• Title/Summary/Keyword: rate dependent

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Effects of irradiation on the calcific nodule formation in MC3T3-El osteoblastic cell line (MC3T3-El 골모세포주의 석회화결절 형성에 방사선이 미치는 영향)

  • Kang Ki-Hyun;Lee Sang-Rae;Kwon Ki-Jeong;Koh Kwang-Joon
    • Imaging Science in Dentistry
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    • v.35 no.1
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    • pp.1-8
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    • 2005
  • Purpose : To investigate the effects of irradiation on the calcium content and calcific nodule formation in the MC3T3-E1 osteoblastic cell line. Materials and Methods : Cells were irradiated with a single dose of 2,4 and 8 Gy at a dose rate of 5.38 Gy/min using a Cs-137 irradiator. After irradiation, the calcium content and calcific nodule formation were examined on the 1 st, 2nd, 3rd and 4th week. Results : A decreasing dose-dependent tendency of the cell proliferation rate was found in all irradiated groups of this experiment when compared with the unirradiated control group. In accordance with the duration of culture, there was no significant difference in the cell proliferation rate after irradiation of 2 Gy when compared with the unirradiated group, however a decreasing tendency was found in 4 Gy- and 8 Gy-irradiated groups. While an increase in total calcium content after irradiation of 2 Gy was found at week 1, week 2, and week 4, there was a decrease in calcium content at week 1 through 4 in the 8 Gy- irradiated group. Calcific nodule formation was increased in irradiated experimental groups when compared with the unirradiated control group in the 2 Gy-irradiated group, but decreased in the 4 Gy- and 8 Gy-irradiated groups at the same stage. Conclusion : The results showed a mild increasing tendency of the calcific nodule formation after irradiation of 2 Gy. However, a decreased calcific nodule formation in 4 Gy- and 8 Gy-irradiated groups was found. Taken together, the irradiation of 2 Gy mildly activated bone formation, however 4 Gy or 8 Gy suppressed bone formation by decreasing cell numbers in the MC3T3-El osteoblastic cell line.

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Effects of Chlorhexidine digluconate on Rotational Rate of n-(9-Anthroyloxy)stearic acid in Model Membranes of Total Lipids Extracted from Porphyromonas gingivalis Outer Membranes

  • Jang, Hye-Ock;Kim, Dong-Won;Kim, Byeong-Ill;Sim, Hong-Gu;Lee, Young-Ho;Lee, Jong-Hwa;Bae, Jung-Ha;Bae, Moon-Kyoung;Kwon, Tae-Hyuk;Yun, Il
    • The Korean Journal of Physiology and Pharmacology
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    • v.8 no.2
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    • pp.83-88
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    • 2004
  • The purpose of this study was to provide a basis for studying the molecular mechanism of pharmacological action of chlorhexidine digluconate. Large unilamellar vesicles (OPGTL) were prepared with total lipids extracted from cultured Porphyromonas gingivalis outer membranes (OPG). The anthroyloxy probes were located at a graded series of depths inside a membrane, depending on its substitution position (n) in the aliphatic chain. Fluorescence polarization of n-(9-anthroyloxy)stearic acid was used to examine effects of chlorhexidine digluconate on differential rotational mobility, while changing the probes' substitution position (n) in the membrane phospholipids aliphatic chain. Magnitude of the rotational mobility of the intact six membrane components differed depending on the substitution position in the descending order of 16-(9-anthroyloxy)palmitic acid (16-AP), 12, 9, 6, 3 and 2-(9-anthroyloxy)stearic acid (12-AS, 9-AS, 6-AS, 3-AS and 2-AS). Chlorhexidine digluconate increased in a dose-dependent manner the rate of rotational mobility of hydrocarbon interior of the OPGTL prepared with total lipids extracted from cultured OPG, but decreased the mobility of membrane interface of the OPGTL. Disordering or ordering effects of chlorhexidine digluconate on membrane lipids may be responsible for some, but not all of its bacteriostatic and bactericidal actions.

The Comparative Study on the Effect of Constitution-dependent Acupuncture Treatment for Idiopathic Parkinson's Disease on Heart Rate Variability (체질에 따른 침치료가 특발성 파킨슨 환자의 심박변이도에 미치는 영향)

  • Kim, Haeng-Beom;Lee, Min-Ho;Lee, Soh-Young;Nam, Dong-Woo;Yang, Dong-Hoon;Choi, Yang-Sik;Park, Yeon-Chul;Koh, Hyung-Kyun;Lee, Yun-Ho
    • Journal of Acupuncture Research
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    • v.24 no.3
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    • pp.163-174
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    • 2007
  • Objectives : This study was designed to evaluate the effect of acupuncture on Heart Rate Variability(HRV) of patients with Parkinson's disease. Methods: Subjects were voluntarily recruited through newspaper and internet advertisement. All the subjects were confirmed as idiopathic Parkinson's disease by a neurologist. Patients were divided into three groups. Experimental group was acupunctured based on Sasang Constitution. Standard group was acupunctured on $LR_3$, $GB_{34}$ and $ST_{36}$. Control group was sham-acupunctured. Acupuncture was applied 2 times a week for four weeks by an oriental medical doctor at Kyung-hee Oriental Medical Hospital. The patients were assessed by HRV before and 4 weeks after the treatment. Results : The results were as follows 1. In experimental group, increase in SDNN, TP, LF, HF Nonn were statistically significant after 4 weeks compared to the pre-treatment. 2. In standard group, increase in SDNN, TP, LF were statistically significant after 4 weeks compared to the pre-treatment. 3. After 4 weeks of treatment SDNN, LF showed statistically significant cufferences among three groups. Conclusions : This study suggests that acupuncture treatment based on Sasang Constitution and other specific acupuncture treatment can be beneficial for patients with idiopathic Parkinson's disease. Further study on various acupuncture treatment for Parkinson's disease is required.

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Isolation of Cryptosporidium parvum oocysts from fecal samples - The combination of ether extraction and discontinuous sucrose gradients (분변에 함유된 Cryptosporidium parvum 오오시스트의 순수분리 -Ether extraction과 discontinuous sucrose gradients의 병용)

  • 위성환;이정길
    • Parasites, Hosts and Diseases
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    • v.32 no.1
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    • pp.7-12
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    • 1994
  • A calf and 50 mice were infected with Cryptosporidium parvum and their fecal materials were collected and treated 10 ether extraction (EE), followed by discontinuous sucrose gradients (DSG) method. EE method was to remove some of fat or lipid from feces. Sediments were washed by centrifugation ($1,500{\;}{\times}{\;}g$ for 10 min., 3 times) In phosphate-buffered saline and then these washed sediments were sleeved sequentially through stainless steel screens with a final mesh of 250 ($61{\;}{\mu\textrm{m}}$ porosity) to remove other debris. After sieving, the materials were suspended in 2.5% potassium dlchromate solution. Oocysts were counted by using a hemocytometer and the recovery rate of pure oocysts was calculated on the basis of the count. Following centrifugation ($1,500{\;}{\times}{\;}g$ for 30 min.) by DSG method, most oocysts were recovered at the interface between a gravity of 1.103 and 1.064. The recovery rates of pure oocysts from the fecal suspension of the calf ($3.8{\;}{\times}{\;}10^7/ml$) and the mouse ($3.2{\;}{\times}{\;}10^6/ml$) treated with EE method were 81.6% and 51.6%, respectively. It is suggested that the recovery rate was dependent on the number of oocysts In each suspension treated with EE method. To get the 50% recovery rate, there must be more than $2{\;}{\times}{\;}10^6$ oocysts per ml of the fecal suspension treated with EE method. By the combination of the two methods it was possible to isolate C. parvum oocysts from normal feces of the calf and mouse as well as from dlarrhelc feces.

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Persistent endemicity of Gymnophalloides seoi infection in a southwestern coastal village of Korea with special reference to its egg laying capacity in the human host

  • Chai, Jong-Yil;Lee, Geun-Chan;Park, Yun-Kyu;Han, Eun-Taek;Seo, Min;Kim, Jin;Guk, Sang-Mee;Shin, Eun-Hee;Choi, Min-Ho;Lee, Soon-Hyung
    • Parasites, Hosts and Diseases
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    • v.38 no.2
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    • pp.51-57
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    • 2000
  • Follow-up studies have been conducted every three years on the endemicity of Gymnophalloides seoi infection in a small coastal village of Chollanam-do (Province), Korea, since it was first known as an endemic area in 1994. Special attention was given to its egg laying capacity in the human host. In fecal examinations, the overall helminth egg and/or cyst positive rate was 78.7% (74/94) in 1997 and 76.6% (82/107) in 2000. Among them G. seoi eggs showed the highest rate; 71.3% (67/94) in 1997 and 72.0% (77/107) in 2000. The average number of eggs per gram of feces (EPG) was 1,015 in 1997, while a reduced rate of 353 was observed in 2000. In 1997, total of 320,677 adult flukes of G. seoi (av. 10,344/person, 94-69,125 in range) were collected from the diarrheic stools of 31 treated patients. The EPG/worm obtained from 21 cases ranged from 0.04 to 0.77 (av. 0.23), suggesting density-dependent constraints on the worm fecundity. The relationship between the worm burden (X) and EPG/worm (Y) can be expressed as $Y=0.42{\cdot}e{\cdot}^{-l.2x}(r=0.49)$. The results showed that G. seoi infection is persistently endemic in this village.

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Development of the Standard Blood Inventory Level Decision Rule in Hospitals (병원의 표준 혈액재고량 산출식 개발)

  • Kim, Byoung-Yik
    • Journal of Preventive Medicine and Public Health
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    • v.21 no.1 s.23
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    • pp.195-206
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    • 1988
  • Two major issues of the blood bank management are quality assurance and inventory control. Recently, in Korea blood donation has gained popularity increasingly to allow considerable improvement of the quality assurance with respect to blood collection, transportation, storage, component preparation skills and hematological tests. Nevertheless the inventory control, the other issue of blood bank management, has been neglected so far. For the supply of blood by donation barely meets the demand, the blood bank policy on the inventory control has been 'the more the better.' The shortage itself by no means unnecessitate inventory control. In fact, in spite of shortage, no small amount of blood is outdated. The efficient blood inventory control makes it possible to economize the blood usage in the practice of state-of-the-art medical care. For the efficient blood inventory control in Korean hospitals, this tudy is to develop formulae forecasting the standard blood inventory level and suggest a set of policies improving the blood inventory control. For this study informations of $A^+$ whole bloods and packed cells inventory control were collected from a University Hospital and the Central Blood Bank of the Korean Red Cross. Using this informations, 1,461 daily blood inventory records were formulated.48 varieties of blood inventory control environment were identified on the basis of selected combinations of 4 inventory control variables-crossmatch, transfusion, inhospital donation and age of bloods from external supply. In order to decide the optimal blood inventory level for each environment, simulation models were designed to calculate the measures of performance of each environment. After the decision of 48 optimal blood inventory levels, stepwise multiple regression analysis was started where the independent variables were 4 inventory control variables and the dependent variable was optimal inventory level of each environment. Finally the standard blood inventory level decision rule was developed using the backward elimination procedure to select the best regression equation. And the effective alternatives of the issuing policy and crossmatch release period were suggested according to the measures of performance under the condition of the standard blood inventory level. The results of this study' were as follows ; 1. The formulae to calculate the standard blood inventory level($S^*$)was $S^*=2.8617X(d)^{0.9342}$ where d is the mean daily crossmatch(demand) for a blood type. 2. The measures of performace - outdate rate, average period of storage, mean age of transfused bloods, and mean daily available inventory level - were improved after maintenance of the standard inventory level in comparison with the present system. 3. Issuing policy of First In-First Out(FIFO) decreased the outdate rate, while Last In-First Out(LIFO) decreased the mean age of transfused bloods. The decrease of the crossmatch release period reduced the outdate rate and the mean age of transfused bloods.

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Electron Microscopical Observation of Transglutaminase-treated Ultra High Temperature Milk Sedimiment (Transglutaminase로 처리한 초고온 살균유 침전물의 전자현미경적 관찰)

  • Moon, Jeong-Han;Hong, Youn-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.8
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    • pp.1359-1366
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    • 2004
  • Ultra high temperature treated (UHT) skim milk and colloidal calcium phosphate-free skim milk were treated with microbial transglutaminase (TGase), ultracentrifuged at various rates, lyophilized, and observed for morphological properties with a scanning electron microscope (SEM). UHT skim milk showed small holes of associated micelles at lower centrifugal rates, and became thick and irregular, and fine particles were associated regularly at higher centrifugal rates. When UHT skim milk with TGase was incubated for 1 hour, casein micelles aggregated and broadened as centrifugation rate increased. When UHT skim milk with TGase was incubated for 8 hours, casein micelles were associated irregularly to large aggregates and widened. Colloidal calcium phosphate-free skim milk with TGase incubated for 1 hour and separated by two-step centrifugation showed aggregated lump, while the milk incubated for 8 hours with TGase was associated with broadened, compact, and regular layers as the centrifugation rate increased. Such phenomena were caused by heat treatment, protein crosslinking reaction catalyzed by TGase and conformational changes of casein molecules, and could be dependent on reaction time, temperature and ultracentrifugation rate.

Inductive Effects of Ginseng Saponins on the Rat LDH A-gene and the Synthetic rate of Hepatocyte DNA in Regenerating Rat Liver Cells (인삼사포닌의 흰쥐 LDH-A 유전자와 흰쥐 간세포 재생시 DNA 합성률에 미치는 유도효과)

  • 유계진;이광율;이성기
    • Journal of Ginseng Research
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    • v.14 no.2
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    • pp.200-206
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    • 1990
  • The effects of ginseng saponins, SRbl and G-Rc on the rat liver LDH A-gene transcriptional activity was investigated during prereplicative phase of rat liver after partial hepatectomy. Changes in LDH A-mRNA levels in regenerating rat liver after intraperitoneal administrations of G-Rbl or 'G-Rc were tested by slot blot hybridization methods. The results showed that G-Rbl (1 mg/100g B.W) and G-Rc (1 mg/100g B.W) caused marked increases of LDH A-mRNA contents by respectively 1.9- and 1.5-fold in rat liver at 5-hours after partial hepatectomy Dose dependent elect of G-Rbl and G-Rc (1-25 mg/ 100g B.W) on the LDH A-mRNA levels on regenerating rat liver were also analyzed. The maximal increases of liver LDH A-mRNA levels were observed with the doses of 1 mg for G-Rbl and 5 mg for G-Rc. However, when the administration doses of G-Rbl and G-Rc were increased to 20 mg, G-Rbl caused a marked decrease of LDH A-mRNA level to 61% of those in sham-operated rat liver. In contrast, G-Rc slightly decreased the liver LDH A-mRNA contents by 30% as compared to those of the maximum value but still maintained 22% higher LDH A-mRNA levels then those of sham-operated rate liver. On the basis of these experimental results, we conclude that ginseng saponin, G-Rbl and G-Rc have stimulatory effect at the lower concentration (1 mg/ 100g B.W) and inhibitory effect at the higher concentration (20 mg/ 100g B.W) on the LDH A-gene transcription during regeneration of rat liver. Additionally we also investigated the stimulatory effects of ginsenosides on the protein and DNA sinthetic activities in hepatocyte primary cell cultures isolated from regenerating rat liver. Both of G-Rc and -Re increased the synthetic rates of hepatocytes proteins and DNA at the administration doses of 50 us and 100 $\mu\textrm{g}$/3 ml/dish respectively representing 1.3-1.6 fold increases. From these results we postulate that G-Rc and -Re may have a mitogen ehincer activity for the hepatocyte proliferation during rat liver regeneration period.

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Automation of Longline -Magnetic Splitting Machine for Hooks- I- (주낙 어구의 자동화 -전자식 낚시 분리장치에 관한 연구- I-)

  • LEE Chun-Woo;KO Kwan-Soh
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.2
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    • pp.93-99
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    • 1986
  • A longline is made of many snoods with baited hooks which are connected to mainline at constant intervals. Hauling the mainline, removing the unused baits and the hooked fish, and the arrangement of hooks are dependent on mainly manual labour as compared with mechanized other fishing gear in fishing operation. The mechanization for longline operation is needed in order to eliminate the manual handling and to shorten the labour time. The magnetic hook splitting apparatus which consists of the hook separator and the guide leading to storage magazine rail was devised for the mechanization of hauling operation. The experiments were carried out in order to measure the splitting rate of hooks in accordance with the hauling speed of mainline and magnetic flux density of splitting apparatus from February to November, 1985. The splitting rate was $94\%$ for the Alaska pollack (Theragra chalcogramma) hook and $96\%$ for the halibut (Paralichthys olivaceus) hook at the hauling speed 24 m/min and magnetic flux density 482 gauss. The unsplitting of hooks was caused by entangling snood in the mainline and low magnetic flux density. The rate is greater the faster hauling speed and the lower magnetic flux density, with an average of about $6\%$, The magnetic flux density needed to hook splitting becomes increased with the increasing hauling speed. When the practical hauling speed is from 20 to 35m/min, the magnetic flux density is needed from 400 to 850 gauss.

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Mutagenic Mechanism of Chloropropanols in Escherichia coli (대장균 변이주를 이용한 Chloropropanol 변이원성 기구의 해석)

  • Song, Geun-Seoup;Han, Sang-Bae;Choi, Dong-Seong
    • Korean Journal of Food Science and Technology
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    • v.31 no.1
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    • pp.246-251
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    • 1999
  • This study was designed to evaluate the mutagenicity and the primary mutagenic mechanism of chloropropanols by using various genotypes of E. coli WP2, E. coli TK and E. coli GW series strains. Chloropropanols showed the low mutagenic activities in E. coli WP2s and WP2 establishing the following order; 2,3-DCP> 3-MCPD>1,3-DCP. As compared with E. coli WP2s, the decrease of mutagenic activity and the increase of survival rate in E. coli WP2 $(WP2s\;uvrA^+)$ suggest that DNA lesions produced by chloropropanols could be easily removed by excision-repair system. From the diminution of mutagenic activity and survival rate in E. coli CM611 (WP2s lexA), it was confirmed that the mutagenesis by chloropropanols was dependent on the SOS-repair system. This fact could be also confirmed from the result that both the mutagenic activity and survival rate in E. coli TK610 (umuC) were much lower than those in E. coli TK603 $(umuC^+)$. In the experiment to examine the possibility that chloropropanols might have effects on the LexA of SOS response negative regulator, there was no variation in ${\beta}-galactosidase$ activities of E. coli GW1105 $[lexA3\;(Ind^-)]$ and GW1107 [lexA51 (Def)] by addition of the compounds, indicating that chloropropanols do not have any effects on the LexA, itself.

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