• 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.

• Restorative Dentistry and Endodontics
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• 제27권6호
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• pp.632-643
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• 2002

The purpose of this study was two-fold. First was to evaluate whether the molecular sieving model was appropriate for ionic dissociation experiment. Second was to compare the dissociation of calcium and hydroxyl ions from five types of calcium hydroxide pastes (Pure calcium hydroxide paste, DT temporary $dressing^{\circledR},{\;}Metapaste^{\circledR},{\;}Chidopex^{\circledR},{\;}Metapex^{\circledR}$) in three vehicles (aqueous, viscous and oily) and the antibacterial effect. Each calcium hydroxide pastes was placed into 0.65ml tube with cap and then 15% polyacrylamide gel was placed onto calcium hydroxide pastes. After the gel was hardened, the tubes were filled with tridistilled water (pH 7.14) and closed with cap. The tubes were stored in $37^{\circ}C$ 100% incubator The pH reading and the concentration of calcium ions were taken at 1, 4, 7. 10, and 14 days. The brain heart infusion agar plates with S. mutans and A. actinomycetemcomitans were used far antibacterial activity test. Middle of agar plate was filled with the calcium hydroxide pastes. The plates were incubated at $37^{\circ}C$ and observations were made to detect the zones of inhibition. These data were evaluated statistically by use of the analysis of variance and duncan test. The results were as follows. 1. In fresh mixing state, the pH of five types of calcium hydroxide pastes were measured between 12.5 and 12.8. 2. The pH was increased in all five types of calcium hydroxide pastes compared with control group. In 14 days, Pure calcium hydroxide paste (11.45) and DT temporary $dressing^{\circledR}$ (11.33) showed highest pH, followed by $Metapaste^{\circledR}$ (9.49), $Chidopex^{\circledR}$ (8.37) and $Metapex^{\circledR}$ (7.59) 3. Calcium was higher in all five types of calcium hydroxide pastes compared with control group. In 14 days, Pure calcium hydroxide paste (137.29 mg%) and DT temporary $dressing^{\circledR}$ (124.6 mg%) showed highest value, followed by $Metapaste^{\circledR}$ (116.74 mg%), $Chidopex^{\circledR}$ (111.84 mg%) and $Metapex^{\circledR}$ (60.22 mg%). 4. The zones of bacterial inhibition were seen around all five types of calcium hydroxide pastes. $Chidopex^{\circledR}{\;}and{\;}Metapex^{\circledR}$ groups which include iodoform were observed significantly larger zone of inhibition in A. actinomycetemcomitans compared with the other calcium hydroxide groups (p<0.05) However, $Metapex^{\circledR}$ showed the least antibacterial effect on S. mutans compared with other groups (p<0.05). The molecular sieving model was found to be acceptable in dissociation experiment of hydroxyl and calcium ions when compared with the previous tooth model study. But this model was not appropriate for the antibacterial test.

• 한국환경농학회지
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• 제14권1호
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• pp.55-71
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• 1995

소맥 종자의 발아 과정중 strontium의 생리적 작용을 규명하기 위해 초엽, 종근 및 배유에서의 free amine의 함량변화가 측정되었다. $GA_3$를 포함한 배양액에 strontium 농도의 증가는 종근에서의 putrescine과 초엽에서의 spermidine의 축적을 현저히 유발하였다. $10\;{\mu}M$ 정도의 저농도에서도 strontium에 의한 putrescine 증가는 뚜렷한 반면, spermidine 증가는 10 mM의 고농도 처리에서 현저했다. 종근 생장을 억제하는 1mM 내지 10mM의 strontium 농도에서, g 생체중당 putrescine 수준은 동일농도 calcium 처리에서 보다 각각 22.4배와 15.3배 높았다. 특히 putrescine과 spermidine 증가에 의한 총 free amine 수준의 중가는 생체중 대비 뿐만이 아닌 RNA 함량 대비에서도 중요한 생리적 반응으로 보여졌다. Strontium과 대조적으로 고농도 calcium (10 mM) 처리는 초엽과 종근에서의 agmatine과 cadaverine 함량의 증가를 유발했다. Cadaverine은 calcium을 처리했을 경우에만 검출되었다. 그러나 $1\;{\mu}M$ 에서 1 mM 수준의 calcium 처리는 총 free amine 함량의 감소를 가져왔다. Strontium과 calcium 존재하에서의 발아과정중 축적되는 amine 종류의 차이와 총 free amine 중 diaminine 비율과 총 free amine 중 Polyamine 비율의 변화는 strontium과 calcium 간의 생리적 대사반응의 차이중 하나로 판단되었다.

• 대한소아치과학회지
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• 제25권2호
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• pp.335-351
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• 1998

Salivary proteins which are produced in the saliary acinar cells have been known to be involved in the Calcium and phosphate metabolism. The acquired pellicle resulting from such metabolism is considered as a secondary defence membrane against tooth caries. In this respect, some proteins included in saliva probably play an important role in the prevention of demineralization in enamel. On the other hand, fluoride has long been known to prevent the demineralization of enamel by the inhibition of the growth of Streptococcus mutans(S. mutans) and by the chemical reaction with calcium and phosphate, Therefore, I have examined the roles of amylase and albumin in the demineralization of enamel and compared these preteins with fluoride in terms of anticariogenic effect. 1. The demineralization caused by S. mutans occurred slowly and progressively for the first 60 min, then the rate of demineralization was accelerated afterwards. 2. pH decreased continuously during the entire period of each experiment. 3. The demineralization was significantly inhibited by the preteatment of amylase and fluoride but albumin had little effect on it. 4. An addition of 0.1 mM lactic acid (final concentration 0.1 ${\mu}M$) caused a rapid increase in calcium concentration reaching a maximum within 10 min. 5. pH decreased rapidly by the addition of 0.1 mM lactic acid and reached a minimum within a few seconds followed by an increase in pH. pH reaced a plateu with 10 min. 6. Fluoride, amylase and albumin played little role in the 0.1 mM lactic acid-induced demineralization. 7. A slow infusion of 0.1 M lactic acid at a rate of 5 ${\mu}l/min$ caused a slower increase in calcium concentration compared with the bolus addition of lactic acid. 8. Fluoride had an inhibitory effect on the calcium release caused by slow infusion of lactic acid while amylase and albumin had no effect on it. These results suggest that fluoride inhibits demineralization by protecting the HA from the acid attack whereas amylase has a direct effect on S. mutans to prevent demineralization.

• Korean Chemical Engineering Research
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• 제52권5호
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• pp.620-626
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• 2014

The main focus of this study was the evaluation of arsenic concentration in the ground water of Lahore at different depth and application of different mitigation techniques for arsenic removal. Twenty four hours of solar oxidation gives 90% of arsenic removal as compared to 8 hr. or 16 hr. Among oxides, calcium oxide gives 96% of As removal as compared to 93% by lanthanum oxide. Arsenic removal efficiency was up to 97% by ferric chloride, whereas 95% by alum. Activated alumina showed 99% removal as compared to 97% and 95% removal with bauxite and charcoal, respectively. Elemental analysis of adsorbents showed that the presence of phosphate and silica can cause a reduction of arsenic removal efficiency by activated alumina, bauxite and charcoal. This study has laid a foundation for further research on arsenic in the city of Lahore and has also provided suitable techniques for arsenic removal.

• 펄프종이기술
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• 제32권3호
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• pp.65-74
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• 2000

This study was carried out to acquire basic data necessary for the use of rice-straw chemical pulp. It investigated the proper bleaching conditions when rice-straw chemical pulps(alkaline sulfite-Na2S2O4 pulp) were bleached with the various kinds of bleaching agents. And physical properties of bleached pulps were tested. The results of this study were as follows; 1, The proper conditions of chlorine sequence were determined to be 4% concentration of chlorine 25$^{\circ}C$ of reaction temperature and 50 minutes of reaction time. 2. For calcium hypochlorite sequence the proper conditions of chemical concentration reac-tion temperature and reaction time were 3% 25$^{\circ}C$ and 20 minutes respectively. 3. For chlorine dioxide sequence the proper conditions were 1% concentration of chlorine dioxide 70$^{\circ}C$ of reaction temperature and 2hr. of reaction time. 4. The proper conditions of hydrogen peroxide sequence were 1.5% concentration of hydro-gen peroxide 70$^{\circ}C$ of reaction temperature and 1hr. of reaction time respectively. 5. When the rice-straw chemical pulp were bleached with four kinds of bleaching agents methioned above in the proper conditions respectively brightnesses were the order of chlorine dioxide calcium hypochlorite, chlorine, hydrogen peroxide. And strengthes of pulps bleached with chlorine dioxide and hydrogen peroxide were higher than those of pulps bleached with other bleaching agents.

• 한국식품저장유통학회지
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• 제22권2호
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• pp.297-302
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• 2015

저활용 단백질로부터 칼슘 결합물질을 분리하기 위해 돼지 육골분과 진주담치 단백질을 단백질 분해 효소인 alcalase를 이용하여 가수분해물을 제조하였고, 체내 흡수가 용이한 3 kDa 이하로 한외여과 하였다. 돼지 육골분 가수분해물은 Mono Q 컬럼을 통해 분리하였고, 진주담치 가수분해물의 경우 Q-Sepharose로 분리 하여 각각 2개, 3개의 peptide fraction을 얻어 각 fraction의 칼슘 결합력을 측정하였다. 그 결과 MBM F2와 Mussel F3에서 가장 높은 칼슘 결합력을 나타내었고, 따라서 본 연구 결과로 얻어진 가수분해물들은 칼슘 보충 소재로 활용될 수 있다고 판단된다.

• Journal of Korean Neurosurgical Society
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• 제45권4호
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• pp.231-235
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• 2009

Objective : While many factors contribute to aging, changes in calcium homeostasis and calcium related neuronal processes are likely to be important. High intracellular calcium is toxic to cells and alterations in calcium homeostasis are associated with changes in calcium-binding proteins, which confine free $Ca^{2+}$. We therefore assayed the expression of the calcium binding proteins calretinin and calbindin in the central auditory nervous system of rats. Methods : Using antibodies to calretinin and calbindin, we assayed their expression in the cochlear nucleus, superior olivary nucleus, inferior colliculus, medial geniculate body and auditory cortex of young (4 months old) and aged (24 months old) rats. Results : Calretinin and calbindin staining intensity in neurons of the cochlear nucleus was significantly higher in aged than in young rats (p<0.05) The number and staining intensity of calretinin-positive neurons in the inferior colliculus, and of calbindin-positive neurons in the superior olivary nucleus were greater in aged than in young rats (p<0.05). Conclusion : These results suggest that auditory processing is altered during aging, which may be due to increased intracellular $Ca^{2+}$ concentration, consequently leading to increased immunoreactivity toward calcium-binding proteins.

• Archives of Pharmacal Research
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• 제21권6호
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• pp.774-778
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• 1998

Brazilin [7,11b-dihydrobenz[b]indeno[1,2-d]pyran-3,6a,9,10(6H)-tetrol] inhibited thrombin-, collagen- and ADP-induced aggregation of washed rat platelets. T hrombin- and collagen-induced ATP release were also inhibited by brazilin in a concentration-dependent manner. Brazilin inhibited the formation of platelet thromboxane $A_2$ caused by thrombin, whereas it had no effect on the prostaglandin $D_2$ formation. Brazilin inhibited $^3H$-arachidonic acid liberation from membrane phospholipids of thrombin-stimulated platelets. Brazilin inhibited the rise of intracellular free calcium caused by thrombin. These results indicate that the inhibition of phospholipase ($PLA_2$) activity and [$[Ca^{2+}]_1$ elevation might be at least a part of antiplatelet mechanism of brazilin.

• Corrosion Science and Technology
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• 제4권3호
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• pp.89-94
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• 2005

This paper presents the results of a study that was undertaken to optimize the ratio of the components of a new multi-component inhibitor blend composed of orthophosphate/ phosphonates/ acrylate copolymer/ isothiazolone. The effects of newly developed inhibitor on carbon steel dissolution in synthetic cooling water were studied through weight loss tests, electrochemical tests, scale tests, and micro-organism tests. The obtained results were compared to blank (uninhibited specimen) and showed that developed inhibitor revealed very good corrosion, scale, and micro-organism inhibition simultaneously. All measurements indicated that the efficiency of the blended mixture exceeded 90 %. The inhibitive effects arose from formation of protective films which might contain calcium phosphate, calcium phosphonate, and iron oxide. The nature of protective films formed on the carbon steel was studied by scanning electron microscopy (SEM) and auger electron spe ctroscopy (AES). Inhibitor used in this study appeared to have better performance for scale inhibition due to their superior crystal modification effect and excellent calcium carbonate scale inhibition properties. The effect of inhibitor on microorganisms was evaluated through minimum inhibitory concentration (MIC) test. All kinds of micro-organisms used in this study were inhibited under 78ppm concentration of inhibitor.