• The Korean Journal of Physiology
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• v.28 no.2
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• pp.215-224
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• 1994

The presence of a calcium current $(i_{Ca^{2+}})$ passed via a specific channel was examined in the unfertilized hamster egg using the whole-cell voltage clamp technique. Pure inward current was isolated using a $Ca^{2+}-rich$ pipette solution containing 10 mM TEA. This current was independent of external $Na^+$ and was highly sensitive to the $Ca^{2+}$ concentration in the bathing solution, indicating that the inward current is carried by $Ca^{2+}$. The maximal amplitude was $-4.12{\pm}0.58nA\;(n=12)$ with 10mM $Ca^{2+}$ at -3OmV from a holding potential of -8OmV. This current reached its maximum within 20ms beyond -3OmV and decayed rapidly with an inactivation time constant $({\tau})$ of 15ms. Activation and inactivation of this $i_{Ca^{2+}}$ was steeply dependent on the membrane potential. The $i_{Ca^{2+}}$ began to activate at the lower voltage of -55 mV and reached its peak at -35 mV, being completely inactivated at potentials more positive than -40 mV. These result suggest that $i_{Ca^{2+}}$ in hamster eggs passes through channels with electrical properties similar to low voltage-activated T-type channels. Other results from the present study support this suggestion; First, the inhibitory effect of $Ni^{2+}\;(IC_{50}=13.7\;{\mu}M)$ was more potent than $Cd^{2+}\;(IC_{50}=123\;{\mu}M)$. Second, $Ba^{2+}$ conductance was equal to or below that of $Ca^{2+}$. Third, $i_{Ca^{2+}}$ in hamster eggs was relatively insensitive to nifedipine $(IC_{50}=96.6\;{\mu}M)$, known to be a specific t-type blocker. The physiological role of $i_{Ca^{2+}}$ in the unfertilized hamster eggs remains unclear. Analysis from steady-state inactivation activation curves reveals that only a small amount of this current will pass in the voltage range $(-70{\sim}-30\;mV)$ which partially overlaps with the resting membrane potential. This current has the property that it can be easily activated by a weak depolarization, thus it may trigger a certain kind of a intracellular event following fertilization which may cause oscillations in the membrane potential.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1636-1648
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• 2006

There are detailed descriptions of the clinical experiences and prescriptions of asthma in traditional Korean medicine. Zedoariae rhizoma is one of the Korean herbal medicines used to treat bronchial asthma and allergic rhinitis for centuries. However, the therapeutic mechanisms of this medication are still far from clear, In this study, a house-dust-mite (Dermatophagoides pteronyssinus [Der p])-sensitized murine model of asthma was used to evaluate the immunomodulatory effect of Zedoariae rhizoma on the allergen-induced airway inflammation in asthma. Three different protocols were designed to evaluate the treatment and/or long-term prophylacitic effect of Zedoariae rhizoma in Der p-sensitized mice. Cellular infiltration and T-cell subsets in the bronchoalveolar lavage fluid (BALF)of allergen-challenged mice were analyzed. Intrapulmonary lymphocytes were also isolated to evaluate their response to allergen stimulation. When Zedoariae rhizoma was administered to the sensitized mice before AC (groups A and C), it suppressed airway inflammation by decreasing the number of total cells and eosinophil infiltration in the BALF, and downregulated the allergen- or mitogen-induced intrapulmonary lymphocyte response of sensitized mice as compared to those of controls. This immunomodulatory effect of Zedoariae rhizoma may be exerted through the regulation of T-cell subsets by elevation or activation of the CD8+ and double-negative T-cell population in the lung. However, the administration of Zedoariae rhizoma to sensitized mice 24 h after AC (group B) did not have the same inhibitory effect on the airway inflammation as Zedoariae rhizoma given before AC. Thus, the administration of Zedoariae rhizoma before AC has the immunomodulatory effect of reducing bronchial inflammation in the allergen-sensitized mice. On the other hand, to determine the potentiality of prophylactic and/or therapeutic approaches using a traditional herbal medicine, Zedoariae rhizoma, for the control of allergic disease, we examined the effects of oral administration of Zedoariae rhizoma on a murine model of asthma allergic responses. When oral administration of Zedoariae rhizoma was begun at the induction phase immediately after OVA sensitization, eosinophilia and Th2-type cytokine production in the airway were reduced in OVA-sensitized mice following OVA inhalation. These results suggest that the oral administration of Zedoariae rhizoma dichotomously modulates allergic inflammation in murine model for asthma, thus offering a different approach for the treatment of allergic disorders.

• Clinical and Experimental Reproductive Medicine
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• v.44 no.3
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• pp.152-158
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• 2017

Objective: To identify the associations between polymorphisms of the 3'-untranslated region (UTR) of methylenetetrahydrofolate reductase (MTHFR) gene, which codes for an important regulatory enzyme primarily involved in folate metabolism, and idiopathic recurrent pregnancy loss (RPL) in Korean women. Methods: The study population comprised 369 RPL patients and 228 controls. MTHFR 2572C > A, 4869C > G, 5488C > T, and 6685T > C 3'-UTR polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis or by TaqMan allelic discrimination assays. Natural killer cell proportions were determined by flow cytometry. Results: The MTHFR 2572-5488-6685 (A-C-T) haplotype had an adjusted odds ratio of 0.420 (95% confidence interval, 0.178-0.994; p= 0.048) for RPL. Analysis of variance revealed that MTHFR 4869C > G was associated with altered $CD56^+$ natural killer cell percentages (CC, $17.91%{\pm}8.04%$; CG, $12.67%{\pm}4.64%$; p= 0.024) and folate levels (CC, $12.01{\pm}7.18mg/mL$; CG, $22.15{\pm}26.25mg/mL$; p= 0.006). Conclusion: Variants in the 3'-UTR of MTHFR are potential biomarkers for RPL. However, these results should be validated in additional studies of ethnically diverse groups of patients.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5785-5790
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• 2012

The use of chemotherapeutics induces cardiotoxicity and affects immune functions, therefore development of combinatorial agents against cardiotoxicity and immunosuppression needs to be explored. Previous studies of the hexane insoluble fraction (HIF) of an ethanolic extract of Ficus septica leaves showed anticancer effects singly and in combination with doxorubicin on T47D breast cancer cells. In this present study, it was evaluated for its immunomodulatory activities in doxorubicin-treated rats. Thirty male Sprague Dawley rats were divided into five groups consisting of six rats each as follows: Group 1, receiving oral saline 10 ml/kg BW (control group); Group 2, receiving HIF dose 750 mg/kg BW orally, once daily; Group 3, receiving HIF dose 1.500 mg/kg BW orally, once daily; Group 4, given oral saline 10 ml/kg BW (normal group); Group 5, receiving HIF dose 1.500 mg/kg BW orally, once daily. The rats of group 1-3 were intramuscularly administered with doxorubicin at a dose of 4.67 mg/kg BW at the days 1 and 4 to suppress immune functions. Concomitantly, the rats were treated with saline or HIF for seven consecutive days (1 to 7). Treatment of HIF succeeded in reducing side effects of doxorubicin based on increasing lymphocyte density and phagocytosis activity and capacity of macrophages, as well as increasing the CD8+ blood level and decreasing spleen IL-10 expression. Hexane insoluble fraction of of ethanolic extract of Ficus septica leaves has potential as a protective agent combined with doxorubicin.

• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.122-135
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• 2018

Listeriolysin O (LLO), one of the most immunogenic proteins of Listeria monocytogenes and its main virulence factor, mediates bacterial escape from the phagosome of the infected cell. Thus, its expression in a nonpathogenic bacterial host may enable effective delivery of heterologous antigens to the host cell cytosol and lead to their processing predominantly through the cytosolic MHC class I presentation pathway. The aim of this project was to characterize the delivery of a model antigen, chicken egg ovalbumin (OVA), to the cytosol of dendritic cells by recombinant Bacillus subtilis vegetative cells expressing LLO. Our work indicated that LLO produced by non-sporulating vegetative bacteria was able to support OVA epitope presentation by MHC I molecules on the surface of antigen presenting cells and consequently influence OVA-specific cytotoxic T cell activation. Additionally, it was proven that the genetic context of the epitope sequence is of great importance, as only the native full-sequence OVA fused to the N-terminal fragment of LLO was sufficient for effective epitope delivery and activation of $CD8^+$ lymphocytes. These results demonstrate the necessity for further verification of the fusion antigen potency of enhancing the MHC I presentation, and they prove that LLO-producing B. subtilis may represent a novel and attractive candidate for a vaccine vector.

• BMB Reports
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• v.38 no.5
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• pp.624-631
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• 2005

Tuberculosis, caused by Mycobacterium tuberculosis, continues to be one of the main diseases to mankind. It is urgent to discover novel drug targets for appropriate antimicrobial agents against this human pathogen. The shikimate pathway is onsidered as an attractive target for the discovery of novel antibiotics for its essentiality in bacteria and absence in mammalian cells. The Mycobacterium tuberculosis aroE-encoded shikimate dehydrogenase was cloned, expressed and purified. Sequence alignment analysis shows that shikimate dehydrogenase of Mycobacterium tuberculosis exhibit the pattern of G-X-(N/S)-V-(T/S)-X-PX-K, which is highly conserved within the shikimate dehydrogenase family. The recombinant shikimate dehydrogenase spectrum determined by CD spectroscopy showed that the percentages for $\alpha$-helix, $\beta$-sheet, $\beta$-turn, and random coil were 29.2%, 9.3%, 32.7%, and 28.8%, respectively. The enzymatic characterization demonstrates that it appears to be fully active at pH from 9.0 to 12, and temperature $63^{\circ}C$. The apparent Michaelis constant for shikimic acid and $NADP^+$ were calculated to be about $29.5\;{\mu}M$ and $63\;{\mu}M$. The recombinant shikimate dehydrogenase catalyzes the substrate in the presence of $NADP^+$ with an enzyme turnover number of $399\;s^{-1}$. Zymological studies suggest that the cloned shikimate dehydrogenase from M. tuberculosis has a pretty activity, and the work should help in the discovery of enzyme inhibitors and further of possible antimicrobial agents against Mycobacterium tuberculosis.

• BMB Reports
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• v.40 no.3
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• pp.412-418
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• 2007

Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is an unique antioxidant enzyme that directly reduces lipid hydroperoxides in biomembranes. In the present work, the entire encoding region for Oryza sativa PHGPx was expressed in Escherichia coli M15, and the purified fusion protein showed a single band with 21.0 kD and pI = 8.5 on SDS- and IFE-PAGE, respectively. Judging from CD and fluorescence spectroscopy, this protein is considered to have a well-ordered structure with 12.2% $\alpha$-helix, 30.7%$\beta$-sheet, 18.5% $\delta$-turn, and 38.5% random coil. The optimum pH and temperature of the enzyme activity were pH 9.3 and 27$^{\circ}C$. The enzyme exhibited the highest affinity and catalytical efficiency to phospholipid hydroperoxide employing GSH or Trx as electron donor. Moreover, the protein displayed higher GSH-dependent activity towards t-Butyl-OOH and $H_2O_2$. These results show that OsPHGPx is an enzyme with broad specificity for hydroperoxide substrates and yielded significant insight into the physicochemical properties and the dynamics of OsPHGPx.

• Journal of Environmental Health Sciences
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• v.43 no.5
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• pp.393-400
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• 2017

This study was investigated on pH, heavy metals, oils and solvents in 34 surface soil samples and the samples are collected at two times for 17 farmland sites around 7 industrial areas in Northern Gyeonggi Province. As a result of pH for soil contamination monitoring network, the range of pH showed 4.4~8.4 and average was 6.3. The range of pH for Agricultural land around industrial area was 6.7~7.5 and average indicated 7.1 that mostly showed neutral condition in this area. he average concentrations of Cu, Pb, Ni, As and $Cr^{6+}$ are lower than Korea soil contamination worrisome levels at region 1 and the mean levels of farmland from the soil quality monitoring network. The average concentrations of Zn, Cd and Hg didn't exceed the soil contamination worrisome levels at region 1 but slightly higher than the mean levels of farmland from the soil quality monitoring network. The heavy metal levels of all samples are within Korea soil contamination worrisome levels at region 1. The results showed that the detected heavy metal concentrations ranged from N.D. to ~32.7% of Korea soil contamination worrisome levels at region 1. BTEX, TPH, TCE and PCE were not detected in all samples and thus the farmland around the industrial areas were free from oils and solvents contamination.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1085-1088
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• 2011

Heavy metal concentration as well as chemical composition were surveyed in commercial liquid pig manure to provide the basic information for mitigation research of hazardous material to agro-product. Seventy-five samples of liquid pig manure were collected and analyzed from 2009 to 2010 nationwide. Average contents of T-N, $P_2O_5$, and $K_2O$ were 0.29%, 0.08%, and 0.11%, respectively. The contents of heavy metals ranged from 0.001~0.083 for As, 0.001~0.108 for Cd, 0.002~0.495 for Cr, 0.07~47.8 for Cu, ND~0.005 for Hg, 0.035~1.033 for Ni, ND~0.291 for Pb, and $0.75{\sim}342.4mg\;L^{-1}$ for Zn, respectively. It was noted that among 75 samples, only four samples exceeded the Zn guideline ($130mg\;L^{-1}$) of liquid fertilizer derived from livestock manure but others were not exceeded the regulation.

• Journal of Microbiology and Biotechnology
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• v.29 no.9
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• pp.1444-1452
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• 2019

The conventional prophylactic vaccines for human papillomavirus (HPV) efficiently prevent infection with high-risk HPV types, but they do not promote therapeutic effects against cervical cancer. Previously, we developed HPV16 E7-expressing Lactobacillus casei (L. casei-E7) as a therapeutic vaccine candidate for cervical cancer, which induces antitumor therapeutic effects in a TC-1 murine cancer model. To improve the therapeutic effect of L. casei-E7, we performed co-treatment with poly-gamma-glutamic acid (${\gamma}-PGA$), a safe and edible biomaterial naturally secreted by Bacillus subtilis. We investigated their synergistic effect to improve antitumor efficacy in a murine cancer model. The treatment with ${\gamma}-PGA$ did not show in vitro cytotoxicity against TC-1 tumor cells; however, an enhanced innate immune response including activation of dendritic cells was observed. Mice co-administered with ${\gamma}-PGA$ and L. casei-E7 showed significantly suppressed growth of TC-1 tumor cells and an increased survival rate in TC-1 mouse models compared to those of mice vaccinated with L. casei-E7 alone. The administration of ${\gamma}-PGA$ markedly enhanced the activation of natural killer (NK) cells but did not increase the E7-specific cytolytic activity of $CD8^+$ T lymphocytes in mice vaccinated with L. casei-E7. Overall, our results suggest that oral administration of ${\gamma}-PGA$ induces a synergistic antitumor effect in combination with L. casei-E7.