• Advances in environmental research
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• v.5 no.3
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• pp.189-200
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• 2016

This study aimed at advanced oxidation of hetero tri-functional reactive dye Acid orange 7 using photo-Fenton conditions in a lab-scale experiment. Decolourisation of Acid Orange 7 dye by Fenton's process was dependent on concentration of Hydrogen peroxide, Ferrous sulphate, pH, and contact time. A $2^3$ factorial design was used to evaluate the effects of these key factors: pH, Fe(II), and $H_2O_2$ concentration, for a dye concentration of 50 mg/L with COD of 340 mg/L at pH 3.0. The response function was removal of colour under optimised conditions; pH 3.0, [Fe(II)] 40.83 mg/L, [$H_2O_2$] 4.97 mmol/L; 13.6 min. of treatment resulting in 100% colour removal. The final COD of treated wastewater was nil suggesting that AOP is a potentially useful process of color removal and dye degradation/mineralisation of effluent having AO7. Minimum contact time for complete decolourisation was at 5 mmol/l $H_2O_2$ concentration. Increase in $FeSO_4$ (mg/l) concentration resulted in decrease of time for complete decolourisation. Box-Behnken Design was used to optimize the process variables. Maximum and minimum levels of pH (3-5), $H_2O_2$ (4-6 mmol/l), $FeSO_4$ (30-46 mg/l) and contact time (5-15 minutes) were used. The statistical analysis revealed a value of 0.88 for coefficient of regression ($R^2$) indicating a good fit of model. Calculated F-value was found higher than the tabulated value confirming to significance of the model. Based on student's t-test, Ferrous sulphate, pH, and contact time have a positive effect on the percent decolourisation of Acid Orange 7.

• Journal of Life Science
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• v.13 no.1
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• pp.118-127
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• 2003

$\rho$-Fluorophenylalanine (FPA), a phenylalanine analog, is able to induce apoptotic cell death of human acute leukemia Jurkat T cells. To better understand the mechanism by which FPA induces apoptotic cell death, the effect of ectopic expression of antiapoptotic proteins, Bcl-2 and Bcl-xL, on FPA-induced apoptosis was investigated by employing lurkat T cells transfected with Bcl-2 gene (JT/Bcl-2) or Bcl-xL gene (1/Bcl-xL) and Jurkat T cells transfected with vector (JT/Neo or J/Neo). When Jurkat T cells, JT/Neo or J/Neo, were exposed to FPA at concentrations ranging from 0.63 to 5.0 mM, the cell viability determined by MTT assay declined in a dose-dependent manner. In addition, apoptotic DNA fragmentation along with several apoptotic events such as caspase-8 activation, Bid cleavage, mitochondrial cytochrome c release, caspase-9 activation, caspase-3 activation, and degradation of PARP was induced. However, the FPA-induced cytotoxic effect, activation of caspase-8, and cleavage of Bid were significantly abrogated by ectopic expression of Bcl-2 or Bcl-xL. At the same time, there was marked reduction in the level of cytochrome c release from mitorhondria, caspase-9 activation, caspase-3 activation, and degradation of PARP. These results indicate that caspase-8 activation, Bid cleavage, and mitochondrial cytochrome c release with subsequent activation of the caspase cascade are negatively regulated by Bcl-2 or Bcl-xL, and are thus required for FPA-induced apoptosis in Jurkat T cells

• Toxicological Research
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• v.25 no.4
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• pp.181-188
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• 2009

Uncontrolled cell growth and increased cell proliferation are major features of cancer that are dependent on the stable structure and dynamics of the cytoskeleton. Since stable cytoskeleton structure and dynamics are partly regulated by myosin light chain kinase (MLCK), many current studies focused on MLCK inhibition as a chemotherapeutic target. As a potent and selective MLCK inhibitor, ML-7 [1-(5-iodonaphthalene-1-sulfonyl)-1 H-hexahydro-1,4-diazapine hydrochloride] is a promising candidate for an anticancer agent, which would induce apoptosis as well as prevents invasion and metastasis in certain types of cancer cells. This study assessed cytotoxic effects of ML-7 against HL-60 cells and therapeutic efficacy of ML-7 as a potential antileukemia agent. Trypan-blue exclusion assays showed dose- and time- dependent decreases in ML-7 treated HL-60 cells (p<0.05). Comet assays revealed a significant increase in DNA damage in HL-60 cells after treatment with $40{\mu}M$ ML-7 for 2h. Sub-G1 fractions, analyzed by flow cytometry increased in a dose-dependent manner, suggesting that ML-7 can induce apoptotic cell death in HL-60 cells. ML-7 was selectively cytotoxic towards HL-60 cells; not affecting normal human lymphocytes. That selective effect makes it a promising potential anti-leukemia agent. In addition, anticancer efficacy of ML-7 in combination with flavonoids (genistein or quercetin) or anticancer drugs (cisplatin or Ara-C) against HL-60 cells was assessed. Combination of ML-7 with flavonoids increased the anti-cancer effect of ML-7 to a greater extent than combination with the anticancer drugs. This implies that ML-7 in combination with flavonoids could increase the efficacy of anticancer treatment, while avoiding side effects cansed by conventional anticancer drug-containing combination chemotherapy.

• The Korean Journal of Physiology
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• v.22 no.1
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• pp.13-29
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• 1988

In order to elucidate the regulatory mechanism of intracellular calcium ion concentrations, contractions or contractures induced by $Na^{+}-removal$, calcium-application or ouabain-treatment as an index of $Na^+/Ca^{2+}$ exchange activity were studied in atrial muscle or vascular smooth muscle (aorta and renal artery) of the rabbit. The magnitude of low sodium contractures in atrial trabeculae increased with sigmoid shape when external sodium concentrations were reduced to sodium-free condition, whereas that of calcium contracture intensified in a parabolic pattern when external calcium concentrations were elevated to 8 mM. $Na^{+}-removal$ contractures were induced in a duration-dependent manner to $K^{+}-free$ exposure and same findings were observed with ouabain treatment. $Na^{+}-free$ contractures were not affected by verapamil treatment, but stimulated by $100{\mu}M\;Mn^{2+}$ and inhibited by high concentrations of $Mn^{2+}\;(2{\sim}8mM)$ in a dose-dependent manner. Ryanodine which is known to suppress the release of calcium from internal store abolished spontaneous twitch contractions induced by $K^{+}-free$ solution, but had no effect on the development $Na^{+}-free$ contractures. Na-free contractures were not always induced in vascular smooth muscle preparations. Contractures by $O\;mM\;Na^+$ were usually seen in aorta, but not often in renal artery.$50\;mM\;K^+$, noradrenaline (NA) and angiotensin II (AII) always evoked very large contraction in all preparations of vascular smooth muscle. Contractures developed by $O\;mM\;Na^+$ were not sensitive to verapamil treatment as in atrial trabeculae, but were abolished by $100{\mu}M\;Mn^{2+}$. In contrast to $Na^{+}-free$ contractures, $Mn^{2+}(100{\mu}M)$ had no effect on the contractures induced by NA or 50 mM$K^+$. Caffeine in the concentration of 10 mM evoked transient contracture in the distal renal artery. The rate of spontaneous relaxation in caffeine contracture was dependent upon the concentrations of external sodium, and had double component of relaxation when the rate of relaxation was plotted in the semilogarithmic scale of relative tension versus time. Especially late components of relaxation had more direct relation to $Na^+$ concentrations. It could be concluded that $Na^+/Ca^{2+}$ exchange mechanism in the heart has a large capacity, inhibited by $Mn^{2+}$ but not by verapamil and ryanodine, while $Na^+/Ca^{2+}$ exchange system in vascular smooth muscle has a very low capacity especially in small artery, inhibited by low concentration of $Mn^{2+}\;(100{\mu}M)$ but not affected by verapamil and ryanodine.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.37 no.1
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• pp.1-16
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• 2024

Objectives : We aimed to study the effect of Smilax China L.(SCL), which has anti-inflammatory, antioxidant, and anticancer effects, on the growth of skin cancer cells. Methods : HaCaT cells, a normal human cell line, and skin cancer cells including A431, SK-MEL-5 and SK-MEL-28 cells were treated with Smilax China L. ethanol extract(SCL-EtOH) at concentrations of 5, 10, 20 and 40㎍/㎖. Meanwhile, JB6 Cl41, a normal mouse epithelial cell line, was treated with epidermal growth factor(EGF) and phorbol 12-myristate 13-acetate(TPA), an inflammatory factor, to induce cell transformation and treated with SCL-EtOH. In addition, we treated SK-MEL-5 and SK-MEL-28 cells with SCL-EtOH at various concentrations and checked the effect on the cell cycle. Results : As a result, it showed no toxicity to HaCaT cells up to the highest concentration of 40㎍/㎖, and significant cell growth inhibition to A431, SK-MEL-5 and SK-MEL-28 cells in a time- and concentration-dependent manner. In addition, as a result of checking the shape of skin cancer cells according to SCL-EtOH treatment, it was observed that as the concentration increased, the number of normally attached and growing cells decreased and the shape of the cells changed. Colony formation was significantly reduced in a concentration-dependent manner in JB6 Cl41 cells treated with EGF or TPA. Flow cytometry analysis with propidium iodide(PI) staining showed that SCL-EtOH induced the G2/M phase arrest. We further confirmed the decrease in Cyclin B1 expression and increase in p27 expression associated with the G2/M phase of the cell cycle through western blot analysis. Flow cytometry analysis confirmed that SCL-EtOH induced cell apoptosis. Furthermore, through Western blot analysis, it was observed that the expression of cleaved-caspase-7, which is related to apoptosis, increased. Finally, it was confirmed that the expression of COX-2, an inflammatory marker protein, decreased in a concentration-dependent manner with SCL-EtOH. Conclusions : Through the above results, we have established a basis for applying SCL to the treatment of skin cancer.

• Journal of the Korea Concrete Institute
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• v.19 no.6
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• pp.693-700
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• 2007

The maturity method is used to estimate the effects of time and temperature on the strength development of concrete. The purpose of this paper is to show how variable curing temperatures affect strength development for both normal and high-strength concrete using the maturity concept. The experimental results for normal-strength concrete show clearly the cross-over effect of strength development as the time of the peak temperature varied. However, this cross-over effect does not exist after the actual ages are converted to the temperature dependent equivalent age. In other words, the existing maturity method does not include the effect of varying the time to peak temperatures but instead includes the effect of the magnitude of peak temperatures. For high-strength concrete, the results were inconclusive. This fact for normal-strength concrete coincides with the ASTM stated limitation that the existing maturity method doesn't take into account the effect of early age temperature on long-term ultimate strength. The results of this 3-year study are used as a basis for an improved concrete maturity function.

• Journal of Acupuncture Research
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• v.18 no.4
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• pp.101-115
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• 2001

Objective : To characterize the antitumorigenic potential of Apamin, one of the major components of bee venom, its effects on cell proliferation and the mitogen-activated protein kinase (MAPK) signal transduction pathway were characterized using the human melanoma cell line SK-MEL-2. Methods & Results : Cell counting analysis for cell death demonstrated that consistent with a previous results, SK-MEL-2 cells treated with $0.5-2.0{\mu}g/ml$ of Apamin showed no recognizable cytotoxic effect whereas detectable induction of cell death was identified at concentrations over $5.0{\mu}g/ml$. [3H]thymidine incorporation assay for cell proliferation demonstrated that DNA replication of SK-MEL-2 cells is inhibited by Apamin in a dose- and time-dependent manner. To explore whether Apamin-induced growth suppression is associated with the MAPK signaling pathway, phosphorylation of Erk, a function mediator of MAPK growth-stimulating signal, was examined Western blot assay using a phospho-specific Erkl/2 antibody. A significant increase of Erkl/2 phosphorylation level was observed in Apamin-treated cells compared with untreated control cells. Qantitative RT-PCR analysis revealed that Apamin inhibit expression of MAPK downstream genes such as c-Jun, c-Fos, and cyclin D1 but not expression of MAPK pathway component genes including Ha-Ras, c-Raf-1, MEK1, and Erk. Conclusion : It is strongly suggested that the antitumorigenic activity of Apamin might result in part from its inhibitory effect on the MAPK signaling pathway in human melanoma cells SK-MEL-2.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.5
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• pp.1016-1019
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• 2002

To examine the cytotoxic effect of glucose oxidase(GO) in cultured mouse cerebral neurons, cytotoxicity was measured by MTT assay after cultured nerve cells were incubated for 3 hours in the media containing 1 ～ 60mU/ml concentrations of GO. In addition, the neuroprotective effect of Ramulus et uncus uncariae(REUU) was determined by MTT assay in these cultrures. Cell viability was remarkably decreased in a dose- and time-dependent manner after cultured mouse cerebral neurons were exposed to 30mU/ml GO for 3 hours. In the neuroprotective effect of REUU on GO-induced toxicity, REUU blocked the GO-mediated neurotoxicity in these cultures. From above the results, it suggests that GO is toxic in cultured mouse cerebral neurons and selective herb extract such as REUU is effective in prevetion of the neurotoxicity induced by GO.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.764-767
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• 2002

To evaluate the osteotoxic effect of methylmercuric chloride(MMC) on cultured mouse osteoblasts, cytotoxic effect was measured by MTT assay after cultured mouse osteoblasts were incubated with various concentrations of MMC for 20 hours. The protective effect of Flos Carthami(FC) against MMC-induced osteotoxicity was also examined in these cultures. MMC decreased cell viability of cultured mouse osteoblasts remarkably in a dose- and time-dependent manners. In protective effect of FC was remarkably effective in blocking the osteotoxicity induced by MMC. From aboved the results, it is suggested that MMC induce osteotoxicity, and the selective herba extract such as FC is very effective in blocking MMC-mediated neurotoxicity on cultured mouse osteoblasts.

• Journal of Energy Engineering
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• v.7 no.2
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• pp.163-171
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• 1998

Degradation of polymer additives is enhanced at higher temperature of the test solutions. The degradation of Co-polymer solution was investigated experimentally in a closed loop at the temperature of 6$0^{\circ}C$ and 8$0^{\circ}C$ with various polymer concentrations of 100, 200, 400, 600 ppm in order to see the effect of temperature and polymer concentration with time. The degradation effect were found to be more dependent on temperature than mechanical shear. The friction factor versus Reynolds number curves show that in the range of Reynolds number number 50,000~150,000 the friction was decreased as Reynolds number increased and the friction of solution at low temperature approached to Virk's maximum drag reduction asymptote. For constant flowrates and temperatures the degradation effect was found to be less likely in higher polymer concentration. For constant flowrates and polymer concentrations the degradation rates are affected mainly by temperature. At the temperature of 8$0^{\circ}C$ and polymer concentration of 100 ppm, drag reduction effect was disappeared after 4 hours. However, this thermal degradation could be avoided with additional materials such as surfactants which are supposed to enhance the bonding forces between polymer molecules.