• The Korean Journal of Physiology
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• v.22 no.2
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• pp.245-257
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• 1988

The present study was undertaken to investigate the effect of clonidine on the response of the dorsal horn cells to intra-arterially administered bradykinin $(BK:40{\mu}g)$ and $K^+(4mg)$ in spinal cats and cats with intact spinal cord. The change in the activities of low threshold (LT), high threshold (HT) and wide dynamic range (WDR) cells induced by BK and $K^+$ were determined before and after treatment of animals with clonidine. Also studied was mechanism of inhibitory action of clonidine on the responses of dorsal horn cells to the chemical algogenics. Number of WDR cell responded to intra-arterially administered BK and $K^+$ was greater in spinal animals than in cats with intact spinal cord. Following administration of BK or $K^+$ no change was observed in the activity of LT cell whereas activity of HT cell increased invariably. The increased response of HT cell to BK and $K^+$ was markedly suppressed by clonidine. On the other hand, such inhibitory actions of clonidine were almost completely blocked by yohimbine. The majority of WDR cells were activated by $K^+$ while response of WDR cells to BK was diverse (excitatory, inhibitory or mixed). These results indicate that clonidine inhibits responses of the dorsal horn cells not only to thermal or mechanical stimulations but also to chemical algogenics, and that the inhibitory action of clonidine is generally mediated through excitation of ${\alpha}_2-adrenoreceptors$.

• Animal Bioscience
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• v.36 no.2
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• pp.315-321
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• 2023

Objective: The study was conducted to investigate the dephosphorylation of Pseudomonas aeruginosa flagellin (PA FLA) by sweet potato purple acid phosphatase (PAP) and the effect of the enzyme on the flagellin-mediated inflammatory response in the A549 lung epithelial cell line. Methods: The activity of sweet potato PAP on PA FLA was assayed at different pH (4, 5.5, 7, and 7.5) and temperature (25℃, 37℃, and 55℃) conditions. The release of interleukin-8 (IL-8) and the activation of nuclear factor kappa- light-chain-enhancer of activated B cells (NF-κB) in A549 cells exposed to PA FLA treated with or without sweet potato PAP was measured using IL-8 and NF-κB ELISA kits, respectively. The activation of toll-like receptor 5 (TLR5) in TLR5-overexpressing HEK-293 cells exposed to PA FLA treated with or without sweet potato PAP was determined by the secreted alkaline phosphatase-based assay. Results: The dephosphorylation of PA FLA by sweet potato PAP was favorable at pH 4 and 5.5 and highest at 55℃. PA-FLA treated with the enzyme decreased IL-8 release from A549 cells to about 3.5-fold compared to intact PA FLA at 1,000 ng/mL of substrate. Moreover, PA-FLA dephosphorylated by the enzyme repressed the activation of NF-κB in the cells compared to intact PA FLA. The activation of TLR5 by PA-FLA was highest in TLR-overexpressing HEK293 cells at a substrate concentration of 5,000 ng/mL, whereas PA FLA treated with the enzyme strongly repressed the activation of TLR5. Conclusion: Sweet potato PAP has the potential to be a new alternative agent against the increased antibiotic resistance of P. aeruginosa and may be a new conceptual feed additive to control unwanted inflammatory responses caused by bacterial infections in animal husbandry.

• The Korean Journal of Cytopathology
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• v.14 no.1
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• pp.17-21
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• 2003

Insular carcinoma of the thyroid(ICT) is an uncommon thyroglobulin-producing neoplasm, intermediate between well differentiated and anaplastic carcinoma. Only a few publications have addressed the fine needle aspiration cytologic(FNAC) findings from ICT. We experienced a case histologically diagnosed as ICT and with preoperative FNAC in a 52 - year - old woman. The FNAC displayed scanty colloid and abundant monomorphic follicular cells presented singly, in small loose aggregates, and in cohesive trabecular or acinar clusters. Intact insulae of tumor cells were also identified. Necrosis and mitosis were rare. Tumor cells showed round and monomorphic nuclei, finely granular chromatin, and inconspicuous nucleoli. When insular structure is identified in thyroid FNAC specimen, ICT should be included in the differential diagnosis. Herein we discuss and review the cytologic criteria for separation of ICT from other thyroid neoplasms.

• Journal of Microbiology and Biotechnology
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• v.19 no.8
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• pp.836-844
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• 2009

A denitrification bacterium was isolated from riverbed soil and identified as Ochrobactrum sp., whose specific enzymes for denitrification metabolism were biochemically assayed or confirmed with specific coding genes. The denitrification activity of strain G3-1 was proportional to glucose/nitrate balance, which was consistent with the theoretical balance (0.5). The modified graphite felt cathode with neutral red, which functions as a solid electron mediator, enhanced the electron transfer from electrode to bacterial cell. The porous carbon anode was coated with a ceramic membrane and cellulose acetate film in order to permit the penetration of water molecules from the catholyte to the outside through anode, which functions as an air anode. A non-compartmented electrochemical bioreactor (NCEB) comprised of a solid electron mediator and an air anode was employed for cultivation of G3-1 cells. The intact G3-1 cells were immobilized in the solid electron mediator, by which denitrification activity was greatly increased at the lower glucose/nitrate balance than the theoretical balance (0.5). Metabolic stability of the intact G3-1 cells immobilized in the solid electron mediator was extended to 20 days, even at a glucose/nitrate balance of 0.1.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2034-2042
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• 2015

A one-pot process of enzymatic synthesis of deoxythymidine-5'-triphosphate (5'-dTTP) employing whole cells of recombinant Escherichia coli coexpressing thymidylate kinase (TMKase) and acetate kinase (ACKase) was developed. Genes tmk and ack from E. coli were cloned and inserted into pET28a(+), and then transduced into E. coli BL21 (DE3) to form recombinant strain pTA in which TMKase and ACKase were simultaneously overexpressed. It was found that the relative residual specific activities of TMKase and ACKase, in pTA pretreated with 20 mM ethylene diamine tetraacetic acid (EDTA) at 25℃ for 30 min, were 94% and 96%, respectively. The yield of 5'-dTTP reached above 94% from 5 mM deoxythymidine 5'-monophosphate (5'-dTMP) and 15 mM acetyl phosphate catalyzed with intact cells of pTA pretreated with EDTA. The process was so effective that only 0.125 mM adenosine-5'-triphosphate was sufficient to deliver the phosphate group from acetyl phosphate to dTMP and dTDP.

• KSBB Journal
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• v.9 no.2
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• pp.122-126
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• 1994

A new method for the production of isomalto-oligosaccharides from maltose was investigated using intact cells of Aureobasidium pullulaans which had been known to produce fructo-oligosaccharides. The cells showed transglucosylation activity producing isomalto-oligosaccharides at high concentrations of maltose, while they showed a hydrolytic activity at low concentrations of substrate when cultivated at $25^{\circ}C$. The optimum reaction conditions for the isomalto-oligosaccharide production were as follows: substrate concentration, 500g/l maltose; pH, 4.5; temperature, $65^{\circ}C$; cell dosage, 10 unit per gram substrate. Under optimized conditions, the maximum yield of isomalto-oligosaccharides achieved was around 48% (w/w). At the early period of reaction, panose was selectively produced from maltose, and thereafter isomaltotriose was synthesized by utilizing panose as a substrate when maltose consumption was discontinued.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.2
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• pp.245-251
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• 2006

The aim of this study was to investigate the effects of caponization on the bone characteristics, biomechanical property and histology in Taiwan country chickens fed to market age of 26 wks. Male Taiwan country chickens $D{\times}L_2$ were caponized or sham-operated at 8 wks of age, and selected healthy sham-operated and completely caponized chickens (prominent degenerated comb) were selected at 16 wks old and fed to 26 wks old for the trials. Fifteen intact male chickens (Intact), sham-operated chickens (Sham) and caponized chickens (Capon) were assigned for trial 1, and sixteen Intact and Capon were assigned for trial 2. Results in trial 1 showed that the abdominal fat and relative abdominal fat weights of Capon were significantly heavier than Intact and Sham (p<0.05), while the tibia weight and relative weight were the lightest (p<0.05). The tibia breaking strength, bending moment and stress of Capon were the poorest among groups (p<0.05). The trial 2 produced the similar observation that Capon were significantly lighter than Intact (p<0.05) in the tibia weight, relative tibia weight and their biomechanical properties. On histological determinations, Capon showed a thinner cartilage end and fewer chondrocytes (about 50%) and trabecular, and bigger marrow cavity; while decreased hemopoietic cells number with increased adipocytes than Intact observed by H&E stain and at low magnification. At high magnification, Capon showed a decrease in the chondrocyte size by 33 to 50%, with smaller nucleus located near the cell membrane, and exhibited monocellular form chondrocytes. Capon also showed a less strongly acidic sulfated mucosubstance with weaker dyeing property within cartilage zone, and smaller chondrocytes size by Alcian blue stain.

• Molecules and Cells
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• v.26 no.2
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• pp.113-120
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• 2008

Laser light microscopy enables observation of various simultaneously occurring events in living cells. This capability is important for monitoring the spatiotemporal patterns of the molecular interactions underlying such events. Two-photon excited fluorescence microscopy (two-photon microscopy), a technology based on multiphoton excitation, is one of the most promising candidates for such imaging. The advantages of two-photon microscopy have spurred wider adoption of the method, especially in neurological studies. Multicolor excitation capability, one advantage of two-photon microscopy, has enabled the quantification of spatiotemporal patterns of $[Ca^{2+}]_i$ and single episodes of fusion pore openings during exocytosis. In pancreatic acinar cells, we have successfully demonstrated the existence of "sequential compound exocytosis" for the first time, a process which has subsequently been identified in a wide variety of secretory cells including exocrine, endocrine and blood cells. Our newly developed method, the two-photon extracellular polar-tracer imaging-based quantification (TEPIQ) method, can be used for determining fusion pores and the diameters of vesicles smaller than the diffraction-limited resolution. Furthermore, two-photon microscopy has the demonstrated capability of obtaining cross-sectional images from deep layers within nearly intact tissue samples over long observation times with excellent spatial resolution. Recently, we have successfully observed a neuron located deeper than 0.9 mm from the brain cortex surface in an anesthetized mouse. This microscopy also enables the monitoring of long-term changes in neural or glial cells in a living mouse. This minireview describes both the current and anticipated capabilities of two-photon microscopy, based on a discussion of previous publications and recently obtained data.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.1021-1027
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• 1997

We examined some properties of yeast cell wall lytic enzyme produced by Dicyma sp. YCH-37. Several metal ions, reducing reagents, and chemical modifiers have little effects on the lytic activity, except guanidine-HCl. Yeast cells of early log phase were more susceptible to the enzyme than those of stationary phase, and heat-treated cells were more easily lysed than intact living ones. Yeast cells pretreated with organic solvents such as butanol and acetone were more susceptible to the enzyme than intact living ones. Yeast cells cultured in Yeast extract-Malt extract medium containing 0.5 M ammonium sulfate were easily lysed by the lytic enzyme, and yeast cells cultured without shaking were more easily lysed by the enzyme than those with shaking. When SDS, ${\beta}-mercaptoethanol$, Triton X-100, sodium sulfite, and KCl were added to enzyme reaction mixture each, lysis of yeast cells was more effective.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.309-314
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• 1994

To develop simple and efficient transformation methods of monocotyledonous plane, electroporation-mediated delivery of DNA into intact embryogenic cell clumps was investigated in zoysiagrass and rice. Calli of zoysiagrass, induced from 3-week-old immature embryos, were suspension-cultured in MS basic medium supplemented with 1.0 mg/t 2.4-D and used for elechuporation. Calli, derived from immature inflorescences of 20 mm lenth of rice, were also suspension-cultured on N6 basic medium supplemented with 1.0 mg/L 2.4-D. Suspension-cultured embryogenic cell clumps were electroporated in liqid MS medium added with a Plasmid DNA (30 $\mu\textrm{m}$/ml), pGA1074, encoding ${\beta}$-glucuronidiase (GUS). DNA delivery into the cells through cell walls and cell membrane was confirmed by the transient expression of the GUS gene. Cell clumps of zoysiagrass and rice, electroporated with 400 volt at 800 pF capacitance, expressed GUS gene activity at a mean frequency of 25 units (one unit = one clony of blue cells) per 200 ${\mu}\ell$ of packed cell volume. Untreated cells and healed non-embryogenic cells did not exhibit GUS activity These results indicate that electroporation-mediated transformation can use intact embryogenic cells (thus avoiding the use protoplasts) in zoysiagrass and rice.