• Bulletin of the Korean Chemical Society
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• 제21권5호
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• pp.483-486
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• 2000

A method is described for the fluorimetric determination of nickel, based on the formation of $Ni(II)-\alpha-(2-Benzimidazolyl)-\alpha'$, $\alpha''$ -(N-5-Nitro-2-Pyridylhydrazone)-toluene complex in the presence of a non-ionic surfactant. The complex has practically no fluorescence in the absence of surfactant, but the addition of Triton X-100 makes possible the fluorimetric determination of low concentrations of Ni(II) as it enhances the fluorescenceintensity of the complex by up to about 5-fold. This method is very sensitive and selectrive for the direct determination of nickel ion. The optimum conditions are a Triton X-100 concentration of 2.0 mL(5.0%, v/v) and pH $9.0\pm0.2(ammonium$ chloride-ammonia buffer). The fluorescence is measured at 337 nm of emission wavelength under 300 nm of excitation wavelength. The fluorescence intensity is a linear function of the concentration of Ni(II) in the range 5-70 ng/mL, and the detection limit is 2.0 nm/mL. The proposed method has been successfully applied to the determination of trace amounts of Ni(II) in food and human hair samples.

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1158-1164
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• 2011

5-Methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT), a psychoactive tryptamine derivative, is a hallucinogenic drug of abuse. In this study, 5-OH-DIPT and its metabolites were identified and the quantitative method was developed and validated by using hydrophilic interaction chromatography-tandem mass spectrometry (HILICMS/MS). Chromatographic separation was achieved on an Atlantis HILIC silica column ($5{\mu}m$, $100{\times}2.1\;mm$). The metabolites of 5-MeO-DIPT in rat urine were characterized via Q1 scanning and product ion scanning. As a consequence, 5-MeO-IPT, 5-OH-DIPT, 6-OH-5-MeO-DIPT and their glucuronide conjugates were detected and identified as the metabolites of 5-MeO-DIPT. Subsequently, a quantitative method for 5-MeO-DIPT and its major metabolites, 5-MeO-IPT and 5-OH-DIPT, was developed in multiple reactions monitoring (MRM) mode. The calibration curves for all analytes evidenced good linearity over the concentration range of 1-1000 ng/mL with linear correlation co-efficients ($r^2$) in excess of 0.99. The intra- and inter-day accuracy and precision were 92.2-110.2% and 1.5-9.9%, respectively.

• 대한환경공학회지
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• 제22권11호
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• pp.1977-1983
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• 2000

천연가스를 사용하는 복합화력발전소에서 발생되는 질소산화물(NOx)에 대한 귀금속촉매(Pt/Zeolite)의 활성을 디젤유를 환원제로 사용하여 파일럿 규모의 선택적촉매환원장치(selective catalytic reduction)에서 환원제 주입량, 반응온도, 공간속도에 따라 고찰하였다. 시험결과, 디젤유의 주입량을 증가시킬수록 NOx의 전환율은 증가하였으며 C/N비(C/N비: 배기가스 중에 포함된 NOx의 분자수에 대한 환원제 탄소 원자수의 비) 5.5 이상에서는 일정한 전환율을 유지하였다. NOx 전환율에 대한 반응온도의 영향을 알아본 결과, 온도가 증가함에 따라 NOx의 전환율이 증가하여 $190^{\circ}C$의 온도에서 최고 50%의 전환율을 보였다. 7,200/hr~27,000/hr의 범위에서 NOx 전환율에 대한 공간속도의 영향은, 18,500/hr까지 일정한 전환율을 유지하였으며 그 이상에서는 감소하였다. 이상의 결과에서 디젤유를 환원제로 사용하는 질소산화물 제거를 위한 SCR 공정의 적용 가능성을 확인할 수 있었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권4호
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• pp.323-330
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• 2004

Estrogen may promote osteoblast/osteocyte viability by limiting apoptotic cell death. We hypothesize that hsp27 is an estrogen- regulated protein that can promote osteoblast viability by increasing osteoblast resistance to apoptosis. The purpose of this study was to determine the effect of estrogen treatment and heat shock on $TNF{\alpha}$ - induced apoptosis in the MC3T3-E1 cell line. Cells were treated with 0 - 100 nM $17{\beta}$ estradiol (or ICI 182780) for 0 - 24 hours before heat shock. After recovery, apoptosis was induced by treatment with 0 - 10 ng/ml TNF${\alpha}$. Hsp levels were evaluated by Northern and Western analysis using hsp27, hsp47, hsp70c and hsp70i - specific reagents. Apoptosis was revealed by in situ labeling with Terminal Deoxyribonucleotide Transferase (TUNEL). A 5 - fold increase in hsp27 protein and mRNA was noted after 5 hours of treatment with 10 - 20 nM $17{\beta}$ estradiol prior to heat shock. Increased abundance of hsp47, hsp70c or hsp70i was not observed. TUNEL indicated that estrogen treatment also reduced (50%) MC3T3-E1 cell susceptibility to $TNF{\alpha}$ - induced apoptosis. Treatment with hsp27-specific antisense oligonucleotides prevented hsp27 protein expression and abolished the protective effects of heat shock and estrogen treatment on $TNF{\alpha}$- induced apoptosis. Hsp27 is a determinant of osteoblast apoptosis, and estrogen treatment increases hsp27 levels in cultured osteoblastic cells. Hsp27 contributes to the control of osteoblast apoptosis and may be manipulated by estrogenic or alternative pathways for the improvement of bone mass.

• 한국음향학회지
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• 제14권1호
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• pp.65-72
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• 1995

국어 종성을 시간축에서 거꾸로 들었을 때 우리 귀에 들리는 음가에 대하여 청취실험을 실시하였다. 이를 위해 우리말 자음의 이름 14개를 발음하여 데이타를 수집하고 이를 시간축 상에서 역으로 출력시켜 스피커를 통해서 청취하여 들리는 대로 음가를 기록하였다. 역파형은 청취시에 초성으로 변하며 종성에 촛점을 맞추어 종성이 초성으로 변했을 때 어떻게 들리는가를 알아보고 조음 방법 및 조음 위치에 따라 분석하였다. 그 결과 대표 종성 7개 중에서 종성 ㄴ 은 초성 ㄴ으로 들렸으며 종성 ㄹ은 초성 ㄹ, 종성 ㅁ은 초성 a으로 들려서 ㄴ, ㄹ, ㅁ은 종성의 음가가 초성과 같다는 것을 확인할 수 있으며 종성 ㄷ은 초성 ㄴ처럼 들리고 종성 ㅇ은 ㅁ처럼 들리며 종성 ㄱ, ㅂ은 초성으로 들었을 때 음가를 갖지 않는 다는 것을 실험을 통해 확인하고 이를 조음 원리에 의해 해석하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.452-455
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• 2004

In this paper, investigations of the SAMs(self-assembled monolayers) of a thiol-fuctionalized viologen derivatives, $V_8SH$ and $SH_8V_8SH$, where, V is N,N'-dialkylbipyridinium (i.e. a viologen group), have been carried out by elucidate voltammetry date. The redox reactions are highly reversible and can be cycled many times without significant side reaction, which has been known as a nano-gram order mass detector through resonant frequency change self-assembly process of the viologen has been investigated with $QCM({\Delta}F)$. The assembling process of the $V_8SH$ and $SH_8V_8SH$ monolayers can be finished completely in about 1 hour. The measured frequency shift for $V_8SH$ and $SH_8V_8SH$ were about 351 and 172 Hz, respectively. From these values, we calculated that the mass adsorbed $V_8SH$ and $SH_8V_8SH$ were about 375 and 183 ng. We believe that this mass loss is caused by the simultaneous loss of the anions present within the monolayer for charge compensation of the viologen dications and some solvent.

• Parasites, Hosts and Diseases
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• 제54권6호
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• pp.769-775
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• 2016

This retrospective case-control study explored the factors associated with anaphylactic shock during surgery for cystic echinococcosis (CE) at the First Affiliated Hospital of Xinjiang Medical University between October 2008 and September 2013. Patients who suffered from anaphylactic shock (n=16) were age-matched 3:1 to patients who did not (n=43). Multivariate analysis suggested that IL-4 levels (odds ratio=1.096; 95% confidence interval=1.015-1.185; P=0.02) and cyst size (odds ratio=3.028, 95% confidence interval=1.259-7.283, P=0.013) were independently associated with CE-induced perioperative anaphylactic shock. Using the receiver operating characteristic (ROC) curves and a cut-off value of 415.7 ng/ml, IL-4 showed an area under the ROC (AUC) of 0.926, sensitivity of 75.0%, and specificity of 97.7%. Using a cut-off value of 7.8 cm, cyst size showed an AUC of 0.828, sensitivity of 81.3%, and specificity of 76.7%. In conclusion, results suggest that levels of IL-4 and cyst size were independently associated with echinococcosis-induced perioperative anaphylactic shock. These results could help identifying patients with echinococcosis at risk of anaphylactic shock in whom appropriate prophylaxis could be undertaken.

• Nutrition Research and Practice
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• 제10권3호
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• pp.328-335
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• 2016

BACKGROUND/OBJECTIVES: Vitamin D plays an important role in the etiology of gestational diabetes mellitus (GDM). This study evaluated the effect of vitamin D supplementation on metabolic indices and hs-C-reactive protein (CRP) levels in GDM patients. SUBJECTS/METHODS: The study was a randomized, placebo-controlled, double-blinded clinical trial. Seventy-six pregnant women with GDM and gestational age between 24-28 weeks were assigned to receive four oral treatments consisting of 50,000 IU of vitamin $D_3$ (n = 38) or placebo (n = 38) once every 2 weeks for 2 months. Fasting blood glucose (FG), insulin, HbA1c, 25-hydroxyvitamin D, lipid profile, hs-CRP, and homeostasis model assessment-insulin resistance (HOMA-IR) were measured before and after treatment. Independent and paired t-tests were used to determine intra- and intergroup differences, respectively. ANCOVA was used to assess the effects of vitamin D supplementation on biochemical parameters. RESULTS: Compared with the placebo group, in the vitamin D group, the serum level of 25-hydroxyvitamin D increased (19.15 vs. -0.40 ng/ml; P < 0.01) and that of FG (-4.72 vs. 5.27 mg/dl; P = 0.01) as well as HbA1c (-0.18% vs. 0.17%; P = 0.02) decreased. Improvements in the lipid profiles were observed in the vitamin D group, but without statistical significance. Significant increases in concentrations of hs-CRP, FG, HbA1c, total cholesterol, and LDL cholesterol were observed in the placebo group. No significant change in fasting insulin and HOMA-IR was observed in either group. CONCLUSIONS: In GDM patients, vitamin D supplementation improved FG and HbA1c but had no significant effects on lipid profile or hs-CRP.

• Archives of Pharmacal Research
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• 제22권1호
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• pp.48-54
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• 1999

These studies were designed to examine the differential effect of nitric oxide (NO) and cGMP on glutamate neurotransmission. In primary cultures of rat cerebellar granule cells, the glutamate receptor agonist N-methyl-D-aspartate (NMDA) stimulates the elevation of intracellular calcium concentration ($[Ca^{2+}]_i$), the release of glutamate, the synthesis of NO and an increase of cGMP. Although NO has been shown to stimulate guanylyl cyclase, it is unclear yet whether NO alters the NMDA-induced glutamate release and ${[Ca^{2+}]}_i$ elevation. We showed that the NO synthase inhibitor, NG-monomethyl-L-arginine (NMMA), partially prevented the NMDA-induced release of glutamate and elevation of ${[Ca^{2+}]}_i$ and completely blocked the elevation of cGMP. These effects of NO on glutamate release and [Ca2+]i elevation were unlikely to be secondary to cGMP as the cGMP analogue, dibutyryl cGMP (dBcGMP), did not suppress the effects of NMDA. Rather, dBcGMP slightly augmented the NMDA-induced elevation of ${[Ca^{2+}]}_i$ with no change in the basal level of glutamate or ${[Ca^{2+}]}_i$. The extracellular NO scavenger hydroxocobalamine prevented the NMDA-induced release of glutamate providing indirect evidence that the effect of NO may act on the NMDA receptor. These results suggest that low concentration of NO has a role in maintaining the NMDA receptor activation in a cGMP-independent manner.

• 동아시아식생활학회지
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• 제17권2호
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• pp.183-191
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• 2007

The purpose of this study was to investigate the relationship between serum leptin, lipids, bone metabolism markers and nutrient intakes of obese middle-school girls compared to those of normal subjects. Each subject was assigned to either the normal(n=22) or obese groups(n=25) according to their BMI. The subjects were asked for their general characteristics and nutrient intakes using a questionnaire and 24-hr recall method. The serum leptin, lipids and osteocalcin(bone metabolism marker) were measured using blood analyses. The average ages of the subjects in the normal and obese groups were 13.9 and 14.0 years, respectively. The average weight(p<0.001) and BMI(p<0.001) of normal group were significantly lower than those of the obese group. The plant protein intake of the girls in the obese group was lower than that of the normal group(p<0.01). The levels of serum leptin in the obese and normal groups were 18.0 and 10.0 ng/mL, respectively(p<0.001). The serum LDL-cholesterol(p<0.01) and triacylgeride(p<0.05) of the obese girls were higher than those in the normal group. Also, the serum osteocalcin(bone formation marker) in the obese group was lower than that in the normal group(p<0.001). The BMI was negatively correlated to osteocalcin(p<0.001), but positively correlated to the serum leptin(p<0.001). The serum osteocalcin was also positively correlated to the plant protein intake(p<0.05). In conclusion, the excessive increase in weight and % body fat in middle-school students appeared to have a negative impact on bone health. Based on these results, further studies will be needed on the effects of bone metabolism markers, obesity and nutrient intakes for proper bone health.