• Analytical Science and Technology
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• v.31 no.4
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• pp.161-170
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• 2018

The epidemic of disorders associated with synthetic stimulants, such as methamphetamine (MA) and amphetamine (AP), is a health, social, legal, and financial problem. Owing to the high potential of their abuse and addiction, reliable analytical methods are required to detect and identify MA, AP, and their metabolites in biological samples. Thus, a dilute-and-shoot liquid chromatography-tandem mass spectrophotometry (LC-MS/MS) was developed for simultaneous determination of MA, 4-hydroxymethamphetamine (4HMA), AP, and 4-hydroxyamphetamine (4HA) in urine. Urine sample ($100{\mu}L$) was mixed with $50{\mu}L$ of mobile phase consisting of 0.4 % formic acid and methanol and $50{\mu}L$ of working internal-standard solution. Aliquots of $8{\mu}L$ diluted urine was injected into the LC-MS/MS system. For all analytes, chromatographic separation was performed using a C18 reversed-phase column with gradient elution and a total run time of 5 min. The identification and quantification were performed by multiple reaction monitoring (MRM). Linear least-squares regression was conducted to generate a calibration curve, with $1/x^2$ as the weighting factor. The linear ranges were 2.0-200, 1.0-800, and 10-2500 ng/mL for 4HA and 4HMA, AP, and MA, respectively. The inter- and intraday precisions were within 6.6 %, whereas the inter- and intraday accuracies ranged from -14.9 to 11.3 %. The low limits of quantification were 2.0 ng/mL (4HA and 4HMA), 1.0 ng/mL (AP), and 10 ng/mL (MA). The proposed method exhibited satisfactory selectivity, dilution integrity, matrix effect, and stability, which are required for validation. Moreover, the purification efficiency of high-speed centrifugation was clearly higher than 6-15 % for QC samples (n=5), which was higher than that of the membrane-filtration method. The applicability of the proposed method was tested by forensic analysis of urine samples from drug abusers.

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.539-544
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• 2005

Purpose : The aim of this study was to investigate the pathophysiologic role of serum E-selectin, vascular endothelial growth factor(VEGF)-induced cell adhesion mollecule in Kawasaki disease(KD) and to look for the evidence of direct relationship between the plasma levels of soluble E-selectin and the incidence of coronary artery lesion(CAL). Methods : Changes in plasma levels of sE-selectin(n=98) over time were measured by enzyme-linked immunosorbent assay(ELISA) in 23 patients with acute KD and 25 age-matched febrile children. Results : Compared with control values, the peak levels of plasma sE-selectin were significantly elevated($mean{\pm}S.E$. : $22.89{\pm}12.53ng/mL$ vs $10.65{\pm}3.42ng/mL$, P=0.01) in KD. 5 patients with CAL, plasma sE-selectin levels before treatment were higher than in 18 patients without CAL($mean{\pm}S.E$. : $39.43{\pm}15.08ng/mL$ and $19.00{\pm}8.32ng/mL$, respectively; P=0.01). Plasma sE-selectin declined rapidly in the majority of KD patients regardless of the presence of CAL. Plasma sE-selectin levels after treatment and convalesent period were similar in KD patients with and without CAL. The plasma levels sE-selectin were correlated with those of white blood cell count(r=0.299, P<0.05), CRP(r=0.430, P<0.05), serum albumin(r=-0.483, P<0.05), serum protein(r=-0.502, P<0.05) and hemoglobin(r=-0.372, P<0.05) not with those of ESR, platelet, or duration of fever. There were significant differences in the initial level of serum sE-selectin between KD with and without CAL($mean{\pm}S.E$. : $39.44{\pm}15.08ng/mL$ vs. $19.00{\pm}17.18ng/mL$) in multivariated linear tests. Conclusion : Plasma sE-selectin levels were significantly higher in KD than in other febrile illness. Higher plamsa levels of sE-selectin may have potential as a predictor of CAL in patients with KD.

• Analytical Science and Technology
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• v.18 no.2
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• pp.147-153
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• 2005

Benzophenone (BP) which is one of endocrine disrupting chemicals is suspected to contaminate waters (river, lake and industrial drainage) and soils (ground soil and sediment). Analytical method for determination of BP in soil and water was developed by gas chromatography/mass spectrometry. Water sample (100 mL) was extracted with n-hexane, and soil (10 g) was extracted with methanol and n-hexane. Recovery for BP was >71.4% in water and 86.5-94.7% in soil with coefficient variation of less than 19.8%. Calibration curves showed a good linearity ($r^2$ >0.998). In water, soil and sediment collected at nation-wide sites, BP was detected at 5 sites among 43 water sites at the concentration range of 30-200 ng/L. No BP was found in the soil and sediment samples. It is suggested that this method will be useful to the determination of BP in the environmental matrices such as waters, soils and sediments in minute quantities.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.5
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• pp.361-365
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• 2009

Effects of quercetin, a kind of flavonoids, on the vasodilating actions were investigated. Among the mechanisms for quercetin-induced vasodilatation in rat aorta, the involvement with the $Ca^{2+}$ activated $K^+$ ($K_{Ca}$) channel was examined. Pretreatment with NE ($5\;{\mu}M$) or KCl (60 mM) was carried out and then, the modulation by quercetin of the constriction was examined using rat aorta ring strips (3 mm) at $36.5^{\circ}C$. Quercetin (0.1 to $100\;{\mu}M$) relaxed the NE-induced vasoconstrictions in a concentrationdependent manner. NO synthesis (NOS) inhibitor, NG-monomethyl-L-arginine acetate (L-NMMA), at $100\;{\mu}M$ reduced the quercetin ($100\;{\mu}M$)-induced vasodilatation from $97.8{\pm}3.7%$ (n=10) to $78.0{\pm}11.6%$ (n=5, p<0.05). Another NOS inhibitor, L-NG-nitro arginine methyl ester (L-NAME), at $10\;{\mu}M$ also had the similar effect. In the presence of both $100\;{\mu}M$ L-NMMA and $10\;{\mu}M$ indomethacin, the quercetin-induced vasodilatation was further attenuated by $100\;{\mu}M$ tetraethylammonium (TEA, a $K_{Ca}$ channel inhibitor). Also TEA decreased the quercetin-induced vasodilatation in endothelium-denuded rat aorta. Used other $K_{Ca}$ channel inhibitors, the quercetin-induced vasodilatation was attenuated by $0.3\;{\mu}M$ apamin (a SK channel inhibitor), but not by 30 nM charybdotoxin (a BK and IK channel inhibitor). Quercetin caused a concentration-dependent vasodilatation, due to the endotheliumdependent and -independent actions. Also quercetin contributes to the vasodilatation selectively with SK channel on smooth muscle.

• Journal of Nutrition and Health
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• v.42 no.6
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• pp.523-535
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• 2009

The aim of this study was to examine and compare the eating habits and dietary intake patterns of people with or without allergy by the survey during August-September, 2008. The 131 subjects aged 10'-50' (AG = allergy group, n = 62; NG = non-allergy group, n = 69) participated in this study. The questionnaire included general characteristics, dietary habits, and food frequency. Income level tended to be higher in AG than in NG, and AG had more pets and flower pots than NG (p < 0.01). In AG, most affected area of allergy was the skin and the subjects in AG experienced the mixed symptoms and more than 2 types of allergy. Family history of allergy was highly related with allergy of the subjects (AG: 66.1%, NG: 33.9%). Both groups did not exercise regularly, but frequency of alcohol drinking in AG was significantly higher than in NG (p < 0.01). AG skipped meals and had snacking more often than NG (p < 0.05). Most favorite snacks in AG were instant foods, fast foods, cookies, and ice cream (p < 0.05). Therefore, AG tended to consume more allergy-related foods than NG. Highly-consumed allergy-related foods were egg, pork, walnut, onion, tuna, shellfish, and kiwi (p < 0.05). Therefore, nutrition education and guidance is needed to establish good eating habits, food intakes, and life style in people having allergy.

• Journal of Nutrition and Health
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• v.50 no.1
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• pp.85-97
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• 2017

Purpose: This study was conducted to investigate dietary habits related to weight reduction and snack intake habits of $4^{th}$ to $5^{th}$ grade elementary students located in Jeju-si, Jeju, South Korea. Methods: The $4^{th}$ and $5^{th}$ grade elementary school students (total n = 234, equally matched numbers of normal weight children and overweight/obese children (n = 117/group)) were surveyed using a questionnaire and a 24-hour dietary recall method in Oct 2015. Results: The percentage of students who experienced reduced food intake to control weight was 26.3% in the normal weight group (NG) and 77.6% in the obese group (OG). Most frequently answered meal for reduced intake was snacks in the NG and dinner in the OG. Percentages of daily calorie intake among subjects were 17.2% for breakfast, 33.8% for lunch, 29.7% for dinner, and 19.3% for snacks. Frequency of snack intake was 2.1 times a week in NG and 1.6 times a week in OG, which showed a statistical difference between body weight groups. Types of snack foods were distinctly different depending on where children consumed them, although no difference was observed between NG and OG. In addition, snack intake level of low energy and nutrient-dense foods was significantly lower in the OG compared to the NG, whereas snack intake level of energy dense and low-nutritive foods was not different between the OG and NG. Conclusion: Taken together, snack intake level with consideration of frequency and amount of snack intake showed that children in the OG consumed significantly less low energy and nutrient-dense foods compared to the NG. Therefore, nutritional education for choosing healthy snack foods for children regardless of body weight status is crucial based on family-school links.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.628-634
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• 2016

Many pitchers suffer from various types of injury (distortion, sprain and so on). The rate of injury is increased if there are differences in strength between the extensor and flexor muscles when a joint movement is performed with maximum speed. However, there has been insufficient research into the injury caused by strength differences between the extensor and flexor muscles. Thus, the purpose of the study was to examine the effects of elbow ulnar collateral ligament injury on the maximal isometric strength in young baseball pitchers. The data collection was conducted for 2 weeks. The subjects (n=36) who participated in this study were placed into either the injury group (n = 18, IG) or normal group (n = 18, NG). The maximal isometric strength for the pectoralis major (PM), infraspintus (I), biceps brachii (BB), triceps brachii (TB), flexor carpi radialis (ECR) and extensor carpi radialis (FCR) muscles were determined by an isometric strength machine (K-DFX) and then the differences in strength were calculated by muscle group. All of the data were analyzed by SPSS 18.0 with the independent t-test. In the results, the maximal isometric strengths in the IG for the I (p=0.035), BB (p=0.031) and TB (p=0.041) were significantly lower than those in the NG, while that for the ECR (p=0.047) was significantly greater. In addition, the differences of the maximal isometric strength between the PM and I (p = 0.008), BB and TB (p = 0.002), and FCR and ECR (p = 0.032) in the IG were significantly greater than those in the NG. In conclusion, the differences in muscle strengths of the subjects in the IG were greater than those in the NG, which suggests that they might have a higher injury rate in the future. However, they might be able to recover from their injury and achieve better performance if the differences in strength were reduced by training.

• (The)Study of the Eastern Classic
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• no.67
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• pp.345-378
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• 2017

In the scriptures of "$Ch{\bar{u}}n-qi{\bar{u}}$(春秋)", the expression method of '$Ch{\bar{u}}n-w{\acute{a}}ng-zh{\bar{e}}ng-yu{\grave{e}}$(春王正月 : It's spring. It's the first month regulated by the king.)' was used as Jì-yuè-fǎ(紀月法 : the rules to determine the first month(正月)), the month of winter solstice was regarded as the first month of a year, and three years since then were named as $Ch{\bar{u}}n$(春 : spring). With regard to this "$Ch{\bar{u}}n-qi{\bar{u}}$"Wáng-lì("春秋"王曆 : the calendar regulated by the king of $Zh{\bar{o}}u$(周) dynasty in "$Ch{\bar{u}}n-qi{\bar{u}}$"), depending on whether Confucius(孔子) changed and recorded the names of the months and the season or not, there were three different arguments; the theory that 'Confucius changed the names of both the months and the season'(孔子改月 改時說), the view that 'Confucius changed the name of the season, not the names of the months'(孔子不改月 改時說), and then the theory that 'Confucius changed neither the names of the months nor the name of the season'(孔子不改月 不改時) since Song(宋) dynasty. The first view was taken by $Hh{\acute{u}}-{\bar{a}}n-gu{\acute{o}}$(胡安國) and $C{\grave{a}}i-ch{\acute{e}}n$(蔡沈), and the second theory was mentioned by Chéng-yí(程?) and Zhū-zǐ(朱子). The advocates of the third view had become remarkable since Ming(明) dynasty, and one of representatives was Wàng-yáng-míng(王陽明). All of them based their arguments on ancient scriptures and Confucian legal books, and there were cases of taking the same records as the support for different opinions. Confucius' so-called 'Chūn-qiū-bǐ-fǎ(春秋筆法 : the method to describe historical facts by making clear discrimination between right and wrong)' and '$Sh{\grave{u}}-{\acute{e}}r-b{\grave{u}}-zu{\grave{o}}$(述而不作 : the attitude to succeed virtuous men's achievements and only explain and describe them not creating and adding new contents)' could come from thoughts of $Z{\bar{u}}n-w{\acute{a}}ng$(尊王 : to respect the king with the virtues of benevolence, righteousness, propriety, wisdom and sincerity). Therefore, even though Confucius is assumed to have been the writer of "$Ch{\bar{u}}n-qi{\bar{u}}$(春秋)", whether he actually changed and recorded the names of the months and the season in the calendar used in "$Ch{\bar{u}}n-qi{\bar{u}}$" is doubtful. These theories on Confucius's intervention in the calendar of "$Ch{\bar{u}}n-qi{\bar{u}}$" hadn't been discussed as conflicting in reality until Tang(唐) dynasty.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.55-59
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• 2000

A specific and sensitive sandwich enzyme-immunoassay (EIA) using Avidin-Biotin complex was developed for the measurement of GTH II levels in pituitary content and pituitary cell culture medium of the rainbow trout-(Oncorhpchus mykiss). Biotin-salmon GTH II rabbit IgG (sefondary antibody) wai purified by a protein A sepharose affinity chromatography column and that was biotinylated by using Biotin-N-hydroxysuccinimide ofter (BNHS). Non-biotin salmon GTH II rabbit IgG (first antibody) was obtained only through a protein A sepharose affinity chromatography column. The assay was performed by the so-called 'sandwich' method using a microtiter plate, A dose-response curve was obtained between $0.12 to 125 ng/ml$ of salmon GTH II. The displacement curves for pituitary extraction and pituitary cell culture medium of testosterone-treated rainbow trout were Parallel to the standard curie. The intra-assay and inter-assay coefficients of variation (CV) were $8.2{\%} (N=5) and 12.5{\%} (N=6)$, respectively, This assay system was used to measure the amount of GTH II that accumulated in the culture medium of dispersed pituitary cells in testosterone-treated immature rainbow trout, The accumulation was increased with the amount or salmon gonadotropin-releasing hormone. GTH II values determined by the present method were well correlated with those determined by radioimmunoassay. As a result, this assay system was found to be suitable for the measurement of GTH II for pituitary extraction and pituitary culture medium in many salmonid fishes.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1554-1561
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• 2014

Present study analyzed the changes in peripheral blood testosterone concentrations and testicular cytogram in relation to age and semen quality in crossbred males. Three different age groups of crossbred males viz. bull calves (6 months, n = 5), young bulls (15 months, n = 5) and adult bulls (4 to 6 years, n = 8) were utilized for the study. Testicular fine needle aspiration cytology technique was used to quantify testicular cytology and their indices. Peripheral blood testosterone concentrations were measured using enzyme-linked immunosorbent assay method. Semen samples collected from adult bulls were microscopically evaluated for quality parameters. Mean peripheral blood testosterone concentrations in bull calves, young bulls and adult bulls were $2.28{\pm}0.09ng/mL$, $1.42{\pm}0.22ng/mL$ and $5.66{\pm}1.08ng/mL$ respectively, and that in adult bulls were significantly different (p<0.01) from young bulls and bull calves. There was no significant difference between the proportion of different testicular cells in bull calves and young bulls. Between young and adult bulls, significant differences (p<0.01) were observed in the proportion of spermatocytes, spermatozoa, and sperm: Sertoli cell ratio. The proportions of Sertoli cells showed a significant difference (p<0.01) between the three age groups. The number of primary spermatocytes had a positive correlation with peripheral blood testosterone concentrations in bull calves (r = 0.719, p<0.01). Number of Sertoli cells per 100 germ cells was negatively correlated with blood testosterone concentration in young bulls (r = -0.713, p<0.01). Among different semen parameters in adult bulls, ejaculate volume (r = 0.790, p<0.05) had positive relationship, and sperm motility had significant negative correlation (r = -0.711, p<0.05) with testosterone concentrations. The number of Sertoli cells and Sertoli cell index had a positive correlation with various semen quality parameters (p<0.001). Results of the present study conclude that number of Sertoli cells and Sertoli cell index are good indicators of semen quality, but peripheral blood testosterone concentrations may not have a direct relationship with various seminal attributes in crossbred bulls.