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A Study on Satisfaction of Practicing Dentists about Prosthesis in Pusan Part I : About Fixed Prosthetic appliances (부산지역(釜山地域) 개업치과(開業齒科)의 치과보철물(齒科補綴物)에 관(關)한 만족도(滿足度) 조사(調査)(I) - 일부정식 치과 보철물에 관하여 -)

  • Lee, Myung-Kon
    • Journal of Technologic Dentistry
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    • v.10 no.1
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    • pp.159-169
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    • 1988
  • Fixed prosthetic appliance is the restorations of damaged teeth with cast metal or porcelain, and of replacing missing teeth with fixed, or cemented prosthesis. Successfully treating a patient by means of fixed prosthodontics requires the thoughtful combination of dentist and dental laboratory technician. In order to know the satisfaction of dentisits about fixed prosthetic appliances-porcelain, precious and non precious metal-, this study was conducted for 69 practicing dentisis in Pusan during Fed. to Mar. 1988 using a questionnaire method and was analyzed by the use of percentage, $X^2$-test The results are obtained as follow: 1. General characteristics of the respondents, The rate of age distribution of practcing dentists responded was as follow : 31$\sim$35 age group is 29.0%, 51$\sim$55age group 18.8%, 41$\sim$45 age group and 46$\sim$50 group each 11.6%, 36$\sim$40 age group and 56$\sim$60 age group 8.7%, over 60 age group 7.3%, below 30 age group 4.3% respectively. The tate of term of practice experience distribution of dentists responded was as follow : 6$\sim$10 year group 26.1%, 25$\sim$25year group 18.8%, 11$\sim$15 years group and 16~20 years group each 13.0%, below 5 years group and over 30 years group each 10.2%, 26$\sim$30 years group 8.7% in order. The rate of respondents’ degree was follow : bachelor group 81.2%, doctor group 13.0%, master group 5.8% in order. The rate of respondents’completed medical specialist course was as follow : non-complete group 75.4%, complete group 24.6%. The rate of having own laboratory in respondents’clinic was as follow : no having own laboratory group 58.0%, having own labiratory group 42.0% The rate of being lab. technician in respondent;s clinic was as follow: non-being lab. technician group 91.3%, being lab. technician group 8.7%. The rate of transactional commercial dental lab. numbers was as follow : I dental lab. group 40.6%, 2 dental lab. group 30.4%, 3 dental lab. group 20.3%, production at own lab. group 8.7% 2. Cognitions about the respondent's job, About cognition of patient numvers, there were neither many nor few group 62.3%, few group 17.4%, many group 15.9%, too many group 4.4% in order.(P<.01) As compared with the ratio of dentists to patient prothetic treatment, there were moderate level group 46.4%, high level group 33.6%, low level group 18.8% in order.(P<.01) By job satisfaction of respondents, the highest percentage group was satisfied group 44.9%, neither astisfied nor disstified group 33.3%, dissatisfied group 14.5%, much satisfied group 7.3%(P<.01). As compared with the level of prosthetics price, the were moderate level group 71.0%, low level group 23.2%, high level group 5.8%(P<.01) 3. Satisfaction and assessment of dissatisfied factor of the fixed prosthetic appliance, As compared with the satisfaction of al prosthetic appliance, there were neither satisfied nor dissatisfied group 59.4%, satisfied group 20.3% dissatisfied group 18.8%, much satisfied group 1.5% in order.(P<.01). About precious and non precious metal crown and bridge, there were neither satisfied nor dissatisfied group 60.9%, satisfied group 24.6%, dissatisfied group 11.6%, much satisfied group 2.9% in order.(P<.01) The reat of respondent;s satisfaction about porcelain crown and bridge was as follow : neither satisfied nor dissatisfied group 43.5%, dissatisfied group 33.3%, satisfied group 21.7%, much satisfied group 1.5%(P<.01). The rate of respondent's dissatisfied factor item of precious and non precious metal crown and bridge was as follow : inadequate margin fit item 39.1% respondent, inadequate occlusion item 24.6%, inadequate adaptation item 23.2%, poor anat omic form item 15.9%, inadequate contact item 31.9%, improper polishing item 4.4%, the rest item 11.6% respectively. The rate of respondent's dissatisfied factor item of porcelain crown and bridge was as follow : inadequate margin fit item 52.2%, inadequate occlusion item 2.9%, inadequate adaptation item 10.1%, poor anatomic form item 11.6%, improper polishing item 1.5%, shade mismatching item 71%, the rest item 7.2% respectively. The rate of cognition of respondents’ about cause of dissatisfied factor on fixed prosthetic appliance by item was as follow : deficiency of sincerity item 55.1%, deficiency of knowledge about work item 47.8%, deficiency of experience item 15.9%, poor quality of using material item 5.8%, the rest item 2.9% respectively.

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Low Temperature Inducible Acid Tolerance Response in virulent Salmonella enterica serovar Typhimurium (병원성 Salmonella enterica serovar Typhimurium의 저온 유도성 산 내성 반응)

  • Song, Sang-Sun;Lee, Sun;Lee, Mi-Kyoung;Lim, Sung-Young;Cho, Min-Ho;Park, Young-Keun;Park, Kyeong-Ryang;Lee, In-Soo
    • Korean Journal of Microbiology
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    • v.37 no.3
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    • pp.228-233
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    • 2001
  • The acid tolerance response (ATR) of log-phase Salmouella enterica seroyar Typhimurium is induced by acid adaptation below pH4.5 and will protect cells against more severe acid. Two distinctive ATR systems in thisorganism are a log-phase and stationary-phase ATR in which acid adaptations trigger the synthesis of acid shockproteins (ASPs). We found that log-phase ATR system was strongly affected by environmental factor, low tem-perature, $25^{\circ}C$. Exposure to low temperature and mild acid has been shown to increase acid survival dra-matically, and this survival rate was showed higher than $37^{\circ}C$. Especially unadapted cells at $25^{\circ}C$ presented tenthousand folds survival increasing when compared with cells at $37^{\circ}C$. The degree of acid tolerance of rpoSwhich is blown to be required for acid tolerance more increase than $37^{\circ}C$. Even though AIR pattern of rpoSbetween unadapted and adapted was showed similar at pH 3.1, rpoS-dependent ATR system also has beendetected in low temperature because rpoSAp prevents sustained acid survival at $25^{\circ}C$. Therefore the resultssuggest low temperature ATR system requires rpoS-dependent and -independent both. To investigate the basisfor low temperature related ATR system, gene that was participated for low temperature acid tolerance (lat) wasscreened in virulent S. enterica serovar Typhimurium UKl Using the technique of P22- MudJ (Km, lacZ)-directed lacZ operon fusion, LF452 latA‥‥MudJ was isolated. The latA‥‥MudJ of S. enterica Typhimurium pre-vented low temperature acid tolerance response. Therefore latA is considered one of the important genes for acidadaptation.

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The Systemic Effects of Hypothermic and Normothermic Cardiopulmonary Bypass in Cardiac Surgery (심장수술시 저체온 체외순환과 정상체온 체외순환의 전신 효과에 관한 연구)

  • Park Jae Min;Cho Yong Gil;Hwang Yoon Ho;Lee Yang Haeng;Yoon Young Chul;Junng Hee Jae;Han Il Yong;Choi Seok Cheol;Cho Kwang Hyun
    • Journal of Chest Surgery
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    • v.38 no.1 s.246
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    • pp.29-37
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    • 2005
  • This study was prospectively designed to determine the physiologic effects of normothermic CPB and to compare its influences with hypothermic CPB. Material and Method: Thirty-six adult patients scheduled for el­ective cardiac surgery were randomly assigned to moderate hypothermic (hypothermic group nasopharyngeal tem­perature $26\~28^{\circ}C,\;n=18)$ ornormothermic (normothermic group, nasopharyngeal temperature > $35.5^{\circ}C\;n=18)$ CPB. Arterial blood samples were taken before CPB (Pre-CPB), 10 minutes after the start of CPB (CPB-10), and imme­diately after CPB stop (CPB-off) for determining total leukocyte counts, neuron-specific enolase (NSE), interleukin-6 (IL-6), endothelin-1 (ET-1), cortisol, troponin I (TNI), aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, blood urea nitrogen (BUN), and the pulmonary index $(Pi,\;PaO_{2}/FiO_{2}),$Other parameters such as urine output, mechanical ventilating period, ICU-staying period, postoperative complications and hospitalized days were also evaluated. Result: Total leukocyte counts, increased rate in NSE, in IL-6 and in cortisol at CPB-10 and CPB-off were significantly higher in normothermic group than in hyphothermic group. Urine output during CPB was lower in normothermic group than in hyphothermic group. The duration of mechanical ventilation, ICU-stay, and hospitalization were longer in normothermic group than in hyphothermic group. Conclusion: These findings sug­gested that normothermic CPB caused higher inflammatory and stress responses than hypothermic CPB during car­diac surgery using cold crystalloid cardioplegia. However, further studies with large number of cases should be carried out to validate this hypothesis.

Mantle Ultrastructure of the Spiny Top Shell, Batillus cornutus (Gastropoda: Turbinidae) (소라(Batillus cornutus) 외투막의 미세구조)

  • Jung, Gui-Kwon;Park, Jung-Jun;Jin, Young-Guk;Ju, Sun-Mi;Lee, Jae-Woo;Jung, Ae-Jin;Lee, Jung-Sick
    • The Korean Journal of Malacology
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    • v.24 no.1
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    • pp.41-50
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    • 2008
  • The histochemical characteristics and ultrastructure of the mantle in the spiny top shell, Batillus cornutus were described using light and electron microscopy. The simple epidermal layer wrapped on the top and bottom of the centrally located connective tissue. And then the epidermal layer were divided into the outer epidermal layer near a shell and the inner epidermal layer closed to the visceral mass. The connective tissue layer was composed of the collagen fiber muscularfiber bundle and hemolymph sinus. Mucous cells in the apical mantle contained acid and neutral mucopolysaccaride, and acidic carboxylated mucopolysaccaride in the mid and marginal mantle. The mantle thickness, epidermal layer thickness and hemolymph sinus area displayed a trend of reduction from the marginal zone to the apical zone. From TEM observation, it was possible to distinguish epithelium, ciliated cell, absorptive cell and secretory cell in the epidermal layer. The epithelia were columnar and the nucleus was elliptical. The free surface were covered with microvilli. The lateral membranes of epithelium was con nected with neighboring cells by the zonular occludens, zonular adherens and membrane interdigitation. Ciliated cell on free surface had cilia and microvilli, and numerous mitochondria in the apical cytoplasm. In the epidermal layer, it observed 2 type cells having absorptive function. The absorptive cells were columnar in shape, and contained microvilli, pinocytotic vesicles, mitochondria and lysosomes of various electron density. Secretory cells can be divided into four types (A, B, C, D) depending on the cell shape and characteristics of secretory granules. These cells were unicellular glands and had similar characteristics to previously reported on the mantle of the gastropod and bivalves.

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Effect of Temperature, Light Intensity and $CO_2$ Concentration on Photosynthesis and Respiration of Wasabia japonica Matsum (온도(溫度), 광도(光度) 및 $CO_2$의 농도(濃度)가 고추냉이의 광합성(光合成)과 호흡(呼吸)에 미치는 영향(影響))

  • Choi, Sun-Young;Lee, Kang-Soo;Eun, Jong-Seon
    • Korean Journal of Medicinal Crop Science
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    • v.3 no.3
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    • pp.181-186
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    • 1995
  • This study was carried out to know the effect of temperature, light intensity and $CO_2$ con­centration on photosynthesis and respiration in Wasabi (Wasabia japonica Matsum). The optimum temperature for photosynthesis in Wasabi was $17{\sim}20^{\circ}C$ and dark respiration rate was increased with the increasing of tem­perature from, $15 ^{\circ}C\;to\;30^{\circ}C$. Light compensation point was $6.0\;{\mu}E\;m^{-2}s^{-1}$ in Wasabi and $36.7\;{\mu}E\;m^{-2}s^{-1}$ in Corn, and light saturation point was $600{\mu}E\;m^{-2}s^{-1}$, similar in Wasabi and Corn. $CO_2$, compensation point was 67.3ppm in Wasabi and 11.6 ppm in Corn. Photorespiration rate in Wasabi leaf at $l000{\mu}E\;m^{-2}s^{-1}$ light intensity was 3.3 mg$CO_2$, $dm^{-2}hr^{-1}$, and then was gradually decreased as light intensity decreased. Stomatal frequency was about $76\;mm^{-2}$ on the adaxial surface and $623\;mm^{-2}$ on the abaxial surface, and the size of stomata was about 1$12{\mu}m$ on the adaxial surface and $17{\mu}m$ on the abaxial surface of the leaf.

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Die $Luftfrachtersatzbef{\ddot{o}}rderung$ (항공화물대체운송(航空貨物代替運送)에 관한 법적(法的) 문제(問題))

  • Jeon, Sam-Hyeon
    • The Korean Journal of Air & Space Law and Policy
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    • v.9
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    • pp.327-349
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    • 1997
  • Luftfrachtersatzverkehr ist der Transport von Luftfrachtgut von Flughafen zu Flughafen unter einem Luftfrachtbrief im $Oberfl{\ddot{a}}chentransport$ urn die erste und/oder letzte Teilstrecke einer als Gesamtstrecke vereinbarten $Luftfrachtbef{\ddot{o}}rderung$. These Strecken $f{\ddot{u}}hren$ von nationalen oder intemationalen $Flugh{\tilde{a}}fen$ zurn Zentralflughafen ($_"Hub"$) der Luftverkehrsgesellschaft bzw. in urngekehrter Richtung vom Zentralflughafen hin zu den einzelnen nationalen oder intemationalen $Flugh{\ddot{a}}fen$. Die Vorteile des Luftfrachtersatzverkehrs sind offenkundig, daher auch sein $st{\ddot{a}}ndiges$ Anwachsen. Allerdings bestand bei den Luftverkehrsgesellschaften jahrelang eine $gro{\ss}e$ Unsicherheit, wie dieser Luftverkehr, der eben nicht in der Luft $durchgef{\ddot{u}}hrt$ wird, rechtlich zu qualifizieren sei. Stellte die $Bef{\ddot{o}}rderung$ von $Luftfrachtg{\ddot{u}}tem$ auf der $Stra{\ss}e$ einen Bruch des $Luftbef{\ddot{o}}rderungsvertrages$ dar, so wie im Schadensfall die $Gesch{\ddot{a}digten$, Absender oder $Empf{\ddot{a}}nger$ des betreffenden Gutes, der Luftverkehrgesllschft auf Art. 18 Abs. 3 oder Art. 31 Warschauer Abkommen(WA) berufen? Folge dieser Unsicherheit war, $da{\ss}$ ${\ddot{u}}ber$ lange Jahre hinweg die Luftverkehrsgesellschaften sich scheuten, diese Frage einer gerichtlichen $Kl{\ddot{a}}rung$ $zuzuf{\ddot{u}}hren$, Eher war man geneigt, sich mit dem Anspruchsgegner $au{\ss}ergerichtlich$ zu vergleichen, selbst wenn dies bedeutete, $da{\ss}$ man sich nicht auf die $Haftungsbeschr{\ddot{a}}nkungen$ des Art. 22 WA berufen konnte, als ein Urteil zu erstreiten, welcher $m{\ddot{o}}glicherweise$ der Praxis der $Luftfrachtersatzbef{\ddot{o}}rderung$ einen - rechtlichen - Riegel vorgeschoben $h{\ddot{a}}tte$. Diese Unsicherheit ist jedoch durch die Entscheidung die erste und wohl auch bislang einzige $h{\ddot{o}}chstrichterliche$ Entscheidung zur $Luftfrachtersatzbef{\ddot{o}}rderung$ nicht nur in Deutschland, sondem soger in Europa. Die Luftverkehrsgesellschaften $k{\ddot{o}}nnen$ mit dieser Entscheidung gut leben. Bei emer $vertragsgem{\ddot{a}}{\ss}en$ $Luftfrachtersatzbef{\ddot{o}}rderung$ haftet der $Luftfrachtf{\ddot{u}}hrer$ $f{\ddot{u}}r$ $Sch{\ddot{a}}den$ $anl{\ddot{a}}{\ss}lich$ der mit dem Luftfahrzeug $ausgef{\ddot{u}}hrten$ Teilstrecke nach den Vorsschriften des Warschauer Abkommens und $f{\ddot{u}}r$ $Sch{\ddot{a}}den$ $anl{\ddot{a}}{\ss}lich$ der mit einem $Oberfl{\ddot{a}}chenbef{\ddot{o}}rderungsmittel$ $ausgef{\ddot{u}}hrten$ Teilstrecke nach den Vorschriften, welche $f{\ddot{u}}r$ das $tats{\ddot{a}}chlich$ eingesetzte ransportmittel $einschl{\ddot{a}}gig$ sind. Bei unbekanntem Schadensort haftet der $Luftfrachtf{\ddot{u}}hrer$ nach dem jeweils $sch{\ddot{a}}rfsten$ der in Betracht kommenden Rechte. Bei emer vertragwidrigen $Luftfrachtersatzbef{\ddot{o}}rderung$ haftet der $Luftfrachtf{\ddot{u}}hrer$ nach dem Recht des vereinbarten $Bef{\ddot{o}}rderungsmittels$, da sich auf dieses Recht der Vertragspartner des $Luftfrrachtf{\ddot{u}}hrers$ eingerichtet hatte. Der $Luftfrachtf{\ddot{u}}frer$ haftet aber auch nach dem Recht des $tats{\ddot{a}}chlich$ eingesetzten $Bef{\ddot{o}}rderungsmittels$, da er sich in dessen Haftungsordnung durch die einseitige Wahl des $Bef{\ddot{o}}rderungsmittels$ selbst hineingestellt hat. Bei unbekanntem Schadensort haftet der $Luftfrachtf{\ddot{u}}hrer$ nach dem jeweils $sch{\ddot{a}}rfsten$ der in Betracht kommenden Rechte.

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The Effects of Vitamin C on the Activity of Liver Enzymes and Hepatic Damage in Rats Treated with Radiation and Aflatoxin $B_1$ (Vitamin C가 방사선과 Aflatoxin $B_1$을 투여한 흰쥐의 간 기능 효소 활성 및 간 손상에 미치는 효과)

  • Kang, Jin-Soon
    • The Korean Journal of Food And Nutrition
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    • v.23 no.1
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    • pp.30-38
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    • 2010
  • This study was conducted to determine the effects of vitamin C on the activity of liver function enzymes and electromicrographic changes in white rats treated with aflatoxin $B_1(AFB_1)$ or X-ray and $AFB_1$. Six week-old male Sprague-Dawley rats were randomly divided into five groups: a control group, $AFB_1$ treated group, $AFB_1$ treated group with vitamin C, X-ray and $AFB_1$ co-treated group, X-ray and $AFB_1$ co-treated group with vitamin C. On the first day of the experiment, only one dose of X-rays was exposed to the entire liver at 1,500 cGy. Next, vitamin C was injected at 10 mg/kg body weight by intraperitoneal injection, followed 1 hr later by the administration of 0.4 mg/kg of $AFB_1$ by intraperitoneal injection. These treatments were then administered every three days over a period of 15 days. On the 16th day of treatments, the animals were sacrificed. Analysis of the activity of the liver function enzymes, GOT, ALK phatase and LDH, in the sera of rats revealed that they were somewhat increased by $AFB_1$ treatment, X-ray and $AFB_1$ co-treatment when compared to the control group. Furthermore, the activity of these enzymes decreased in response to administration of vitamin C. Especially, the levels of GOT were remarkably decreased in the $AFB_1$ treated group treated with vitamin C when compared to the group treated with $AFB_1$ alone(p<0.001). Electromicrographic analysis revealed cloudy swelling, necrosis, vesicular degeneration and fat accumulation of hepatocytes in response to treatment with $AFB_1$ or co-treatment with X-ray and $AFB_1$. However, the destruction of hepatic cells was considerably lower in the vitamin C-treated group. These results indicate that vitamin C had ameliorating effects on the hepatic cell damage.

Microbial Leaching of Iron from Magnetite (미생물을 이용한 자철석으로부터 철 침출에 관한 연구)

  • Roh, Yul;Oh, Jong-Min;Seo, Yong-Jae;Jang, Hee-Dong
    • Journal of the Mineralogical Society of Korea
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    • v.19 no.4 s.50
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    • pp.265-275
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    • 2006
  • It is in its infancy to use bacteria as a novel biotechnology for leaching precious and heavy metals from raw materials. The objective of this study was to investigate biogeochemical processes of iron leaching from magnetite reduction by iron-reducing bacteria isolated from intertidal flat sediments, southwestern part of Korea. Microbial leaching experiments were performed using commercial magnetite, Aldrich magnetite, in well-defined mediums with and without bacteria. Water soluble Fe production was determined by ICP analysis of bioleached samples in comparison to uninoculated controls, and the resulting precipitated solids were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The extent of iron leaching from magnetite in the aerobic conditions (Fe = 107 ppm) was higher than that in the anaerobic environments (Fe = 94 ppm). In the anaerobic conditions, Fe(III) in commercial magnetite was also reduced to Fe(II), but no secondary mineral phases were observed. Amorphous iron oxides formed in the medium under aerobic conditions where there was sufficient supply of oxygen from the atmosphere. SEM observation suggests that the reduction process involves dissolution-precipitation mechanisms as opposed to solid state conversion of magnetite to amorphous iron oxides. The ability of bacteria to leach soluble iron and precipitate amorphous iron oxides from crystalline magnetite could have significant implications for biogeochemical processes in sediments where Fe(III) in magnetite plays an important role in the largest pool of electron acceptor as well as the tool as a novel biotechnology for leaching precious and heavy metals from raw materials.

Enhancement of Immune Activities of Peptides from Asterias amurensis Using a Nano-encapsulation Process (나노 입자 불가사리 펩타이드의 면역 활성 증진)

  • Jeong, Hyang-Suk;Oh, Sung-Ho;Kim, Seoung-Seop;Jeong, Myoung-Hoon;Choi, Woon-Yong;Seo, Yong-Chang;Choi, Geun-Pyo;Kim, Jin-Chul;Lee, Hyeon-Yong
    • Korean Journal of Food Science and Technology
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    • v.42 no.4
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    • pp.424-430
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    • 2010
  • Immuno-modulatory activities of peptides from Asterias amurensis were investigated using a nano-encapsulation process. The molecular weights of the peptides in the range of 5-7 kDa were separated using Sephadex G-75 gel filtration. Eighty-five percent of the nano-particles were in the 300 nm range using dynamic light scattering. The cytotoxicity of the A. amurensis nano-particles against CCD-986sk human dermal fibroblast cells was 11.64% after adding 1.0 mg/mL of the samples, which was lower than that from the control (13.28% collagen). The secretion of $NO^-$ from macrophages was estimated as $40\;{\mu}M$ after adding 1.0 mg/mL of gelatin nano-particles, which was higher than the others. Prostaglandin $E_2$ production from UV-induced human skin cells decreased greatly to 860 pg/mL after adding 1.0 mg/mL of the samples. Confocal microscopy revealed that nano-particles effectively penetrated the cells within 1 hour. From these results, we consider that nano-encapsulation of the peptides from A. amurensis can improve their biological functions.

The Anticancer Effect and Mechanism of Photodynamic Therapy Using 9-Hydroxypheophorbide-a and 660 nm Diode Laser on Human Squamous Carcinoma Cell Line. (9-hydroxypheophorbide-a와 660 nm 다이오드 레이저를 이용한 광역학치료의 항암효과와 치료기전에 대한 연구)

  • Ahn, Jin-Chul
    • Journal of Life Science
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    • v.19 no.6
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    • pp.770-780
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    • 2009
  • A new photosensitizer, 9-Hydroxypheophorbide-a (9-HpbD-a), was derived from Spirulina platensis. We conducted a series of experiments, in vitro and in vivo, to evaluate the anticancer effect and mechanism of photodynamic therapy using 9-HpbD-a and 660 nm diode lasers on a squamous carcinoma cell line. We studied the cytotoxic effects of pheophytin-a, 9-HpbD-a, 9-HpbD-a red and 660 nm diode lasers in a human head and neck cancer cell line (SNU-1041). Cell growth inhibition was determined by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay. The effects of 9-HpbD was higher than those of 9-HpbD-a red or pheophytin-a in PDT. We then tested the cytotoxic effects of 9-hydroxypheophorbide-a (9-HpbD-a) in vitro. The cultured SNU-I041 cells were treated with serial concentrations of 9-HpbD-a followed by various energy doses (0, 0.1, 0.5, 3.2 J/$cm^{2}$) and by various interval times (0, 3, 6, 9, 12 hr) until laser irradiation, then MTT assay was applied to measure the relative inhibitory effects of photodynamic therapy (PDT). Optimal laser irradiation time was 30 minutes and the cytotoxic effects according to incubation time after 9-HpbD-a treatment increased until 6 hours, after which it then showed no increase. To observe the cell death mechanism after PDT, SUN-I041 cells were stained by Hoechst 33342 and propidium iodide after PDT, and observed under transmission electron microscopy (TEM). The principal mechanism of PDT at a low dose of 9-HpbD-a was apoptosis, and at a high dose of 9-HpbD-a it was necrosis. PDT effects were also observed in a xenografted nude mouse model. Group I (no 9-HpbD-a, no laser irradiation) and Group II (9-HpbD-a injection only) showed no response (4/4, 100%), and Group III (laser irradiation only) showed recurrence (1/4,25%) or no response (3/4, 75 %). Group IV (9-HpbD-a + laser irradiation) showed complete response (10/16, 62.5%), recurrence (4/16, 25%) or no response (2/16, 12.5%). Group IV showed a significant remission rate compared to other groups (p<0.05). These results suggest that 9-HpbD-a is a promising photosensitizer for the future and that further studies on biodistribution, toxicity and mechanism of action would be needed to use 9-HpbD-a as a photosensitizer in the clinical setting.