• Korean Journal of Plant Tissue Culture
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• v.25 no.5
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• pp.295-299
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• 1998

To detect the effects of gelling agent brands and concentration on rice anther culture, anthers of rice(O. sativa L. japonica, cv, Nagdongbyeo) were inoculated on N6-Y1 basic media supplemented with 0.4~1.6% Bacto agar(Difco, 04140-01), Agarose(Sigma, Type 1) and 0.2~0.8% Gelrite(Kelco, 143364) as gelling agents. On 0.4% Bacto agar and Agarose media, the frequency of callus formation which was significantly decreased in proportion to gelling agent's concentration was 39% and 55%, respectively. On 0.6% Gelrite media, the frequency of callus formation which was not statistically significant among the 0.2~0.8% concentration was 44%. Calli derived from the higher concentration of gelling agents showed embryogenic with slow growth, small, whitish and hard shape compare to that of the lower concentration. The frequency of green plant regeneration was high not only in calli derived from the higher concentration but also in plant regeneration medium with the higher concentration after callus transfer. Calli derived from the higher concentration was effective to maintain the frequency of green plant regeneration up to 60 days after anther inoculation. Introduction of 0.6~0.8% Geltite for callus formation, then transferred 1.6% Bacto agar and Agarose or 0.8% Gelrite for green plant regeneration was effective to increase anther culture efficiency.

• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.314-321
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• 2015

Agar-hydrolyzing bacteria were isolated from the coastal sea water of Jeju Island. One isolate, designated as S4, was selected for further study. The S4 cells were Gram-negative and rod-shaped with smooth beige surfaces and single polar flagellum. Cells were grown at $15-42^{\circ}C$, 0.5-5% (w/v) NaCl, between pH 6.0 and 9.0, and in media containing 0.5-5% (w/v) NaCl. The G+C content was 49.93 mol%. The major fatty acids (>15%) were $C_{18:1}{\omega}7c$, $C_{16:0}$ and Summed feature 3 (comprising $C_{16:1}{\omega}7c/iso-C_{15:0}$ 2-OH). Based on 16S rRNA sequencing and biochemical and chemotaxonomic characteristics, the strain was designated as Vibrio sp. S4. In liquid culture supplemented with 0.1% agar the cell density and agarase activity reached a maximum level in 72 h, while agarase activity in the culture without agar was negligible, implying agarose expression is induced by agar. The optimum pH and temperature for the extracellular crude agarase of S4 were 7.0 and $45^{\circ}C$, respectively. However, it also exhibited 98.6% and 87.6% at $40^{\circ}C$ and $50^{\circ}C$, respectively, of the maximum activity seen at $45^{\circ}C$. The crude agarase hydrolyzed agarose into (neo)agarotetraose and (neo)agarohexaose.

• Journal of the Korean Society of Radiology
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• v.84 no.5
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• pp.1110-1122
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• 2023

Purpose This study aimed to assess the variability of transrectal shear wave elastography (SWE) using a designed phantom. Materials and Methods In a phantom, the SWE values were examined by two radiologists using agarose and emulsion silicone of different sizes (1, 2, and 3 cm) and shapes (round, cubic) at three depths (1, 2, and 3 cm), two region of interest (ROI) and locations (central, peripheral) using two ultrasound machines (A, B from different vendors). Variability was evaluated using the coefficient of variation (CV). Results The CVs decreased with increasing phantom size. Significant changes in SWE values included; agarose phantom at 3 cm depth (p < 0.001; machine A), 1 cm depth (p = 0.01; machine B), emulsion silicone at 2 cm depth (p = 0.047, p = 0.020; both machines). The CVs increased with increasing depth. Significant changes in SWE values included; 1 cm agarose (p = 0.037, p = 0.021; both machines) and 2 cm agarose phantom (p = 0.047; machine A). Significant differences in SWE values were observed between the shapes for emulsion silicone phantom (p = 0.032; machines A) and between ROI locations on machine B (p ≤ 0.001). The SWE values differed significantly between the two machines (p < 0.05). The intra-/inter-operator agreements were excellent (intraclass correlation coefficient > 0.9). Conclusion The phantom size, depth, and different machines affected the variability of transrectal SWE.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.1001-1002
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• 2009

• Proceedings of the Korean Society of Life Science Conference
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• 2006.09a
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• pp.102.2-102.2
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• 2006

• BMB Reports
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• v.43 no.7
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• pp.468-473
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• 2010

Previously, various inhibitors of cell wall synthesis induced the drp35 gene of Staphylococcus aureus efficiently. To determine whether drp35 could be exploited in antistaphylococcal drug discovery, we cloned the promoter of drp35 ($P_d$) and developed different biological assay systems using an engineered S. aureus strain that harbors a chromosomally-integrated $P_d$ - lacZ transcriptional fusion. An agarose-based assay showed that $P_d$ is induced not only by the cell wall-affecting antibiotics but also by rifampicin and ciprofloxacin. In contrast, a liquid medium-based assay revealed the induction of $P_d$ specifically by the cell wall-affecting antibiotics. Induction of $P_d$ by sublethal concentrations of cell wall-affecting antibiotics was even assessable in a microtiter plate assay format, indicating that this assay system could be potentially used for high-throughput screening of new cell wall-inhibiting compounds.

• Journal of Radiation Protection and Research
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• v.31 no.2
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• pp.65-68
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• 2006

In this study, the extent of plasmid DNA damage was observed according to concentration of BSH(Boron Sulfhydryl Hydride) and irradiation doses of neutron and ${\gamma}$-ray. The plasmid used was both pBR 322 (2870 bp) and ${\Phi}X174$ RF(5386 bp) DNA. Plasmid DNA damage by irradiation in the presence of BSH was analyzed by agarose gel electrophoresis. In the neutron experiment, DNA damage of both plasmid DNAs was increased according to increasing the concentration of BSH and neutron doses. But in the ${\gamma}$-ray experiment, there appeared no dose dependency as compared to the neutron experiment. The extent of the plasmid DNA damage in the presence of BSH was somewhat different according to irradiation by neutron or ${\gamma}$-ray.

• Mycobiology
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• v.39 no.1
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• pp.45-51
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• 2011

This work was conducted to investigate dietary supplementation of oyster mushroom fruiting bodies on biochemical and histological changes in hyper and normocholesterolemic rats. Six-week old female Sprague-Dawley albino rats were divided into three groups of 10 rats each. Feeding a diet containing a 5% powder of Pleurotus ostreatus fruiting bodies to hypercholesterolemic rats reduced plasma total cholesterol, triglyceride, low-density lipoprotein (LDL), total lipid, phospholipids, and LDL/high-density lipoprotein ratio by 30.18, 52.75, 59.62, 34.15, 23.89, and 50%, respectively. Feeding oyster mushrooms also significantly reduced body weight in hypercholesterolemic rats. However, it had no adverse effects on plasma albumin, total bilirubin, direct bilirubin, creatinin, blood urea nitrogen, uric acid, glucose, total protein, calcium, sodium, potassium, chloride, inorganic phosphate, magnesium, or enzyme profiles. Feeding mushroom increased total lipid and cholesterol excretion in feces. The plasma lipoprotein fraction, separated by agarose gel electrophoresis, indicated that P. ostreatus significantly reduced plasma ${\beta}$ and pre-${\beta}$-lipoprotein but increased ${\alpha}$-lipoprotein. A histological study of hepatic cells by conventional hematoxylin-eosin and oil red O staining revealed normal findings for mushroom-fed hypercholesterolemic rats. These results suggest that a 5% P. ostreatus diet supplement provided health benefits by acting on the atherogenic lipid profile in hypercholesterolemic rats.

• BMB Reports
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• v.32 no.6
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• pp.594-598
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• 1999

The Jun and Fos families of eukaryotic transcription factors form heterodimers capable of binding to their cognate DNA enhancer elements. We are interested in searching for inhibitors or antagonists of the binding of the Jun-Fos heterodimer to the activator protein-1 (AP-1) site. The basic-region leucine zipper (bZIP) domain of c-Fos was expressed as a fusion protein with glutathione S-transferase, and allowed to form a heterodimer with the bZIP domain of c-Jun. The heterodimer was bound to glutathione-agarose, to which were added radiolabeled AP-1 nucleotides. After thorough washing, the gel-bound radioactivity was counted. The assay is faster than the coventional electrophoretic mobility shift assay because the gel electrophoresis step and the autoradiography step are eliminated. Moreover, the assay is very sensitive, allowing the detection of picomolar quantities of nucleotides, and is not affected by up to 50% dimethylsulfoxide, a solvent for hydrophobic inhibitors. Curcumin and dihydroguaiaretic acid, recently known inhibitors of Jun-Fos-DNA complex formation, were applied to this Jun-GST-fused Fos system and revealed to decrease the dimer-DNA binding.

• Toxicological Research
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• v.25 no.3
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• pp.113-118
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• 2009

Cell death induced by menadione (vitamin K-3,2-methyl-1,4-naphthoquinone) has been investigated in human promyelocytic leukemia HL-60 cells. Menadione was found to induce both apoptosis and necrosis in HL-60 cells. Low concentration ($1{\sim}$50 ${\mu}$M) of menadione induced apoptotic cell death, which was demonstrated by typical DNA ladder patterns on agarose gel electrophoresis and flow cytometry analysis. In contrast, a high concentration of menadione (100 ${\mu}$M) induced necrotic cell death, which was demonstrated by DNA smear pattern in agarose gel electrophoresis. Necrotic cell death was accompanied with a great reduction of cell viability. Menadione activated caspase-3, as evidenced by both increased protease activity and proteolytic cleavage of 116 kDa poly(ADP-ribose) polymerase (PARP) into 85 kDa cleavage product. Caspase-3 activity was maximum at 50 ${\mu}$M of menadione, and very low at 100 ${\mu}$M of menadione. Taken together, our results showed that menadione induced mixed types of cell death, apoptosis at low concentrations and necrosis at high concentrations in HL-60 cells.