• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.2
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• pp.189-197
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• 1994

Analytic methods for Cr(VI) level in industrial hygienic field were suggested by the National Institute for Occupational Safety and Health(NIOSH method 7600, 7604). There were growing needs for measurement of Cr(III) and Cr(VI) levels simultaneously. Two analytical methods were suggested to determine Cr(III) and Cr(VI) levels simultaneously. The one is method by using reversed phase high peformance liquid chromatography(HPLC) and the other is by using ion exchange HPLC. The purpose of this work was to evaluate the usefulness of these two analytic methods. For the difference of ionic charges of Cr(III)-ethylendiamine tetraacetic acid(EDTA) chelate and $CrO_4{^-2}$, we could detect them simultaneously by ion exchange HPLC. Also, we attempted to determine the levels of Cr(III) and Cr(VI) chelated with sodium diethyldithiocarbamate(NaDDTC) by using reversed phase HPLC. The confirmation of Cr(III) and Cr(VI) were checked by fraction collector and nameless atomic absorption spectrometer. The optimal conditions for the formation of Cr(III)-EDTA chelate were two hours incubation period with pH 5. Cr(III)-EDTA and Cr(VI) in EDTA solution were successfully separated by anion exchange column using $Na_2CO_3/NaOH$ mixture as mobile phase. Peaks of Cr(III)-EDTA and Cr(VI) in EDTA were identified at 5 minutes and 7 minutes of retention time respectively by the ion exchange HPLC. The formation of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were twelve hours incubation period. Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were separated by reversed phase column using methanol and water mixture as mobile phase. Peaks of Cr(VI)NaDDTC and Cr(III)-NaDDTC chelates were identified at 13 minutes and 26 minutes of retention time respectively by the reversed phase HPLC. Due to reduction of Cr(VI) to Cr(III), it seems to be not suitable for simultaneous determination of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates by reversed phase HPLS. Simultaneos determination of Cr(III) and Cr(VI) by ion exchange HPLC was more accurate and simple method.

• Journal of Technologic Dentistry
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• v.29 no.2
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• pp.197-211
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• 2007

With the development of orthodontics and increasing concerns on physical appearance, the number of patients has been steadily increasing. It is quite important not only to make effective cure plans and accurate diagnoses but also to have a thorough grasp of patients' malocclusion types and their occurrence frequency, in addition to patients' personality in order to cure the patients appropriately. This study is based on 946 malocclusion patients who had visited Chong-A Dental Hospital from 1999 to 2004 and investigated their aspects of malocclusion and characteristics of their gender, age and residence. The results are as follows. 1. The number of patients per year had been decreased until 2001, after which year the number had fluctuated. The number was the largest in 1999, 169 and the smallest in 2001, 140. Female occupied 68.0% of the total, twice as many as male, 32.0%) 2. Based on the Angle's classification, 19 or over year - old group was the largest of the total, 59.3% and 6 or younger year - old group, the smallest, 0.5%. The 19 or over year old group was less than a half of the total (47.4%) in 2003 and there were no patients who belonged to the 6 or younger year - old group in 2003 and 2004. 3. Distributions on the types of malocclusion have shown that 39.9 % of the total are in the Class I, the largest, 31.0% in the Class I and 29.2 in the Class II, the smallest. 1) The number of the ClassI was 73, the largest, that of the Class III being 35, the smallest in 1999. On the whole, the number of the Class I accounted for the largest part of the total. 2) The number of male patients in the Class II was the smallest, generally being the largest in the Class I. In case of female, that of the Class III was the smallest. 3) Based on the age, the Class I was the highest in between 7 and 13 age group, the Class III the lowest. The Class I occupied the largest around 40%. 4) In the shape of physiognomy, the meso occupied the largest part among all the Class, of which the Class II was the highest, 64.2%. The bracy was the largest in the Class I, and the dolicho in the Class III. 5) In the profile, the convex shape was the largest in the Class I and II, and especially in the Class II, over 3/4 of the total, 75.4%. In contrast, the direct shape was the largest in the Class III and the sunken shape occupied 33.3%, which was nearly ten times more than the case of the Class I and III. 6) In the asymmetry of physiognomy, the number of patients of the Class IIIwas the largest, 34.1% and that of the Class II, the smallest, 19.5%. It was found that about one fourth of the malocclusion patients were under the asymmetry of physiognomy. 4. In the distribution of patients' residence, 81.4% were from the Seoul Metropolis and 48.2% from Gangnam-Gu where Chong-A Dental Hospital is located and Seocho-Gu and Songpa-Gu which are adjacent to Gangnam-Gu.

• Biomedical Science Letters
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• v.13 no.3
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• pp.197-206
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• 2007

P2X receptors are membrane-bound ion channels that conduct $Na^+,\;K^+$, and $Ca^{2+}$ in response to ATP and its analogs. There are seven subunits identified so far ($P2X_1-P2X_7$). $P2X_2$ receptors are known to be expressed in a wide range of organs including brains and adrenal grands. PC12 cells are originated from adrenal grand and differentiated by nerve growth factor or pituitary adenylate cyclase activating poly peptide (PACAP). Previous studies indicate that $P2X_2$ receptor activation in PC12 cells couples to $Ca^{2+}-dependent$ release of catecholamine and ATP. It is known that acidic pH potentiates ATP currents at $P2X_2$ receptors. This leads to a hypothesis that $P2X_2$ receptors may play an important role in PC12 cell differentiation, one of the characteristics of which is neurite outgrowth, induced by the hormones under lower pH. In the present study, we isolated several clones which potentiate neurite outgrowth by PACAP in acidic pH (6.8), but not in alkaline pH (7.6). RT-PCR and electrophysiology data indicate that these clones express only functional $P2X_2$ receptors in the absence or presence of PACAP for 3 days. Potentiation of neurite outgrowth resulted from PACAP (100 nM) in acidic pH is inhibited by the two P2X receptor antagonists, suramin and PPADS ($100\;{\mu}M)$ each), and exogenous exprerssion of ATP-binding mutant $P2X_2$ receptor subunit ($P2X_2[K69A]$). However, acid sensing ion channels (ASICs) are not involved in PACAP-induced neurite outgrowth potentiation in lower pH since treatments of an inhibitor of ASICs, amyloride ($10\;{\mu}M$), did not give any effects to neurite extension. The vesicular proton pump ($H^+-ATPase$) inhibitor, bafilomycin (100 nM), reduced neurite extension indicating that ATP release resulted from $P2X_2$ receptor activation in PC12 cells is needed for neurite outgrowth. These were confirmed by activation of mitogen activated protein kinases, such as ERKs and p38. These results suggest roles of ATP and $P2X_2$ receptors in hormone-induced cell differentiation or neuronal synaptogenesis in local acidic environments.

• Korean Journal of Community Nutrition
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• v.21 no.3
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• pp.284-292
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• 2016

Objectives: This study compared the differences of postmenopausal women's bone mineral density in relation to the degree of obesity, metabolism index and dietary factors that affect bone mineral density. Methods: The subjects included in the study are 39 postmenopausal women of normal weight with body mass index less than $25kg/m^2$ and 32 postmenopausal who are obese. Anthropometry and biochemical analysis were performed and nutrient intakes and DQI-I were assessed. Results: Normal weight women were $56.03{\pm}3.76years$ old and obese women were $58.09{\pm}5.13years$ old and there was no significant difference in age between the two groups. The T-score of bone mineral density was $0.03{\pm}1.06$ in normal weight women and $-0.60{\pm}1.47$ in obese women and this was significantly different between the two groups (p<0.05). Blood Leptin concentration was significantly lower in normal weight women ($6.09{\pm}3.37ng/mL$) compared to obese women in ($9.01{\pm}4.99ng/mL$) (p<0.05). The total score of diet quality index-international was $70.41{\pm}9.34$ in normal weight women and $64.93{\pm}7.82$ in obese women (p<0.05). T-score of bone mineral density showed negative correlations with percentage of body fat (r = -0.233, p=0.05), BMI (r = -0.197, p=0.017), triglyceride (r = -0.281, p=0.020) and leptin (r = -0.308, p=0.011). The results of multiple regression analysis performed as the method of entry showed that with 22.0% of explanation power, percentage of body fat (${\beta}=-0.048$, p<0.05), triglyceride (${\beta}=-0.005$, p<0.05) and HDL-cholesterol (${\beta}=0.034$, p<0.01), moderation of DQI-I (${\beta}=-0.231$, p<0.05) affected T-score significantly. Conclusions: The results of the study showed that obese women have less bone density than those with normal weight women. In addition, the factor analysis result that affect bone mineral density showed that intake of fat is a very important factor. Therefore, postmenopausal women need to maintain normal weight and manage blood lipid levels within normal range. They also need to take various sources of protein and reduce consumption of empty calorie foods that have high calories, fat, cholesterol and sodium.

• Toxicological Research
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• v.34 no.3
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• pp.191-197
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• 2018

In 2015, a candidate for the second national reference standard (NRS) of Gloydius snake venom was produced to replace the first NRS of Gloydius snake venom. In the present study, the potencies of the candidate were determined by a collaborative study, and the qualification of the candidate was estimated. The potencies of the candidate were determined by measuring the murine lethal titers and lapine hemorrhagic titers of venom against the regional working reference standard (RWRS) for antivenom using the methods described in the previous report for the first NRS of Gloydius snake venom. Three Korean facilities contributed data from a total of 30 independent assays. Subsequently, two foreign national control research laboratories contributed to this collaborative study. The results were calculated using the Reed-Muench method for lethality and determined using a mixed-effects model for hemorrhage. The general common potencies of the lethal and hemorrhagic titers were obtained from the results of the 30 tests performed at three Korean facilities. The results are expressed in micrograms for 1 test dose (TD) with a 95% confidence interval as follows: a lethal titer of $90.13{\mu}g/TD$ (95% confidence interval = $87.39{\sim}92.86{\mu}g$) and a hemorrhagic titer of $10.80{\mu}g/TD$ (95% confidence interval = $10.46{\sim}11.14{\mu}g$). In addition, the candidate preparation showed good quality evaluation according to the results of the quality estimation of the candidate and is judged to be suitable to serve as the Korean NRS for snake venom. In conclusion, the second NRS of Gloydius snake venom was established in this study and will be used for national quality control, including a national lot release test of Korean antivenom products.

• Korean Journal of Poultry Science
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• v.13 no.2
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• pp.197-208
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• 1986

This experiment was conducted to find out the effects of the six different feeding methods on the development of body weight, testis, comb and pituitary gland, and the sexual maturity of White Plymouth Rock cockerels. From hatching to 22 weeks of age, the weights of whole body, testis, comb and pituitary gland, and the histological changes of testis and the semen characteristics were checked every other week. The results obtained in this expeniment were as follows: 1. The growth rates of the self-feeding groups were faster than those of the limited feeding groups (70 percent of the self-feeding) by about 2 weeks. The weights of testis and comb showed the most marked increase at 20 weeks of age in the self-feeding groups and at 22 weeks of age in the limited feeding groups, respectively. 2. The weights of pituitary gland from hatching to 22 weeks of age at all observation weeks were not recognised significantly among the compared groups except 4, 14 and 16 weeks of age. 3. Correlations between week of age, body weight, testis, comb and pituitary gland, in the course of 22 weeks, were highly significant. 4. The diameters of lumina and tubules in the seminiferous tubules increased very slowly until 10 weeks of age. They showed the most marked increase at 12 weeks of age in the self-feeding groups and at 14 weeks of age in the limited feeding groups, and then continuously increased until 32 weeks of. age. 5. Primary spermatocytes appeared at first at 8 weeks in the all treatment groups, Secondary spermatocytes appeared at first at 10 weeks in the self-feeding groups and at 12 weeks in the limited feeding groups. At 14 weeks of age spermatids and spermatozoa were found at first in the self-feeding groups but spermatids were found in the limited feeding groups. 6. Age of the first ejaculation was between 14 and 16 weeks of age in the all treatment groups. The Average semen. volume and sperm concentration ranged from 0.1-0.2$m\ell$/ ejaculate and 5.6-9.8${\times}$10$\^$8/ sperm/$m\ell$ at the age of the first ejaculation but 0.30-0.35$m\ell$/ ejaculate and 22.4-42.7${\times}$10$\^$8/ sperm int at the 20 weeks of age in the all treatment groups.

• Economic and Environmental Geology
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• v.30 no.3
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• pp.197-207
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• 1997

Rocks in the Cheongsong mine area consist of Precambrian gneiss, Cretaceous sedimentry rocks and late Cretaceous quartz porphyry. The Cheongsong deposit is composed of many hydrothermal quartz veins of strikes $N30^{\circ}{\sim}60^{\circ}W$, dips $60{\sim}85^{\circ}E$ which fill WNW fault system. Pyrite and hematite occur within transparent quartz near margins of early stage II, and milky quartz of middle stage II coexists with sphalerite, chalcopyrite and galena coexisting with Cu-Pb-Bi minerals in center part of stage II quartz veins. Stage III calcite vein filled cracks or fractures of earlier quartz veins contains native copper and chalcopyrite. Supergene minerals are chalcocite, covellite, malanchite and chrysocolla. Alteration minerals are sericite, chlorite, argillite, epitode and pyrite. Ranges of salinities and homogenization temperatures for fluid inclusions in the individual periods of stage II are: 3.7 to 7.8 wt.% eq. NaCl and 200 to $380^{\circ}C$ in transparent quartz of early stage II; 0.7 to 6.4 wt.% eq. NaCl and 200 to $320^{\circ}C$ in milky quartz of middle stage II; 0.0 to 0.9 wt.% eq. NaCl and 250 to $320^{\circ}C$ in calcite of late stage II. Those of stage III calcite range about 0 wt.% eq. NaCl, and from 140 to $260^{\circ}C$, respectively. The relationship between salinities and temperatures shows decrease tendency with paragenetic time from stage II to III. The ${\delta}^{18}O_{H_2O}$ value is 0.5‰ in stage I, range from 0.5 to -0.4‰ in stage II, and from -3.2 to -3.7‰ in stage III. Calcite in the stage II and stage III has ${\delta}^{13}C$ values of -5.0‰ and -4.5 to -4.9‰, respectively. There is a decrease in sulfur fugacity values with paragenetic time of stage II, from $10^{-6.3}$ atm for early mineralization, to $10^{-6.5}$ atm for middle stage, to $10^{-8.0}$ atm for late mineralization of stage II. The results of stable isotope and fluid inclusion indicate that ore fluids reacted with meteoric water and wall rock in the Cheongsong hydrothermal system.

• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.216-229
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• 2009

The flora of vascular plants in the Geumgang area (Mt. Guryongsan, Mt. Jeonwolsan, Mt. Samasan, Mt. Yongmeorisan and Mt. Hamrasan) was investigated to suggest strategies for conservation. This study was performed from May 2007 to April 2008, with total 17 times. The Korean endemic species, legally protected species and species to threaten domestic ecosystem species to threaten were grasped on this study. The flora consists of 334 taxa, 86 families 246 genera 297 species 34 varieies and 3 forms in total results from 5 sites in this study. Korean endemic species were confirmed 8 taxa. No rare and endangered species were found in this study. The 2 taxa of the fourth grade of specially designated plants announced the Ministry of Environment were investigated and 8 taxa of the third grade were confirmed. In totally, 24 taxa that are specially designated plants announced the Ministry of Environment including the first and the second grade taxa. 25 taxa of alien naturalized plants were confirmed. The degree of destroy of forest vegetation and reduction of plant diversity in the midstream of Geumgang were in proceeding by construction of multifunctional administrative city and cultivation. It is needed to set up strategies for conservation forest vegetation in this study area.

• Korean Journal of Agricultural Science
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• v.13 no.2
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• pp.193-197
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• 1986

This experiment was carried out to find out the effect of piglet anemia prevention of the chelated iron with amino acids fed to the sows during the late gestation and early lactation as compared with oral iron administration, intramuscular iron-dextran injection and control (receiving no iron supplement) groups. Twenty crossbred sows (Landrace ${\times}$ Large White) bred purebred Large White boars were used to evaluate four treatments. The results obtained in this experiment were as follows: 1. There were no significant differences among the average body weights at birth in all the treatment groups. But the average body weight at 15 days of age was heaviest in the chelated iron group. At 35 days of age, the control group was lightest in the treatment groups. 2. The survival rates at weaning were not recognized significantly among all the treatment groups. 3. At birth and 15 days of age, the levels of hemoglobin, red blood cell and hematocrit of the chelated iron group were higher (P<.05) than those of the control group. But at 35 days of age, they were not recognized significantly.

• Journal of Ginseng Research
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• v.40 no.3
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• pp.203-210
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• 2016

Background: Korean Red Ginseng (KRG) is a well-known natural product with anticarcinogenic and antioxidant effects. We evaluated the antifatigue effect of KRG in patients with nonalcoholic fatty liver disease (NAFLD). Methods: Eighty patients with NAFLD were prospectively randomized to receive 3 wk of KRG or placebo in addition to counseling on healthy eating and regular exercise. Liver function test, proinflammatory cytokines, adiponectin, antioxidant activity, and fatigue score were measured and compared according to the body mass index between the KRG and placebo groups. Results: The liver function tests were significantly improved after 3 wk of treatment in both groups. The mean levels (at baseline and after treatment) of tumor necrosis factor-${\alpha}$ were $108.0pg/mL{\pm}54.8pg/mL$ and $92.7pg/mL{\pm}39.0pg/mL$ (p = 0.018) in the KRG group and $123.1pg/mL{\pm}42.1pg/mL$ and $127.5pg/mL{\pm}62.2pg/mL$ (p = 0.694) in the placebo group, respectively. There was a significant difference in change of adiponectin levels between the KRG ($7,751.2pg/mL{\pm}3,108.1pg/mL$ and $8,197.3pg/mL{\pm}2,714.5pg/mL$) and placebo groups ($7,711.6pg/mL{\pm}3,041.3pg/mL$ and $7,286.1pg/mL{\pm}5,188.7pg/mL$, p = 0.027). In patients with overweight, the fatigue score was significantly decreased in the KRG group ($35.0{\pm}13.2$ and $24.5{\pm}8.9$, p = 0.019). Conclusion: Our results show that KRG might be effective in reducing proinflammatory cytokine and fatigue in overweight patients with NAFLD, in addition to improvements in adiponectin levels.