• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.114-120
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• 1994

To clarify the effect of storage temperature on the morphological and histological changes of plaice, Paralichthys olivaceus muscle at early stages after killing, the changes in breaking strength of muscle, morphological observation of myofibrils and histological observation of extracellular spaces during storage at $0^{\circ}C\;and\;10^{\circ}C$ were studied. The maximum breaking strength of samples stored at $0^{\circ}C$ was reached within 10hrs and then it dropped significantly (p<0.05) from 10hrs to 25hrs of storage. However, breaking strength was not increased in fresh muscle stored at $10^{\circ}C$ and gradually decreased after 10hrs storage. In myofibrils prepared from dorsal muscle immediately after death, A-band, I-band, H-band and Z-line in sarcomere were clearly distinguishable from each other. Due to muscle contraction, it was not easy to distinguish H-band from I-band observed in sarcomere stored at $0^{\circ}C$ after 10hrs storage. But, in the case of samples stored at $10^{\circ}C$, H-band could be observed dimly until 15hrs of storage. The changes in morphological myofibrils were closely related to increase of breaking strength. No extracellular space was observed among muscle cells immediately after killing. Stored samples at $0^{\circ}C$ showed extracellular spaces after 15hrs storage. On the other hand, samples stored at $10^{\circ}C$ didn't show any extracellular spaces until 15hrs storage and showed extracellular spaces after 24hrs storage. It was thought that the post-mortem tenderization of plaice muscle was closely related to the gradually disintegration of the extracellular matrix structure after killing.

• YAKHAK HOEJI
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• v.41 no.2
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• pp.225-232
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• 1997

The in vitro antibacterial activity of DWP20367 (1-Cyclopropyl-6-fluoro-8-chloro-7-(2,7-diazabicyclo[3,3,0]oct-4-ene-7-yl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid), a new broad-spectrum fluoroquinolone, was compared with those of ciprofloxacin (CPFX), sparfloxacin (SPFX) and ofloxacin (OFLX). DWP20367 was showed antibacterial activity much higher than CPFX, SPFX and OFLK against gram-positive bacteria, while it was slightly more superior to quinolones against gram-negative bacteria. DWP20367 was particularly effective against MRSA, and its $MlC_{90}$ against clinical isolates of methicillin-susceptible S. aureus, low methicillin-resistant S. aureus and high methicillin-resistant S. aureus were 0.098, 0.781 and 1.563 micro g/ml, respectively. Against S. pneumoniae, MIC90 of DWP20367 was 2- to 8-fold higher than those of CPFX. With a view of MIC90, DWP20367 showed slightly more potent activity against P. aeruginosa and E. coli isolates than the control quinolones. DWP20367 activity was not affected by inoculum size and medium pH. But addition of $Mg^{2+}, \;Ca^{2+} $Mg2+, Ca2+ or horse serum (25%) decreased its antibacterial activity. DWP20367 was showed rapidly bactericidal activity within 2 to 4 h, and regrowth was not observed even after 24 h incubation at concentrations near the 4-fold of MIC.

• YAKHAK HOEJI
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• v.41 no.2
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• pp.233-240
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• 1997

The in vitro antibacterial activity of DWP20418 (1R, 5S, 6S)-6-[1-(R)-Hydroxyethyl)-l-methyl-2-[(2S,4S)-2-(piperazinylcarbonyl)-1-(R)-hydroxyethyl)pyrrolidine-4-thio]carb apen-2-em-3-carboxylic acid), a new carbapenem antibiotic, was compared with those of imipenem (IPM) and meropenem (MEPM). DWP20418 was comparable or slightly more superior to MEPM against gram-positive bacteria, and it showed more potent activity to IPM against gram-negative bacteria. DWP20418 was particularly active against MRSA, and its $MIC_{90}$ of methicillin-susceptible S. aureus, low methicillin-resistant S. aureus and high methicillin-resistant S. aureus were 0.391, 25 and 50 ${\mu}g/ml$, respectively. With a view of $MIC_{90}$, DWP20418 was comparable than the other carbapenems against P. aeruginosa and E. coli isolates. The activity of DWP20418 was not affected in the presence of $Mg^{2+},\;Ca^{2+}$ or horse serum. But inoculum size and alterations in pH of medium affected its antibacterial activity. DWP20418 showed rapidly bactericidal activity within 1h, and regrowth was not observed even incubation of 24hrs at the concentrations near the MIC.

• Tuberculosis and Respiratory Diseases
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• v.49 no.3
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• pp.298-309
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• 2000

Background : The antitumor effects of herpes simplex virus thymidine kinase (HSV-tk) and ganciclovir (GCV) strategies for cancer gene therapy have a the following advantages : 1) a direct cytotoxicity to HSV-tk modified cancer cells by GCV 2) a cell death by the local transfer of toxic metabolites from the HSV-tk modified cells to nearby unmodified tumor cells (bystander effect), and 3) in vivo bystander effect such as antitumor-immunity. Retroviral and adenoviral sequences can silence transgene expression in cells and mice. In this study, we investigated the above described advantages of HSV-tk/GCV strategy in Lewis lung cell and mouse lung cancer model using retroviral vector and adenoviral vector. Also, we observed whether the expression of a silenced gene can be reactivated by treating cells with butyrate. Methods : Retrovirus-HSV-tk and adenovirus-HSV-tk vectors were used for the transduction of Lewis lung carcinoma (LLC) cells. The change of HSV-tk expression by butyrate was measured by Western blol The antitumor activities containing bystander effect were observed in vivo (by MTT assay) and in vivo tumor models of various combinations of LLC and LLC-tk. Results : 1. Butyrate induced the enhancement of HSV-tk expression from adenovirally transduced cells but not from retrovirally transduced cells. 2. Both retrovirus-HSV-tk and adenovirus-HSV-tk vectors with GCV treatment were effective for killing of tumor cell in vitro and suppression of LLC tumorigenicity. Bystander effect was responsible for killing of mixture of LLC-tk and LLC in vitro and in vivo-tumorigenicity model. Conclusion : Butyrate could augment adenovirus-mediated HSV -tk gene expression. Cancer gene therapy with HSV-tk suicide gene by retroviral and adenoviral vector seems to be an effective approach for lung cancer therapy.

• BMB Reports
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• v.44 no.10
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• pp.669-673
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• 2011

Human methionine sulfoxide reductase B3A (hMsrB3A) is an endoplasmic reticulum (ER) reductase that catalyzes the stereospecific reduction of methionine-R-sulfoxide to methionine in proteins. In this work, we identified an antimicrobial peptide from hMsrB3A protein. The N-terminal ER-targeting signal peptide (amino acids 1-31) conferred an antimicrobial effect in Escherichia coli cells. Sequence and structural analyses showed that the overall positively charged ER signal peptide had an Argand Pro-rich region and a potential hydrophobic ${\alpha}$-helical segment that contains 4 cysteine residues. The potential ${\alpha}$-helical region was essential for the antimicrobial activity within E. coli cells. A synthetic peptide, comprised of 2-26 amino acids of the signal peptide, was effective at killing Gram-negative E. coli, Klebsiella pneumoniae, and Salmonella paratyphi, but had no bactericidal activity against Gram-positive Staphylococcus aureus.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.12
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• pp.2250-2255
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• 2010

An fine silver particle has a variety of uses, such as in killing micrograms and as catalysts. Many techniques have been used for the production of the fine particles. Faraday cell, consisting of two silver electrodes in an electrolyte, is unique, but it is hard to get a very fine particle by this method. A finer silver nano-particle producing cell, utilizing a dielectric bed as a lower electric current and higher field controlling means, has been proposed and investigated. The I-V characteristics of the cell and effect of the dielectric bed on the producing finer silver nano-particles have been investigated. The I-V characteristics of the cell with the dielectric bed were different from that of the same system without the bed, due to the increased cell resistance and elevated electric field intensity. It is found that the proposed cell with the dielectric bed can produce finer silver nano-particles effectively, which, however, can be used as one of effective fine silver nano-particle producing means.

• The Journal of Pediatrics of Korean Medicine
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• v.12 no.1
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• pp.1-39
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• 1998

Recently, Many people begin to be interested in aromatherapy and as the effects of aromatherapy(or essential oils) are being known widely. as aromatherapy is regarded as a new effective method of natural therapy in treatment of human Aromatherapy is defined, 'therapy that methods of inhalation, massage, drink is used, to medical effects, physical effects, psychologic effects.' In this paper, By investigating differences and commons between useful essential oils that are used frequently in children's aroma care and herb medicine, digesting several aromathrapy books and 'Boncho(Herbs)'books, I can obtain such conclusions. 1. Most essential oils mainly can cure skin trobles, psychological troubles. 2. Systemic curing ability of essential oils in human body are urination in reproductive system, sediation in psychological system, sweating in circulation system, anti-inflammation in respiratory system, tonic in digestive system, pain-killing in musclular system, stimulating-immunity in immune system, menstruation in OB & GY3. Herb medicine correspond to essential oils are Chamomile(母:菊: Moguk), Ginger(生畺: Saengang), Frankinsense(乳香: Yuhyang), Eucalyptus(按葉: Anyup), Rosemary(迷迭: Mizil), Rose(薔薇: Jangmi), Sandalwood(檀香: Danhyang), Thyme(麝香草: Sahyangcho) Ylang Ylang(依蘭: Eulan), Lemon(??皮: Ryungmongpi), Madarin(陣皮: Zinpi), Orange(枳殼: Zigak). 4. There are differences of curing ability in human between herb medicine and essential oils because of curing mechanism, but effect on human body are so simular.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.6
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• pp.345-349
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• 2004

Heat shock ($43^{\circ}C$ for 60 minutes) is sufficient to induce apoptosis in a wide number of cell lines. In this study, we asked whether DNA strand breaks are responsible for this phenomenon. Using the highly sensitive comet assay for DNA damage detection, we were unable to demonstrate DNA breaks immediately after heat shock in Raji human Iymphoid cells. It showed that DNA breaks were not necessary for hyperthermic apoptosis, since its activity is indicative of DNA lesions. Here, we present a suggestion that a protein(s) is the major target for heat shock apoptosis. We firstly found glycerol, which reportedly stabilizes protein structure, showed a protective effect in Raji cells against hyperthermic apoptosis. In addition, quercetin, which modulates transcription of the heat shock protein family members, enhanced apoptotic death induced by hyperthermia. Furthermore, Raji cells are protected by a pre-mild heat treatment prior to the killing dose of heat shock.

• Bulletin of Food Technology
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• v.18 no.2
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• pp.99-108
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• 2005

As an alternative to gaseous sanitizer which having penetrating and diffusing capacities, aerosolsanitizer’s effect on killing pathogens was investigated. To test the efficacy of aerosolized sanitizer, peroxyacetic acid was aerosolized($5.42-11.42\mum$) by nebulizer(Royal-G Enterprise, ShenZhen,China) in a model cabinet against artificially inoculated target microorganisms on lettuce. Lettuceleaves were inoculated with a cocktail of three strains each of Escherichia coli O157:H7, Listeriamonocytogenes, and Salmonella Typhimurium and treated with sanitizer aerosol for 10 min, 30 and60 min in a model aerosol cabinet at room temperature($22\pm2^\circC$). After treatment, surviving cellsincluding injured cells were enumerated on appropriate selective agar or using the over-lay agar method, respectively. Inoculated lettuce leaves exposed to antimicrobial aerosol for 10 min experienceda 0.8 log reduction in E. coli O157:H7, a 0.3 log reduction in Salmonella Typhimurium and a 2.5 logreduction in L. monocytogenes when compared to the control. After 30 min treatment, the threepathogens were reduced in number of CFU by 2.2, 3.3, and 2.7-log and after 60 min, the reductions were 3.4, 4.5, and 3.8-log, respectively. Aerosolization can be new antimicrobial agents deliverysystem in food sanitizing.

• Environmental Mutagens and Carcinogens
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• v.9 no.1
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• pp.13-22
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• 1989

The effect of novobiocin (NOV), and inhibitor of topoisomerase II, on ethyl methanesulfonate (EMS)-or bleomycin (BLM)-induced DNA repair synthesis was examined during the cell cycle of Chinese hamster ovary (CHO)-K1 cells. Three assays were employed in this study: cell survival, alkaline elution and unscheduled DNA synthesis. EMS was effective at killing CHO cells in G1 phase, wheras BLM preferentially killed cells in G2 and S phases. EMS induced the much more amount of DNA damage in G1 phase, while BLM induced in G2 phase than the other phases. The both of pre- and post-treatment with BOV inhibitied EMS- or BLM-induced DNA repair synthesis in G1 and G2 phases, and pretreatment with NOV inhibited more effectively than the post-treated group. These results suggested that CHO cells exhibited a differential sensitivity to cell lethality and DNA damage in relation to cell cycle according to used chemical agents, and that DNA topoisomerase II participated in an initial stage of DNA repair.