• Journal of Periodontal and Implant Science
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• 제34권1호
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• pp.49-59
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• 2004

The goal of periodontal treatment is not only to arrest the progression of the disease but also to promote the functional, esthetic regeneration of the periodontium. Flap operation, bone graft, guided tissue regeneration, growth factors and bone morphogenetic protein have been used for this purpose. Among these techniques of regeneration, alloplastic graft, especially calcium phosphate is getting more attention recently. The purpose of this study was to evaluate the effects of calcium phosphate glass on mouse calvarial cell in vitro. The toxicity of calcium phosphate glass was measured using MTT assay, the synthesis of collagen was measured using collagen assay, and ALP activity was measured. The experimental groups were cultured with calcium phosphate glass(both AQ-, and HT-CPG) in concentration of 0.01, 0.02, 0.1, 0.2g/ml. The results are as follows 1. In concentrations not exceeding 0.02g/ml, both the groups(AQ-CPG, HT-CPG) didn't show any toxicity on mouse calvarial cell(p<0.05). 2. In both the experimental groups are the concentration of 0.02g/ml, collagen expressions were significantly up-regulated (p<0.05). 3. In both the experimental groups are the concentration of 0.02g/ml, ALP activity was not significantly up-regulated, but ALP activity in both experimental groups were greater than control group(p<0.05). The results suggested that the use of calcium phosphate glass may promotes periodontal regeneration. Ongoing studies are necessary in order to determine their regeneration effects.

• Journal of Nutrition and Health
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• 제29권5호
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• pp.461-471
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• 1996

This study was performed to investigate the effect of dietary protein and cysteine levels on cadmium toxicity in rats. Seventy-two male rats of Sprague-Dawley strain weighting 171$\pm$3g were blocked into 12 groups according to body weight, and were raised for 30 days. cadmium chloride was given at levels of 0 or 400ppm, protein at levels of 7, 15 and 40%, and cysteine was added(total dietary cysteine contents : 0.45%) to diet or not. The results are summarized as follow. Food intake, weight gain, food were lower than those of cadmium free group. But, these were increased with increasing dietary protein level and cysteine addition. Fecal cadmium excretion was remarkably increased in high protein (40%) groups. Thus, cadmium retention rates were decreased in high protein groups. Metallothionein concentrations in liver and kidney were increased in cysteine addition, and cadmium administration. Especially, these were remarkably increased in cadmium and cysteine added groups. Urinary calcium excretion was increased with cadmium administration, but urinary protein excretion and creatinine clearance were not changed in these animal. In conclusion, food intake, weight gain and organ weights were decreased with administration. Cadmium toxicity was alleviated by increasing fecal cadmium excretion, while cysteine addition increased metallothionein concentrations in liver and kidney. From these results, it was shown that cadmium toxicity was alliviated by synergistic effect of high protein level and cysteine addition.

• 대한약리학회지
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• 제32권2호
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• pp.211-219
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• 1996

The inhibitory effect of cyclosporin A (CsA) on nitric oxide production is not related to the immunosuppressive action of the drug, but to the renal toxicity and arterial hyper-tension. In this study the experimental interventions to reverse the inhibition of nitric oxide production by cyclosporin A in rat aortic smooth muscle cells were examined. CsA inhibited the accumulation of nitrite, the stable end product of nitric oxide, in culture media in a concentration $(0.1{\sim}100{\mu}g/ml)-dependent$ manner. The inhibitory effect of CsA on nitrite accumulation were not antagonized by arginine (10 mM), a substrate of nitric oxide synthase, nor by calcium ionophore A23187 $(7{\mu}M)$. Forskolin, an activator of adenylate cyclase, which enhanced iNOS induction at transcriptional level, completely reversed the inhibitory action of CsA on nitrite accumulation. However, PMA (2 nM) and PDB (50 nM), PKC activators, increased the inhibitory action of CsA on nitrite accumulalion. From these results, it is suggested that cyclic AMP-elevating agents may be candidates of therapeutic agents in prevention and treatment of renal toxicity and arterial hypertension induced by CsA. Among conventional antihypertensive drugs, calcium channel blockers and ${\alpha}-blockers$ are preferred to ${\beta}-blockers$.

• Environmental Analysis Health and Toxicology
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• 제28권
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• pp.2.1-2.7
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• 2013

Objectives Tricalcium phosphate and calcium hydrogenorthophosphate are high production volume chemicals, mainly used as foodstuff additives, pharmaceuticals, lubricants, synthetic resin, and disinfectants. Phosphate has the potential to cause increased algal growth leading to eutrophication in the aquatic environment. However, there is no adequate information available on risk assessment or acute and chronic toxicity. The aim of this research is to evaluate the toxic potential of phosphate compounds in the aquatic environment. Methods An aquatic toxicity test of phosphate was conducted, and its physico-chemical properties were obtained from a database recommended in the Organization for Economic Cooperation and Development (OECD) guidance manual. An ecotoxicity test using fish, Daphnia, and algae was conducted by the good laboratory practice facility according to the OECD TG guidelines for testing of chemicals, to secure reliable data. Results The results of the ecotoxicity tests of tricalcium phosphate and calcium hydrogenorthophosphate are as follows: In an acute toxicity test with Oryzias latipes, 96 hr 50% lethal concentration ($LC_{50}$) was >100 (measured:>2.14) mg/L and >100 (measured: >13.5) mg/L, respectively. In the Daphnia test, 48 hr 50% effective concentration ($EC_{50}$) was >100 (measured: >5.35) mg/L and >100 (measured: >2.9) mg/L, respectively. In a growth inhibition test with Pseudokirchneriella subcapitata, 72 hr $EC_{50}$ was >100 (measured: >1.56) mg/L and >100 (measured: >4.4) mg/L, respectively. Conclusions Based on the results of the ecotoxicity test of phosphate using fish, Daphnia, and algae, $L(E)C_{50}$ was above 100 mg/L (nominal), indicating no toxicity. In general, the total phosphorus concentration including phosphate in rivers and lakes reaches levels of several ppm, suggesting that phosphate has no toxic effects. However, excessive inflow of phosphate into aquatic ecosystems has the potential to cause eutrophication due to algal growth.

• Bulletin of the Korean Chemical Society
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• 제34권2호
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• pp.482-488
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• 2013

Two piperazine-containing 3,4-dihyroquinazolines (BK10007S/8S) have been synthesized, based on our previous work on the synthesis and antitumoral activity of 3,4-dihyroquinazolines. After evaluating them for T-type calcium channel blocking effect and in vitro anti-cancer effect, they were profiled for acute and repeat dose toxicity (40 mg/kg, 2 weeks) to BALB/c mice. BK10007S/8S were further in vivo evaluated against human pancreatic MIA PaCa-2 carcinoma in $BALB/c^{nu/nu}$ nude mice, which exhibited 54 and 61% tumor growth inhibition through 57-day oral administration of 2 mg/kg of body weight, respectively.

• Biomolecules & Therapeutics
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• 제19권2호
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• pp.181-186
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• 2011

Beta-amyloid (A${\beta}$) is considered as one of the major causes of Alzheimer's disease. This study examined the neuroprotective effects of chlorogenic acid, a naturally occurring polyphenol which is distributed widely in plants, fruits and vegetables, against A${\beta}$-induced toxicity. A${\beta}$ decreased significantly the viability of PC12 cells. This was accompanied by an increase in the intracellular calcium levels and cleaved caspase-3. In addition, A${\beta}$ induced an increase in Bax, and a decrease in Bcl-2 compared to the controls. However, a pre-treatment with chlorogenic acid rescued the PC12 cells from A${\beta}$ by attenuating the elevated intracellular calcium levels and reducing the levels of the apoptosis related proteins, including caspase-3, Bcl-2 and Bax. These results suggest that the protective effects of chlorogenic acid are, at least in parts, by attenuating the intracellular calcium influx and reducing apoptosis induced by A${\beta}$.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제10권S_2호
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• pp.89-95
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• 2001

The solidification and leaching characteristics of cyclone ash collected from an industrial incineration plant were investigated. Cement and calcium hydroxide were used as the solidifying materials. The leaching characteristics of the solidified cyclone ash were found to vary depending on both the quantitative and the qualitative aspects of the solidifying materials. Except for copper and lead, all the heavy metal ions in the leachate of the solidified material composed of 10~20 % cement or 10~20 % calcium hydroxide were found to be within their standard limit. Moreover, all the heavy metal ions were also observed to be within satisfactory limits in the leachate obtained from the solidified material composed of 30 % cement or 30 % calcium hydroxide. Therefore, to satisfy the standard compressive intensity and permissible limits of heavy metal ions leached from solidified material, it would appear that a 30 % proportion of either additive in the solidification product can meet the required standard for the leachate. The cost of solidifying cyclone ash per ton for ash-30 % cement and ash-30 % lime was calculated as 26,750 and 26,070 won, respectively. Accordingly, significant reduction in the waste toxicity and mobility as well as an improvement in the engineering properties of the solidified products were successfully achieved.

• 한국발생생물학회지:발생과생식
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• 제3권1호
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• pp.45-51
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• 1999

소 배반포로부터 배아주 (embryonic stem, ES) 유사세포를 분리하기 위해서는 영양외배엽 (trophectoderm, TE) 세포를 제거하는 것이 효과적이다. 따라서 본 실험은 효과적으로 TE를 제거하기 위한 calcium ionophore A23187 (CIPA) 처리조건을 확립하고, 분리해낸 ES 유사세포의 in vitro 다능성 (pluripotency)을 검증하고자 수행하였다. CIPA 농도 및 처리시간을 달리 하였을 때 50 $\mu$M에서 25분간 처리한 군이 colony 형성율 (51%)및 10 passage 까지의 배양성적 (4.8%)에서 가장 좋은 결과를 나타내었다. 또한 CIPA를 처리하지 않은 군과의 비교에서도 약 5배의 높은 결과를 보임으로서 본 실험에서 확립된 CIPA 처리조건은 가시적인 toxicity 없이 ES 유사세포의 확립에 이용될 수 있음을 시사하였다. 확립된 ES 유사세포는 heterogeneous한 alkaline phosphatase (AP) 활성을 보여 소 ES 유사세포에 대한 타 보고들과 유사한 결과를 보였다. In vitro 부양배양 (suspension culture)에서는 embryoid body로 분화가 가능하였으며, 약 70% 정도의 euploidism을 보였다. 따라서 본 실험에서 확립된 CIPA의 처리조건이 소 배반포로부터 ES 유사세포를 확립하는데 효과적으로 이용될 수 있음을 확인할 수 있었다.

• Biomolecules & Therapeutics
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• 제26권5호
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• pp.439-445
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• 2018

T-type calcium channels are low voltage-activated calcium channels that evoke small and transient calcium currents. Recently, T-type calcium channels have been implicated in neurodevelopmental disorders such as autism spectrum disorder and neural tube defects. However, their function during embryonic development is largely unknown. Here, we investigated the function and expression of T-type calcium channels in embryonic neural progenitor cells (NPCs). First, we compared the expression of T-type calcium channel subtypes (CaV3.1, 3.2, and 3.3) in NPCs and differentiated neural cells (neurons and astrocytes). We detected all subtypes in neurons but not in astrocytes. In NPCs, CaV3.1 was the dominant subtype, whereas CaV3.2 was weakly expressed, and CaV3.3 was not detected. Next, we determined CaV3.1 expression levels in the cortex during early brain development. Expression levels of CaV3.1 in the embryonic period were transiently decreased during the perinatal period and increased at postnatal day 11. We then pharmacologically blocked T-type calcium channels to determine the effects in neuronal cells. The blockade of T-type calcium channels reduced cell viability, and induced apoptotic cell death in NPCs but not in differentiated astrocytes. Furthermore, blocking T-type calcium channels rapidly reduced AKT-phosphorylation (Ser473) and $GSK3{\beta}$-phosphorylation (Ser9). Our results suggest that T-type calcium channels play essential roles in maintaining NPC viability, and T-type calcium channel blockers are toxic to embryonic neural cells, and may potentially be responsible for neurodevelopmental disorders.

• 대한치과교정학회지
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• 제32권2호통권91호
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• pp.129-142
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• 2002

사회적, 경제적 여건의 향상으로 성인들의 교정치료에 대한 관심이 커지고 있지만 폐경기 여성에 있어서 골다공증의 증가는 교정치료에 제한이 되며, 골다공증과 카페인과의 관련 여부는 최근까지 논란이 되고 있다. 따라서 본 연구의 목적은 생후 1일된 마우스의 골모세포를 in Vitro상에서 카페인과 칼슘 및 이 둘을 혼합 처리하여 골모세포의 활성에 미치는 영향에 대해 알아보고자 하였다. 실험에 사용한 골모세포는 마우스의 두개관에서 얻었으며, 카페인 단독 처리, 칼슘 단독 처리, 카페인과 칼슘의 혼합처리를 시행하였다. 카페인 처리를 한 경우 1일, 2일, 4일째 세포 독성 정도를 570 nm ELISA로 분석을 시행하였고, 카페인, 칼슘 및 혼합 처리시 배양 후 28일째 Von Kossa staining 후 영상분석기에 의해 광화된 골결절의 밀도를 측정하였으며, 염기성 인산분해효소 활성도 변화를 배양 후 2일, 7일, 14일, 21일, 28일째 405 nm spectrophotometer로 측정하였고, IL-1 ${\beta}$의 활성도를 48시간 후 492 nm ELISA로 분석을 시행하였다. 얻어진 수치들은 ANOVA test로 통계 분석하였다. 1. 카페인에 대한 세포 독성은 카페인의 농도가 1.0 mM, 2.0 mM로 증가함에 따라, 2일, 4일로 배양 기간이 길어짐에 따라 유의하게 증가하였고, 세포수는 감소하였다. 2. 광화된 골결절의 밀도는 카페인을 단독 처리한 경 우 0.2 mM에서, 칼슘 단독 처리시에는 1.2 mM에서, 혼합 처리한 경우 0.1 mM 카페인과 1.8 mM 칼슘에서 가장 크게 나타났다. 3. 염기성 인산분해효소 활성도는 비처리시 칼슘과 같이 14일째 최대값을 보이는 반면, 카페인을 단독 처리한 경우 농도가 증가함에 따라 활성도가 증가하였다. 카페인과 칼슘 혼합 처리시에는 칼슘 농도가 1.2 mM, 1.8 mM인 경우 배양 14일에 염기성 인산분해효소의 활성도가 유의하게 증가하였으나, 2.5 mM인 경우 활성도가 감소하였다. 4. II-1 ${\beta}$의 활성도는 카페인을 단독 처리한 경우 0.2 mM, 1.0 mM에서, 칼슘 단독 처리시에는 1.8 mM에서, 혼합 처리시 0.1 mM 카페인과 1.8 mM 칼슘 혼합 처리한 경우 높게 나타났고, 고농도의 카페인, 칼슘 혼합 처리 시에는 낮게 나타났다 이러한 실험 결과를 통하여 칼슘이 1.2 mM, 1.8 mM 농도로 존재하는 경우 카페인에 의한 골모세포의 염기성 인산분해효소 활성과 IL-1 ${\beta}$의 활성 억제 효과가 어느 정도 회복되나, 2.5 mM 고농도의 칼슘은 억제된 활성을 회복시키지 못함을 확인하였다.