• Title/Summary/Keyword: $MgO_24$

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Surface characteristics and bioactivity of minocycline-treated Ti-6Al-4V alloy

  • Lee, Jung-Hyuk;Sun, Young-Gon;Na, Eui-Ri;Moon, Jong-Wook;Kim, Young-Joon
    • Oral Biology Research
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    • v.42 no.4
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    • pp.187-197
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    • 2018
  • Chemical agents such as minocycline (MC) and citric acid (CA) were suggested in the treatment of contaminated implant surface. In this study, MC-HCl treatment was performed to enhance surface characteristics of titanium alloy surface. The purpose of this study was to assess the characteristics and the biocompatibility of Ti-6Al-4V surface treated by MC. Alpha-beta titanium alloy (Ti-6Al-4V) samples were prepared and they were divided into 6 groups according to chemical concentration and treatment time. These groups include 1) group I, non-treated smooth titanium alloy; 2) group II, MC 1.5 mg/mL for 1 hour; 3) group III, MC 1.5 mg/mL for 24 hours; 4) group IV, MC 15 mg/mL for 10 minutes; 5) group V, MC 100 mg/mL for 5 minutes; 6) group VI, pH1 CA for 3 minutes. The analysis of the surface characteristics of MC-treated titanium alloy was executed using scanning electron microscopy, roughness test, and X-ray photoelectron spectroscopy (XPS). Cell adhesion and MTT assay was done using MC3T3 cell. Titanium surfaces treated with MC indicated a more smoothened surface microstructure. For group II and III, the new peaks of rutile TiO2 were found. Group II and V have more basic group of Ti-OH form in XPS. In MTT assay, all MC-treated groups showed significantly higher cell viability compared to control. The surface roughness, crystal structure, surface hydrophilicity, cell viability of smooth titanium surface was improved by MC treatment. Compared with the control experiment and CA-treated group, smooth titanium surface treated with MC showed improved surface characteristics and cell biocompatibility.

The Antioxidant Activities and Neuroprotective Effects of Hot Water Extracts from Torreyae Semen (비자 열수 추출물의 항산화 활성 및 뇌신경세포 보호효과 연구)

  • Lee, Soong-In;Choi, Chan-Hun;Kim, Jeong-Sang;Lim, Seong-Soo;Jung, Hyun-Woo
    • The Korea Journal of Herbology
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    • v.32 no.6
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    • pp.41-48
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    • 2017
  • Objectives : This study was designed to estimate the antioxidative and neuroprotective effects of Torreyae Semen hot water extracts (TS). Methods : Torreyae Semen was extracted by hot water for 2 hours with a temperature of 105 degrees. Polyphenols and total flavonoid were measured and LC-MS/MS was used to certificate anticipated antioxidative compounds. The antioxidant activities of TS were measured as scavenging effects of 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and Nitrite Oxides (NO). Cell viability and proliferation rate was measured MTT assay. The toxicities to thymocytes and splenocytes were evaluated by the proliferation rate of primary cultured cells of 7 weeks, male Balb/c mice. The antioxidant activities of TS on C6 mouse glioma cells were measured by the analysis of total glutathione contents variation. The neuroprotective effects against oxidative stresses were measured by MTT assay. Results : Polyphenols of TS was $92.00{\pm}1.24{\mu}g/mg$, and total flavonoids was $0.36{\pm}0.14{\mu}g/mg$. TS includes gallocatechin, epigallocatechin, gallocatechin gallate and epigallocatechin gallate. TS included gallocatechin, epigallocatechin, gallocatechin gallate, epigallocatechin gallate. TS showed DPPH and NO scavenging effects as dose-dependent manner at the concentrations of $0-10mg/m{\ell}$. In MTT assay, TS shows no significant toxicity to C6 cells, primary cultured thymocytes and splenocytes of Balb/c mice. TS increased the level of total glutathiones. TS increased cell viabilities of C6 cells against oxidative stresses such as $H_2O_2$, sodium nitroprusside (SNP), Rotenone at the concentrations of $0-0.063mg/m{\ell}$. Conclusions : TS shows the antioxidant and neuroprotecitive effects in these experiments.

Antimicrobial Activities and Adherence Inhibition on Streptococcus mutans by Ethyl Acetate Extract from Caesalpinia sappan L. (소목(Caesalpinia sappan L.)의 에틸아세테이트 분획물이 Streptococcus mutans에 대한 항균활성 및 부착 억제)

  • Kwon, Hyun-Jung;Kim, Yong-Hyun;Han, Kook-Il;Jeon, Mi-Ae;Han, Man-Deuk
    • Journal of dental hygiene science
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    • v.12 no.2
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    • pp.155-162
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    • 2012
  • Somok, the heart wood of Caesalpinia sappan is used in traditional Chinese medicine. Adherence of S. mutans to the tooth surface can result in the formation of a dental plaque. This study was performed to investigate the antibacterial activity and bacterial adhesion of ethyl acetate extract from C. sappan against S. mutans ATCC 25175. The bacteria were cultured in brain heart infusion(BHI) broth, and then incubated under 5% $CO_2$ at $37^{\circ}C$ for 18~24 hours. The antimicrobial activity of the ethyl acetate extract of C. sappan was then examined using the paper disc methods and MIC. In addition, bacterial adherence to hydroxyapatite was also examined. The ethyl acetate extract was shown to produce inhibitory effects and had MIC values of 125 mg/ml against S. mutans ATCC 25175. The ethyl acetate extract inhibited adhesion of S. mutans to saliva coated-hydroxyapatite beads(S-HA). At 24 hr, the ethyl acetate extract significantly reduced the adherence of S. mutans to S-HA beads relative to the control. The isolated active substance was identified as brazilin($C_{16}H_{14}O_5$) by $^1H-NMR$ and $^{13}C-NMR$. Thus, the application of C. sappan can be considered a useful and practical method for the prevention of dental caries.

Studies on the Main Factors Affecting the Mycelial Growth of Phellinus linteus (목질진흙버섯균 Phellinus linteus의 균사체 생육에 미치는 주요 인자에 관한 연구)

  • Chi, Jeong-Hyun;Ha, Tae-Moon;Kim, Young-Ho;Rho, Yeong-Dock
    • The Korean Journal of Mycology
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    • v.24 no.3 s.78
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    • pp.214-222
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    • 1996
  • This study was carried out to obtain the basic data on artificial culture of Phellinus linteus. The optimum condition for the mycelial growth was $25{\sim}30^{\circ}C$ and pH $6.0{\sim}7.0$. The carbon sources such as D-glucose, D-mannose and Dextrose were favorable to mycelial growth. As nitrogen sources, peptone, cassamino acid and glutamic acid appeared to be favorable. The optimum C/N ratio was about 20:1, when 2% of glucose was provided as a carbon source. The better organic acids and vitamin among tested ones were gallic, silicic acids and biotin. The mineral nutrients of $KH_2PO_4,\;FeSO_4{\cdot}7H_2O,\; MgSO_4{\cdot}7H_2O,\;ZnSO_4{\cdot}7H_2O$ were effective and the optimum concentrations were 0.05, 0.001, 0.02 and 0.003%, respectively.

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FT-transgenic spray-type Chrysanthemum (Dendranthema grandiflorum Kitamura) showing early-flowering (FT 유전자 형질전환 스프레이 국화 (Dendranthema grandiflorum (Ramat.) Kitamura)의 조기개화성)

  • Lee, Su-Young;Han, Bong-Hee;Hur, Eun-Joo;Shin, Hak-Kee;Lee, Il-Ha;Lee, Eun-Kyung;Kim, Seung-Tae;Kim, Won-Hee;Kwon, O-Hyeon
    • Journal of Plant Biotechnology
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    • v.39 no.3
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    • pp.140-145
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    • 2012
  • The flowering locus T (FT) gene, of which expression will be controlled at high temperature by heat shock promoter (it printed as to HSproFT), was introduced into spray-type chrysanthemum (Dendranthema grandiflorum (Ramat.) Kitamura) 2 cultivars ('Pink PangPang' and 'Pink Pride' by co-cultivation with Agrobacterium tumefaciens strain C58C1 harboring pCAMBIA2300 containing the HSproFT gene. After leaf segments of the 2 cultivars were infected with the A. tumafaciens with C58C1 as explants, shoots were regenerated from the explants cultured on the $1^{st}$ selection medium (MS basal salts + 1.0 mg/L BA, 0.5 mg/L IAA + 10 mg/L kanamycin + 0.7% plant agar, pH 5.8). The shoots were transferred into the $2^{nd}$ selection medium (MS basal salts + 1.0 mg/L BA, 0.5 mg/L IAA + 20 mg/L kanamycin + 0.7% plant agar, pH 5.8). One hundred seventeen plantlets from 'Pink PangPang' and 5 ones from 'Pink Pride' were confirmed as transformants by PCR analysis. Twenty six of the transformants and non-transformants were acclimatized and established well in a green house. Eights of 26 transgenic lines showed flower bud 1.7~10 days earlier than nontransgenic plants, and 24 of them flowered 1~6 days earlier than non- transgenic plants. The shape and color of flower of all HSproFT-transgenic lines were not different with those of non- transgenic plants.

Effects of Calcium Fertilization on Oxalate of Napiergrass and on Mineral Concentrations in Blood of Sheep

  • Rahman, M.M.;Nakagawa, T.;Niimi, M.;Fukuyama, K.;Kawamura, O.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.12
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    • pp.1706-1710
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    • 2011
  • An experiment was conducted to investigate the effects of calcium (Ca) fertilization on oxalate content in napiergrass (Pennisetum purpureum) and on some blood parameters of sheep. Re-growth napiergrass was grown with or without Ca fertilizer and offered to sheep. Eight sheep, divided into two groups of 4 animals each were used. Calcium-fertilized napiergrass was offered daily to the animals as experimental treatment, whereas without Ca-fertilized napiergrass was given to the animals as control. Results showed that there was a trend to lower soluble and total oxalate concentrations in Ca-fertilized grass than control. The Ca-fertilized grass contained (p<0.05) lower concentrations of K and Mg than control, though Ca fertilization had no affect (p>0.05) on Ca and Na concentrations in plants. Feeding of Ca-fertilized grass had no affect on the feed consumption, blood Mg level and daily gain of sheep. However, sheep fed control grass had lower (p<0.05) blood Ca level than sheep fed Ca-fertilized grass. Our findings suggest that Ca fertilization might minimize the negative effects of oxalate.

Studies on the Preparation of $^{99m}TC$ Labelled Human Albumin Microsphere for Lung Scintigraphy (폐 신티그래피용 $^{99m}TC$ 표지 미소구형인 혈청 알부민의 제조에 관한 연구)

  • Park, Kyung-Bae;Awh, Ok-Doo;Kim, Jae-Rok
    • The Korean Journal of Nuclear Medicine
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    • v.23 no.1
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    • pp.63-69
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    • 1989
  • In order to develop technetium-99m-labelled human albumin microsphere (HAM) for lung scintigraphy, various experimemts such as preparation and fractionation of HAM, establishment of optimal labelling conditions, determination of radiochemical purity, stability test and biodistribution of $^{99m}Tc-HAM$ were carried out. HAM was prepared from the suspension of 1ml aqueous human serum albumin (25%) in 130 ml of olive oil at $130\sim135^{\circ}$ with vigorous stirring. The resulting HAM was fractionated with microsieve to get the desired particle size $(15\sim50\mu)$ and autoclaved for sterilizaiton. The HAM particles were treated with stannous chloride and the pH of the suspension was adjusted to $3.0\sim3.5$ with phosphate buffer. After freeze-drying the contents of single reaction vial containing 5 mg of HAM and 0.2 mg of $SnCl_2$ it was reacted with $Na^{99m}TcO_4$. The labelling yield was higher than 99.5% and the stability of $^{99m}Tc-HAM$ was high enough to maintain 99.1% of radiochemical purity up to 24 hours. Lung and liver uptake in mice was found to be 94% and 0.9%, respectively. Excellent rabbit and human lung scans were also obtained.

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Analysis of discharge characteristic by variations of discharge time and ambient temperature in AC-PDP (방전 시간과 주위 온도변화에 따른 AC-PDP의 방전 특성 변화 분석)

  • Sim, Choung-Hwan;Kim, Hyun-Gyu;Kim, Yun-Gi;Cho, Sung-Yong;Park, Cha-Soo;Kim, Dong-Hyun;Lee, Hae-June;Lee, Ho-Jun;Park, Chung-Hoo
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1429_1430
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    • 2009
  • 본 연구에서는 7인치 샘플패널의 가속 Aging 실험을 통해 Aging time(24hr~529hr)변화에 따른 오방전 발생 Mechanism을 분석하고자 했다. 상온에서 Aging time변화에 따른 정마진, 휘도, Vt close curve를 측정 하였고 시간과 온도(고온: $70^{\circ}C$, 상온: $25^{\circ}C$, 저온: $-20^{\circ}C$)에 따른 Discharge time lag의 변화양상을 측정하였다. 그리고 Sustain pulse수의 조절을 통해 패널의 Priming 조건을 제어하면서 오방전 발생 확률을 수치적으로 측정하였다. 실험을 통해, 패널의 Aging time이 늘어남에 따라서 상판의 MgO층에서 Sputtering현상이 발생하여 MgO 잔재들이 하판의 형광체 표면을 덮는 등 방전 개시 전압의 변화가 오방전 발생에 주요한 원인임을 알 수 있었다.

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Hypoglycemic and antihyperglycemic activity of leaf extract of pluchea indica Less

  • Pramanik Kartick Chandra;Bhattacharya Plaban;Biswas Ria;Bandyopadhyay Durba;Mishra Moumita;Chatterjee TK
    • Advances in Traditional Medicine
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    • v.6 no.3
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    • pp.232-236
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    • 2006
  • The hypoglycemic and antihyperglycemic activity of methanolic extract of Pluchea indica Less. (Asteraceae) (MEPI) leaves were studied in normal rats and in streptozotocin induced diabetic rats respectively. The blood glucose levels were measured at 1, 4, 8, 16 and 24 h intervals after the treatment. The MEPI leaves showed reduction in blood glucose level in normal (35.12% and 36.01 % for 200 and 400 mg/kg, p.o. respectively) and in steptozotocin induced diabetic rats (36.10% and 41.87% for 200 and 400 mg/kg respectively). A toxicity study has been performed for the extract, which revealed that the extract is safe to use even at the doses of 3.2 gm/kg of body weight orally.

Antioxidant and Antibacterial Properties of Hovenia (Hovenia dulcis) Monofloral Honey Produced in South Korea

  • Park, Seung Hee;Kim, Young Ki;Kim, Moon Seob;Lee, Seung Ho
    • Food Science of Animal Resources
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    • v.40 no.2
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    • pp.221-230
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    • 2020
  • The aim of this study was to evaluate the antioxidant and antibacterial activity of Hovenia (Hovenia dulcis) monofloral honey produced in Korea. To produce Hovenia monofloral honey, Hovenia trees were surrounded by a net house, and honeybees were breed there over a 20-day period. Hovenia monofloral honey contained more than 95% of Hovenia pollen and showed physicochemical properties in agreement with the international honey standard (Codex). The total phenolic and flavonoid contents of Hovenia monofloral honey ranged from a 24.82-27.00 mg gallic acid equivalent/100 g honey and a 0.41-0.46 mg quercetin equivalent/100 g honey, respectively. In addition, to evaluate the functional properties of Hovenia monofloral honey, the antioxidant activity of Hovenia monofloral honey was estimated by using the 1,1-diphenyl-2-picrylhydrazyl radical and the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assay. Furthermore, Hovenia monofloral honey showed an antibacterial activity against foodborne gram positive (Listeria monocytogenes and Staphylococcus aureus) and gram negative bacteria (Salmonella Typhimurium and Escherichia coli O157:H7).