• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3343-3347
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• 2012

The aim of this study was to investigate the anticlastogenicity as well as the clastogenicity of Eryngium foetidum leaf (EF) using the in vivo mouse peripheral blood erythrocyte micronucleus assay. Eighty ICR male mice were fed AIN-76 diet supplemented with ground freeze-dried EF at 0.0%, 0.8%, 1.6% and 3.2% for 2 weeks prior to the administration of both direct-acting, mitomycin C (MMC), and indirect-acting, 7, 12-dimethylbenz(a) anthracene (DMBA) clastogens. Peripheral blood samples were collected from mice just before administration of clastogen and at 24 and 48 h thereafter for MMC. Blood samples were collected at the same times and after 72 h for DMBA. Then, reticulocytes in blood samples were counted using fluorescent microscopy. The results indicated that EF had no clastogenic effect in mice. All doses of diets supplemented with EF decreased the number of micronucleated peripheral reticulocytes in all the MMC-treated groups in a dose dependent manner, but significant reduction was found only at 1.6% and 3.2% EF in the DMBA-treated groups. It can be concluded that EF has no clastogenicity, but possesses anticlastogenic potential against both direct- and indirect-acting types of clastogen in mice.

• Molecules and Cells
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• v.21 no.3
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• pp.401-410
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• 2006

The plastid transformation approach offers a number of unique advantages, including high-level transgene expression, multi-gene engineering, transgene containment, and a lack of gene silencing and position effects. The extension of plastid transformation technology to monocotyledonous cereal crops, including rice, bears great promise for the improvement of agronomic traits, and the efficient production of pharmaceutical or nutritional enhancement. Here, we report a promising step towards stable plastid transformation in rice. We produced fertile transplastomic rice plants and demonstrated transmission of the plastidexpressed green fluorescent protein (GFP) and aminoglycoside 3′-adenylyltransferase genes to the progeny of these plants. Transgenic chloroplasts were determined to have stably expressed the GFP, which was confirmed by both confocal microscopy and Western blot analyses. Although the produced rice plastid transformants were found to be heteroplastomic, and the transformation efficiency requires further improvement, this study has established a variety of parameters for the use of plastid transformation technology in cereal crops.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.9 s.252
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• pp.834-841
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• 2006

In the present wort the Laser-induced Fluorescence (LIF) technique and Confocal Laser Scanning Microscopy (CLSM) have been combined to measure the temperature distribution across a micro-scale liquid layer as a direct and non-invasive method. Only the fluorescent light emitted from a very thin volume around a focal plane can be selectively detected, and it enables us to measure the liquid temperatures even at the close vicinity of the walls. As an experimental verification, a test section consists of two flat plates (for heating and cooling, respectively) separated by about 240 microns was made, and the methanol mixed with a temperature-sensitive dye, Rhodamine B, was filled in the gap between them. The measured temperature distribution across the gap showed good linearity, which is a typical characteristic of conduction heat transfer through a thin liquid layer. In result, the CLSM-LIF technique proposed in the present study was found to be a promising method to measure the local temperatures in the liquid flow field in microfluidic devices.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.59-66
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• 2013

Colonization studies previously performed with a green-fluorescent-protein, GFP, labeled derivative of Bacillus amyloliquefaciens FZB42 revealed that the bacterium behaved different in colonizing surfaces of plant roots of different species (Fan et al., 2012). In order to extend these studies and to elucidate which genes are crucial for root colonization, we applied targeted mutant strains to Arabidopsis seedlings. The fates of root colonization in mutant strains impaired in synthesis of alternative sigma factors, non-ribosomal synthesis of lipopeptides and polyketides, biofilm formation, swarming motility, and plant growth promoting activity were analyzed by confocal laser scanning microscopy. Whilst the wild-type strain heavily colonized surfaces of root tips and lateral roots, the mutant strains were impaired in their ability to colonize root tips and most of them were unable to colonize lateral roots. Ability to colonize plant roots is not only dependent on the ability to form biofilms or swarming motility. Six mutants, deficient in abrB-, sigH-, sigD-, nrfA-, yusV and RBAM017410, but not affected in biofilm formation, displayed significantly reduced root colonization. The nrfA- and yusV-mutant strains colonized border cells and, partly, root surfaces but did not colonize root tips or lateral roots.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.4
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• pp.965-972
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• 2005

To investigate the effects of Trichosanthes semen extract on the growth and apoptosis of human uterine cervical carcinoma cells. Effects of Trichosanthes semen extract on the growth of ME-180 cells were assayed by MTT assay. Apoptosis induced by Trichosanthes semen extract was detected by fluorescent microscopy, DNA fragmentation analysis and flow cytometry. Caspase-3 and caspase-8 activities were assayed. Trichosanthes semen extract induced ME-180 cells to die in a dose- and time-dependent manner. ME-180 cells treated with Trichosanthes semen extract exhibited typical characteristics of apoptosis. The population of Sub-G1 cells increased significantly, and the cells represented the reduced size, condensed chromatin and apoptotic bodies. They showed the decreased mitochondrial membrane potential and increased activities of caspase-3 and caspase-8. The results suggest that Trichosanthes semen extract induced ME-180 cell apoptosis and the activation of caspase and mitochondrial pathway were involved in the process of Trichosanthes semen extract-induced apoptosis.

• Korean Journal of Veterinary Service
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• v.22 no.1
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• pp.43-52
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• 1999

Presently, viral isolation in the diarrheal feces can be reached by many tools such as fluorescent antibody test(FA), negative contrast electron microscopy(NCEM), virus neutralization test, cell culture, and so on. The purpose of the study was to aimed at the establishment of simplified NCEM technique which can be efficiently applied for diarrheal feces and also the understanding on prevalence of viral-induced diarrhea in calves. One hundred fourty-seven korean indigenous calves with diarrhea were examined to their feces by the modified NCEM. Among them, 98(66.7%) were confirmed to have one or more viruses in feces. The viruses detected were identified as rotavirus(33.3%), coronavirus(16.3% ), togavirus(10.2%) and herpesvirus(0.7%). Ten cases of combined viral infection were consisted of 8 with rotavirus+coronavirus, one with rotavirus+togavlrus and one with rotavirus+herpesvirus. Dirrheal types could classified by yello-wish watery(44.9a ), blood-tinged(19.7% ), white watery(17.7% ) , brownish watery(14.3%), greenish watery(3.4%) diarrhea, respectively. Yellowish watery diarrhea(66cases) was frequently included rotavirus(31.8%), coronavirus(15.2%), and togavirus(13.6%), respectively. Consequently, these results suggest that the modified NCEM is reliable and efficient diagnostic tool for detection of viruses in the diarrheal feces and many calves rearing in Chonnam province have been exposed to some enteric viral agents mainly including rotavirus and coronavirus.

• Journal of Microbiology
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• v.45 no.1
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• pp.11-14
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• 2007

Over the last few years, the endophytic bacterial community associated with citrus has been studied as an important component interacting with Xylella fastidiosa, the causal agent of citrus variegated chlorosis(CVC). This bacterium may also colonize some model plants, such as Catharanthus roseus and Nicotiana clevelandii. In the present study, we compared the endophytic colonization of Citrus sinensis and Catharanthus rose us using the endophytic bacteria Klebsiella pneumoniae. We chose an appropriate strain, K. pneumoniae 342 (Kp342), labeled with the GFP gene. This strain was inoculated onto seedlings of C. sinensis and C. roseus. The isolation frequency was determined one week after the inoculation and the endophytic colonization of K. pneumoniae was observed using fluorescence microscopy. Although the endophytic bacterium was more frequently isolated from C. roseus than from C. sinensis, the colonization profiles for both host plants were similar, suggesting that C. roseus could be used as a model plant to study the interaction between endophytic bacteria and X. fastidiosa.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.425-430
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• 2014

Amyloidogenic proteins often exhibit fibrillar polymorphism through alternative assembly processes, which has been considered to have possible pathological implications. Here, firefly luciferase (LUC) is shown to induce amyloid polymorphism of ${\alpha}$-synuclein, the major constituent of Lewy bodies found in Parkinson's disease, by acting as a novel template. The drastically accelerated fibrillation kinetics of ${\alpha}$-synuclein with LUC required the nucleation center produced by the active enzyme of LUC. Fluorescent dye binding, transmission electron microscopy, and Fourier transformed infrared spectroscopy revealed the morphologically distinctive amyloid fibrils of ${\alpha}$-synuclein prepared in the absence or presence of LUC. As the altered morphological characteristics became inherent to the mature fibrils, those properties were inherited to next-generations via nucleation-dependent fibrillation process. The seed control, therefore, would be an effective means to modify amyloid fibrils with different biochemical characteristics. In addition, the LUC-directed amyloid fibrillar polymorphism also suggests that other cellular biomolecules including enzymes in general are able to diversify amyloid fibrils, which could be self-propagated with diversified biological activities, if any, inside cells.

• KSBB Journal
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• v.26 no.5
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• pp.422-426
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• 2011

Alginate bead has been supplemented with various polymers to control permeability and to enhance mechanical strength. In this report, fibroin-reinforced alginate hydrogel was prepared, in which spatial localization of fibroin molecules was investigated. Confocal laser scanning microscopy revealed that fibroin molecules formed a fibrous network in the alginate-fibroin beads, which was expected to enhance mechanical strength as same as in many composite materials. Uniaxial compression test showed that fibroin-reinforced alginate beads had increased mechanical strength only after methanol treatment that caused ${\beta}$-sheet formation among fibroin molecules. Simultaneous curing and dialysis of alginate beads were carried out to remove excesscalcium but to retain fibroin in the dialysis chamber, which fabricated beads without internal fibrous fluorescent stains. Fibroin molecules were only found beneath the surface of the beads. The fibroin-diffused shell was further processed to form a thick wall after drying or was mobilizedto the centre of the bead by methanol treatment. Accordingly, the structure analyses provide processing methods of fibroin to form a wall or center clumps, which could be applied to design controlled delivery device.

• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.623-627
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• 2000

Aggregation of hydrophobically end-capped poly(ethylene oxide)s: HEURs, denoted as $C_8$$EO_{380}$$C_8$, $C_12$$CO_{600}$$C_{12}$, and $C_{18}$$EO_{860}$$C_{18}$,are described using static fluorescence, dynamic light scattering, and atomic force microscope (AFM) techniques. The CAC (critical aggregation concentration) was determined by com-paring two fluorescent peaks which were influenced by the polarity of the probe dye molecules, pyrene. The aggregation occurs in concentrations higher than 10 g/L of $C_8$$EO_{380}$$C_8$ and the CAC decreases by increasing the side chain length. The dynamic light scattering experiment shows fast mode and slow mode decays, and both are diffusive. The fast mode does not depend on the concentration, but the slow mode shows concentration dependence influenced by the formation of an aggregated structure. The hydrophobic end groups effect more dominantly than the main chains for the formation of HEUR micelles. By increasing the concentration, the HEUR micelles change their structure from spheres to rodlike micelles, and finally make fused structures, which were visualized with atomic force microscopy.