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41.
Dae Sub Song Youn Jeong Lee Ok Mi Jeong Yong Joo Kim Chan Hee Park Jung Eun Yoo Woo Jin Jeon Jun Hun Kwon Gun Woo Ha Bo Kyu Kang Chul Seung Lee Hye Kwon Kim Byeong Yeal Jung Jae Hong Kim Jin Sik Oh 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(4):323-329
Active serologic surveillance is necessary to control the spread of the avian influenza virus (AIV). In this study, we evaluated a commercially-available cELISA in terms of its ability to detect AIV antibodies in the sera of 3,358 animals from twelve species. cELISA detected antibodies against reference H1- through H15-subtype AIV strains without cross reactivity. Furthermore, the cELISA was able to detect antibodies produced following a challenge of the AIV H9N2 subtype in chickens, or following vaccination of the AIV H9 or H5 subtypes in chickens, ducks and geese. Next, we tested the sensitivity and specificity of the cELISA with sera from twelve different animal species, and compared these results with those obtained by the hemagglutination-inhibition (HI) test, the "gold standard" in AIV sera surveillance, a second commercially-available cELISA (IZS ELISA), or the agar gel precipitation (AGP) test. Compared with the HI test, the sensitivities and specificities of cELISA were 95% and 96% in chicken, 86% and 88% in duck, 97% and 100% in turkey, 100% and 87% in goose, and 91% and 97% in swine, respectively. The sensitivities and specificities of the cELISA in this study were higher than those of IZS ELISA for the duck, turkey, goose, and grey partridge sera samples. The results of AGP test against duck and turkey sera also showed significant correlation with the results of cELISA (R-value >0.9). In terms of flock sensitivity, the cELISA correlated better with the HI test than with commercially-available indirect ELISAs, with 100% flock sensitivity. 相似文献
42.
In Seong Choi Seung Gon Wi Se Ra Jung Darshan H. Patel Hyeun-Jong Bae 《Journal of Wood Science》2009,55(5):329-334
β-Glucosidase (β-1,4-D-glucoside glucohydrolase: EC.3.2.1.21) catalyzes the hydrolysis of β-glucosidic bonds between saccharides
and aryl or alkyl groups. A gene encoding β-glucosidase from Bacillus licheniformis KCTC 1918, an anaerobic spore-forming soil bacterium, was cloned and characterized. The structural gene for the β-glucosidase
consists of 1410 bp encoding 469 amino acid residues, and has a molecular weight of 53.4 kDa as estimated by sodium dodecyl
sulfate polyacrylamide gel electrophoresis with 12% separating gel. The enzyme activity was determined against pNPG as a substrate. The enzyme was optimally active at pH 6.0 (citrate-phosphate buffer) and 47°C. β-Glucosidase retained
100% of its original activity for 24 h. The activity of the enzyme was stimulated by glycerol and urea and was decreased by
Ca2+, Cu2+, Hg2+, Mg2+, and Mn2+. In particular, Cu2+ had the strongest negative effect on β-glucosidase activity. The purified β-glucosidase was active against pNPG and cellobiose. When the β-glucosidase was tested for cellulose hydrolysis, the supplement of β-glucosidase with cellulose
increased the glucose yield from pine wood powder by 139.8%. 相似文献
43.
44.
Hyeok Ran Kwon Gyung Ja Choi Yong Ho Choi Kyoung Soo Jang Nack‐Do Sung Mun Seong Kang Yilseong Moon Seung Kyu Lee Jin‐Cheol Kim 《Pest management science》2010,66(6):634-639
BACKGROUND: Pine wilt disease (PWD) is very complex and has been reported to be caused by pine wood nematode, Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle, and its accompanying bacteria. However, there is no report on the control of PWD by antibacterial agent. The present study was performed to investigate disease control efficacy of antibacterial agents against PWD. RESULTS: Among six antibacterial antibiotics tested, oxolinic acid (OA) showed the strongest antibacterial activity against five bacteria isolated from three strains of pine wood nematode. In in vivo assay, it effectively suppressed the development of PWD in three‐year‐old seedlings of Pinus densiflora Sieb. & Zucc.; it showed 71% control when injected at 3 mg per seedling. A mixture of OA and the nematicidal agent abamectin (Ab) showed higher disease control efficacy against PWD than either OA or Ab alone. In addition, OA alone and a mixture of OA and Ab also controlled PWD in approximately 20‐year‐old pine trees under field conditions. CONCLUSION: This is the first report on the suppression of PWD by OA. The result strongly indicates that PWD could be controlled by antibacterial antibiotic alone and a combination of antibacterial and nematicidal agents. Copyright © 2010 Society of Chemical Industry 相似文献
45.
Woong Yoon Jung Min Ryu Min Young Lee Yong Ju Moon Sang Hun Lee Jae Hong Park Seung Pil Yun Min Woo Jang Sung Su Park Ho Jae Han 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(3):185-189
Micropigs are the most likely source animals for xenotransplantation. However, an appropriate method for evaluating the lung of micropigs had not been established. Therefore, this study was performed to evaluate the feasibility of 64-channel multi-detector row computed tomography (MDCT) to measure the diameter of the pulmonary arteries and the lung volume in micropigs. The mean diameters of the trachea, and left and right bronchi were 1.6 ± 0.17, 1.18 ± 0.14, and 1.1 ± 0.11 cm, respectively. The mean diameters of the main, right, and left pulmonary arteries were 1.38 ± 0.09, 1.07 ± 0.26, and 0.98 ± 0.13 cm and the diameters of right, left, and common inferior pulmonary veins were 0.97 ± 0.20, 0.76 ± 0.20, and 1.99 ± 0.26 cm, respectively. The mean lung volume was 820.3 ± 77.11 mL. The data presented in this study suggest that the MDCT may be a noninvasive, rapid, and accurate investigational method for pulmonary anatomy in living lung donors. 相似文献
46.
Youn?Hee?Jeon Won?Young?Jeong Jung?Woo?Park Seung?Kook?AnEmail author 《Fibers and Polymers》2003,4(4):151-155
The abrasion behavior of three kinds of warp knitted fabrics, which are normally used for upper sole of footwear, was evaluated.
We measured the changes of mechanical and structural properties of each sample as abrasion cycle increased. Each sample showed
similar trends in compression and surface properties but there were significant differences in abrasion rate among the samples.
The mechanical properties showed remarkable differences with directions. The frictional coefficient (MIU) of fabric surface
increased at the beginning of abrasion and decreased as abrasion cycles increased. The weight and thickness of the fabric
linearly decreased with abrasion cycles. The surface roughness (SMD) and the compressional resilience (RC) decreased as abrasion
cycles increased while compressional energy (WC) increased. 相似文献
47.
The self-assembly of asymmetric ABC triblock copolymers in the ordered structure is investigated using an isothermal-isobaric
molecular dynamics simulation. Unlike symmetric ABC triblock copolymers, more fascinating morphologies are observed in asymmetric
ones because of a larger difference of incompatibility between the components. Various modes of self-assembly in assymmetric
ABC triblock copolymers are also observed depending on the block composition. When the composition of block A is changed from
0.125 to 0.25 at the samef
B
=0.25, the morphological transition from the “cylinder in cylinder” to “cylinders at cylinder” structure is observed in the
simulation. In the case of ABC triblocks withf
B
=0.5, a lamellar-type structure is changed to a cylinder-type structure with increasing the length of block A. When the mid-block
length increases further tof
B
=0.625, the “spheres on cylinder” structure is observed in both the A10B50C20 and A20B50C10 triblocks. From these results, the phase diagram of ABC triblock copolymers can be constructed.
Dedicated to Professor Won-Jei Cho on the occasion of his retirement. 相似文献
48.
Kim SK Kim YC Lee S Kim JC Yun MY Kim IS 《Journal of agricultural and food chemistry》2011,59(3):934-938
Microorganisms capable of growth on oils are potential sources of biopesticides, as they produce complex molecules such as biosurfactants and lipopeptides. These molecules have antimicrobial activity against plant pathogens, but few data are available on their insecticidal activity. The present study describes the insecticidal activity of a rhamnolipid isolated from diesel oil-degrading Pseudomonas sp. EP-3 (EP-3). The treatment of cell-free supernatants of EP-3 grown on glucose-mineral medium for 96 h led to > 80% mortality of aphids (Myzus persicae) within 24 h. Bioassay-guided chromatography coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MADLDI-TOF MS) and (1H, 13C) nuclear magnetic resonance (NMR) analyses was employed to isolate and identify the EP-3 insecticidal metabolites. Dirhamnolipid, with molecular formulas of C??H??O?? and C??H??O??, was identified as a main metabolite exhibiting insecticidal activity against aphids. Dirhamnolipid showed a dose-dependent mortality against aphids, producing about 50% mortality at 40 μg/mL and 100% mortality at 100 μg/mL. Microscopy analyses of aphids treated with dirhamnolipid revealed that dirhamnolipid caused insect death by affecting cuticle membranes. This is the first report of rhamnolipid as an insecticidal metabolite against M. persicae. Rhamnolipid shows potential for use as a pesticide to control agricultural pests. 相似文献
49.