• 대한한방내과학회지
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• 제21권2호
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• pp.299-308
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• 2000

This study was performed to elucidate the effects of Gokajisilsosiho-Tang(GJST) on the lactic dehydrogenase(LDH) release, cell viability and activity, lipid peroxidation, DNA synthesis and the changes of total protein synthesis and GSH changes in vivo and in vitro in rat cultured hepatocytes from hydrogen peroxide$(H_2O_2)$-induced injury. The GJST extract had not an effect on cytotoxicity in all experimental results. The treatment of GJST extract of $160{\mu}g/ml$, $320{\mu}g/ml$ showed the significant effect to decrease LDH leakage induced by t-BHP in cultured rat hepatocytes. The higher concentration of GJST extract than $160{\mu}g/ml$, showed the inhibitory effect on decreasing cell viability induced by t-BHP. The treatment of t-BHP to rat cultured hepatocytes resulted in a concentration dependent increase in TBARS, in the presence of GJST extract the production of TBARS induced by hydrogen peroxide was inhibited concentration dependently, significantly inhibited at $80{\mu}g/ml$ of GJST extract and above. The GJST extract simutaneously present with t-BHP prevented the loss of total protein and GSH in a concentration dependent manner. These results suggested that GJST extract may play a hepatoprotective role in oxidative damage induced by hydrogen peroxide and a therapeutic potential of inhibiting liver injury.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.109-109
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• 1997

Inhibitory effect on DNA topoisomerase-I, rate of glutathione conjugation and cytotoxicity of naphthoquinone derivatives were correlated. During 5 min exposure of the derivatives to glutathione (GSH), it was found that 14% of 5,8-dimethoxy-1,4-naphthoquinone(DMNQ) was converted into a GSH-conjugate, whereas 5,8-dihydroxy-1,4-naphthoquinone(DHNQ) did not interact with GSH, implying that DMNQ exerted higher electrophilicity than DHNQ. However, DHNQ (IC$\_$50/, 0.15 ${\mu}$M) showed stronger cytotoxicity in L1210 cells than DMNQ(IC$\_$50/, 0.45 ${\mu}$M). The stronger cytotoxicity of DHNQ, compared to DMNQ, could be ascribed to more rapid redox cycling. Both naphthoquinones (IC$\_$50/, 60-65 ${\mu}$M) exhibiting about the same inhibitory effect on DNA topoisomerase-I were more potent than 1,4-naphthoquinone(1,4-NQ, IC$\_$50/, 134 ${\mu}$M). Thus, 5,8-oxy groups in the structure seem to be important for the inhibition of the enzyme. DMNQ showed a broader dose range while maintaining a good antitumor activity against S-180 fluid tumor. For these reasons, DMNQ was taken as useful pharmacophore for structural modification. Introduction of 1-hydroxyalkyl groups at C-2 of DMNQ lowered all of the activities mentioned above, while acetylation of 1-hydroxyalkyl moiety enhanced the activities by 4-5 times. Introduction of the same side chains at C-6 exhibited stronger activities than 2-substituted ones. Based on these results it was suggested that the quinonoid moiety in 6-substituted DMNQ was more exposed to cellular nucleophiles such as DNA, thiols of enzymes and so on. The synthesis of DHNQ or DMNQ derivatives are going on, and the corelationship between structure-activity will be discussed.

• 한국분말재료학회지
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• 제12권6호
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• pp.447-452
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• 2005

The synthesis and consolidation of titanium silicide by electro-discharge-sintering has been investigated. As-received Ti powder was in flaky shape and the mean particle size was $45.0{\mu}m$, whereas the mean particle size of the pre-milled Si powder with angular shape was $8.0{\mu}m$. Single pulse of 2.5 to 5.0 kJ/0.34g-elemental Ti and pre-milled Si powder mixture with the composition of $Ti-37.5at.\%$ Si was applied using $300{\mu}F$ capacitor. The solid with $Ti_5Si_3$ phase has been successfully fabricated by the discharge with the input energy more than 2.5kJ in less than $129{\mu}sec.$ Hv values were found to be higher than $1000kgf/mm^2$. The formation of $Ti_5Si_3$ occurred through a fast solid state diffusion reaction.

• 한국결정성장학회지
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• 제12권4호
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• pp.190-195
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• 2002

NaX seed결정(10~20 $\mu$m)을 $3.5Na_2$O : $Al_2O $: $2.1SiO_2$ : $1000H_2$O 용액에 0.5~2.0g 첨가한 후 연속결정화법으로 50 $\mu$m의 균일한 결정을 성장시켰다. 연속결정화법에 의한 결정성장을 시험하기 위하여, 모액을 7일, 5일, 3일, 2일과 1일 간격으로 공급하였다. Seed 첨가의 결과는 첨가하지 않은 용액과 비교하여 보다 균일하고 큰 결정들을 얻었다. 합성용액에 seed의 첨가는 반응물과 물리적인 접촉 면적을 초래하여 합성 겔의 핵성장 없이 seed 결정의 결정성장을 확인할 수 있다.

• KSBB Journal
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• 제25권1호
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• pp.18-24
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• 2010

본 연구에서는 가래나무 추출물의 항산화 효과와 티로시나제 활성 저해, 멜라닌 생성 및 티로시나제 합성 억제효과를 측정하고 이 추출물을 함유하는 제품의 임상시험을 실시하여 미백 화장품 소재로서의 개발 가능성을 관찰하였다. 가래나무 추출물은 농도 의존적으로 DPPH radical과 초산소 음이온 라디칼을 소거하였고, $SC_{50}$값은 각각 $20\;{\mu}g/mL$ 및 $25\;{\mu}g/mL$ 이었다. B16/BL6 멜라노마 세포를 이용하여 세포내 티로시나제 활성, 멜라닌 생성 및 티로시나제 합성 억제 효과를 측정한 결과 농도 의존적으로 티로시나제의 활성 및 멜라닌 생성을 억제하였으며, 티로시나제 단백질의 합성도 감소시켰다. 또한, 임상시험을 통하여 가래나무 추출물을 함유한 화장품이 대조 제품에 비해 통계적으로 유의한 피부 미백 효과가 있음을 확인하였다. 이상의 결과를 종합해 볼 때 가래나무 추출물은 색소침착 방지와 개선에 효과있는 새로운 미백 원료로 개발할 수 있을 것으로 사료된다.

• Journal of Plant Biology
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• 제35권1호
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• pp.37-43
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• 1992

A. rhizogenes A4 균주를 접종하여 청피홍심무우(Raphanus sativus cv. Chungpihongsim)의 모상근 배양을 확립하였다. 형질전환된 뿌리는 MS 배지의 기본염을 1/2로 희석하고, pH는 5.2, sucrose는 3%로 조정한 배양조건에서 최적성장을 보였다. 형질전환된 조직에서 합성되는 물질인 opine, 즉 agropine과 mannopine이 모상근의 추출액에서 검출되었다. 배지에 2, 4-D와 Kinetin이 첨가될 경우 모상근의 탈분화와 더불어 세포내에 안토시아닌의 합성이 유도되었으며, 그 중 2, 4-D $0.45\;\mu\textrm{M}$과 kinetin $2.3\;\mu\textrm{M}$의 첨가에서 최대의 색소 축적능을 보였다. 모상근의 탈분화와 함께 유도되는 안토시아닌의 paper chromatography 전개양상은 경작뿌리에서 추출한 색소에 비하여 다소 차이를 보였지만 모든 안토시아닌의 aglycone은 pelargonidin으로 확인되었다. 이러한 시료의 총 안토시아닌 함량은 0.49 mg/g(f.w.)로 계산되었다.

• 대한치과보철학회지
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• 제45권6호
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• pp.787-794
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• 2007

Statement of problem. Surface microgrooves on Ti substrata have been shown to alter the expression of genes responsible for various biological activities of cultured fibroblasts. However, their effect on enhancing cell proliferation is not yet clear. Purpose. The purpose of this study was to determine the dimension of surface microgrooves on Ti substrata that enhances proliferation and alters gene expression of cultured human gingival fibroblasts. Material and methods. Commercially pure Ti discs with surface microgrooves of monotonous $3.5{\mu}m$ in depth and respective 15 and $30{\mu}m$ in width were fabricated using photolithography and used as the culture substrata in the two experimental groups in this study (TiD15 and TiD30), whereas the smooth Ti was used as the control substrata (smooth Ti group). Human gingival fibroblasts were cultured on the three groups of titanium substrata and the proliferation, DNA synthesis, and gene expression of theses cells were analyzed and compared between all groups using XTT assay, BrdU assay, and reverse transcriptase-polymerase chain reaction (RT-PCR), respectively. Results. From the XTT assay at 48 h incubation, the proliferation of human gingival fibroblasts in TiD30 was significantly enhanced compared to that in smooth Ti and TiD15. The results from the BrdU assay showed that, at 24 h incubation, the DNA synthesis was significantly enhanced in TiD30 compared to that in smooth Ti. In RT-PCR, increase in the expression of PCR transcripts of fibronectin, CDK6, $p21^{cip1}$ genes was noted at 48h incubation. Conclusion. Surface microgrooves $30{\mu}m$ in width and $3.5{\mu}m$ in depth on Ti substrata enhance proliferation and alter gene expression of cultured human gingival fibroblasts.

• 약학회지
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• 제43권6호
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• pp.809-817
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• 1999

The effect of 2-(4-cyanophenyl)amino-1,4-naphthalenedione-3-pyridinium perchlorate (PQ5) on pla-telet aggregation and its action mechanisms were investigated with rat platelet. PQ5 inhibited the platelet aggregation induced by collagen ($6{\;}{\mu\textrm{g}}/ml$), thrombin (0.4 U/ml) and A23187 ($3{\mu}M$) in concentration-dependent manner with $IC_{50}$ values of 5.50, 25.89 and $37.12{\;}{\mu}M$, respectively. PQ5 also significantly reduced the thromboxane $A_2$ (TXA2) formation in a concentration dependent manner. The collagen-induced arachidonic acid (AA) release in [-3H]-AA incorporated platelet, an indication of the phospholipase $A_2$ activity, was decreased by PQ5 pretreatment PQ5 significantly inhibited the activity of thormboxane synthase only at high concentration ($100{\mu}M$), but did not affect the cyclooxygenase activity at all. Collagen-induced ATP release was significantly reduced by PQ5. Calcium-induced platelet aggregation experiment suggests that the elevation of intracellular free $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) by collagen stimulation is decreased by the pretreatment of PQ5, which is due to the inhibition of calcium release from intracellular store and influx from outside of the cell. PQ5 did not showed the effect of anticoagulation as prothrombin time (PT) or activated partial thromboplastin time (APTT). Form these results, it is suggested that PQ5 exerts its antiplatelet activity through the inhibition of the intracellular $Ca^{2+}$ mobilization and the decrease of the $TXA_2$ synthesis.

• Biomolecules & Therapeutics
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• 제7권3호
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• pp.227-233
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• 1999

The effects of 2-bromo-3-(3,5-tert-butyl-4-hydroxylphenyl)-1,4-naphthalenedione(TPN2), a synthetic vitamin K derivative, on platelet aggregation and its action mechanisms were investigated in rat platelet. TPN2 inhibited the platelet aggregation induced by collagen($10\mu\textrm{g}$/ml), thrombin(0.1 U/ml), A23187($10\mu\textrm{M}$) and arachidonic acid($100\mu\textrm{M}$) in concentration-dependent manner with $IC_{50}$ values of 6.5$\pm$1.3, 59.3$\pm$4.5, 13.0$\pm$2.37 and 2.9$\pm$$1.0\mu\textrm{M}$, respectively. Collagen-induced serotonin release was significantly reduced by TPN2. The elevation of intracellular free $Ca^{2+}$ concentration ([$Ca^{2+}$]i) by collagen stimulation was greatly decreased by the pretreatment of TPN2, which was due to the inhibition of calcium release from intracellular store and influx from outside of the cell. TPN2 also significantly reduced the thromboxane $A_2$($TXA_2$) formation in a concentration-dependent manner. The collagen-induced arachidonic acid (AA) release in [$^3H$]-AA incorporated platelet, an indicative of the phospholipase $A_2$ activity, was decreased by TPN2 pretreatment. TPN2 significantly inhibited the activity of thromboxane synthase, but did not affect the cyclooxygenase activity. From these results. it is suggested that TPN2 exert its antiplatelet activity through the inhibition of the intra-cellular $Ca^{2+}$ mobilization and the decrease of the $TXA_2$ synthesis.

• 한국식품영양과학회지
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• 제33권4호
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• pp.646-652
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• 2004

CCD 1108Sk를 이용한 세포 활성을 조사한 결과 Sigma사 제품(Bovine Trachea에서 얻어진 콘드로이틴황산)은 80 $\mu\textrm{g}$/mL에서 높은 활성을 보였으나, 미더덕 및 멍게로부터 추출한 콘드로이틴황산은 400∼600 $\mu\textrm{g}$/mL에서 높은 활성을 보였다. 이러한 활성의 차이는 순도의 차이에 기인하거나 서로 다른 구조에 기인한다고 여겨졌다. 그러나 MDD F2은 1,000 $\mu\textrm{g}$/mL에서 활성이 증가하는 모습이 보였지만 MDD F2는 미약하게 증가하는 모습을 보여 fraction들간에 차이가 있음을 보였다. A 431 주화세포를 이용한 실험에서는 Sigma사 제품과 미더덕과 멍게에서 추출한 crude 콘드로이틴황산의 경우는 CCD 1108Sk에서 보여준 결과와 비슷하였으나, MDD F1과 F2는 모두 600∼1,000 $\mu\textrm{g}$/mL 사이에서 최고의 활성을 보였다. Collagen 한성에 있어서는 bovine trachea, MDD F1과 F2는 조사 범위에서는 특이 활성을 보이지 않았다. 그러나 멍게에서 추출한 콘드로이틴황산의 경우는 100 $\mu\textrm{g}$/mL에서, 미더덕에서 추출한 콘드로이틴황산의 경우는 50 $\mu\textrm{g}$/mL 에서 CCD 1108Sk세포에서 각각 최고의 활성을 보였다. 그러나, A 431세포에서는 검사한 모든 물질에 대하여 특이 반응을 확인할 수 없었다. 자외선 손상에 대한 회복능 조사는 세포 상층액과 세포 자체가 생성한 LDH를 조사한 결과, 멍게와 미더덕에서 추출한 콘드로이틴황산의 경우는 400 $\mu\textrm{g}$/mL에서 CCD 1108Sk 세포의 상층액에서 높은 LDH를 보였으나, 다른 물질의 경우 조사범위에서는 반응을 보이지 않았고, 세포 자체에서도 LDH는 조사 물질간 큰 차이를 나타내지는 않았다. 멍게와 미더덕에서 추출한 crude 콘드로이틴황산의 경우는 400 $\mu\textrm{g}$/mL에서 최고의 활성을 보였다. 전체적으로 멍게에서 추출한 콘드로이틴황산이 미더덕에서 추출한 콘드로이틴황산의 경우보다 세포활성이 높게 나타났다. 그렇지만 두 해양생물로부터 추출한 콘드로이틴황산은 화장품 원료로서의 사용이 가능함이 판명되었다.