• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.1-33
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• 1997

The objective of this study was to analyze the in vitro and in vivo corrosion products of low and high copper amalgams. The four different types of amalgam alloy used in this study were Fine cut, Caulk spherical, Dispersalloy, and Tytin. After each amalgam alloy and Hg were triturated according to the directions of the manufacturer by means of the mechanical amalgamator(Amalgam mixer. Shinhung Co. Korea), the triturated mass was inserted into a cylindrical metal mold which was 12mm in diameter and 10mm in height. The mass was condensed by 150Kg/cm compressive force. The specimen was removed from the mold and aged at room temperature for about seven days. The standard surface preparation was routinely carried out by emery paper polishing under running water. In vitro amalgam specimens were potentiostatically polarized ten times in a normal saline solution at $37^{\circ}C$(potentiostat : HA-301. Hukuto Denko Corp. Japan). Each specimen was subjected to anodic polarization scan within the potential range -1700mV to+400mV(SCE). After corrosion tests, anodic polarization curves and corrosion potentials were obtained. The amount of component elements dissolved from amalgams into solution was measured three times by ICP AES(Inductive Coupled Plasma Atomic Emission Spectrometry: Plasma 40. Perkim Elmer Co. U.S.A.). The four different types of amalgam were filled in occlusal and buccal class I cavities of four human 3rd molars. After about five years the restorations were carefully removed after tooth extraction to preserve the structural details including the deteriorated margins. The occlusal surface, amalgam-tooth interface and the fractured surface of in vivo amalgam corrosion products were analyzed. In vivo and in vitro amalgam specimens were examined and analyzed metallographically by SEM(Scanning Electron Microscope: JSM 840. Jeol Co. Japan) and EDAX(Energy Dispersive Micro X-ray Analyser: JSM 840. Jeol Co. Japan). 1. The following results are obtained from in vitro corrosion tests. 1) Corrosion potentials of all amalgams became more noble after ten times passing through the in vitro corrosion test compared to first time. 2) After times through the test, released Cu concentration in saline solution was almost equal but highest in Fine cut. Ag and Hg ion concentration was highest in Caulk spherical and Sn was highest in Dispersalloy. 3) Analyses of surface corrosion products in vitro reveal the following results. a)The corroded surface of Caulk spherical has Na-Sn-Cl containing clusters of $5{\mu}m$ needle-like crystals and oval shapes of Sn-Cl phase, polyhedral Sn oxide phase. b)In Fine cut, there appeared to be a large Sn containing phase, surrounded by many Cu-Sn phases of $1{\mu}m$ granular shapes. c)Dispersalloy was covered by a thick reticular layer which contained Zn-Cl phase. d)In Tytin, a very thin, corroded layer had formed with irregularly growing Sn-Cl phases that looked like a stack of plates. 2. The following results are obtained by an analysis of in vivo amalgam corrosion products. 1) Occlusal surfaces of all amalgams were covered by thick amorphous layers containing Ca-P elements which were abraded by occlusal force. 2) In tooth-amalgam interface, Ca-P containing products were examined in all amalgams but were most clearly seen in low copper amalgams. 3) Sn oxide appeared as a polyhedral shape in internal space in Caulk spherical and Fine cut. 4) Apical pyramidal shaped Sn oxide and curved plate-like Sn-Cl phases resulted in Dispersalloy. 5) In Tytin, Sn oxide and Sn hydroxide were not seen but polyhedral Ag-Hg phase crystal appeared in internal space which assumed a ${\beta}_l$ phase.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.664-668
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• 2011

Spherical alumina precursors represented by $AlO_xCl_y(OH)_z$, 30~200 nm in particle diameter, were prepared by partial hydrolysis of $AlCl_3$ vapor in a 500 ml reactor. Investigated on the particle morphology and size were the effects of the reaction time, the stirring speed and the reaction temperature. The particle morphology and size was insensitive to the reaction time in the range 20 to 300 s. The variation of the stirring speed from 0 to 300 and 800 rpm showed that the particle size was the largest at 0 rpm. As the temperature was varied from 180 to 190, 200, $140^{\circ}C$, the particle size showed a maximum at $190^{\circ}C$. By calcination of the as-produced particles at $1,200^{\circ}C$ for 6h with a heating rate of $10^{\circ}C$/min, ${\alpha}$-alumina particles 45 nm in surface area equivalent diameter were obtained. The particle shape after calcination turned wormlike due to sintering between neighboring particles. A rapid calcination at $1400^{\circ}C$ for 0.5 h with a higher heating rate of $50^{\circ}C$/min reduced the sintering considerably. An addition of $SiCl_4$ or TMCTS(2,4,6,8-tetramethylcyclosiloxane) to the $AlCl_3$ reduced the sintering effectively in the calcination step; however, peaks of ${\gamma}$ or mullite phase appeared. An addition of $AlF_3$ to the particles obtained from the hydrolysis resulted in a hexagonal disc shaped alumina particles.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2000.11a
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• pp.3-4
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• 2000

Many researchers are interested in the synthesis and characterization of carbon nitride and diamond-like carbon (DLq because they show excellent mechanical properties such as low friction and high wear resistance and excellent electrical properties such as controllable electical resistivity and good field electron emission. We have deposited amorphous carbon nitride (a-C:N) thin films and DLC thin films by shielded arc ion plating (SAIP) and evaluated the structural and tribological properties. The application of appropriate negative bias on substrates is effective to increase the film hardness and wear resistance. This paper reports on the deposition and tribological OLC films in relation to the substrate bias voltage (Vs). films are compared with those of the OLC films. A high purity sintered graphite target was mounted on a cathode as a carbon source. Nitrogen or argon was introduced into a deposition chamber through each mass flow controller. After the initiation of an arc plasma at 60 A and 1 Pa, the target surface was heated and evaporated by the plasma. Carbon atoms and clusters evaporated from the target were ionized partially and reacted with activated nitrogen species, and a carbon nitride film was deposited onto a Si (100) substrate when we used nitrogen as a reactant gas. The surface of the growing film also reacted with activated nitrogen species. Carbon macropartic1es (0.1 -100 maicro-m) evaporated from the target at the same time were not ionized and did not react fully with nitrogen species. These macroparticles interfered with the formation of the carbon nitride film. Therefore we set a shielding plate made of stainless steel between the target and the substrate to trap the macropartic1es. This shielding method is very effective to prepare smooth a-CN films. We, therefore, call this method "shielded arc ion plating (SAIP)". For the deposition of DLC films we used argon instead of nitrogen. Films of about 150 nm in thickness were deposited onto Si substrates. Their structures, chemical compositions and chemical bonding states were analyzed by using X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and infrared spectroscopy. Hardness of the films was measured with a nanointender interfaced with an atomic force microscope (AFM). A Berkovich-type diamond tip whose radius was less than 100 nm was used for the measurement. A force-displacement curve of each film was measured at a peak load force of 250 maicro-N. Load, hold and unload times for each indentation were 2.5, 0 and 2.5 s, respectively. Hardness of each film was determined from five force-displacement curves. Wear resistance of the films was analyzed as follows. First, each film surface was scanned with the diamond tip at a constant load force of 20 maicro-N. The tip scanning was repeated 30 times in a 1 urn-square region with 512 lines at a scanning rate of 2 um/ s. After this tip-scanning, the film surface was observed in the AFM mode at a constant force of 5 maicro-N with the same Berkovich-type tip. The hardness of a-CN films was less dependent on Vs. The hardness of the film deposited at Vs=O V in a nitrogen plasma was about 10 GPa and almost similar to that of Si. It slightly increased to 12 - 15 GPa when a bias voltage of -100 - -500 V was applied to the substrate with showing its maximum at Vs=-300 V. The film deposited at Vs=O V was least wear resistant which was consistent with its lowest hardness. The biased films became more wear resistant. Particularly the film deposited at Vs=-300 V showed remarkable wear resistance. Its wear depth was too shallow to be measured with AFM. On the other hand, the DLC film, deposited at Vs=-l00 V in an argon plasma, whose hardness was 35 GPa was obviously worn under the same wear test conditions. The a-C:N films show higher wear resistance than DLC films and are useful for wear resistant coatings on various mechanical and electronic parts.nic parts.

• Journal of Korean Academy of Nursing
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• v.1 no.1
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• pp.85-94
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• 1970

This is a study of 21 tuberculosis patients receiving medical treatment at the Public Health Center in Kyongi Do, Pu Chun Gun and at the General Hospital. The results cover the findings of the period from May, 1969 to November 1970. The information obtained is based on personal interviews with the patients, and symptomatic diagnosis made from observations. The following statistics when not equalling 100% contain only the responses of the two extremes in each case. The findings of the research are as follows: 1. 52.3% of the patients in the study are males and 47.7% are females. 28.6% of the subjects are between 20 and 29 years of age and an equal percent are between 30 and 39 years. 2. 47.5% of the subjects had graduated from primary school, while only 4.8% had graduated from high school. 3. 57.1% of the patients said they had no religions beliefs, while 4.8% professed to being Buddhists or believing in superstition. 4. 47.3% of the people said they were unemployed, while 4.8% classified themselves as labourers. 5. In response to how tuberculosis was first detected in their respective cases, 52.6% became aware of their disease through X-ray results, while 4.8% were discovered to have tuberculosis when being treated for other diseases at the hospital. 6. When asked how many of the patients knew anything about their disease when treated, 57.1% knew nothing about tuberculosis when they received treatment, while 42.9% had some knowledge of the disease. 7. Of those who knew something about tuberculosis, 61.9% learned about from doctors and nurses, while 4.8% learned from other people. 8. 57.1% of the patients knew that tuberculosis is a communicable disease, while 42.9% did not know. 9. 52.4% of the patients did not know the cause of tuberculosis while 4.9% believed the disease was caused by a curse. 10. When asked about the extent of treatment, 52.4% responded that they had undergone continuous treatment, while 4.8% had not received treatment. 11.The reasons given for not continuing treatment were the following: economic factors 55.6%; side reactions to the treatment, lack of knowledge of how to get treatment, of the need for treatment, or of the positive effects of treatment 11.1%. 12. 61.9% of the subjects usually took the medical treatment at home, 9.5% took it in the mountains or at the beach. 13. 42.9% of the patients received drugs for treatment at the local public health center, while 4.8% received them at the hospital 14. 33.3% of the patients received P.A.S＋I.N.H.＋S.M. for treatment of tuberculosis, while 4.8% received P.A.S.＋S.M.. and some secondary drug. 15. Of the patients who took some extra medicine for tuberculosis, 38.1% took a Chinese drug, while 9.5% took herb medicine. 16. 38.1% of the patients had continued treatment for three years, 4.8% had interrupted the treatment. 17. When asked about the development of the disease after treatment, the patients gave the following information: after one month, 90.5% thought the treatment helped, while 9.5% weren't sure; after one year, 55.6% thought it was good, while 5.5% thought it was not; after three years, 63.6% had a very bad condition. while 4.8% didn't know. 18. 61.9% of the patients were unconcerned about covering their mouths when they coughed, while 38.1% covered their mouths. 19. 57.2% were unconcerned they spit, while 23.8% spit into a waste basket. 20. 66.7% were unconcerned about sterilizing tableware, while 9.5% handled it separately. 21. 66.7% were unconcerned about ventilating their room, while 9.5% ventilated the room twice a week.

• Korean journal of food and cookery science
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• v.5 no.2
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• pp.63-73
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• 1989

Family meals are very important for physical and mental health of family mebers. The purpose of this study is to contribute to change the habitual and unconscious cooking methods of housewives into more scientific moth(Ids. In order to achieve this purpose, this study tried to find out the degree to which housewives applied their knowledge of nutition and foods to actual behavior in purchasing. A special form of questionaire was prepared and distributed to 502 housewives in Seoul from Feb.8th to 22nd in 1989. The results were as follows: 1. Mean (score) of their nutritional knowledge was 14 7; if seems to be comparatively higher. 2. When they purchased food materials, their husbands' favor was the first consideration. Particularly, freshness was the first considered in purchasing meat, fishes, fruits, and vegetables. And Nutrition was so in case of seaweeds, oil, and fat. 3. For the most part, they cook three or four Subsidiary dishes for a meal. If they cooked one or two they chose to cook vegetables. If three or four they added meat and fishes. If more than four, they used various food materials.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.7
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• pp.1023-1029
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• 2007

Inhibins participate in the regulation of pituitary follicle-stimulating hormone synthesis and secretion, follicular maturation and steroidogenesis in the female. Inhibin ${\beta}_A$ gene (INHBA) was studied as a candidate gene for the prolificacy of sheep. Single nucleotide polymorphisms of the entire coding region and partial 3' untranslated region of INHBA were detected by PCR-SSCP in two high fecundity breeds (Small Tail Han and Hu sheep) and six low fecundity breeds (Dorset, Texel, German Mutton Merino, South African Mutton Merino, Chinese Merino and Corriedale sheep). Only the PCR products amplified by primers 3, 4 and 5 displayed polymorphisms. For primer 3, genotype CC was only detected in Chinese Merino sheep, genotype AA was detected in the other seven sheep breeds. Genotype BB was only detected in Hu sheep. Only Hu sheep displayed polymorphism. Eight or four nucleotide mutations were revealed between BB or CC and AA, respectively, and these mutations did not result in any amino acid change. For primer 4, genotypes EE, EG and GG were detected in Dorset and German Mutton Merino sheep, genotypes EE, EF and FF were detected in Chinese Merino sheep, only genotype EE was detected in the other five sheep breeds. Only Dorset, German Mutton Merino and Chinese Merino sheep displayed polymorphism. Sequencing revealed one nucleotide mutation ($114G{\rightarrow}A$) of exon 2 of INHBA gene between genotype FF and genotype EE, and this mutation did not cause any amino acid change. Another nucleotide change ($143C{\rightarrow}T$) was identified between genotype GG and genotype EE, and this mutation resulted in an amino acid change of $serine{\rightarrow}leucine$. For primer 5, genotypes KK and KL were detected in German Mutton Merino and Corriedale sheep, genotypes KK, LL and KL were detected in the other six sheep breeds. Genotype MM was only detected in Hu sheep. All of these eight sheep breeds displayed polymorphism. Sequencing revealed one nucleotide mutation ($218A{\rightarrow}G$) of exon 2 of the INHBA gene between genotype LL and genotype KK, and nine nucleotide mutations between genotype MM and genotype KK. These mutations did not alter amino acid sequence. The partial sequence (395 bp for exon 1 and 933 bp for exon 2) of the INHBA gene in Small Tail Han sheep (with genotype KK for primer 5) was submitted into GenBank (accession number EF192431). Small Tail Han sheep displayed polymorphisms only in the fragment amplified by primer 5. The Small Tail Han ewes with genotype LL had 0.53 (p<0.05) or 0.63 (p<0.05) more lambs than those with genotype KL or KK, respectively. The Small Tail Han ewes with genotype KL had 0.10 (p>0.05) more lambs than those with genotype KK.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.9
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• pp.631-637
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• 2003

We have evaluated structural and electric, ferroelectric properties of PZT(30/70) thick film prepared by using 1,3-propanediol based sol-gel method on Pt/Ti/SiO$_2$/Si substrates. Rapid thermal annealing (RTA) is used to reduce the thermal stress and final furnace annealing is processed at $650^{\circ}C$. As the results of SEM analysis, we find that we get 350 nm in thickness for one coating and 1 $\mu$m for three times of coating. In the results of C-D analysis at 1 kHz, dielectric constant ($\varepsilon$$_{r}$) and dissipation factor were 886 and 0.03, respectively. C-V curve is shaped as a symmetrical butterfly. Leakage current density at 200 kV/cm is 1.23${\times}$10$^{-5}$ A/cm$^2$ and in the results of hysteresis loops measured at 150 kV/cm, the remnant polarization (P$_{r}$) and the coercive field (E$_{c}$) are 33.8 $\mu$C/cm$^2$ and 56.9 kV/cm, respectively. PZT(30/70) thick film exhibits relatively good ferroelectric, electric properties.s..

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.28-28
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• 1992

브라디키닌은 체내에서 강력한 혈관 확장 작용을 일으키는 autacoid(local hormone)로서 혈압의 항상성 유지, 모세혈관 투과성 증진, 염증 및 통증 반응 등에 관여하고 여러 장관 평활근을 수축시킨다. 또한 septic 혹은 endotoxic shock의 여러 원인 물질로도 생각되어진다. 최근 rhinovirus로 인한 감기의 제증상 원인 물질로도 브라디키닌이 주목을 받고있다. 이와같이 브라디키닌온 다양한 질병에 있어 중요한 원인 물질로 여겨지므로 브라디키닌 길항제들은 한두 질병의 치료제로 개발될 가능성이 높음이 강력히 제시되고 있는 실정이다. 이의 개발을 위해서 브라디키닌 수용체에 대한 연구는 필수적이라고 할 수 있다. 본 연구는 두 부분으로 나누어 진행중인데 첫째, 이제까지 보고된 브라디키닌 길항 물질들은 대부분이 브라디키닌의 특정 아미노산 잔기를 치환시킨 펩타이드 유도체로서 이들을 경구 투여시 peptidase어 의하여 쉽게 분해되고 또한 부분적인 효능제 활성을 갖는 불리한 점을 감안하여, 비펩타이드성 브라디키닌 길항제를 개발할 목적으로 한방 및 민간에서 자주 사용되어온 생약중에 브라디키닌 작용에 선택적 길항효과가 있는 물질을 검색한 바 활성을 보인 황금으로부터 작용 성분을 추적중에 있다. 둘째, 브라디키닌 수용체를 순수하게 분리 정제하기 위한 첫 단계로서 이 수용체의 결합시험(binding assay) 방법을 확립하고 더불어 여러 조직내(흰쥐의 여러 기관, 토끼 및 사람의 신장)의 브라디키닌 수용체의 분포를 파악하는 일이다. 횐쥐 조직의 실험 결과로부터 신장에 브라디키닌 수용체가 많이 분포함을 확인되었고 향후 토끼 신장으로부터 동수용체를 분리하고자 한다. 또한 토끼 신장의 근위세뇨관일차배양세포을 이용하여 브라디키닌의 신장에서의 작용기전도 살펴보고 있다.+}$, $Na^{+}$, NH$_{4}$$^{+}$ 및 H$^{+}$) 수용액 메디움에서의 Cd(II), Mg(II) 및 Zn(II)의 Dowex 1-X8, Cl$^{-}$ 수지에 대한 흡착은 역시 어떤 메디움에서도 Cd(II) 흡착이 제일 크며, 다음이 Zn(II) 이고 착이온을 형성않는 Mg(II)이 제일 작았다. 한편 메디움 종류별 D값의 크기순위는 H$^{+}$>K$^{+}$> $Na^{+}$>NH$_{4}$$^{+}$이였다. 메디움의 종류에 따라 D값의 차이가 나는 것은 금속이온의 착이온 형성과 금속이온의 용액내에서의 이온종의 상태와 관련이 있다고 생각된다. 마. MCl(M:K$^{+}$, $Na^{+}$, NH$_{4}$$^{+}$ 및 H$^{+}$)과 MNO$_{3}$ 용리액에 의한 Cd(II), Mg(II) 및 Zn(II)의 용리는 예상한 바와 같이 MCl에서 작은 Dv 값을 갖는데, 이것은 CdCl$_{4}$$^{2-}$ 착이온을 형성하거나 ZnCl$_{4}$$^{2-}$ , ZnCl$_{3}$$^{-}$같은 이온과 MgCl$^{+}$, MgCl$_{2}$같은 이온종을 형성하기 때문인것 같다. 한편 어떠한 용리액에서던지 NH$_{4}$$^{+}$의 경우

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.12
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• pp.1632-1638
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• 2010

Two experiments with growing pigs were conducted to investigate the effects of two distinct multienzyme preparations on nutrient digestibility, growth performance and blood profiles. In Exp. 1, a total of 96 pigs ($29.7{\pm}0.69\;kg$) were utilized in a 42-day performance and digestibility trial using four dietary treatments: CON (control diet), ENDO (control+0.10% Endopower), NSPase1 (control+0.10% NSPase) and NSPase2 (control+0.20% NSPase). Endopower was a commercial multienzyme preparation which contained ${\alpha}$-galactosidase, galactomannase, xylanase and ${\beta}$-glucanase. NSPase mainly contained ${\alpha}$-1,6-${\beta}$-galactosidase, ${\beta}$-1,4-mannanase and ${\beta}$-1,4-mannosidase. There were six replication pens per treatment with four pigs per pen. Pigs fed NSPase1 diet had a higher ADG (p<0.05) and G:F (p<0.05) than those fed the control diet. There were no significant differences in growth performance among the multienzyme treatments (p>0.05). Compared with CON, apparent digestibility of DM was increased (p<0.05) by ENDO treatment. N digestibility was improved (p<0.05) in response to multienzyme treatments during the experimental period. Blood urea nitrogen (BUN) was higher (p<0.05) in ENDO treatment than in CON and NSPase1 treatments at the end of the experiment, while the glucose level improved (p<0.05) due to ENDO and NSPase2 treatments. In Exp. 2, four ileal-cannulated, growing barrows ($20.17{\pm}1.31\;kg$) were housed in individual metabolism crates and randomly assigned to 1of 4 treatments (same as Exp. 1) within a $4{\times}4$ Latin square design. Enzyme supplementations improved the majority of apparent ileal amino acid digestibilities (p<0.05). It is concluded that the supplementation of NSPase1 improved growth performance as well as N digestibility and partially improved apparent ileal amino acid digestibility in growing pigs fed a diet based on corn and soybean meal.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.649-659
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• 2011

To examine the anti-cancer effects of Lepidium virginicum L., the anti-proliferative and pro-apoptotic effects of a water extract of L. virginicum leaves (WELVL) and of L. virginicum roots (WELVR) were investigated in HCT116 human colon carcinoma cells. The treatment of HCT116 cells with WELVL and WELVR resulted in the inhibition of growth and morphological changes in a concentration-dependent manner by inducing apoptosis. The growth inhibition and apoptosis induction by WELVR was stronger than that of WELVL thus, we determined that WELVR was the more optimal extract for this study. The increased apoptotic events in HCT116 cells caused by WELVR were associated with an up-regulation of Fas ligand, Bax, and Bad expression, a down-regulation of Bcl-2, Bcl-$_XL$, and Bid expression, and a decrease in the mitochondrial membrane potential (MMP, ${\Delta}{\psi}m$). WELVR treatment induced the proteolytic activation of caspase-3, -8, and -9, and the degradation of caspase-3 substrate proteins, such as poly (ADP-ribose) polymerase (PARP), ${\beta}$-catenin, and phospholipase C-${\gamma}1$ (PLC-${\gamma}1$). In addition, apoptotic cell death induced by WELVR was correlated with a down-regulation of inhibitors of the apoptosis protein (IAP) family, such as the X-linked inhibitor of apoptosis protein (XIAP), cIAP-1, and cIAP-2. These findings suggest that the WELVR-induced inhibition of cell proliferation is associated with the induction of apoptotic cell death. WELVR may be a potential chemotherapeutic agent for the control of HCT116 human colon carcinoma cells.