• Development and Reproduction
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• v.14 no.2
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• pp.65-74
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• 2010

Placenta has been shown to be a site of expression of several of the monoamine membrane uptake transporters. However, the correlation between the expressions of norepinephrine transporter (NET) and placental development including gynecological diseases is still unknown. To investigate the expression and functions of NET in placenta, we conducted to compare NET expression in normal and preeclamptic placenta and analyzed the function of NET in HTR8-SV/neo trophoblast cells after NET gene transfection. The expression of NET was analyzed in placental tissues from the following groups of patients (none underwent labor): 1) term normal placenta (n=15); 2) term with preeclamptic placeneta (n=15); and 3) pre-term with preeclamptic placenta (n=11) using semi-quantitative RT-PCR, immunohistochemistry, and Western blot. In order to evaluate the function of NET, NET gene plasmid and NET gene-specific siRNA were trnasfected into HTR-8/SVneo trophoblast cells for 24 hours. NET had low expression in the pre-eclamptic placenta compare with normal placenta but no difference in western blot data. NET was expressed in the trophoblasts, and the up-regulation of NET gene stimulated the invasion of HTR-8/SVneo trophoblast cells by 2.5 fold (p<0.05), whereas the NET-siRNA treatment reduced invasion rates. Also, we observed that the expression of NET induces to expression and activity of MMP-9 in HTR-8/SVneo trophoblast cells in zymography. The results suggest that the expression of NET were reduced in pre-eclampsia and should be inhibited invasion activity of trophoblasts. Therefore, these findings provide useful guidelines for the mechanisms of trophoblast invasion as well as for the basic understanding of gynecological diseases including pre-eclampsia.

• Journal of Life Science
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• v.20 no.9
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• pp.1324-1331
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• 2010

Mifepristone (MIF) and Tamoxifen (TAM) have been used in the treatment of prostate cancer and breast cancer for more than a decade. MIF can induce apoptosis in both AR-positive and negative prostate cancer cells. Because of its pleiotropic ligand-receptor properties, TAM exerts cytotoxic activity in estrogen (ER)-positive and various ER.negative cancer cells. However, the molecular mechanisms of these two substances are not yet clear. In the present work, we report that the cytotoxic effects of MIF and TAM are due to the modulation of intracellular $Ca^{2+}$ level in DU-145, androgen-insensitive cells. When the cells were treated with micromolar concentrations of either MIF or TAM, the growth and viability were significantly decreased in a dose- and time-dependent manner. The apoptosis induced by MIF or TAM was further proved and analyzed by confocal laser scanning microscopy (CLSM) and fluorescence-activated cell sorting (FACS). In the cells cultivated in a normal 1.5 mM $Ca^{2+}$ medium, both MIF and TAM also induced an increase of the intracellular $Ca^{2+}$ level in a dose-dependent fashion. Since a change in calcium level could not be found in cells of the $Ca^{2+}$-free medium, the increase of intracellular $Ca^{2+}$ level might be due to an increase in extracellular calcium uptake. Our results show that the apoptotic effect was more prominent in TAM treatment compared to MIF treatment in DU-145 cells. The above findings might be due to the difference in the uppermost pathways of apoptosis induced by either MIF or TAM. When we checked the level of procaspase-8 activation, TAM showed minor level of activation, as opposed to MIF, which exerted strong activation. In both treatments, the levels of anti-apoptotic protein Bcl-2 decreased, and pro-apoptotic protein Bax level increased more than 2-fold. The activation of caspase-3, a key protease enzyme in the downstream pathway of apoptosis, was much higher in the cells treated with TAM, compared to the MIF treatment. The overall apoptotic activity shown in the present work was closely related to intracellular $Ca^{2+}$ concentration levels. Therefore, the cytotoxic activity induced by MIF and TAM might have been due to intracellular calcium modulation.

• The Korean Journal of Pharmacology
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• v.17 no.2
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• pp.23-30
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• 1981

1) Effects of McN-A-343, clonidine and cocaine on the contractile response of the rat and rabbit vas deferens to field stimulation were investigated. The action mechanisms of these drugs have shown to be associated with endogenous norepinephrine(NE). 2) The contractile response to the stimulation of 5-10 Hz was markedly inhibited by the cumulative doses of McN-A-343 (0.003, 0.03, $0.3{\mu}g/ml$), clonidine (0.003, $0.3{\mu}g/ml$) and cocaine $(0.03\;{\mu}g/ml)$. The inhibition was antagonized by yohimbine and pjperoxan. 3) The inhibitory effect of McN-A-343 $(0.03{\mu}g/ml)$ and cocaine $(0.03{\mu}g/ml)$ was markedly enhanced by the same dose of cocaine and McN-A-343, respectively. This enhanced inhibition was also antagonized by yohimbine. 4) The contractile response to the stimulation of 0.01 Hz and 5-10 Hz was markedly potentiated by comparatively large doses of McN-A-343 $(30\;{\mu}g/ml)$ and $(3\;{\mu}g/ml)$. This potentiation was not observed in the presence of thymoxamine. The potentiation by McN-A-343 also did not appear in the presence of atropine. 5) The contractile response to the above stimulation was potentiated by muscarine and the potentiation was markedly attenuated in the presence of thymoxamine and atropine.

• Korean Journal of Environmental Agriculture
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• v.16 no.3
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• pp.249-254
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• 1997

The constructed wetland system which is applicable to rural wastewater treatment was examined by pilot plant experiment. Removal rates of nutrients including nitrogen and phosphorus and total coliform were evaluated. The $NH_4\;^+$ concentration of the influent was in the range of 91.57 to 275.88mg/l and the effluent concentration was about 40% lower than the influent. The decreasing of the $NH_4\;^+$ concentration might be due to volatilization, plant uptake, adsorption onto soil particles, and mainly nitrification. However, generally concentrations of $NO_2\;^-$ and $NO_3\;^-$ were increased in the effluents compared to the influent concentrations, which implies that nitrogen components in the system were nitrified. Overall, the average removal rate of the nitrogen was about 5% which seems inadequate as a wastewater treatment system, and this system needs improvement on nitrogen removal mechamism. The removal rate of the phosphorus was quite high and effluent concentration was very low. Reason for high removal rate of the phosphorus might be mainly strong adsorption characteristic onto soil particles. The average removal rate of the total coliforms was about 83%, and main removal mechanisms are thought to be adsorption onto soil and inability to compete against the established soil microflora. From the results of the study, the constructed wetland system needs to be improved in nitrogen removal mechanism for field application.

• Journal of Wetlands Research
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• v.25 no.2
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• pp.145-158
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• 2023

Constructed wetlands (CWs) are effective technologies for urban wastewater management, utilizing natural physico-chemical and biological processes to remove pollutants. This study employed a bibliometric analysis approach to investigate the progress and future research trends in the field of CWs. A comprehensive review of 100 most-recently published and open-access articles was performed to analyze the performance of CWs in treating wastewater. Spain, China, Italy, and the United States were among the most productive countries in terms of the number of published papers. The most frequently used keywords in publications include water quality (n=19), phytoremediation (n=13), stormwater (n=11), and phosphorus (n=11), suggesting that the efficiency of CWs in improving water quality and removal of nutrients were widely investigated. Among the different types of CWs reviewed, hybrid CWs exhibited the highest removal efficiencies for BOD (88.67%) and TSS (95.67%), whereas VSSF, and HSSF systems also showed high TSS removal efficiencies (83.25%, and 78.83% respectively). VSSF wetland displayed the highest COD removal efficiency (71.82%). Generally, physical processes (e.g., sedimentation, filtration, adsorption) and biological mechanisms (i.e., biodegradation) contributed to the high removal efficiency of TSS, BOD, and COD in CW systems. The hybrid CW system demonstrated highest TN removal efficiency (60.78%) by integrating multiple treatment processes, including aerobic and anaerobic conditions, various vegetation types, and different media configurations, which enhanced microbial activity and allowed for comprehensive nitrogen compound removal. The FWS system showed the highest TP removal efficiency (54.50%) due to combined process of settling sediment-bound phosphorus and plant uptake. Phragmites, Cyperus, Iris, and Typha were commonly used in CWs due to their superior phytoremediation capabilities. The study emphasized the potential of CWs as sustainable alternatives for wastewater management, particularly in urban areas.