• YAKHAK HOEJI
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• v.45 no.6
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• pp.656-663
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• 2001

The quality of an intravenous immunoglobulin preparation (IVIG) is reflected by the degree of nonspecific activation of complements, the so-called anticomplementary activity (ACA). ACA of aggregates in IVIG was investigated using method by the European Pharmacopoeia and Clq-coated microtiter enzyme-linked immunosorbent assay (ELISA). Both the EP method and the ELISA method showed a dose response curve with the amount of complements bound increasing with the percentage content of aggregates in immunoglobulin standard. The correlation between the two tests was good (r=0.96, r=0.99). However, the correlation was not found when the ACA (EP method) of IVIG product was compared with its aggregate percentage. These results emphasize that the method of aggregate formation affects ACA and that estimation of the percentage distribution of aggregates by HPLC may not reflect ACA. In analysing WIG product for Clq binding activity test with the ELISA, the result by using Protein A-HRP correlated with aggregate percentage (r=0.84). But the correlation decreased (r=0.48) when the result used Protein A-AP(having poorer sensitivity than HRP) was compared with aggregate percentage. As a result, some variation between the two methods, due to differences in assay principles, is to be expected. However, ELISA technique has the advantage in that it is easier to perform, more precise and less subject to reagent variability, and is the more suitable screening method than HPLC analysis.

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.70-74
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• 2003

The heterogeneous bioluminescence immunoassay for digoxin was developed using photoprotein, native aequorin as a label and the site-directed immobilization technique based on avidin/biotin interaction. Aequorin is a bioluminescence protein, originally isolated from the jellyfish Aequoria Victoria and an attractive label in analytical applications because of sensitive detection due to virtually no background bioluminescent signal. Digoxin is a cardioactive drug, and its therapeutic level in serum is at low concentration with very narrow therapeutic index. The aequorin-digoxigenin conjugates were synthesized by the N-hydroxysuccinimide ester method and characterized in terms of bioluminescent residual activity. The resulting dose-response curve shows that the detection limit is $1.0\;{\times}\;10^{-10}\;M$ and a dynamic range is three orders of magnitude, which was obtained by $1.0\;{times}\;10^{-10}\;M$ conjugate and 0.9 μg/mL anti-digoxin antibody. Three structurally similar molecules to digoxin were examined for their cross-reactivity. None of these three compounds showed any crossreactivity with digoxin antibody employed in this study. Standard amounts of digoxin corresponding to the therapeutic range were spiked into the each serum solution. Study of the serum matrix effect indicated that correlation coefficient shows good agreement between luminescence light intensity between in buffer and in serum.

• KSBB Journal
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• v.26 no.2
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• pp.157-164
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• 2011

Five assays for anti-HBs were compared to improve potency test of Human lgG preparations. The three commercial EIA kits were optimized including dose response curve ranges and compared by conducting a co-laboratory study. After selecting the most reproducible EIA kit, methods comparison was performed with 22 samples in 5 different days. As a result, EIA (7.7 ${\pm}$ 5.3%) and MEIA (AxSYM: 3.7 ${\pm}$ 1.9%, IMx: 1.6 ${\pm}$ 0.8%) showed precision and accuracy (100.1 ${\pm}$ 12.6%). Therefore, the validated EIA assay was established and it is believed to be comparable to current MEIA.

• The Korean Journal of Applied Statistics
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• v.6 no.2
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• pp.383-391
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• 1993

Interaction between anti-cancer agents and various modulators of multidrug resistance in producing their joint effects are of fundamental interest in the chemtherapeutic treatment of cancer. We generate a dose-response curve for each combination of several anti-cancer agents and modulators based on an in-vitro experiment on each of several human cancer cell lines. We employ a log-linear model developed by Wahrendorf et al (1981) and Piegorsch et al (1988) to detect synergism among several compounds. We show two examples of the data analysis and their results. We believe that these results encourage further experiment in-vivo studies.

• Analytical Science and Technology
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• v.23 no.6
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• pp.537-543
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• 2010

Dopamine (DA) is an important neurotransmitter molecule of catecholamines. Its deficiency could lead to brain disorder such as Parkinson's disease and schizophrenia. Therefore, it is necessary to establish a suitable analytical technique with sensitivity and simplicity. A competitive enzyme-linked immunosorbent assay for DA has been optimized and characterized. Assay sensitivity is controlled by two factors in competitive immunoassay. One is a nature and concentration of competitor, and the other is those of binder, antibody. Thus, optimization was performed: BSA-DA conjugate and antibody-avidin conjugate were prepared by dual heterobifunctional coupling method using SATA and SMCC. Assay condition was optimized with $6.66\;{\mu}gmL^{-1}$ of BSA-DA and $4.17{\times}10^{-10}\;M$ of antibody-avidin conjugate. A dose-response curve was constructed, and a limit of detection and a dynamic range for DA were accomplished to $2.3{\times}10^{-2}\;{\mu}g\;mL^{-1}$ and four orders of magnitude ($1.0{\times}10^{-7}\;M$ to $1.0{\times}10^{-3}\;M$), respectively. Calibration curve was constructed on dynamic range and least-squares regression of this data gave the following relationship: absorbance = -0.1098 log[DA]+0.0353 ($R^2$ = 0.9956).

• Clinical and Experimental Reproductive Medicine
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• v.35 no.4
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• pp.309-317
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• 2008

Objectives: The aim of this study was to evaluate the usefulness of Anti-mullerian hormone (AMH) as a predictive marker for ovarian response and cycle outcome in IVF cycles. Methods: From Jan., to Aug., 2007, 111 patients undergoing IVF/ICSI stimulated by short or antagonist protocol were selected. On cycle day 3, basal serum AMH level and FSH level were measured. The correlation between basal serum AMH or FSH, and COH outcome was analyzed and IVF outcome was compared according to the AMH levels. To determine the threshold value of AMH for poor- and hyper-response, ROC curve was analyzed. Results: Serum AMH showed higher correlation coefficient (r=0.792, p<0.001) with the number of retrieved mature oocyte than serum FSH (r=-0.477, p<0.001). According to ovarian response, FSH and AMH leves showed significant differences among poor, normal, and hyperresponder. For predicting poor (${\leq}2$ oocytes) and hyperresponse (${\geq}17$ oocyets), AMH cut-off values were 0.5 ng/ml (the sensitivity 88.9% and the specificity 89.5%) and 2.5 ng/ml (sensitivity 85.7%, specificity 87.0%), respectively. According to the AMH level, patients were divided into 3 groups: low (${\leq}0.60\;ng/ml$), normal ($0.60{\sim}2.60\;ng/ml$), and high AMH (${\geq}2.60\;ng/ml$). The number of retrieved mature oocytes was significantly higher ($2.7{\pm}2.2$, $8.1{\pm}4.8$, $16.5{\pm}5.7$) and total gonadotropin dose was lower ($3530.5{\pm}1251.0$, $2957.1{\pm}1057.6$, and $2219.2{\pm}751.9\;IU$) in high AMH group (p<0.001). There was no significant difference in fertilization rates and pregnancy rates (23.8%, 34.0%, 37.5%) among the groups. Conclusions: Basal serum AMH level correlated better with the number of retrieved mature oocytes than FSH level, suggesting its usefulness for predicting ovarian response. However, IVF outcome was not significantly different according to the AMH levels. Serum AMH level presented good cut-off value for poor- or hyper-responders, therefore it could be useful in prediction of cycle cancellation, gonadotropin dose, and OHSS risk in IVF cycles.

• Journal of Chest Surgery
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• v.46 no.6
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• pp.402-412
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• 2013

Background: Moderate and severe hypothermia with cardiopulmonary bypass during aortic surgery can cause some complications such as endothelial cell dysfunction or coagulation disorders. This study found out the difference of vascular reactivity by phenylephrine in moderate and severe hypothermia. Methods: Preserved aortic endothelium by excised rat thoracic aorta was sectioned, and then down the temperature rapidly to $25^{\circ}C$ by 15 minutes at $38^{\circ}C$ and then the vascular tension was measured. The vascular tension was also measured in rewarming at $25^{\circ}C$ for temperatures up to $38^{\circ}C$. To investigate the mechanism of the changes in vascular tension on hypothermia, NG-nitro-L-arginine methyl esther (L-NAME) and indomethacin administered 30 minutes before the phenylephrine administration. And to find out the hypothermic effect can persist after rewarming, endothelium intact vessel and endothelium denuded vessel exposed to hypothermia. The bradykinin dose-response curve was obtained for ascertainment whether endothelium-dependent hyperpolarization factor involves decreasing the phenylnephrine vascular reactivity on hypothermia. Results: Fifteen minutes of the moderate hypothermia blocked the maximum contractile response of phenylephrine about 95%. The vasorelaxation induced by hypothermia was significantly reduced with L-NAME and indomethacin administration together. There was a significant decreasing in phenylephrine susceptibility and maximum contractility after 2 hours rewarming from moderate and severe hypothermia in the endothelium intact vessel compared with contrast group. Conclusion: The vasoplegic syndrome after cardiac surgery might be caused by hypothermia when considering the vascular reactivity to phenylephrine was decreased in the endothelium-dependent mechanism.

• Analytical Science and Technology
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• v.6 no.4
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• pp.349-357
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• 1993

Analytical methods of thromboxane $B_2(TXB_2)$ using various techniques of Fast Atom Bombardment mass spectrometry (FAB MS) were studied, static FAB condition was investigated to obtain linear response curve using docosanoic acid as a internal standard. For maximum sensitivity, a continuos-flow(CF-) FAB MS by selected-ion monitoring(SIM) with devised sample introduction system, has been developed to quantiate thromboxane $B_2$ in biological sample. Instrumental parameters affecting sensitivity, reproducibility has been studied. The method has been optimized with respect to the eluent, 0.75% glycerol(in EtOH v/v) and flow rate of $3.7{\mu}l/min.$ Under the condition, detection limits were below 10pg in SIM mode and a good linear relationship between dose and response was achieved.

• Nutritional Sciences
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• v.8 no.4
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• pp.226-230
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• 2005

To keep blood glucose levels as close to normal as possible is the major goal of diabetes mellitus treatment $\alpha$-Glucosidase is the enzyme that digests die1my carbohydrate and inhibition of this enzyme may suppress postprandial hyperglycemia. The methanol extract of Polygonum multiflorum Thunberg was tested for inhibitoty activity against $\alpha$-glucosidase in vitro and in vivo. Polygonum multiflorum Thunberg extract inhibited yeast $\alpha$-glucosidase activity in a concentration-dependent manner. Polygonum multiflorum Thunberg showed an $IC_{50}$ value of 0.48 mg/mL. The ability of Polygonum multiflorum Thunberg extract to lower postprandial glucose was studied in streptozotocin-induced diabetic rats. A starch solution (1 g/kg) with and without the methanol extract of Polygonum multiflorum Thunberg extract (500 mg/kg) was administered to diabetic rats by gastric intubation after an overnight fast A single oral dose of Polygonum multiflorum Thunberg extract significantly inhibited increases in blood glucose levels at 60 and 90 min (p<0.05) and significantly decreased incremental response areas under the glycemic response curve (p<0.05). These results suggest that Polygonum multiflorum Thunberg may have an antihyperglycemic effect by inhibiting $\alpha$-glucosidase activity in the animal model of diabetes mellitus.

• Nutrition Research and Practice
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• v.5 no.2
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• pp.107-111
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• 2011

The objective of this study was to investigate the hypoglycemic effects of quercetin (QE) in animal models of diabetes mellitus (DM). A starch solution (1 g/kg) with and without QE (100 mg/kg) or acarbose (40 mg/kg) was orally administered to streptozotocin (STZ)-induced diabetic rats after an overnight fast. Postprandial plasma glucose levels were measured and incremental areas under the response curve were calculated. To study the effects of chronic feeding of QE, five-week-old db/db mice were fed an AIN-93G diet, a diet containing QE at 0.08%, or a diet containing acarbose at 0.03% for 7 weeks after 1 week of adaptation. Plasma glucose and insulin, blood glycated hemoglobin, and maltase activity of the small intestine were measured. Oral administration of QE (100 mg/kg) or acarbose (40 mg/kg) to STZ-treated rats significantly decreased incremental plasma glucose levels 30-180 min after a single oral dose of starch and the area under the postprandial glucose response, compared with the control group. QE (0.08% of diet) or acarbose (0.03% of diet) offered to db/db mice significantly reduced both plasma glucose and blood glycated hemoglobin compared to controls without significant influence on plasma insulin. Small intestine maltase activities were significantly reduced by consumption of QE or acarbose. Thus, QE could be effective in controlling fasting and postprandial blood glucose levels in animal models of DM.