• Korean Journal of Microbiology
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• v.17 no.1
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• pp.25-41
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• 1979

A strain able to grow up m-toluate minimal medium has been isolated after selective enrichment and given the name T81X, which was later identified as pseudomonase putida according to its morphological and biochemical characteristics. After treatment with plasmied specific curing agent, mitomycin C, followed by replica plating on m-toluate and xylene minimal agar plate, T81Xstrain has been shown to harbour a curable plasmid relating to the m-toluate and xylene metabolism. Spontaneous curing frquency of this plasmid was also greatly enhanced by growing on benzoate minimal medium. After then, it was also xylene metabogrowing on benzoate minimal medium. After then, it was found to be conjugally nontransmissible. From the comparative investigation of catechol 1,2-oxygenase and catechol 2,3-oxygenase activities in wild type and cured strain on various growth substrate, it appeared that T81X strain has both of these two enzymes while cured strain has catechol 1,2-oxygenase only. Growing on m-toluate minimal medium T81X strain should carry the genetic information necessary for coding the catechol 1,2-oxygense induced by m-toluate or benzoate, on that curable plasmid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.2
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• pp.359-365
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• 1998

This study was carried out to investigate mutagenecity and antimutagenic effects from crude extract, heating extract and alcohol extract of Korean mistletoe(Viscum album L.) on the bacterial short-term tests, such as Ames test, spore rec-assay, SOS spot test and SOS chromotest by using several kinds of mutagens. In the Ames test, each extract did not show any mutagenesis, but each extract showed inhibitory effects of 80∼95% and 70∼94% against mutagenesis induced by 3-amino-1, 4-dimethyl-5H-pyrido[4,3-b] indole(Trp-P-1) and 2-aminofluorene(2-AF) in Salmonella typhimurium TA98, respectively. In th spore rec-assay, mistletoe ectracts showed antimutagenic effect with inhibiton zone in the range of 5∼11mm against mutagenicity induced by mitomycin C(MMC, 18mm) and N-methyl-N'-nitro-N-nitrosoguanidne (MNNG, 24mm), respectively. The heating and alcohol extracts in the SOS chromotest showed 96% and 70% inhibition against benzo-α-pyrene[B(α)P] and Trp-P-1 induced mutagenesis, respectively.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.516-521
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• 2006

The use of gltA gene, as a new biomarker for environmental stress biomonitoring, was investigated because of its key position as the first enzyme of the tricarboxylic acid (TCA) cycle. A recombinant bioluminescent Escherichia coli strain, EBJM2, was constructed using a plasmid carrying the citrate synthase (gltA) promoter transcribing the Photorhabdus luminescens IuxCDABE genes (gltA::luxCDABE). The responses from this strain were studied with five different classes of toxicants: DNA damage chemicals, phenolics, oxidative-stress chemicals, PAHs, and organic solvents. EBJM2 responded strongly to DNA damage chemicals, such as mitomycin C (MMC) and methyl-nitro-nitrosoguanidine (MNNG) and nalidixic acid with the strongest responses. In contrast, tests with several compounds from the other four classes of toxicants gave no significant response. Therefore, EBJM2 was found to be sensitive to DNA damage chemicals.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.67-72
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• 1986

Aromatic hydrocarbon degrading bacteria were isolated from industrial waste by using an agar plate method. The isolate DY-1 was identified as Acinetobacter sp. and found to utilize phenanthrene as tis sole carbon source. THe bacteria were proved to produce salicylic acid as an intermediate from phenanthrene through naphthalene pathway, when the products in the culture were wxamined by thin-layer chromatography. THe $Phn^+$ genes were found to be involved in two plasmids of about 4 and 40kb which were lost and not detected in the DNA samples prepared from the mitomycin C-cured cells by a gel electrophoretic analysis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.5
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• pp.1290-1294
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• 2006

Biflavonoid (1) showed no antimicrobial activity at a concentration of 150 ${\mu}$g/disc. However, the crude extract of Quintinia acutifolia Kirk inhibited the growth of Bacillus subtilis and the dermatophytic fungus Trichophyton mentagrophytes. 2',3'-Dihydroochanaflavone (1) showed some cytotoxicity with IC$_{50}$ value of 3.1 ${\mu}$g/mL against P388 murine lymphocytic leukemia cells (positive control: mitomycin C IC$_{50}$ 0.06 ${\mu}$g/mL). The structure was determined by Spectroscopic methods.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.20 no.4
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• pp.211-215
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• 2017

Esophageal strictures are seldom in children. In many countries, accidental ingestion of corrosives is a major cause of risk for stricture formation. Therefore, their management is a challenge. Safety and long-term efficacy of esophageal dilation for benign esophageal strictures has been confirmed in children. Because most children with structures are toddlers or younger, balloon dilatation is often preferred over bouginage. There is increasing evidence that short duration administration of high doses steroids may be of benefit in some specific situation (IIb esophagitis according to Zargar classification). Mytomycin-C application needs to be further evaluated. Stenting was reported to be successful in some refractory cases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.881-887
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• 2000

The antimutagenic effects of persimmon leaf tea extract (PLTE) at concentration levels consumed by human were examined in mice using micronuleus induction with MMC(mitomycin C) or 4-NQO (4-nitroquinoline-1-oxide). When mice received oral gavage of 10 equivalent to PLTE 24 hr and 6 hr before, and 5 equivalent to PLTE 6 hr before and 3 hr after intraperitoneal injection of MMC, a significant decrease in the frequency of micronuclei were observed. The induction of micronuclei by 4-NQO was suppressed by oral dosage of PLTE at 5 equivalent to PLTE 6 hr before and 3 hr after, 10 equivalent to PLTE 3 hr before and 3 hr after intraperitoneal injection of MMC. Though the components of PLTE have not been analyzed so far, our present results suggest the existence of several bio-antimutagens and/or desmutagens in PLTE, beside catechin, well-known antimutagen.

• International Journal of Oral Biology
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• v.47 no.2
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• pp.17-24
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• 2022

Preserving intact genetic material and delivering it to the next generation are the most significant tasks of living organisms. The integrity of DNA sequences is under constant threat from endogenous and exogenous factors. The accumulation of damaged or incompletely-repaired DNA can cause serious problems in cells, including cell death or cancer development. Various DNA damage detection systems and repair mechanisms have evolved at the cellular level. Although the mechanisms of these responses have been extensively studied, the global RNA expression profiles associated with genomic instability are not well-known. To detect global gene expression changes under different DNA damage and hypoxic conditions, we performed RNA-seq after treating human cervical cancer cells with ionizing radiation (IR), hydroxyurea, mitomycin C (MMC), or 1% O₂ (hypoxia). Results showed that the expression of 184-1037 genes was altered by each stimulus. We found that the expression of 51 genes changed under IR, MMC, and hypoxia. These findings revealed damage-specific genes that varied differently according to each stimulus and common genes that are universally altered in genetic instability.

• Korean Journal of Veterinary Research
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• v.33 no.4
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• pp.701-710
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• 1993

The pine needles, Pinus densiflow Sieb. et Zucc., which is a feed for goats showing a low incidence rate of cancer were evaluated to confirm the potent anticancer effects, with or without several conventional anticancer drugs. The pine needles collected from Mt. Buk-Han located near Seoul were extracted with 95% methanol and methand and concentrated. From the methanol extract, SOM-A, was extracted dichlormethane and SOM-B was extracted with ethyl acetate. SOM-C was extracted with distilled water. These extracts were tested for their antitumor activities in vitro and in vivo. Among them, SOM-A and SOM-C exhibited potent antitumor activities described as belows. 1. The cytotoxic effects of SOM-A and SOM-C were examined against in vitro cultured murine and humman tumor cells. SOM-A showed strong cytotoxicity against human tumor cell lines and SOM-C showed strong cytotoxicity against murine tumor cell lines tested. 2. The antitumor effects of SOM-A and SOM-C were examined against P388 and L1210 of mouse ascitic tumors. The highest mean survival time(MST) ration was 151%(P388) for SOM-C(90mg/kg). 3. To compare the antitumor effects of SOM-A, SOM-B, and SOM-C against solid tumors, S-180 and Ehrlich carcinoma were implanted subcutaneously to mice on Day O. The drugs were given intraperitoneally to mice once a day on Days 1-20, and the tumor weights were measured on Day 21. SOM-A showed inhibition of tumor growth more than 50% in the experiment on S-180 and Ehrlich, and SOM-C also markedly inhibited tumor growth. However, SOM-B had no effect. 4. SOM-C combined with ${\alpha}$-interferon and SOM-C combined with Mitomycin-C enhanced the antitumor activities against murine ascitic tumors P388 leukemia.

• The Journal of Internal Korean Medicine
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• v.18 no.1
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• pp.48-61
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• 1997

In this study, antineoplastic activity against human hepatocellular carcinoma cell line(Hep G2) was tested in Gleditsiae Spina. Gleditsiae Spina was extracted with water, and the cytotoxic activity was tested using a calorimetric tetrazolium assay(MTT assay), the apoptosis was tested using a DNA electrophoresis and flow cytometry. The nitric oxide production from mouse peritoneal macrophage was tested using a Griess method. Gleditsiae Spina extracts against the proliferation of Hep G2 cells not showed cytotoxicity at the concentration of less than $100{\mu}g/ml$, and Gleditsiae Spina extracts not showed the cytotoxicity of mitomycin C and the cytotoxicity of cisplatin on Hep G2 cells. Gleditsiae Spina extracts aginist the proliperation of BALB/c 3T3 cells not showed cytotoxicity, the proliperation of mouse thymocytes and splenocytes not showed cytotoxicity at the concentration of less than $100{\mu}g/ml$. Gleditsiae Spina extracts not showed nitric oxide production from mouse peritoneal macrophage in vitro. Gleditsiae Spina was administered orally for 7 days at 300mg/kg increased nitric oxide production from mouse peritoneal macrophage.