• The Korean Journal of Physiology and Pharmacology
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• v.4 no.1
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• pp.9-14
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• 2000

$K^+$ currents play multiple roles in the excitability of dorsal root ganglion (DRG) neurons. Influences on these currents change the shape of the action potential, its firing threshold and the resting membrane potential. In this study, whole cell configuration of patch clamp technique had been applied to record the blocking effect of capsaicin, a lipophilic alkaloid, on the delayed rectifier $K^+$ current in cultured small diameter DRG neurons of adult rat. Capsaicin reduced the amplitude of $K^+$ current in dose dependent manner, and the concentration-dependence curve was well described by the Hill equation with $K_D$ value of $19.1{\mu}M.$ The blocking effect of capsaicin was reversible. Capsaicin $(10 {\mu}M)$ shifted the steady-state inactivation curve in the hyperpolarizing direction by about 15 mV and increased the rate of inactivation. The voltage dependence of activation was not affected by capsaicin. These multiple effects of capsaicin may suggest that capsaicin bind to the region of $K^+$ channel, participating in inactivation process.

• YAKHAK HOEJI
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• v.50 no.4
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• pp.278-286
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• 2006

Classical dihydropyrrole[3,4-f]quinazoline antifolates 7,8 and 9, in which the tricyclic ring is structurally similar to the pteridine ring of $CH_2-THF(1)$, the cofactor of thymidylate synthase (TS), were synthesized, and their in vitro antitumor activity was evaluated by measuring the cell growth inhibitory activity against cancer cell lines. The target compounds were cytotoxic against CCRF-CEM, human T-cell acute lymphoblastic leukemia, with the cell growth inhibitory activity $(IC_{50})$ of $0.8{\sim}8.3\;{\mu}M$. Among the three compounds, 3-amino analog 7 was 10- and 3.5-fold more cytotoxic compared to the 3-methyl analogs 8 and 9, and its cytotoxicity was similar to that of the reference compound with the $IC_{50}$ value of $0.83\;{\mu}M$. This result was supposed as the consequence of the fact that dihydropyrroloquinazolinone ring with amino group was able to bind well in the active site of TS. In the case of 3-methyl analogs, analog 9, which has two-carbon bridge between the dihydropyrroloquinazolinone ring and benzoyl-L-glutamic acid, was 3-times more potent in cytotoxicity than analog 8 which has one-carbon bridge, and this result indicates that the distance and conformational orientation of the benzoyl-L-glutamic acid moiety with respect to the tricyclic ring may also be a crucial determinant of cell growth inhibitory activity.

• Corrosion Science and Technology
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• v.21 no.2
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• pp.89-99
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• 2022

A versatile method for performing non-cyanide electroless gold plating using thiomalic acid (TMA) as a complexing agent and 2-aminoethanethiol (AET) as a reducing agent was investigated. It was found that TMA was an excellent complexing agent for gold. It can be used in electroless gold plating baths at a neutral pH with a high solution stability, makes it a potential candidate to replace conventional toxic cyanide complex. It was found that one gold atomic ion could bind to two TMA molecules to form the [2TMA-Au⁺] complex in a solution. AET can be used as a reducing agent in electroless gold plating solutions. The highest current density was obtained at electrode rotation rate of 250 to 500 rpm based on anodic and cathodic polarization curves with the mixed potential theory. Increasing AET concentration, pH, and temperature significantly increased the anodic polarization current density and shifted the plating potential toward a more negative value. The optimal gold ion concentration to obtain the highest current density was 0.01 M. The cathodic current was higher at a lower pH and a higher temperature. The current density was inversely proportional to TMA concentration.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7737-7741
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• 2013

Background: Human papilloma virus infection is associated with genesis and malignant potential of cervical cancer. E6 and E7 oncogens are known to bind to p53 and retinoblastoma gene products, abrogating their functions as tumor suppressors, leading to an abnormal cell cycle machinery. Roles of the p53 homolog p63 have also been postulated, E6 expression leading to TAp63b degradation allowing anchorage independent growth. Molecular studies correlated with clinicopathological factors are important to determine prognosis and treatment strategies, but results have been controversial and need to be clarified. Aim: To investigate expression of p53 and p63 in cervical squamous cell carcinomas in correlation with age, FIGO staging, morphology, and cancer cell proliferation. Materials and Methods: Expression of p53 and p63 immunohistochemical staining in a total of 56 paraffin-embedded tissues of cervical squamous cell carcinomas from Dr. Sardjito General Hospital Indonesia, was evaluated for correlation with clinicopathological parameters. The Mann-Whitney test was used to compare the percentage of p53 and p63 expression with patient age, FIGO staging and morphology and to compare mean p53 and p63 expression. The Spearman correlation test was applied to correlate p53 and p63 expression with that of Ki-67. A p-value of <0.05 was considered statistically significant. Results: There were significant associations between p53 expression with age (p=0.019) and FIGO staging (p=0.026), but not with with morphology or Ki-67 expression. There were no links between p63 expression and age, morphology, FIGO staging or Ki-67. Conclusions: This study indicated that p53 has a prognostic value in cervical squamous cell carcinomas given the relation with FIGO staging.

• Toxicological Research
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• v.21 no.2
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• pp.161-165
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• 2005

Bisphenol A (SPA), a environmental endocrine disruptor, is considered to bind to estrogen receptors and to regulate the expressions of estrogen responsive genes. This study was to evaluate the effect of SPA administration on body weight, sex ratio and litter size on 18 days in prenatal periods, the effect of reproductive organ weight and blood hematological values on 24 days postpartum in pregnant mice. The female mice was administrated to low doses of SPA (0, 0.05, 0.5 and 5.0 mg/kg B.W.) by intraperitoneal injection in gestation days $0\~15$ with 5 times at 3 days interval. The maternal body weight, litter size and sex ratios were similar to in all experimental groups, but body weights of male and female offspring was significantly lower in 5.0mg SPA group when compared to any other groups (P<0.05). No treatment-related effects on body weight, ovary weight and blood hematological values were observed in dams on 24 days after delivery. The uterine weight in 5.0mg SPA group was slightly higher than those of any other groups, but not significantly difference. The histological evaluation of ovary in dam mice on 24 days after dilivery was not difference in all experimental groups, but the endometriosis of uterus in dam mice were significantly increased in 0.5mg SPA group when compared to control group. These results indicates that low concentration of SPA should not be considered as a selective reproductive toxicant.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.1
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• pp.166-183
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• 2013

It requires a lot of costs and manpower to manage an election. The electronic voting scheme can make the election system economic and trustful. The widespread use of smart phones causes mobile voting to be a major issue. The smart phone can be used as a mobile voting platform since it can carry out many services in addition to basic telephone service. To make mobile voting practical and trustful, we analyzed two subjects of study. Firstly, the way to make a biometric based mobile ID, which has legal binding forces. In mobile voting, user identification is accomplished on line since the voter should be able to vote wherever they go. The digital ID conducts a similar role to the need for a resident card. The user's identity is bound to the resident card legally. To bind the user's identity to the smart phone, we use USIM. Biometric recognition is also needed to authenticate the user, since the user cannot prove him or her on line face-to-face. The proposed mobile ID can be reissued by means of introducing a random secret value. Secondly, the mobile voting scheme is proposed where candidates can accept election results without doubt. The goal of an election is to select a leader among two or more candidates. Existing electronic voting schemes mainly focus on the study of ballot verification accomplished by voters. These approaches are not safe against collusion attacks where candidates and the election administration center are able to collude to fabricate election results. Therefore, a new type of voting and counting method is needed where candidates can directly take part in voting and counting stages. The biometric based multi-signature scheme is used to make the undeniable multi-signed ballot. The ballot cannot be verified without the help of all candidates. If candidates accept election results without a doubt, the fairness of the election is satisfied.

• Rapid Communication in Photoscience
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• v.3 no.4
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• pp.81-84
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• 2014

To examine the microenvironmental effect of DNA on the photosensitized reaction, the electron-donor-connecting porphyrin, meso-(9-phenanthryl)-tris(N-methyl-p-pyridinio) porphyrin (Phen-TMPyP), was synthesized. Phen-TMPyP can bind to oligonucleotides with two binding modes, depending on the DNA concentration. The fluorescence lifetime measurement of Phen-TMPyP shows a shorter component than that of the reference porphyrin without the phenanthryl moiety. However, the observed value is much longer than those of previously reported similar types of electron-donor-connecting porphyrins, suggesting that electron-transfer quenching by the phenanthryl moiety is not sufficient. The fluorescence quantum yield of Phen-TMPyP ($5{\mu}M$) decreased with an increase in DNA concentration of up to $5{\mu}M$ base pair (bp), possibly due to self-quenching through an aggregation along the DNA strand, increased with an increase in DNA concentration of more than $5{\mu}M$ bp and reached a plateau. The fluorescence quantum yield of Phen-TMPyP with a sufficient concentration of DNA was larger than that of the reference porphyrin. The singlet oxygen ($^1O_2$) generating activity of Phen-TMPyP was confirmed by the near-infrared emission spectrum measurement. The quantum yield of $^1O_2$ generation was decreased by a relatively small concentration of DNA, possibly due to the aggregation of Phen-TMPyP, and recovered with a sufficient concentration of DNA. The recovered quantum yield was rather smaller than that without DNA, indicating the quenching of $^1O_2$ by DNA. These results show that a DNA strand can stabilize the photoexcited state of a photosensitizer and, in a certain case, suppresses the $^1O_2$ generation.

• The Plant Pathology Journal
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• v.20 no.4
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• pp.252-257
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• 2004

We developed a polyclonal antibody based-ELISA system to monitor inocula accurately and rapidly before onset of anthracnose on soybean sprouts. Titer of mouse antisera against conidia of Colletotrichum gloeosporioides, determined by indirect ELISA, was high enough to be detectable up to ${\times}$25,600 dilutions. Both PAb1 and PAb2 had the highest level of reactivity to Colletotrichum gloeosporioides. Absorbance readings exceeded 0.15. Sensitivity of PAb to C. gloeosporioides was precise enough to detect spore concentration as low as 500 conidia/well by indirect ELISA. Both antibodies are very sensitive and highly specific to the target pathogen Colletotrichum gloeosporioides, apparently discriminating other unrelated pathogen, or epiphytes. This kit fulfills the requirements far detecting inocula before infection and onset of anthracnose. Our ELISA system should also be feasible to detect C. acutatum (Mungbean sprouts rot) and G. cingulata (C. gleosporioides), (apple, pepper). It was remarkable that absorbance value was not reduced even after 4 consecutive washings (Fig.4), suggesting that antigenic determinants are on the surface of conidia. Antigenic determinant was characterized by heating and enzyme treatment: Both PAb1 and PAb2 bind to protein epitope that does not contain residue of amino acid, arginine, and Iysine, even though more work needs to be done.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.481-486
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• 1993

A computeized least-cost formulation program was applied to process emulsion-type sausages. The input data in formulation were utilized with the database which had been established in the previous study. The formulation results may provide Korean meat processors with actual examples. Meat-grade system made these examples more useful. The results of manufacturing test were as follows. The actual cohesiveness from manufactured sausages didn't correspond to the predicted values, but increased as the predicted values increased. These gabs caused by the different processing conditions between the model system and the actual processing. Hardness as well as cohesiveness could be used as the desirable index of a sausage texture. Comparing the cohesiveness and hardness of commercial frankfurters with those of test sausages, bind value constraint of $0.16{\sim}0.17$ in this test formula can be utilized for an actual formulation.

• Journal of Powder Materials
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• v.27 no.5
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• pp.401-405
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• 2020

Magnesium hydroxide sulfate hydrate (MHSH) whiskers were synthesized via a hydrothermal reaction by using MgO as the reactant as well as the acid solution. The effects of the H₂SO₄ amount and reaction time at the same temperature were studied. In general, MHSH whiskers were prepared using MgSO₄ in aqueous ammonia. In this work, to reduce the formation of impurities and increase the purity of MHSH, we employed a synthesis technique that did not require the addition of a basic solution. Furthermore, the pH value, which was controlled by the H₂SO₄ amount, acted as an important factor for the formation of high-purity MHSH. MgO was used as the raw material because it easily reacts in water and forms Mg⁺ and MgOH⁺ ions that bind with SO₄^2- ions to produce MHSH. Their morphologies and structures were determined using X-ray diffraction (XRD) and scanning electron microscopy (SEM).