• 대한수의학회지
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• 제58권3호
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• pp.153-158
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• 2018

Althaea rosea has been used in traditional Chinese medicine to treat numerous diseases, but no studies have investigated its anti-influenza properties to date. In this study, we investigated the anti-influenza effects of Althaea rosea. BALB/c mice orally pretreated with Althaea rosea ($200{\mu}L$, 0.1 mg/mL concentration in phosphate-buffered saline) and followed by infection of influenza A virus nasally showed higher survivability and lower lung virus titer against divergent subtypes of influenza A virus infection. We also found that oral administration of Althaea rosea elicited antiviral innate immune responses in serum, bronchoalveolar lavage fluid, small intestinal fluid, and the lungs. Taken together, these findings suggest that aqueous extracts of Althaea rosea are a potential candidate for use as an anti-influenza drug.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.143-147
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• 2005

The non-pathogenic, non-glycopeptide-producing actinomycete Streptomyces coelicolor carries a cluster of seven genes (vanSRJKHAX) that confers inducible, high-level resistance to vancomycin. The van genes are organised into four transcription units, vanRS, vanJ, vanK and vanHAX, and these transcripts are induced by vancomycin in a vanR-dependent manner. vanHAX are orthologuous to genes found in vancomycin resistant enterococci that encode enzymes predicted to reprogramme peptidoglycan biosynthesis such that cell wall precursors terminate in D-Ala-D-Lac, rather than D-Ala-D-Ala. vanR and vanS encode a two-component signal transduction system that mediates transcriptional induction of the seven van genes. vanJ and vanK are novel genes that have no counterpart in previously characterised vancomycin-resistance clusters from pathogens. VanK is essential for vancomycin resistance in S. coelicolor and it is required for adding Gly branch to stem peptides terminating D-Ala-D-Lac. Because VanK can recognise D-Lac-containing precursors but the constitutively expressed femX enzyme, encoded elsewhere on the chromosome, cannot recognize D-Lac-containing precursors as a substrate, vancomycin-induced expression of VanHAX in a vanK mutant is lethal. Further, femX null mutants are viable in the presence of glycopeptide antibiotics but die in their absence. Bioassay using vanJp-neo fusion reporter system also showed that all identified inducers for van genes expression were glycopeptide antibiotics, but teicoplanin, a membrane-anchored glycopeptide, failed to act as an inducer.

• Biomolecules & Therapeutics
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• 제18권4호
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• pp.396-401
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• 2010

We conducted this study to investigate whether baicalin, baicalein or schizandrin significantly affect MUC5AC mucin production induced by epidermal growth factor (EGF) or phorbol ester (PMA) in human airway epithelial cells. Confluent NCI-H292 cells were pretreated with varying concentrations of baicalin, baicalein or schizandrin for 30 min and then stimulated with EGF or PMA for 24 h, respectively. MUC5AC mucin protein production was measured by ELISA. The results were as follows: (1) Baicalin was found to inhibit the production of MUC5AC mucin protein induced by both EGF and PMA. (2) Baicalein, the aglycone of baicalin, also inhibited MUC5AC mucin production. (3) Schizandrin, derived from Schizandrae Fructus, inhibited MUC5AC mucin production by the same inducers. These results suggest that baicalin, baicalein and schizandrin can regulate the production of mucin protein by directly acting on human airway epithelial cells.

• Biomolecules & Therapeutics
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• 제19권3호
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• pp.320-323
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• 2011

We conducted this study to investigate whether berberine signifi cantly affects MUC5AC mucin gene expression and mucin production induced by epidermal growth factor (EGF), phorbol 12-myristate 13-acetate (PMA) or tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) from human airway epithelial cells. Confl uent NCI-H292 cells were pretreated with varying concentrations of berberine for 30 min and then stimulated with EGF, PMA or TNF-${\alpha}$ for 24 h. MUC5AC mucin gene expression and mucin production were measured by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Berberine was found to inhibit the expression of MUC5AC mucin gene induced by EGF, PMA or TNF-${\alpha}$. Berberine also inhibited the production of MUC5AC mucin protein stimulated by the same inducers. This result suggests that berberine can regulate the expression of mucin gene and production of mucin protein, by directly acting on human airway epithelial cells.

• 생약학회지
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• 제32권4호통권127호
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• pp.269-273
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• 2001

Ethanol extracts from Xanthii Fructus (XFE) and Prunellae Spica (PSE) were investigated for the effects on the induction of cancer chemoprevention-associated enzymes. The following effects were measured: (a) induction of quinone reductase (QR) (b) induction of glutathione S-transferase (GST) (c) reduced glutathione (GSH) level. XFE and PSE were potent inducers of quinone reductase activity in Hepa1c1c7 murine hepatoma cells. Glutathione levels were increased with XFE and PSE. In addition, glutathione S-transferase activity was increased with XFE. However, GST activity was not increased with PSE. These results suggest that XFE and PSE have chemopreventive potentials by inducing quinone reductase and increasing GSH levels.

• Toxicological Research
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• 제17권
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• pp.83-88
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• 2001

Most reactive oxygen species (ROS) are free radicals and implicated in the development of a number of disease processes including artherosclerosis, neurodegenerative disorders, aging and cancer. ROS are byproducts of a number of in vivo metabolic processes and are formed deliberately as part of nor-mal inflammatory response. On the other hand, ROS are generated either as by products of oxygen reduction during xenobiotic metabolism or are liberated as the result of the futile redox cycling of the chemical agents including several chemical carcinogens. A better understanding of the mechanisms of free radical toxicity may yield valuable clue to risks associated with chemical exposures that leading to the development of chronic diseases including cancer. The molecular biology of ROS-mediated alterations in gene expression, signal transduction and carcinognesis is one of the important subjects in free radical toxicology. Epidemiological studies suggest that high intake of vegetables and fruits are associated with the low incidence of human cancer. Many phytopolyphenols such as tea polyphenols, curcumin, resveratrol, apigenin, genistein and other flavonoids have been shown to be cancer chemopreventive agents. Most of these compounds are strong antioxidant and ROS scavengers in vitro and effective inducers of antioxidant enzymes such as superoxide dismutatse, catalase and glutathione peroxidase in vivo. Several cellular transducers namely receptor tyrosine kinase, protein kinase C, MAPK, PI3K, c-jun, c-fos, c-myc, NFkB, IkB kinase, iNOS, COX-2, Bcl-2, Bax, etc have been shown to be actively modulated by phyto-polyphenols. Recent development in free radical toxicology have provided strong basis for understanding the action mechanisms of cancer chemoprevention.

• Journal of Microbiology and Biotechnology
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• 제5권2호
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• pp.80-86
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• 1995

The bacterial strain WC-17 able to produce chitinase was isolated from soil using an enrichment technique. The isolated strain was identified as Acinetobacter sp. judging by their morphological and physiological characterisitics. The optimal culture conditions for the production of chitinase of Acinetobacter sp. WC -17 are 1.5% colloidal chitin and 1 % tryptone at $30^{\circ}C$ with pH 6.5. Since the enzyme was rapidly produced in a culture supplied with chitin, glucose, or N-acetylglucosamine but not with other polymers and monosaccharide, the enzyme was considered to be an inducible enzyme. Notably N- acetylglucosamine and glucose were found to be effective inducers at low concentrations but repressors at excessive concentrations. The cultural supernatant of Acinetobacter sp. WC-17 inhibited the growth of phytopathogenic fungi such as P.oryzae, R.solani, and F.solani. Among the phytopathogenic fungi tested, P.oryzae was the most sensitive. The conventional agar plate (PDA containing 1 % colloidal chitin) method also produced the same result.

• Journal of Microbiology and Biotechnology
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• 제14권6호
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• pp.1333-1337
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• 2004

Oxidants such as hydrogen peroxide are powerful inducers of cell damage, ageing, and apoptosis. Since clusterin, a 75-80 kDa mammalian glycoprotein, is frequently found to be inducible in apoptotic cells and tissues, this study inquired into whether this would be a protective mechanism against further cell death. The aim was to find out whether overexpression of clusterin could protect cells from oxidant­induced stress and apoptosis. To clarify this issue, we generated and analyzed stable cell lines expressing fusion proteins of a rat clusterin with an enhanced green fluorescent protein (EGFP). When treated with varying concentrations of hydrogen peroxides, clusterin transfectants indeed showed increased resistance to apoptosis and exhibited a much higher survival rate than mock-transfected cells. On the other hand, neither intracellular re-distribution nor local concentration of clusterin-EGFP was observed, which leaves the question open about its anti-apoptotic mechanism. In conclusion, the overexpression of clusterin provides a means for protecting cells against oxidative stress and subsequent cell death.

• Journal of Microbiology and Biotechnology
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• 제16권7호
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• pp.1026-1031
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• 2006

The optimization of the production of a fusion protein containing the antigenic domain 1 (AD-1) is of a great importance, considering its use in diagnostic tests. The fusion protein is produced by the fermentation of a recombinant strain of Escherichia coli containing the plasmid Mbg58, which expresses the AD-1 (aa 484-650) of human cytomegalovirus glycoprotein B as a fusion protein together with aa 1-375 of ${\beta}-galactosidase$. An important characteristic of promoters (lac and derivatives) used in recombinant protein production in E. coli is their inducibility. Induction by IPTG is widely used for basic research; however, its use in large-scale production is undesirable because of its high cost and toxicity. In this work, studies using different inducers and carbon sources for the production of a fusion protein containing the AD-l were performed. The results showed that lactose could be used as an inducer in the fermentation process for the production of this protein, and that expression levels could exceed those achieved with IPTG. The use of lactose for protein expression in E. coli should be extremely useful for the inexpensive, large-scale production of heterologous proteins in E. coli. Addition of sucrose to the fermentation medium improved the yield of recombinant protein, whereas addition of fructose or trehalose decreased the yield.

• Journal of Microbiology and Biotechnology
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• 제28권5호
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• pp.748-756
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• 2018

Biofilms are of vital significance in bioconversion and biotechnological processes. In this work, sugarcane molasses was used to enhance biofilms for the improvement of the production of fumigaclavine C (FC), a conidiation-associated ergot alkaloid with strong anti-inflammatory activities. Biofilm formation was more greatly induced by the addition of molasses than the addition of other reported biofilm inducers. With the optimal molasses concentration (400 g/l), the biofilm biomass was 6-fold higher than that with sucrose, and FC and conidia production was increased by 5.8- and 3.1-fold, respectively. Moreover, the global secondary metabolism regulatory gene laeA, FC biosynthetic gene fgaOx3, and asexual central regulatory genes brlA and wetA were upregulated in molasses-based biofilms, suggesting the upregulation of both asexual development and FC biosynthesis. This study provides novel insight into the stimulatory effects of molasses on biofilm formation and supports the widespread application of molasses as an inexpensive raw material and effective inducer for biofilm production.