• Title/Summary/Keyword: mineral concentrations

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Comparison between phosphorus absorption coefficient and Langmuir adsorption maximum (전토양(田土壤) 인산(燐酸)의 흡수계수(吸收係數)와 Langmuir 최대흡착량(最大吸着量)과의 비교연구(比較硏究))

  • Ryu, In Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.8 no.1
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    • pp.1-17
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    • 1975
  • Laboratory experiments on the phosphorus adsorption by soil were conducted to evaluate the parameters for determination of phosphorus adsorption capacity of soil, which serve as a basis for establishing the amount of phosphorus required to improve newly reclaimed soil and volcanic ash soil. The calculated Langmuir adsorption maxima varied from 6.2-32.9, 74.7-90.4 and 720-915mg p/100g soil for cultivated soils, non-cultivated soils, and volcanic ash soils respectively. The phosphorus absorption coefficient ranged from 116-179, 161-259 and 1,098-1,205mg p/100g soil for cultivated soils, non-cultivated soils, and volcanic ash soils respectively. The ratio of the phosphorus absorption coefficient to Langmuir adsorption maximum was low in soils of high phosphorus adsorption capacity (1.3-1.5) and high in soils of low phosphorus adsorption capacity (2.2-18.7). Changes in the amount of phosphurus adsorption induced by liming and preaddition of phosphorus were hadly detected by the phosphorus absorption coefficient, which is measured using a test solution with a relatively high phosphorus concentration. The Langmuir adsorption maximum was a more sensitive index of the phosphorus adsorption capacity. The Langmuir adsorption maxima of the non-cultivated soils, which were treated with an amount of calcium hydroxide equivalent to the exchangeable Al and incubated ($25-30^{\circ}C$) for 40 days at field capacity, were lower than the original soils. The change in the adorption maximum on incubation following the liming of soils was insignificant for other soils. The secondary adsorption maximum of soils, which received phosphorus equivalent to the Langmuir adsorption maximum of the limed soils incubated ($25-30^{\circ}C$) for 50 days at held capacity, was 74.5, 5.6 and 23.8% of the primary adsorption maximum for volcanic ash soils, non-cultivated soils, and cultivated soils respectively. The amount of phosphorus adsorbed by soils increased quadratically with the concentration of phosphorus solution added to the soils. The amount of phosphorus adsorbed by 5-g soil samples from 100ml of 100- and 1,000mg p/l solution for the mineral soils and volcanic ash soils respectively was found to be close to the Langmuir adsorption maximum. The amount of the phosphorus adsorbed at these concentrations is defined as a saturation adsorption maximum and proposed as a new parameter for the phosphorus adsorption capacity of the soil. The evaluation of the phosphorus adsorption capacity by the saturation adsorption maximum is regarded as a more practical method in that it obviates the need for the various concentrations used for the determination of the Langmuir adsorption maximum.

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Studies on the Effects of Antler Extract in Osteoporosis-Induced Rats I. Effects of Antler Extract on Hormones, Ca, P and ALP Levels in Osteoporosis-Induced Rats (녹용 추출물 투여가 골다공증 유발 Rat 에 미치는 효과에 관한 연구 I. 녹용 추출물 투여가 골다공증 유발 Rat 의 혈청내 호르몬, Ca, P, ALP 수준에 미치는 영향)

  • Kim, S. K;Kim, S. W.;Kim, M. S.
    • Korean Journal of Animal Reproduction
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    • v.24 no.2
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    • pp.179-188
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    • 2000
  • The present study was carried out in order to investigate the effects of antler extract on hormone concentration, Ca, P and alkaline phosphatase (ALP) levels in ovariectomized rats. Rats were ovariectomized bilaterally and were fed up with Ca- and P-free diet in order to induce osteoporosis. Osteoporosis was determined by the extent of density of bone mineral and lowering the concentrations of serum Ca and P. Male or female antler extract were administrated for 5 weeks to elucidate the protective and therapeutic effects for osteoporosis. The serum concentrations of estradiol, progesterone, calcitonin, osteocalcin, Ca and P, and the activities of ALP of ovariectomized rats were examined for 5 weeks. 1. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of the serum estradiol of the ovariectomized rat significantly decreased from 40.50$\pm$3.34 pg/$m\ell$ to 20.80$\pm$1.86 pg/$m\ell$ for 5 weeks, the levels of serum estradiol were a signigicant lower than those of control group (49.50$\pm$2.70~50.80$\pm$3.l3 pg/$m\ell$). 2. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of serum progesterone were didn't show significant differences. 3. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of serum calcitonin were a little higher than those of control group (0.64$\pm$0.03 ~0.68$\pm$0.04 pg/$m\ell$). 4. After administration of female or male antler extract to osteoporosis-induced rats at the doses of 625 mg/kg and 1,250 mg/kg, respectively, the levels of serum osteocalcin were little higher than those of control groups (0.28$\pm$0.02~0.31$\pm$0.02 ng/$m\ell$). In addition, the levels of serum osteocalcin of female antler extract administered group were little higher than those of male antler extract administered group. 5. The levels of serum Ca and P in osteoporosisinduced rats, administered with male or female antler extract, were little higher than those of control group. However, the levels of serum Ca and P in ovariectomized rats were significantly higher than those of control group (p<0.05). 6. After administration of female or male antler extract to osteoporosis-induced rats, the activities of serum ALP increased compared with those of normal control group. There were significant differences between the serum ALP activities of FA 1,250 and 625 groups (p<0.05). These findings suggest a possible protective and therapeutic effects of female or male antler extract against bone loss in ovariectomized rats, associated with a significant increase of serum estradiol level.

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Antioxidative Activity of Aralia elata Shoot and Leaf Extracts (두릅 순 및 잎 추출물의 항산화 효과)

  • Cha, Jae-Young;Ahn, Hee-Young;Eom, Kyung-Eun;Park, Bo-Kyung;Jun, Bang-Sil;Cho, Young-Su
    • Journal of Life Science
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    • v.19 no.5
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    • pp.652-658
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    • 2009
  • The comparative activities of aqueous, ethanol, and methanol extracts from Aralia elata shoot (AES) and leaf (AEL) were tested by in vitro experimental models of linoleic acid peroxidation by thiocyanate and thiobarbituric acid (TBA) methods and scavenging activities of free radicals by DPPH (${\alpha}$,${\alpha}$'-diphenyl-${\beta}$-picrylhydrazyl). In addition, bio-active materials (phenolic compounds and minerals) were also measured. The extract yield of each solvent extracted from AES and AEL was 3.08% and 3.13% in aqueous, 0.58% and 0.66% in ethanol, and 0.81% and 1.73% in methanol, respectively. The highest extract yield was found in the aqueous extract from AEL. Major mineral contents (mg%) of AES and AEL were 575.7 and 759.3 in Ca, 353.5 and 330.0 in K, and 31.3 and 31.0 in Mg, respectively. The highest free radical scavenging activity was found in the aqueous extract by 28.69% at 0.1% additional level from AES and in the methanol extract by 92.36% at 0.1% additional level from AEL. Free radical scavenging activity was stronger in AEL than in AES. In antioxidative activities determined by thiocyanate and TBA methods against lipid peroxidation using linoleic acid, ethanol extracts from AEL showed the highest antioxidative activity at all treatment concentrations. These results may provide the basic data to understand the biological activities of bio-active materials derived from AES and AEL.

Effect of Pine (Pinus densiflora) Needle Extracts on Synthesis of Collagen in Osteoblastic MC3T3-E1 Cells (적송잎 추출물이 조골세포의 collagen 합성에 미치는 영향)

  • Jeon, Min-Hee;Kim, Young-Kyoung;Park, Yong-Soo;Hwang, Hyun-Jung;Kim, Sung-Gu;Lee, Sang-Hyeon;Choi, In-Soon;Kim, Mi-Hyang
    • Journal of Life Science
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    • v.20 no.4
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    • pp.607-613
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    • 2010
  • Osteoporosis is a disease involving a decrease in bone mineral density and an increased risk of fractures. The MC3T3-E1 pre-osteoblastic cell line is a well-accepted model of osteogenesis in vitro. Pine needles have long been used as a traditional health-promoting medicinal food in Korea. In this study, MTT assay, the alkaline phosphatase (ALP) activity and collagen synthesis of osteoblast cells were investigated to determine the effects of pine needle extracts on cell proliferation and differentiation. Pine needle extracts were prepared using hexane, ethanol and water. The effects of the pine needle extracts were examined by comparing the results with those of commercial agents, such as proanthocyanidin. The MC3T3-E1 cells exposed to proanthocyanidin showed increased proliferation in a concentration-dependent manner. The cells exposed to the hexane extract showed a similar increase in proliferation to that observed with proanthocyanidin. The hexane extract showed the highest ALP activity. Moreover, a supplement of pine needle extracts induced collagen synthesis in MC3T3-E1 cells. The pine needle extract produced the highest level of collagen synthesis at concentrations of $10{\sim}50\;{\mu}g/ml$. These results indicate that pine needle extracts have an anabolic effect on bone by promoting osteoblastic differentiation, and may be used in the treatment of common metabolic bone diseases.

Assessment of Contamination and Geochemical Dispersion by Heavy Metals in Roadside Tree Leaves of Platanus occidentalis and Soils in the City of Seoul (서울시 가로수목 중 플라타너스 잎과 토양의 중금속 원소에 대한 지구화학적 분산과 오염평가)

  • Choo, Mi Kyung;Lee, Jin-Soo;Lee, Jeonghoon;Kim, Kyu-Han
    • Economic and Environmental Geology
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    • v.47 no.4
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    • pp.405-420
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    • 2014
  • To investigate geochemical characteristics of soil and atmospheric environments by anthropogenic source, we have analyzed and determined heavy metal concentrations of the surface soils beneath roadside trees and leaves of Platanus occidentalis from 52 points in Seoul during autumn 2001. For comparison of the contents of heavy metal for the soil and leaf, we have analyzed heavy metal contents of the surface soils beneath roadside trees and leaves from 2 points in rural area of Yesan during the same time period. The composition of heavy metals of soils are relatively high for Cd, Co, Cr and Ni in industrial area (IA, Industrial Area) and high for Cu, Pb and Zn in heavy traffic area (HTA, Heavy Traffic Area). The heavy metal contents of rural area in Seoul are higher than those in Yesan. The differences of chemical compositions between the washed and unwashed leaves are high for Cd, Cu, Pb and Zn in the HTA. The element couples of Cd-Co, Cr-Ni and Pb-Zn for the soils had shown a good correlation and their contamination sources could be similar. The relationship for Pb-Cu and Cu-Zn showed good correlation in Platanus leaves. The relationship between soils and unwashed leaves show a good correlation for Cr, Cu, Pb and Zn but low correlation for Cd, Co, Fe, Mn and Ni. It is thought that the Cr, Cu, Pb and Zn were derived from contaminants of soils, whereas Cd, Co, Fe, Mn and Ni were originated from atmospheric source. From the spatial variations of elements for soils and leaves, Ni and Cr were dominant in the soils of IA and Cd, Cu and Zn were dominant in those of HTA. The Contamination by Cd-Pb and Cu-Zn in unwashed leaves were analyzed to show similar patterns. Using the enrichment factors (EF) of heavy metals in unwashed leaves, the EF sequences were to be Cu, Zn, Pb, Mn, Co, Ni, Cd and Cr. We identified that Cu, Zn, Pb and Mn were most problematic of environmental hazard in Seoul.

Physico-Chemical Properties and Composition of Venison in Deer Breeds. (사슴 품종별 녹육의 이화학적 특성에 관한 연구)

  • 이길왕
    • Journal of Life Science
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    • v.14 no.3
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    • pp.525-530
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    • 2004
  • This study has been performed to examine physico-chemical properties and composition of venison in Deer breeds. According the results, moisture content in the venison ranged between 74% and 75%, and there were no significant differences among the breeds, or among the cutting parts. Fat content in the meats was estimated as less than 1% except in loin, protein contents was estimated as more than 22%, and ash content was estimated as more than 1.5%. For the contents of inorganic material in the loin, Fe$^{3+}$ content was higher in Elk than in other breeds, the contents of $Cu^{2+}$, $Mn^{2+}$, $K^{+}$, $Mg^{2+}$ and $Ca^{2+}$were higher in Red deer than in others, and the contents of $Fe^{3+}$, $K^{+}$, and $P^{+}$ were higher in Sika deer than in others. For the contents of inorganic material in the leg, the contents of $Cu^{2+}$, $Zn^{2+}$, $K^{+}$, $Ca^{2+}$ and $Mg^{2+}$ were higher in Elk than in other breeds, the contents of $Fe^{3+}$ and$P^{+}$ were higher in Red deer than in others, and the contents of $Cu^{2+}$ and $Fe^{3+}$were higher in Sika deer than in others. Amino acid contents in the venison alanine, proline, glycine, lycine and histidine were highly contained. and the contents of asparagine, cysteine, isoleucine and threonine were low. For the differences of amino acid contents among the breeds, the level was the higher in Sika deer than those of others. For the fatty acid in loin, the contents of myristic acid, oleic acid and linolenic acid in Sika deer were higher than those of others, the contents of myristic acid, palmitoleic acid, oleic acid and arachidonic acid in Red deer were higher than those of others and in Elk, the contents of palmitic acid and stearic acid were higher than those of others. For the contents of unsaturated fatty acid and polyunsaturated fatty acids, the level was higher in Red deer than those of others. For the fatty acid in leg, the contents of oleic acid, linolenic acid, linolenic acid and arachidonine acid in Sika deer were higher than those of others, the contents of myristic acid, palmitic acid, palmitoleic acid and oleic acid in Red deer were higher than those of others and in Elk, the contents of stearic acid and linolenic acid were higher than those of others. For the contents of saturated fatty acid, the level was lowest in Sika deer. For the contents of unsaturated fatty acid and polyunsaturated fatty acids were respectively highest in Sika deer. Comparing the contents inorganic materials between loin and leg, the concentrations in leg were generally higher than that of loin.n.

Heavy Metal Contamination around the Abandoned Au-Ag and Base Metal Mine Sites in Korea (국내 전형적 금은 및 비(base)금속 폐광산지역의 중금속 오염특성)

  • Chon Hyo-Taek;Ahn Joo Sung;Jung Myung Chae
    • Economic and Environmental Geology
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    • v.38 no.2 s.171
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    • pp.101-111
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    • 2005
  • The objectives of this study we to assess the extent and degree of environmental contamination and to draw general conclusions on the fate of toxic elements derived from mining activities in Korea. 인t abandoned mines with four base-metal mines and four Au-Ag mines were selected and the results of environmental surveys in those areas were discussed. In the base-metal mining areas, the Sambo Pb-Zn-barite, the Shinyemi Pb-Zn-Fe, the Geodo Cu-Fe and the Shiheung Cu-Pb-Zn mine, significant levels of Cd, Cu, Pb and Zn were found in mine dump soils developed over mine waste materials, tailings and slag. Furthermore, agricultural soils, stream sediments and stream water near the mines were severely contaminated by the metals mainly due to the continuing dispersion downstream and downslope from the sites, which was controlled by the feature of geography, prevailing wind directions and the distance from the mine. In e Au-Ag mining areas, the Kubong, the Samkwang, the Keumwang and the Kilkok mines, elevated levels of As, Cd, Cu, Pb and Zn were found in tailings and mine dump soils. These levels may have caused increased concentrations of those elements in stream sediments and waters due to direct dis-charge downstream from tailings and mine dumps. In the Au-Ag mines, As would be the most characteristic contaminant in the nearby environment. Arsenic and heavy metals were found to be mainly associated with sulfide gangue minerals, and mobility of these metals would be enhanced by the effect of oxidation. According to sequential extraction of metals in soils, most heavy metals were identified as non-residual chemical forms, and those are very susceptible to the change of ambient conditions of a nearby environment. As application of pollution index (PI), giving data on multi-element contamination in soils, over 1.0 value of the PI was found in soils sampled at and around the mining areas.

Study on the Geochemical Weathering Process of Sandstones and Mudstones in Pohang Basin at CO2 Storage Condition (지중저장 조건에서 초임계CO2에 의한 포항분지 사암과 이암의 지화학적 풍화반응 연구)

  • Park, Jinyoung;Lee, Minhee;Wang, Sookyun
    • Economic and Environmental Geology
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    • v.46 no.3
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    • pp.221-234
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    • 2013
  • Laboratory experiments for the reaction with supercritical $CO_2$ under the $CO_2$ sequestration condition were performed to investigate the mineralogical and geochemical weathering process of the sandstones and mudstones in the Pohang basin. To simulate the supercritical $CO_2$-rock-groundwater reaction, rock samples used in the experiment were pulverized and the high pressurized cell (200 ml of capacity) was filled with 100 ml of groundwater and 30 g of powdered rock samples. The void space of the high pressurized cell was saturated with the supercritical $CO_2$ and maintained at 100 bar and $50^{\circ}C$ for 60 days. The changes of mineralogical and geochemical properties of rocks were measured by using XRD (X-Ray Diffractometer) and BET (Brunauer-Emmett-Teller). Concentrations of dissolved cations in groundwater were also measured for 60 days of the supercritical $CO_2$-rock-groundwater reaction. Results of XRD analyses indicated that the proportion of plagioclase and K-feldspar in the sandstone decreased and the proportion of illite, pyrite and smectite increased during the reaction. In the case of mudstone, the proportion of illite and kaolinite and cabonate-fluorapatite increased during the reaction. Concentration of $Ca^{2+}$ and $Na^+$ dissolved in groundwater increased during the reaction, suggesting that calcite and feldspars of the sandstone and mudstone would be significantly dissolved when it contacts with supercritical $CO_2$ and groundwater at $CO_2$ sequestration sites in Pohang basin. The average specific surface area of sandstone and mudstone using BET analysis increased from $27.3m^2/g$ and $19.6m^2/g$ to $28.6m^2/g$ and $26.6m^2/g$, respectively, and the average size of micro scale void spaces for the sandstone and mudstone decreased over 60 days reaction, resulting in the increase of micro pore spaces of rocks by the dissolution. Results suggested that the injection of supercritical $CO_2$ in Pohang basin would affect the physical property change of rocks and also $CO_2$ storage capacity in Pohang basin.

Removal of Methyl tert-Butyl Ether (MTBE) by Modified Fenton Process for in-situ Remediation (Methyl tert-Butyl Ether(MTBE)의 in-situ Remediation을 위한 Modified Fenton Process에 관한 연구)

  • Chung, Young-Wook;Seo, Seung-Won;Kim, Min-Kyoung;Lee, Jong-Yeol;Kong, Sung-Ho
    • Journal of Soil and Groundwater Environment
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    • v.12 no.2
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    • pp.27-36
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    • 2007
  • A recent study showed that MTBE can be degraded by Fenton's Reagent (FR). The treatment of MTBE with FR, however, has a definite limitation of extremely low pH requirement (optimum pH $3{\sim}4$) that makes the process impracticable under neutral pH condition on which the ferrous ion precipitate forming salt with hydroxyl anion, which result in the diminishment of the Fenton reaction and incompatible with biological treatment. Consequently, this process using only FR is not suitable for in-situ remediation of MTBE. In order to overcome this limitation, modified Fenton process using NTA, oxalate, and acetate as chelating reagents was introduced into this study. Modified Fenton reaction, available at near neutral pH, has been researched for the purpose of obtaining high performance of oxidation efficiency with stabilized ferrous or ferric ion by chelating agent. In the MTBE degradation experiment with modified Fenton reaction, it was observed that this reaction was influenced by some factors such as concentrations of ferric ion, hydrogen peroxide, and each chelating agent and pH. Six potential chelators including oxalate, succinate, acetate, citrate, NTA, and EDTA were tested to identify an appropriate chelator. Among them, oxalate, acetate, and NTA were selected based on their remediation efficiency and biodegradability of each chelator. Using NTA, the best result was obtained, showing more than 99.9% of MTBE degradation after 30 min at pH 7; the initial concentration of hydrogen peroxide, NTA, and ferric ion were 1470 mM, 6 mM, and 2 mM, respectively. Under the same experimental condition, the removal of MTBE using oxalate and acetate were 91.3% and 75.8%, respectively. Optimum concentration of iron ion were 3 mM using oxalate which showed the greatest removal efficiency. In case of acetate, $[MTBE]_0$ decreased gradually when concentration of iron ion increased above 5 mM. In this research, it was showed that modified Fenton reaction is proper for in-situ remediation of MTBE with great efficiency and the application of chelatimg agents, such as NTA, was able to make the ferric ion stable even at near neutral pH. In consequence, the outcomes of this study clearly showed that the modified Fenton process successfully coped with the limitation of the low pH requirement. Furthermore, the introduction of low molecular weight organic acids makes the process more available since these compounds have distinguishable biodegradability and it may be able to use natural iron mineral as catalyst for in situ remediation, so as to produce hydroxyl radical without the additional injection of ferric ion.

EFFECT OF ENAMEL MATRIX DERIVATIVE (EMD, $EMDOGAIN^{(R)}$) ON THE DIFFERENTIATION OF CULTURED HUMAN PERIODONTAL LIGAMENT CELLS AND MESENCHYMAL STEM CELLS (배양된 사람 치주인대세포와 골수유래간엽줄기세포의 분화에 미치는 법랑기질유도체 (Enamel Matrix Derivative, EMD)의 영향)

  • Park, Sang-Gyu;Jue, Seong-Suk;Kwon, Yong-Dae;Choi, Byung-Joon;Kim, Young-Ran;Lee, Baek-Soo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.31 no.4
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    • pp.281-286
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    • 2009
  • Introduction: Enamel matrix derivative (EMD) is a protein which is secreted by Hertwig root sheath and plays a major role in the formation of cementum and attachment of peridontium. Several studies have shown that EMD promoted the proliferation and differentiation of preosteoblasts, osteoblasts and periodontal ligament cells in vitro: however, reports showing the inhibition of osteogenic differentiation by EMD also existed. This study was designed to simultaneously evaluate the effect of EMD on the two cell lines (human mesenchymal stem cells: hMSC, human periodontal ligament derived fibroblasts: hPDLCs) by means of quantitative analysis of some bone related matrices (Alkaline phosphatase : ALP, osteopontin ; OPN, osteocalcin ; OC). Materials and Methods: hMSCs and hPDLCs were expanded and cells in the 4${\sim}$6 passages were adopted to use. hMSc and hPDLCs were cultured during 1,2,7, and 14 days with 0, 50 and 100 ${\mu}g/ml$ of EMD, respectively. ALP activity was assessed by SensoLyte ALP kit and expressed as values of the relative optical density. Among the matrix proteins of the bony tissue, OC and OPN were assessed and quantification of these proteins was evaluated by means of human OC immunoassay kit and human OPN assay kit, respectively. Results: ALP activity maintained without EMD at $1,2^{nd}$ day. The activity increased at $7^{th}$ day but decreased at $14^{th}$ day. EMD increased the activity at $14^{th}$ day in the hPDLCs culture. In the hMSCs, rapid decrease was noted in $7^{th}$ and $14^{th}$ days without regard to EMD concentrations. Regarding the OPN synthesis in hPDLCs, marked decrease of OPN was noted after EMD application. Gradual decrease tendency of OPN was shown over time. In hMSCs, marked decrease of OPN was also noted after EMD application. Overall concentration of OPN was relatively consistent over time than that in hPDLCs. Regarding the OC synthesis, in both of hPDLCs and hMSCs, inhibition of OC formation was noted after EMD application in the early stages but EMD exerted minimal effect at the later stages. Conclusion: In this experimental condition, EMD seemed to play an inhibitory role during the differentiation of hMSCs and hPDLCs in the context of OC and OPN formation. In the periodontium, there are many kinds of cells contributing to the regeneration of oral tissue. EMD enhanced ALP activity in hPDLCs rather than in hMSCs and this may imply that EMD has a positive effect on the differentiation of cementoblasts compared with the effect on hMSCs. The result of our research was consistent with recent studies in which the authors showed the inhibitory effect of EMD in terms of the differentiation of mineral colony forming cells in vitro. This in vitro study may not stand for all the charateristics of EMD; thus, further studies involving many other bone matrices and cellular attachment will be necessary.