수용액중에서 분산제가 초미립자의 분산과 응집에 미치는 영향

황성태,장경환,정경락 全北大學校 1996 論文集 Vol.42 No.-

The dispersibility of ultrafine particles is affected by the kinds and amount of dispersants. The optimum dispersive condition for ultrafine particles was determined from the measurement of the zeta-potential and particle size distribution at concentrations. The zeta-potential and the particle size distribution of dilute suspension was measured using the light scattering method. Also, the influence of kinds and amount of diapersants on the dispersion of TiO_2 fine particle in water is discussed by the DLVO theory. In particular it is shown that the optimum concentration of a dispersant obtained experimentally is approximately in accordance with the concentration of the dispersant showing the maximum total potential energy(V_Tmax) calculated from the DLVO theory which is coincident with the one showing the maximum zeta-potential.

사회복귀시설의 현황과 전망

황태연,이종국,고영,이주호,지성학 용인정신의학연구소 1997 용인정신의학보 Vol.4 No.1

축산시설의 입지특성 분석 : 안성시 미양면을 중심으로

황한철,전우정,이남호,홍성구,김진태 안성산업대학교 1998 論文集 Vol.30 No.2

It is necessary to evaluate the location suitability of livestock facilities to guide reasonable livestock. The evaluation system could help plan new livestock facilities in rural areas. The assessment was performed based on location characteristics of livestock facilities such as land utilization around livestock facilities, size of livestock facilities, water and drainage condition, accessibility and distance from roads, floor condition, distance from village and house, direction of livestock facilities, ventilation facilities, animal Waste treatment, and so forth. In this study, location characteristics of livestock facilities were showed each location factors using statistical analysis.

MR Spectroscopy로 진단한 Leigh 병 1례

황성욱,황태규,김용우 인제대학교 2006 仁濟醫學 Vol.27 No.-

Leigh syndrome is a progressive and degenerating central nerve system disease with symmetrically localized necrotic changes on the both gray and white matter, called subacute necrotizing encephalopathy. The causes of this disease have been revealed that defect of various enzymes (pyruvate dehydrogenase, repiratory complex Ⅰ, Ⅳ, Ⅴ, etc.)related to mitrochondrial carbonate metabolism and energy generating mechanisms. The clinical course is variable, and symptoms such as non-specific- seizure, respiratory failure, nystagmus, decreased muscle tone, developmental delay, vomiting and lethargy etc. appeared. And the diagnostic tool is not clear, so the diagnosis is difficult. Brain MRI and MR spectroscopy have been used to diagnose Leigh syndrome. We experienced 1 case of Leigh syndrome with typical MR, MR spectroscopic findings. MRI shows the lesions on midbrain, both basal ganglia, caudate nucleus, putamen, periaqueductal area, and periventricular white matter. MR spectroscopic findings showing high lactate peak were appropriate to Leigh disease. The patient is a 16-month-old girl with generalized weakness, and died within 1 month after first admission on our hospital. We report this case with typical MR spectroscopic findings.

대식세포의 Pro-inflammatory cytokine 생산에 대한 세포디짐의 효과

주성수,강희철,원태준,황광우,이도익 중앙대학교 약학연구소 2003 약학 논총 Vol.17 No.-

Cefodizime, a third cephalosporine, was originally developed for use in infectious disease as an advanced antibiotics. Cefodizime has also been known to play a meaningful role in activating natural killer properties of immune cells as well as enhancing immunological parameters such as phagocytosis. Furthermore, as the infection can result in remarkable changes for homeostatic mediators, it is expected that cefodizime may initiate the strong immuno- modualtory effect. In the present work, we investigated whether cefodizime has a biphasic effect of anti-bacteria and immunomodulation via macrophage. For the study, we isolated mouse peritoneal macrophages and treated with cefodizime 10㎍/㎖, 50㎍/㎖, 100㎍/㎖, IFN-v 10U/㎖.+LPS l㎍/㎖ Cells were then incubated for 4, 8, 12, and 24hrs to analysis the expression of IL-1, IL-6, IL-12 mRNA from macrophages. The results showed that cytokines were expressed more than that of control in a time-dependent manner and 100㎍/㎖ cefodizime group showed the greatest expression as much as the positive control (IFN-v+LPS)showed at 24h. In conclusion, cefodizime can play a significant role for the expression of pro-inflammatory cytokines, IL-1, IL-6, and IL-12 in earlier stage so that macrophages and other immune cells can response to the infectious substances, immediately. Moreover, when such pro-inflammatory cytokines are increased, we can also expect that the enhancement of cell-cell interaction of NK cell, CTL and B cell by cefodizime can affect the immunomodulatory effect along with its major role in anti-bacterial effect.

고등학교 육상 선수와 일반 학생의 콜레스테롤 조성에 관한 비교 연구

남태호,황영성,김귀원 釜山大學校 附設 體育科學硏究所 1993 體育科學硏究所 論文集 Vol.9 No.-

Background : This study was designed to investigate on cholesterol composition between athletes and common students. Method : The subjects of this study are nine athletes and random selectional ten students in B high school. BMI, % Fat, TC, HDL-c and LDL-c were measured and compared, and correlation and difference between each variable was investigated. Results : Between the player group and the control group, BMI has significant difference (p<.05), and in the control group, BMI and % Fat have significant correlation. In the player group, there is a significant correlation between TC and TC/HDL-c (P<.01), and in the control group, there is a very significant correlation (P<.001). The correlation between LDL-c and LDL-c/HDL-c in the player group is significant (P<.01), and one of the control group is very significant. (P<.001) There is no significant correlation of HDL-c, LDL-c, TC/HDL-c, LDL-c/HDL-c in the player group, on the other side, there is each significant correlation by the level of P<.05, P<.001, P<.001 in the control group. There is no statistically significant difference in HDL-c, LDL-c between the player and the control group, but from the mean of them, the player group has higher level of HDL-c (0.3 mg/dl), and lower level of LDL-c (0.9 mg/dl) than control group. And the player group has higher 5.0 mg/dl TC than the control group. nificant.(P<.001)

骨格筋 Protein Methylase Ⅱ에 關한 硏究

洪承元,郭相太,林圭,黃炳斗 충남대학교 의과대학 지역사회의학연구소 1988 충남의대잡지 Vol.15 No.2

Protein methylase Ⅱ (S-adenosy-L-methionine : protein-carboxyl 0-methyltransferase) has been, purifed 6,600-fold from bovine skeletal muscle and characterized. The purification procedures involved ammonium sulfate fractionation, Sephadex G-75 chromatography, S-adenosyl-L-homocysteine-Sepharose 4B chromatography, and hydroxyapatite chromatography. The enzyme showed an optimal pH around 6.0. It was heat-labile, being inactivated by heattreatment at 60℃ for 6 minutes. However, storage of the enzyme at -20℃ in the presence of 10% glycerol prevented the activity loss for 6 months. The apparent Km for S-adenosyl-L-methionine was 2.86 × 10 exp (6) M. Copper(Cu^2+) ion was potent noncompetitive inhibitor, the activity being completely inhibited b) 0.25 mM Cu^2+ and 1 mM Zn^2+. Most of the activity loss by copper and zinc ions were recovered by the addition of ethylenediamine tetracetate. The enzyme was also completely inhibited by 0.5 mM phydroxymercuribenzoate, which could be reversed by the addition of 10 mM 2-mercaptoethanol. The molecular weight of the enzyme was 24,000, as determined by Sephadex G-75 chromatography. Histone IIA, immunoglobulin A and soybean trypsin inhibitor were efficiently carboxylmethylated by the enzyme. Sarcoplasmic reticulum(SR) and sarcolemma(SL) of the skeletal muscle were also efficiently carboxylmethylated by the enzyme at a rate of 0.96 and 0.63 pmolesl mg protein/min of 3^H-CH_3, incorporation, respectively. Polyacrylamide gel electrophoresis of the carboxylmethylated SR and SL revealed multiple carboxylmethylated subfactions : SR resolved into the subfractions with molecular weight 100,000, 55,000, 22,000 and 14, 400, and SL into the subfractions with molecular weight 48,000, 22,000 and- 14, 400. Of these subfractions those with Mr=22, 000 were most strongly carboxylmethylated. Endogenous cAMP-dependent phoshorylation of SR occurred in the subfractions with Mr=55, 000, Mr=27, 000 and Mr=~14, 400, of which the fraction with Mr=27, 000 was most strongly phosphorylated. When SR was carboxylmethylated, the endogenous cAMP-dependent phosphorylation was decreased. SR exhibited relatively high Ca^2+-ATPase activity and oxalate-facilitated ATP-dependent 45^Ca^z+uptake. The carboxylmethylation and cAMP-dependent phosphorylation of SR increased the Ca^2+TATPase activity by 15% and by 29%, respectively. However, cAMP-dependent phosphorylation of SR which had been previously carboxylmethylated led to only 23% increase in the Ca^2+-ATPase activity. Both the carboxylmethylation and cAMP-dependent phosphorylation enhanced the steady-state rate as well as the initial rate of ^45Ca^2+-uptake. Kinetic analysis showed that the apparent Km and Vmax of Ca^2+ for ATP-dependent Ca^2+-uptake were 45μM and 35 nmoles/mg protein, respectively. Both the carboxylmethylation and cAMP-dependent phosphorylation of SR decreased the Km and increased the Vmax for the Ca^2+-uptake. These results suggest that protein methylase II might have some regulatory role in the calcium transport of sarcoplasmic reticulum.

olanzapin과 Risperidone의 급성 및 만성 투여기가 흰쥐 전전두피질의 Dopamine 농도에 미치는 영향

문선근,정영철,은홍배,황익근,박태원 大韓神經精神醫學會 2002 신경정신의학 Vol.41 No.1

항정신병약물들이 전전두피질의 세포외 dopamine 농도에 미치는 영향은 이 약물들의 음성 증상에 대한 효과와 관련이 있는 것으로 보고 되고 있다. 따라서 본 연구에서는 최근 국내에서 많이 사용되고 있는 olanzapine과 risperidone을 흰쥐에 급성 및 만성 투여를 한 후, 이들 약물들이 전전두피질의 세포외 dopamine 농도에 미치는 영향을 알아보고자 하였다. 샘플은 생체 내 뇌 미세투석법(in vivo brain microdialysis)을 이용하여 얻었고 샘플내 dopamine의 농도는 전기화학적 검출법(electrochemical detection : ECD)을 사용하는 고압액체크로마토그라피(high pressure liquid chromatography : HPLC)로 측정하였다. 그 결과는 다음과 같다. 1) Olanzapine과 risperidone의 급성 투여는 전전두피질 부취의 세포외 dopamine 농도를 증가시켰으며 증가의 정도는 용량 의존적이었다. 2) Olanzapine과 risperidone의 급성 투여에 의해 전전두피질 부위에 나타난 세포외 dopamine 농도의 최고치는 두 약물간에 유의한 차이가 없었다. 3) Olanzapine과 risperidone의 만성 투여는 전전두피질 부위의 세포외 dopamine 농도를 증가시켰으나 그 증가의 정도가 급성 투여에 비해 모두 감소하는 내성 현상이 보였다. 4) Olanzapine과 risperidone의 만성 투여에 의해 전전두피질 부위에 나타나는 세포외 dopamine 농도의 최고치는 olanzapine과 risperidone에 비해 유의하게 높았다. 이상의 결과들은 Olanzapine과 risperidone의 음성 증상에 대한 임상적 효과가 이들 약물이 전전두피질의 세포외 dopamine 농도를 증가시키는 효과와 관견이 있음을 제시한다. Object : It is reported that the effect of antipsychotics on the extracellular dopamine levels in the prefrontal cortex is related to the their effect on the negative symptoms. Therefore, we investigated the acute and chronic effects of olanzapine and risperidone on the extracellular dopamine concentrations in the prefrontal cortex of rat. Samples were obtained using in vivo brain microdialysis. Method : Dopamine levels in the samples were measured by high pressure liquid chromatography with electrochemical detection. Results : 1) Both the acute treatment of olanzapine and risperidone increased the extracellular dopamine concentrations in the prefrontal cortex, dose-dependently. 2) There was a no significant difference in the maximal change of the extracellular dopamine concentrations in the prefrontal cortex induced by the acute treatment of olanzapine and risperidone. 3) Both the chronic treatment of olanzapine and risperidone also increased the extracellular dopamine concentrations in the prefrontal cortex, but they showed the tolerance effect that the degree of increase was smaller than that of the acute treatment. 4) As for the maximal changes of the extracellular dopamine concentrations in the prefrontal cortex induced by the chronic treatment of planzapine and risperidone, the effect of the former was greater than that of the latter. Conclusion : These results suggest that the effects of olanzapine and risperdone on the negative symptoms are related to the increased extracellular dopamine concentrations in the prefrontal cortex induced by these drugs.

인적오류에 의한 항공사고 분석

장성록,황진태,배동철 釜慶大學校 2001 釜慶大學校 論文集 Vol.6 No.-

This study aimed to investigate the human-related causes of aircraft accidents and present the basic data for developing human-error prevention program. Peterson's model of accident causation and Cooper's model of safety culture were applied to analyze the severe causes of aircraft accidents for last 10 years. For analyzing the causes of aircraft accidents, expert's opinion method was adopted. The analyses showed that the overload and decision error were major causes of aircraft accidents. The causes and backgrounds of human error were found with respect to human, tasks, organization.

탄소섬유시트로 보강된 RC보의 휨거동에 대한 실험적 연구

김성도,황태일 경성대학교 공학기술연구소 2002 공학기술연구지 Vol.9 No.-

The flexural behavior of a strengthened beam, that is a reinforced concrete beam with externally bonded fiber sheets, was theoretically and experimentally investigated. A rectangular beams having a width of 20㎝, depth of 30㎝, and effective depth of 25㎝ were tested. Carbon fiber sheets with a width of 15㎝ are externally bonded at the bottom face of the beam. From the experimental results, a variety of failure modes have been identified, ranging from crushing of the concrete to delamination of the fiber sheets. The paper presents the results of experimental and analytical studies concrening the flexural behavior of RC beams with fiber sheets. Included in the study are the effect of the amount of carbon fiber sheets varying from 1 to 4 plies on the beam strength enhancement and the valid estimation of the rupture strain of the fiber sheets.