• Journal of Periodontal and Implant Science
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• v.35 no.1
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• pp.111-121
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• 2005

Coronary heart disease is the leading cause of mortality in adult population. Whereas the association between periodontal disease and coronary heart disease (CHD) are controversial, recent studies reported the association between periodontal disease and acute myocardial infarction or prognosis of CHD. This study was aimed to investigate the relationship between periodontal disease and angiographically defined CHD, and acute myocardial infarction, and the prognosis of treated CHD. Patients under the age of 60 who had undergone the diagnostic coronary angiography were enrolled in this study, Subjects were classified as positive CHD (+CHD, n=37) with coronary artery stenosis more than 50% in at least one of major epicardial arteries, and negative CHD (-CHD, n=20) without stenosis. After recording the number of missing teeth, periodontal disease status was measured by means of plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), and clinical attachment level (CAL), Positive CHD subjects were classified into acute myocardial infarction group (AMI), and non-AMI with angina pectoris and old myocardial infarction. Six months postoperatively, positive CHD subjects were followed and had undergone the coronary angiography again. Even though there was no significant difference in the periodontal parameters and status between positive CHD and negative CHD, some periodontal parameters, such as mean probing depth and proportion of sites with probing depth greater than 4mm or 6mm were significantly different between AMI and Non-AMI(p<0.05). There was no significant difference in the periodontal parameters according to in angiographically follow-up status. These results indicate that periodontal disease may be associated with the occurrence of acute myocardial infarction.

• Journal of environmental and Sanitary engineering
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• v.16 no.1
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• pp.91-101
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• 2001

In order to propose a optimum method increasing accuracy and reproducibility in analysis of urine lead levels, we compared matrix modifier addition method and microwave digestion method. The results were as follows ; 1. Where the concentration of $Pd(NO_3)_2$(matrix modifier) was $50mg/{\ell}$, and ashing temperature was $900^{\circ}C$, the results were optimum. In case of matrix modifier addition method, the average coefficient of variation (CV) of normal man was 24.1%, and lead worker was 7.9%. The average urine lead levels of standard were $10.42\mu{g}/{\ell}$ and $19.89\mu{g}/{\ell}$ , the accuracies compared to reference values were 97.0% and 92.6%, respectively. 2. Microwave digestion temperature($160~180^{\circ}C$), time(15~25min) and the ratio of urine/ashing acid(1:1~4:1) did not significantly affect lead absorbance and background absorbance. Therefore we set up a optimum analytical conditions as follows: temperature, $160^{\circ}C$; time, 15min; the ratio of urine/ashing acid, 4:1. after samples were digested by the above analytical conditions, lead absorbance and background absorbance was measured at $450^{\circ}C$ as ashing temperature. The average coefficient of variation (CV) of normal man was 12.4%, and lead worker was 6.2%. The average urine lead levels of standard urine were $10.66\mu{g}/{\ell}$ and $23.31\mu{g}/{\ell}$, the accuracies compared to reference values were 99.3% and 103.9%, respectively. From the results, we suggest that microwave digestion method is a more favorable method than matrix modifier addition method because of easiness to reduce organic matter, possibility to analysis at low temperature and accuracy.

• Korean Journal of Veterinary Research
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• v.46 no.4
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• pp.315-322
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• 2006

Ethanol abuse is associated with liver injury, neurotoxicity, modulation of immune responses, and increased risk for cancer, whereas moderate ethanol consumption exerts protective effects against liver injury. However, the underlying signal transduction mechanisms of insulin-like growth factors (IGFs) which play an important regulatory role in various metabolism mechanisms are not well understood. We investigated the effects of ethanol-induced p42/44 activity on IGF-I secretion, IGF-I receptor and IGFBP-1 secretion using radioimmunoassay and western blotting in primary cultured rat hepatocytes. The p42/44 activity, IGF-I secretion and IGF-I receptor activity significantly accelerated compared to control at 10 and 30 min after 200 mM ethanol treatment, but then it became suppressed at 180 min. In contrast, IGFBP-1 secretion was inhibited compared to control at 30 min after 200 mM ethanol treatment, but increased at 180 min. The IGF-I secretion, IGF-I receptor and p42/44 activity at 30 min after 200 mM ethanol treatment accelerated with increasing ethanol concentration but IGFBP-1 secretion inhibited (p<0.05). The increased IGF-I secretion, inhibited IGFBP-1 secretion and IGF-IR activity by ethanol-induced temporal p42/44 activity at 30 min after ethanol treatment was blocked by treatment with PD98059. Alcohol dehydrogenase (ADH) inhibitor, 4-methylpyramazole blocked the changes of IGF-I secretion, IGFBP-1 secretion, and IGF-IR activity by ethanol-induced p42/44 activity at 30 and 180 min. Taken together, these results suggest that ethanol is involved in the modulation of IGF-I and IGFBP-1 secretion and IGF-IR activity by p42/44 activity in primary cultured rat hepatocytes. In addition, changing of p42/44 activity by ethanol was caused with ADH.

• Biomolecules & Therapeutics
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• v.14 no.1
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• pp.50-55
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• 2006

The objective of the study was to evaluate the bioequivalency between the $Rozid^{TM}$ Tablet (Ilhwa Pharm. Co., Ltd.) as a test formulation and the $Rulid^{TM}$ Tablet (Handok Pharm. Co., Ltd) as a reference formulation. Twenty-four healthy male volunteers were administered the formulations by the randomized Latin square crossover design, and the plasma samples were determined by a high performance liquid chromatography (HPLC) with fluorescence detector. $AUC_t,\;C_{max}\;and\;T_{max}$ were obtained from the time-plasma concentration curves, and log-transformed $AUC_t\;and\;C_{max}$ and log-untransformed $T_{max}$ values for two formulations were compared by statistical tests and analysis of variation. $AUC_t$ was determined to be $63.30{\pm}25.57{\mu}g.hr/ml$ for the test formulation and $64.02{\pm}29.27mg.hr/ml$ for the reference formulation. The mean values of $C_{max}$ for the test and reference formulations were $5.07{\pm}2.14\;and\;5.53{\pm}2.60{\mu}g/ml$, respectively. The $AUC_t,\;and\;C_{max}$ ratios of the test $Rozid^{TM}$ Tablet to the reference $Rulid^{TM}$ Tablet were -1.12% and -8.32%, respectively, showing that the mean differences were satisfied the acceptance criteria within 20%. The results from analysis of variance for log-transformed $AUC_t,\;and\;C_{max}$ indicated that sequence effects between groups were not exerted and 90% confidence limits of the mean differences for $AUC_t,\;and\;C_{max}$ were located in ranges from log 0.80 and log 1.25, satisfying the acceptance criteria of the KFDA bioequivalence. The RozidTM Tablet as the test formulation was considered to be bioequivalent to the RulidTM Tablet used as its reference formulation, based on $AUC_t,\;and\;C_{max}$ values.

• The Korean Journal of Nuclear Medicine
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• v.32 no.4
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• pp.391-395
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• 1998

Purpose: Chitin and chitosan are nontoxic natural chelators that chelate radiostrontium effectively. The purpose of this study was to compare radiostrontium chelation of chitin and chitosan with that of well known chemical chelators, namely EDTA and DTPA. Materials and Methods: The chelaton rates of chitin, chitosan, EDTA and DTPA were compared using a column chromatography method (Sephadex G-25M, Sweden). Three kinds of chitins and four kinds of chitosans were used. All of them were water soluble. Results: Phosphated chitosan showed the highest chelation yield of 97% at pH 7. All of chitins, chitosans, EDTA and DTPA showed chelation yield of more than 90% independent of varing pH level. Conclusion: Chitin and chitosan have similar chelation rate as compared with EDTA and DTPA.

• Archives of Pharmacal Research
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• v.26 no.12
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• pp.1055-1060
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• 2003

Lysophosphatidic acid (LPA) is a well-known mitogen in various cell types. However, we found that LPA inhibits melanocyte proliferation. Thus, we further investigated the possible signaling pathways involved in melanocyte growth inhibition. We first examined the regulation of the three major subfamilies of mitogen-activated protein (MAP) kinases and of the Akt pathway by LPA. The activations of extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) were observed in concert with the inhibition of melanocyte proliferation by LPA, whereas p38 MAP kinase and Akt were not influenced by LPA. However, the specific inhibition of the ERK or JNK pathways by PD98059 or D-JNKI1, respectively, did not restore the antiproliferative effect. We next examined changes in the expression of cell cycle related proteins. LPA decreased cyclin $D_1 and cyclin D_2$ levels but increased $p21^{WAF1/CIP1}$ (p21) and $p27^{KIP1}$ (p27) levels, which are known inhibitors of cyclin-dependent kinase. Flow cytometric analysis showed the inhibition of DNA synthesis by a reduction in the S phase and an increase in the $G_0/G_1$ phase of the cell cycle. Our results suggest that LPA induces cell cycle arrest by regulating the expressions of cell cycle related proteins.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.5
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• pp.467-472
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• 2015

Histone deacetylase (HDAC) has been recognized as a potentially useful therapeutic target for cardiovascular disorders. However, the effect of the HDAC inhibitor, trichostatin A (TSA), on vasoreactivity and hypertension remains unknown. We performed aortic coarctation at the inter-renal level in rats in order to create a hypertensive rat model. Hypertension induced by abdominal aortic coarctation was significantly suppressed by chronic treatment with TSA (0.5 mg/kg/day for 7 days). Nicotinamide adenine dinucleotide phosphate-driven reactive oxygen species production was also reduced in the aortas of TSA-treated aortic coarctation rats. The vasoconstriction induced by angiotensin II (Ang II, 100 nM) was inhibited by TSA in both endothelium-intact and endothelium-denuded rat aortas, suggesting that TSA has mainly acted in vascular smooth muscle cells (VSMCs). In cultured rat aortic VSMCs, Ang II increased p66shc phosphorylation, which was inhibited by the Ang II receptor type I ($AT_1R$) inhibitor, valsartan ($10{\mu}M$), but not by the $AT_2R$ inhibitor, PD123319. TSA ($1{\sim}10{\mu}M$) inhibited Ang II-induced p66shc phosphorylation in VSMCs and in HEK293T cells expressing $AT_1R$. Taken together, these results suggest that TSA treatment inhibited vasoconstriction and hypertension via inhibition of Ang II-induced phosphorylation of p66shc through $AT_1R$.

• Journal of Astronomy and Space Sciences
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• v.26 no.1
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• pp.31-46
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• 2009

An Unscented Kalman Filter (UKF) for estimation of the attitude and rate of a spacecraft using only magnetometer vector measurement is developed. The attitude dynamics used in the estimation is the nonlinear Euler's rotational equation which is augmented with the quaternion kinematics to construct a process model. The filter is designed for small satellite in low Earth orbit, so the disturbance torques include gravity-gradient torque, magnetic disturbance torque, and aerodynamic drag torque. The magnetometer measurements are simulated based on time-varying position of the spacecraft. The filter has been tested not only in the standby mode but also in the detumbling mode. Two types of actuators have been modeled and applied in the simulation. The PD controller is used for the two types of actuators (reaction wheels and thrusters) to detumble the spacecraft. The estimation error converged to within 5 deg for attitude and 0.1 deg/s for rate respectively when the two types of actuators were used. A joint state parameter estimation has been tested and the effect of the process noise covariance on the parameter estimation has been indicated. Also, Monte-Carlo simulations have been performed to test the capability of the filter to converge with the initial conditions sampled from a uniform distribution. Finally, the UKF performance has been compared to that of the EKF and it demonstrates that UKF slightly outperforms EKF. The developed algorithm can be applied to any type of small satellites that are actuated by magnetic torquers, reaction wheels or thrusters with a capability of magnetometer vector measurements for attitude and rate estimation.

• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.2 s.17
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• pp.81-87
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• 2004

Semiconductor thick film gas sensors based on tin oxide are fabricated and their gas response characteristics are examined for four simulant gases of chemical warfare agent (CWA)s. The sensing materials are prepared in three different sets. 1) The Pt or Pd $(1,\;2,\;3\;wt.\%)$ as catalyst is impregnated in the base material of $SnO_2$ by impregnation method.2) $Al_2O_3\;(0,\;4,\;12,\;20\;wt.\%),\;In_2O_3\;(1,\;2,\;3\;wt.\%),\;WO_3\;(1,\;2,\;3\;wt.\%),\;TiO_2\;(3,\;5,\;10\;wt.\%)$ or $SiO_2\;(3,\;5,\;10\;wt.\%)$ is added to $SnO_2$ by physical ball milling process. 3) ZnO $(1,\;2,\;3,\;4,\;5\;wt.\%)$ or $ZrO_2\;(1,\;3,\;5\;wt.\%)$ is added to $SnO_2$ by co-precipitation method. Surface morphology, particle size, and specific surface area of fabricated sensing films are performed by the SEM, XRD and BET respectively. Response characteristics are examined for simulant gases with temperature in the range 200 to $400^{\circ}C$, with different gas concentrations. These sensors have high sensitivities more than $50\%$ at 500ppb concentration for test gases and also have shown good repetition tests. Four sensing materials are selected with good sensitivity and stability and are fabricated as a sensor array A sensor array Identities among the four simulant gases through the principal component analysis (PCA). High sensitivity is acquired by using the semiconductor thick film gas sensors and four CWA gases are classified by using a sensor array through PCA.

• Korean Journal of Medicinal Crop Science
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• v.20 no.1
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• pp.27-35
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• 2012

This study was conducted to investigate changes in composition of ginsenosides and color of processed ginsengs prepared by different steaming-drying times. Processed ginsengs were prepared from white ginseng with skin by 9-time repeated steaming at $96^{\circ}C$ for 3 hours and followed by hot air-drying at $50^{\circ}C$ for 24 hours. As the times of steaming processes increased, lightness (L value) decreased and redness (a value) increased in color of ginseng powders. Crude saponin contents and ginsenosides compositions in processed ginsengs prepared by different steaming-drying times were investigated using the HPLC method, respecively. Crude saponin contents according to increasing steaming-drying times decreased in some degree. In the case of major ginsenosides, the contents of $Rb_1$, $Rb_2$, Rc, Rd, Rf, Re, $RG_1$, Re were decreased with increase in steamimg times, but those of $Rh_1$, $Rg_3$, $Rk_1$ were increased after especially 3 times of steaming processes. Interestingly, in black ginseng were prepared by 9 times steaming processes, the content of ginsenoside $Rg_3$ was 8.20 mg/g, approximately 18 times higher than that (0.46 mg/g) in red ginseng. In addition, the ratio of the protopanaxadiol group and protopanaxatiol group (PD/PT) were increased from 1.9 to 8.4 due to increasing times of steamming process.