed to analyze the postoperative long term results, evaluate the effectiveness of T2 sympathicotomy and establish the new strategy in treatment of FH in woman. Material and Method: From May 1998 to July 2001, 27 cases of FH in woman that were performed T2 sympathicotomy and minimum 2 years have passed since then at the follow up period. Among them, 20 cases were evaluated by telephone review and medical record. Bilateral sympathetic trunks were severed on the 2nd rib with 2mm thoracoscopic instruments. 7 patients combined with gustatory sweating (GS). Ages ranged from 25 to 62 (mean age, 46.4 years). Result: All patients were relieved of symptom immediately after operation. At postoperative 1 week, all patients were satisfied: 15 patients, “very satisfaction” and 5 patients, “relatively satisfaction”. However, during long term follow up period (from 25 to 63 months postoperatively), 9 patients (45%) were relatively satisfied, 8 patients (40%) complained that there was no difference of postoperative satisfaction and 3 patients (15%) complained of non satisfactory results (regret for surgery). 16 patients (80%) had complaint of uncomfortable feeling because of postoperative GS. Some degree of compensatory sweating (CS) had occurred in all patients: severe 10 patients (50%), severe but acceptable 6 patients (30%), and just conventional 4 patients (20%). The sites of CS were trunk, back, axilla and extremities. Conclusion: Thoracoscopic T2 sympathicotomy is relatively considerable method for FH in woman and the postoperative satisfaction depends on GS and the degree of individual adaptation for CS. Therefore, it is required that the prediction of preoperative risk factors for GS and CS and then careful selection of patients to increase the postoperative satisfaction, and the development of acceptable new treatment modalities.

• Journal of the Mineralogical Society of Korea
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• v.29 no.2
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• pp.59-71
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• 2016

To investigate the sorption characteristics of Cs, which is one of the major isotopes of nuclear waste, on natural zeolite chabazite, XRD, EPMA, EC, pH, and ICP analysis were performed to obtain the informations on chemical composition, cation exchange capacity, sorption kinetics and isotherm of chabazite as well as competitive adsorption with other cations ($Li^+$, $Na^+$, $K^+$, $Rb^+$, $Sr^{2+}$). The chabazite used in this experiment has chemical composition of $Ca_{1.15}Na_{0.99}K_{1.20}Mg_{0.01}Ba_{0.16}Al_{4.79}Si_{7.21}O_{24}$ and its Si/Al ratio and cation exchange capacity (CEC) were 1.50 and 238.1 meq/100 g, respectively. Using the adsorption data at different times and concentrations, pseudo-second order and Freundlich isotherm equation were the most adequate ones for kinetic and isotherm models, indicating that there are multi sorption layers with more than two layers, and the sorption capacity was estimated by the derived constant from those equations. We also observed that equivalent molar fractions of Cs exchanged in chabazite were different depending on the ionic species from competitive ion exchange experiment. The selectivity sequence of Cs in chabazite with other cations in solution was in the order of $Na^+$, $Li^+$, $Sr^{2+}$, $K^+$ and $Rb^+$ which seems to be related to the hydrated diameters of those caions. When the exchange equilibrium relationship of Cs with other cations were plotted by Kielland plot, $Sr^{2+}$ showed the highest selectivity followed by $Na^+$, $Li^+$, $K^+$, $Rb^+$ and Cs showed positive values with all cations. Equilibrium constants from Kielland plot, which can explain thermodynamics and reaction kinetics for ionic exchange condition, suggest that chabazite has a higher preference for Cs in pores when it exists with $Sr^{2+}$ in solution, which is supposed to be due to the different hydration diameters of cations. Our rsults show that the high selectivity of Cs on chabazite can be used for the selective exchange of Cs in the water contaminated by radioactive nuclei.