• Journal of Microbiology and Biotechnology
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• v.23 no.3
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• pp.430-435
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• 2013

Multidrug resistance, especially multidrug efflux mechanisms that extrude structurally unrelated cytotoxic compounds from the cell by multidrug transporters, is a serious problem and one of the main reasons for the failure of therapeutic treatment of infections by pathogenic microorganisms as well as of cancer cells. Streptococcus mutans is considered one of the primary causative agents of dental caries and periodontal disease, which comprise the most common oral diseases. A fragment of chromosomal DNA from S. mutans KCTC3065 was cloned using Escherichia coli KAM32 as host cells lacking major multidrug efflux pumps. Although E. coli KAM32 cells were very sensitive to many antimicrobial agents, the transformed cells harboring a recombinant plasmid became resistant to several structurally unrelated antimicrobial agents such as tetracycline, kanamycin, rhodamin 6G, ampicillin, acriflavine, ethidium bromide, and tetraphenylphosphonium chloride. This suggested that the cloned DNA fragment carries a gene encoding a multidrug efflux pump. Among 49 of the multidrug-resistant transformants, we report the functional gene cloning and characterization of the function of one multidrug efflux pump, namely MdeA from S. mutans, which was expressed in E. coli KAM32. Judging from the structural and biochemical properties, we concluded that MdeA is the first cloned and characterized multidrug efflux pump using the proton motive force as the energy for efflux drugs.

• Restorative Dentistry and Endodontics
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• v.41 no.4
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• pp.283-295
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• 2016

Objectives: In this study, we characterized human dental pulp cells (HDPCs) obtained by different culture methods to establish the most suitable methodology for dental tissue engineering and regenerative endodontic applications. Materials and Methods: HDPCs were isolated by the outgrowth method (HDPCs-OG), the enzymatic digestion method (collagenase/dispase/trypsin, HDPCs-ED), or the combination of both methods (HDPCs-Combined). The expression of mesenchymal stem cell markers (CD105, CD90, and CD73) was investigated. In vitro differentiation capacities of HDPCs into adipogenic, osteogenic, and chondrogenic lineages were compared. Differentiation markers were analyzed by quantitative reverse-transcription polymerase chain reaction (RT-PCR) and western blotting. Results: Our data indicated that whole HDPCs-ED, HPDCs-OG, and HDPCs-Combined could be differentiated into adipogenic, chrondrogenic, and osteogenic cell types. However, we found that the methods for isolating and culturing HDPCs influence the differentiation capacities of cells. HDPCs-OG and HDPCs-ED were preferably differentiated into adipogenic and osteogenic cells, respectively. Differentiation markers shown by RT-PCR and western blotting analysis were mostly upregulated in the treated groups compared with the control groups. Conclusions: Our findings confirmed that cell populations formed by two different culture methods and the combined culture method exhibited different properties. The results of this study could provide an insight into regenerative endodontic treatment using HDPCs.

• Archives of Craniofacial Surgery
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• v.21 no.3
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• pp.161-165
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• 2020

Background: Microstomia is defined as a condition with a small sized-mouth that results in functional impairment such as difficulty with food intake, pronunciation, and poor oral hygiene and cosmetic problems. Several treatment methods for microstomia have been proposed. None of them are universally applicable. This study aims at analyzing the cases treated at our institution critically reviewing the pertinent literature. Methods: The medical records of all microstomia patients treated in our hospital from November 2015 to April 2018 were reviewed retrospectively. Of these, all patients who received surgical treatment for microstomia were included in the study and analyzed for etiology, chief complaint, surgical method, and outcomes. The functional outcomes of mouth opening and intercommissure distance before and after the surgery were evaluated. The cosmetic results were assessed according to the patients' satisfaction. Results: Five patients with microstomia were corrected. Two cases were due to scar contracture after chemical burn, two cases derived from repeated excision of skin cancer, and one patient suffered sequela of Stevens-Johnson syndrome. The following surgical methods were applied: one full-thickness skin graft on the buccal mucosa, three buccal mucosal advancement flaps after triangular excision of the mouth corner, and one local buccal mucosal flap. Mouth opening was increased by 6.0 mm, and the intercommissure distance improved by 7.2 mm on average. Follow-up was 9.6 months (range, 5-14 months). Cosmetic assessment was as follows: two patients found the results excellent, three judged it as good. Conclusion: Microstomia has several causes. In order to achieve optimal functional recovery and aesthetic improvement it is important to precisely evaluate the etiologic factors and the severity of the impairment and to carefully choose the appropriate surgical method.

• BMB Reports
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• v.38 no.3
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• pp.300-306
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• 2005

Tamoxifen citrate is an anti-estrogenic drug used for the treatment of breast cancer. It showed a degree of hepatic carcinogenesis, when it used for long term as it can decrease the hexose monophosphate shunt and thereby increasing the incidence of oxidative stress in liver rat cells leading to liver injury. In this study, a model of liver injury in female rats was done by intraperitoneal injection of tamoxifen in a dose of 45 mg/kg body weight for 7 successive days. This model produced a state of oxidative stress accompanied with liver injury as noticed by significant declines in the antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase and catalase) and reduced glutathione concomitant with significant elevations in TBARS (thiobarbituric acid reactive substance) and liver transaminases; sGPT (serum glutamate pyruvate transaminase) and sGOT (serum glutamate oxaloacetate transaminase) levels. The oral administration of dimethyl dimethoxy biphenyl dicarboxylate (DDB) in a dose of 200 mg/kg body weight daily for 10 successive days, resulted in alleviation of the oxidative stress status of tamoxifen-intoxicated liver injury in rats as observed by significant increments in the antioxidant enzymes (glutathione-S-transferase, glutathione peroxidase and catalase) and reduced glutathione concomitant with significant decrements in TBARS and liver transaminases; sGPT and sGOT levels. The administration of DDB before tamoxifen intoxication (as protection) is more little effective than its curative effect against tamoxifen-induced liver injury. The data obtained from this study speculated that DDB can mediate its biochemical effects through the enhancement of the antioxidant enzyme activities and reduced glutathione level as well as decreasing lipid peroxides.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.482-488
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• 2013

Two piperazine-containing 3,4-dihyroquinazolines (BK10007S/8S) have been synthesized, based on our previous work on the synthesis and antitumoral activity of 3,4-dihyroquinazolines. After evaluating them for T-type calcium channel blocking effect and in vitro anti-cancer effect, they were profiled for acute and repeat dose toxicity (40 mg/kg, 2 weeks) to BALB/c mice. BK10007S/8S were further in vivo evaluated against human pancreatic MIA PaCa-2 carcinoma in $BALB/c^{nu/nu}$ nude mice, which exhibited 54 and 61% tumor growth inhibition through 57-day oral administration of 2 mg/kg of body weight, respectively.

• Development and Reproduction
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• v.21 no.4
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• pp.441-448
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• 2017

Bisphenol-A(BPA) is a member of alkylphenol family, and shows adverse effects including reduced fertility, reproductive tract abnormalities, metabolic disorder, cancer induction, neurotoxicity and immunotoxicity. In the present study, we conducted Hershberger assay to evaluate whether the two candidates to replace BPA have androgenic or antiandrogenic activity. The assay was carried out using immature castrated Sprague-Dawley male rats. After 7 days of the surgery, testosterone propionate (TP, 0.4 mg/kg/day) and test materials (low dose, 40 mg/kg/day; high dose, 400 mg/kg/day) were administered for 10 consecutive days by subcutaneous (s.c.) injection and oral gavage, respectively. Test materials were BPA, isosorbide (ISO) and cyclohexanedimethanol (CHDM). The rats were necropsied, and then the weights of five androgen-dependent tissues [ventral prostate, seminal vesicle, levator ani-bulbocavernosus (LABC) muscle, paired Cowper's glands, and glans penis] and three androgen-insensitive tissues (kidney, spleen and liver) were measured. All test materials including BPA did not exhibit any androgenic activity in the assay. On the contrary, antiandrogen-like activities were found in all test groups, and the order of the intensity was CHDM > BPA > ISO in the five androgen-sensitive tissues. There was no statistical difference between low dose treatment and high dose treatment of BPA group as well as ISO group. In CHDM group, high dose treatment exhibited most severe weight reduction in all measured tissues. There was no statistical difference in androgen-insensitive tissue measurements, except BPA groups. Since the effects of ISO treatment on the accessory sex organs were much less or not present at all when compared to those of BPA, ISO could be a strong candidate to replace BPA. CHDM treatment brought most severe weight reduction in all of androgen-sensitive tissues, so this material should be excluded for further screening of BPA substitute selection.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1507-1515
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• 2006

Angelica gigantis (AG), Rehamaninae Radix(RR), Paenia japonica (PJ), and Polygoni multiflori Radix (PM) have been used as medicinal plants to tonify the blood. General function of the drugs have been known to nourish blood and control the heart and liver meridians. Recently, several studies have proposed mechanisms by which some oriental medicinal herbs work on the immune system. However, it is uncertain whether aqueous-extract of these drugs has immunomodulatory effect yet. In this study, I investigated the immune promotive effects of the water-extracted AG, RR, PJ and PM. The water-extracted AG, RR, PJ and PM inhibited NO production and iNOS expression in LPS stimulated RAW 264.7 macrophage cell line. Among these extracts, AG and PM induced expression of IL-2 and IFN${\gamma}$ in mouse spleen cells. In the flow cytometry analysis, PM-stimulated mouse spleen cells showed an increase in B-cell phenotype (CD45R/B220). The oral administration of Polygoni multiflori water-extracts to mice having S-180 abdominal dropsy cancer prolonged life-span more than control mice. These data suggest that among these extracts, PM has cellular and humoral immune-enhancement effect through IL-2 and IFN${\gamma}$ cytokine production, the regulation of NO production in macrophage cells and the B cell production in spleen cells.

• Toxicological Research
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• v.21 no.3
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• pp.235-240
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• 2005

Pollen has been used for prevention or treatment of certain diseases such as diabetes arthritis or cancer in traditional medicine. Among various pollens, pine tree pollen is known to relieve hypertension, suppress fatty liver progression, and facilitate the digestion, but its immunological activities are less known. To evaluate immunological reactivities and immunotoxicities of pine tree pollen, BALB/c mice were administered to the poller through oral route. Pine tree pollen suspended in distilled water or extracted with methanol has been administered at the concentration of 0, 10, or 100 mg/kg five days per week for four weeks. Polyclonal activation of splenic T cells with phytohemagglutinins did not induce a significant difference in IL-4 and $IFN_{\gamma}$ production between the pollen-administered mice groups and the control mice. Furthermore, polyclonal activation of splenic B cells with lipopolysaccharides did not result a significant difference in IgG1 and IgG2a production among the groups. These findings imply that the intake of pine tree pollen does not bring any humoral and cellular immune-dysrequlation. Whereas, viability of Listeria monocytogenes was suppressed in the mice administered with 100 mg/kg bw methanol extract, indicating the potential ability of pine tree pollen to enhance cell-mediated immunity mediated by type-1 helper T cells. In addition, aberrant upregulation of plasma IgG1 level was observed in the pollen-administered mice, which suggests a possibility of allergic response induction through the pine tree pollen uptake. Overall, pine tree pollen-mediated modulation of humoral or cellular immunity is worthy of further systematic investigation.

• Mass Spectrometry Letters
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• v.8 no.2
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• pp.23-28
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• 2017

Arctigenin is the main active ingredient of Fructus Arctii, which has been reported with a variety of therapeutic activities including anti-cancer, anti-inflammation, anti-virus, and anti-obesity effects. In this study, a simple and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of arctigenin in rat plasma. The assay utilized a simple protein precipitation with methanol and the mobile phase consisted of 100% methanol and water containing 0.1% formic acid (65:35 v/v). Arctigenin and the internal standard (psoralen) were monitored using a positive electrospray turbo ionspray mode with multiple reaction monitoring transitions of m/z $373.2{\rightarrow}136.9$ and m/z $187.2{\rightarrow}130.9$, respectively, and total chromatographic run time was within 5 min. The lower limit of quantification (LLOQ) of arctigenin was 5 ng/mL in the rat plasma. The intra- and inter-day accuracy of arctigenin at LLOQ and matrix-matched quality control samples ranged 97.4 - 104.8% and 97.2 - 102.0%, respectively. The intra-day precision was within 4.80% and the inter-day precision was within 5.92%. Application of the present method was demonstrated through a pharmacokinetic study after intravenous and oral administration of arctigenin in male Sprague Dawley rats.

• Journal of dental hygiene science
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• v.9 no.5
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• pp.539-543
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• 2009

This study lays its purpose on finding general trends in dental fear among adolescences at 15~17 years of age, differences in levels of dental fear according to temperament, and their causal relationships. The researcher made use of a questionnaire including tools questionnaire of survey - DFS, EAS - and then analyzed covariate structure modeling by using LISREL 8.12 after conducting univariate analysis by employing SPSS. Cronbach's reliability coefficients showed higher in DFS(0.957), EAS(0.916), and GFS (0.910), and females rather than males showed higher levels of dental fear, and of types of traits, trait III showed lower levels of dental fear than the others, and also the less perceived dental health status and the more recent experience in pain when treating dental disease and also the more broken dental appointments, the higher levels of dental fear showed with statistical significance. In addition, there showed a positive correlation between fear of dental treatment, a distrust of dentists, and a general feeling of fear.