• Analytical Science and Technology
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• v.13 no.5
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• pp.616-623
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• 2000

The most common phthalate acid esters (8 compounds) and adipate were determined from water and sediment simultaneously. After liquid-liquid extraction with n-hexane for water and sonication extraction with dichloromethane for sediment, these were determined by the GC/MS with SIM mode. There were good linearities (above $R^2=0.993$) on the range of the 0.1-20 ng/ml (water) and 10-500 ng/g (sediment), and the detection limits of method were below 0.1 ng/ml and 10 ng/g for water samples and sediment samples, respectively. The method shows a good precision and accuracy for measurement of phthalates and adipate.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.2
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• pp.163-170
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• 1999

Objectives: The aims of this study are 1) to determine if GAST is a better indicator in predicting ovarian response to COH compared with patient's age or basal FSH level and 2) to evaluate its role in detecting abnormal ovarian response. Design: Prospective study in 118 patients undergoing IVF-ET using GnRH-a short protocol during May-September 1995. Materials and Methods: After blood sampling for basal FSH and estradiol $(E_2)$ on cycle day two, 0.5ml (0.525mg) GnRH agonist ($Suprefact^{(r)}$, Hoechst) was injected subcutaneously. Serum $E_2$ was measured 24 hours later. Initial $E_2$ difference $({\Delta}E_2)$ was defined as the change in $E_2$ on day 3 over the baseline day 2 value. Sixteen patients with ovarian cyst or single ovary or incorrect blood collection time were excluded from the analysis. The patients were divided into three groups by ${\Delta}E_2$; group A (n=30):${\Delta}E_2$<40 pg/ml, group B (n=52): 40 pg/ml${\leq}{\Delta}E_2$<100 pg/ml, group C (n=20): ${\Delta}E_2{\leq}100$ pg/ml. COH was done by GnRH agonist/HMG/hCG and IVF-ET was followed. Ratio of $E_2$ on day of hCG injection over the number of ampules of gonadotropins used ($E_2hCGday$/Amp) was regarded as ovarian responsiveness. Poor ovarian response and overstimulation were defined as $E_2$ hCGday less than 600 pg/ml and greater than 5000 pg/ml, respectively. Results: Mean age $({\pm}SEM)$ in group A, B and C were $33.7{\pm}0.8^*,\;31.5{\pm}0.6\;and\;30.6{\pm}0.5^*$, respectively ($^*$: p<0.05). Mean basal FSH level of group $A(11.1{\pm}1.1mlU/ml)$ was significantly higher than those of $B(7.4{\pm}0.2mIU/ml)$ and C $(6.8{\pm}0.4mIU/ml)$ (p<0.001). Mean $E_2hCGday$ of group A was significantly lower than those of group B or C, i.e., $1402.1{\pm}187.7pg/ml,\;3153.2{\pm}240.0pg/ml,\;4078.8{\pm}306.4pg/ml$ respectively (p<0.0001). The number of ampules of gonadotropins used in group A was significantly greater than those in group B or C: $38.6{\pm}2.3,\;24.2{\pm}1.1\;and\;18.5{\pm}1.0$ (p<0.0001). The number of oocytes retrieved in group A was significantly smaller than those in group B or C: $6.4{\pm}1.1,\;15.5{\pm}1.1\;and\;18.6{\pm}1.6$, respectively (p<0.0001). By stepwise multiple regression, only ${\Delta}E_2$ showed a significant correlation (r=0.68, p<0.0001) with $E_2HCGday$/Amp, while age or basal FSH level were not significant. Likewise, only ${\Delta}E_2$ correlated significantly with the number of oocytes retrieved (r=0.57, p<0.001). All four patients whose COH was canceled due to poor ovarian response belonged to group A only (Fisher's exact test, p<0.01). Whereas none of 30 patients in group A (0%) had overstimulation, 14 patients among 72 patients (19.4%) in group B and C had overstimulation (Fisher's exact test, p<0.01). Conclusions: These data suggest that initial $E_2$ difference after GAST may be a better prognostic indicator of ovarian response to COH than age or basal FSH level. Since initial $E_2$ difference demonstrates significant association with abnormal ovarian response such as poor ovarian response necessitating cycle cancellation or overstimulation, GAST may be helpful in monitoring and consultation of patients during COH in IVF-ET cycle.

• Korean Journal of Microbiology
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• v.35 no.1
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• pp.35-40
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• 1999

Effects of different molecular size fractions (100,000 nMW-0.1 $\mu\textrm{m}$m, 10,000 nMW-100,000 nMW and 1,000 nMW-'L0,000 nMW) of dissolved organic matter on the bacterial numbers and $\beta$-glucosidase activities in Lake Soyang were investigated. Even though the concentrations and characteristics of each fractions were different, bacterial growth curves of each fractioii were Lypical and similar. Each growth curve had highest peak of $1.1{\times}10^{7}$ cells $ml^{-1}$. But, the $\beta$-lucosidase activitics of each fraction were quite different. In high molecular weight fraction (HMW: 100,000 nMW-0.1 $\mu\textrm{m}$m), Vmax of Pglucosidase activity ranged from 550 to 1,160 nmol $1^{-1}$.$hi^{-1}$, but in low molecular weight f~action (1,000 nMW-10,000 nMW), that ranged from 1 to 14 om01 1$^[-1}$${-1}$

• The Korean Journal of Mycology
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• v.13 no.4
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• pp.243-247
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• 1985

Experiments were conducted to study effects of steroidal carbamate derivatives upon mycelial growth and aflatoxin production by Aspergillus flavus ATCC 15517. The basal medium was supplemented with various concentrations of these compounds and inoculated with spores. The developing cultures were incubated for 11 days at $28^{\circ}C$ without agitation. Aflatoxins were extracted with chloroform, separated by thin layer chromatography, and quantitated by ultraviolet spectrophotometry. At a concentration of 50 mg per 30 ml of medium., stigmasteryl-N-(2-chloroethyl) carbamate, cholesteryl- N - (2-chloroethyl) carbamate, $5{\alpha}-cholestan-3-one-oximino-N-(2-chloroethyl)$ carbamate and ${\beta}-sitosteryl-N-(2-chloroethyl)$ carbamate were the most effective in reducing aflatoxin production by Aspergillus flavus. However, cholest-4-ene-3-one-oximino-N-(2-chloroethyl) carbamate, at a concentration of 100 mg per 30 ml, significantly decreased aflatoxin production. There was no significant inhibition of mycelial growth by the addition of the various concentrations of these compounds.

• Biomolecules & Therapeutics
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• v.8 no.2
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• pp.119-124
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• 2000

We hypothesized that the extent of hypoxic injury would be involved in reduction of oxygen delivery to the tissue. Livers isolated from 18 hr-fasted rats were subjected to $N_2$-induced hypoxia or low flow hypoxia. Livers were perfused with nitrogen/carbon dioxide gas for 45min or perfused with normoxic Krebs-Henseleit bicarbonate buffer (KHBB) at low flow rates around 1 ml/g liver/min far 45min, which caused cells to become hypoxic because of insufficient delivery of oxygen. When normal flow rates(4 ml/g liver/min) of KHBB (pH 7.4, 37$^{\circ}C$, oxygen/carbon dioxide gas) were restored for 30min reoxygenation injury occurred. Lactate dehydrogenase release gradually increased in $N_2$-induced hypoxia, whereas it rapidly increased in low flow hypoxia. Total glutathione in liver tissue was not changed but oxidized glutathione markedly increased after hypoxia and reoxygenation, expecially in $N_2$-induced hypoxia. Similarly, lipid peroxidation in liver tissue significantly increased after hypoxia and reoxygenation in low flow hypoxia. Hepatic drug metabolizing functions (phase I, II) were suppressed during hypoxia, especially in $N_2$-induced hypoxia but improved by reoxygenation in both models. Our findings suggest that hypoxia results in abnormalities in drug metabolizing function caused by oxidative stress and that this injury is dependent on hypoxic conditions.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.182-182
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• 2011

We investigated the adsorption structures of serine on a Ge(100) surface by core-level photoemission spectroscopy (CLPES) in conjunction with density functional theory (DFT) calculations. The adsorption energies calculated using DFT methods suggested that four of six adsorption structures were plausible. These structures were the "O-H dissociated-N dative bonded structure", the "O-H dissociation bonded structure", the "Om-H dissociated-N dative bonded structure", and the "Om-H dissociation bonded structure" (where Om indicates the hydroxymethyl oxygen). These structures are equally likely, according to the adsorption energies alone. The core-level C 1s, N 1s, and O 1s CLPES spectra confirmed that the carboxyl oxygen competed more strongly with the hydroxymethyl oxygen during the adsorption reaction, thereby favoring formation of the "O-H dissociated-N dative bonded" and "O-H dissociation bonded" structures at 0.30 ML and 0.60 ML, respectively. The experimental results were corroborated theoretically by calculating the reaction pathways leading to the two adsorption geometries. The reaction pathways indicated that the "O-H dissociated-N dative bonded structure" is the major product of serine adsorption on Ge(100) due to comparably stable adsorption energy.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.560-565
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• 1999

The present work was conducted to investigate the drug susceptibility of microorganisms isolated from canine external ear canals. Antifungal susceptibility test of M pachydermatis (17 strains) was perfomed by agar dilution method, using 11 antifungal drugs including amphotericin B(A), nystatin(N), pimaricin(P), griseofulvin(G), bifonazole(B), clotrimazole(C), miconazole(M), econazole(E), ketoconazole(K), tolnaftate(T), 5-fluorocytosine(F). All isolates were highly sensitive to K, M, T(geometric mean MIC ; GM $MIC{\leq}0.16{\mu}g/ml$) but they weren't sensitive to P, F and G(GM $MIC{\geq}92.37{\mu}g/ml{\sim}{\geq}128{\mu}g/ml$). Antibacterial susceptibility test against 119 isolates of bacteria was performed by agar dilution method, using 9 antibacterial drugs including erythromycin(ET), chloramphenicol(CP), gentamycin(G), vancomycin(V), ampicillin(AP), amoxacillin(AX), chlortetracycline(CT), ciprofloxacin(CF), enrofloxacin(EF). All isolates of Staphylococcus spp(101 strains) were highly sensitive to EF, CF, G(GM MIC $0.33{\sim}1.47{\mu}g/ml$). In other gram positive cocci(4 strains), they were highly sensitive to EF, CF, V(GM MIC $1{\sim}4.76{\mu}g/ml$) and CT(GM MIC 1 UFL unit/ml). In gram positive rods(13 strains), they were highly sensitive to EF, CF, G(GM $MIC{\leq}0.19{\sim}1{\mu}g/ml$). In Pseudomonas aeruginosa(1 strain), it was highly sensitive to AX, EF, ET, CF(GM MIC $0.06{\sim}1{\mu}g/ml$) and CT(GM MIC 1 UFL unit/ml). All isolates weren't sensitive to AP(GM MIC 16~>$32{\mu}g/ml$).

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.4
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• pp.449-454
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• 1996

Cytogenetic effects of malathion and parathion, the organophosphorus pesticides were studied on goat lymphocytes in culture. The mitotic indices (% of blast cells + cells at metaphase) of goat lymphocytes showed corresponding decrease with the increase in dose of pesticides. Malathion had significant effect only at $150{\mu}g/ml$ or higher dosages while, parathion caused antimitotic effects even at the lowest dose ($5{\mu}g/ml$) tested. The clastogenic effects of malathion were significant ($p{\leq}0.05$) at $100{\mu}g/ml$. In higher doses, the effects were highly significant ($p{\leq}0.01$). The frequency of metaphase plates with chromosomal abnormalities were highest (22.0%) at $200{\mu}g/ml$. The incidences of chromosomal abnormalities were significant ($p{\leq}0.05$) in parathion treated series even at $5{\mu}g/ml$ dose level. At $10{\mu}g/ml$ or higher dose levels the difference between treatment groups and controls were more pronounced ($p{\leq}0.01$). Various types of chromosomal abnormalities were encountered in goat lymphocytes treated by malathion and parathion. However, the incidence of gaps, breaks, acentric fragments, dicentric chromosomes were higher than other types of structural and numerical abnormalities.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.579-584
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• 1999

The trace mineral status of cattle in the smallholder grazing areas of Sanyati and Chinamhora in Zimbabwe was evaluated during the rainy and dry seasons of 1994 and 1995. The evaluation was done in terms of mineral concentration in blood plasma. Plasma copper in calves, steers and cows in the dry season was; Sanyati: 0.55, 0.59, and 0.61; Chinamhora: 0.59, 0.58, and $0.60{\mu}g/ml$, respectively versus a normal of $0.65{\mu}g/ml$. In the rainy season, copper was deficient at both sites (averaging $0.56{\mu}g/ml$ and $0.59{\mu}g/ml$ at Sanyati and Chinamhora, respectively). Plasma selenium in the dry season was 0.017, 0.025, and $0.017{\mu}g/ml$ for calves, steers and cows, respectively at Sanyati versus a normal of $0.03{\mu}g/ml$ and therefore considered to be deficient. Iron, zinc and cobalt were found to be generally high and therefore unlikely to be deficient. Copper and selenium are recommended in salt licks in these environments.

• Toxicological Research
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• v.15 no.1
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• pp.75-78
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• 1999

In order to evaluate the mutagenic potential of Typhoid vaccine, 3 sets of mutagenicity tests were performed. In the reverse mutation test using Salmonella typhimurium TA98, TA100, TA1535 and TA1537, Typhoid vaccine did not increase the number of revertant at the doses of 100, 50, 25, 12.5, 6.25 $\mu\textrm{g}$/plate. I n chromosome aberration analysis using CHO cells were not found chromosomal aberration in different concentrations with or without metabolic activation at the doses of 0.25 mg/ml, 0.5mg/ml, 1mg/ml. In mouse micronucleus test, no significant increase in the occurrence of micronucleated polychromatic erythrocytes was observed in ICE male mice intramuscularly administered with Typhoid vaccine at the dosed of 0.1 mg/ml, 0.5 mg/ml, 1mg/ml. These results indicate that Typhoid vaccine gas no mutagenic potential in these in vitro and in vivo systems.