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151.
Min-Hee Kang Min-Joo Chae Jang-Won Yoon Seung-Gon Kim So-Young Lee Jong-Hyun Yoo Hee-Myung Park 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(3):409-415
The prevalence, virulence potential, and antibiotic resistance of ophthalmic Staphylococcus pseudintermedius (SP) isolated from dogs were examined. Sixty-seven Staphylococcus species were isolated from ophthalmic samples and surveyed for species-specific sequences in the Staphylococcus intermedius group (SIG) nuclease gene (SInuc), exfoliative toxin gene for SIG (siet), and antibiotic resistance genes (blaZ and mecA). PCR-restriction fragment length polymorphism analysis of the pta gene was also performed. Fifty isolates were identified as SIG strains, all of which were found to be SP. The blaZ gene was detected in 42 of the 50 SP strains and mecA gene was observed in 18 of the 50 SP strains. The 50 SP strains were most susceptible to amoxicillin/clavulanic acid (94%) and chlorampenicol (70%), and highly resistant to tetracycline (94%) and penicillin (92%). It was also found that 16 (88.9%) mecA-positive SP strains were resistant to oxacillin, tetracycline and penicillin. All mecA-positive SP were resistant to more than four of the eight tested antibiotics and therefore considered SP with multi-drug resistance (MDR). Our results indicate a high prevalence of antibiotic resistance genes in ophthalmic SP along with a close relationship between MDR SP strains and the mecA gene. Based on our findings, judicious administration of antibiotics to companion dogs is necessary. 相似文献
152.
The thermal degradation of poly(ethylene terephthalate-co-isophthalate)s (PETIs) is investigated by using isothermal thermogravimetric analysis at the temperature range of 280–310°C.
The degradation rate of PETIs is increased as the mole ratio of ethylene isophthaloyl (EI) units in PETIs increases. The activation
energies for the thermal degradation of poly(ethylene terephthalate), PETI(5/5), and poly(ethylene isophthalate) are 33.4,
16.6, and 8.9 kcal/mole, respectively. The degradation rate of PETIs is influenced by their volatile cyclic oligomer components
formed during the polymerization and the thermal degradation. It is simulated by the rotational isomeric state model that
the content of cyclic dimer in PETIs, which is the most volatile cyclic oligomer component, increases with the EI units in
PETIs. 相似文献
153.
UV-curable polyurethane acrylate prepolymers were prepared from diisocyanates [isophorone diisocyanate (IPDI), 2,4-toluene
diisocyanate (TDI), or 4,4′-dicyclohexylmethane diisocyanate (H12MDI)], diols [ethylene glycol (EG), 1,4-butane diol (BD), or 1,6-hexane diol (HD)], polypropylene glycol as a polyol. UV-curable
mixtures were formulated from the prepolymer (90 wt%), reactive diluent monomer trimethylol propane triacrylate (10 wt%),
and photoinitiator 1-hydroxycyclohexyl ketone (3 wt% based on prepolymer/diluent). The effects of different diisocyanates/low
molecular weigh diol on the dynamic mechanical thermal properties and elastic recovery of UV-cured polyurethane acrylate films
were examined. The tensile storage modulus increased a little in the order of EG>BD>HD at the same diisocyanate. Two loss
modulus peaks for all samples are observed owing to the glass transition of soft segments (T
gs
) and the glass transition temperature of hard segments (T
gh
). For the same diisocyanate,T
gs
decreased, however,T
gh
increased, in the order of HD>BD>EG. The elastic recovery also increased in the order of HD>BD>EG at the same diisocyanate.
In case of same diols,T
gh
increased in the order of H12MDI>TDI>IPDI significantly. The ultimate elongation and elastic recovery increased in the order of TDI>IPDI>H12MDI at the same diol. 相似文献
154.
This research is to examine the reducing power of bacterial single strain and the mixture of strains. Four strains of Dietzia sp. KDB1 (KC433534), Nesterenkonia sp. KDB2 (KC433535), Nesterenkonia sp. KDB3 (KC433536), and Nesterenkonia sp. KDB4 (KC433537) separated from the fermented indigo vat were cultivated in aerobic condition. Natural indigo of the niram powder obtained from the water extract of Polygonum tinctorium and synthetic indigo purchased was used after sterilization. Natural and synthetic indigo samples were reduced with the strains in an incubator. Oxidation/reduction potential and pH of the mixture of indigo and strain(s) solutions were measured at the same intervals of elapsed time. Dyeing test was applied to evaluate the reduction power of bacterial strains isolated. Ramie fabric was used for the indigo dyeing and its color strength was determined from the reflectance at 660 nm and expressed as K/S values by using a spectroscope. CIELAB coordinates were measured with the same spectroscope and H V/C values were obtained by using the conversion program. All the strains showed reducing power onto natural and synthetic indigo samples. With the elapsed time, dye-uptake was increased up to maximum dye-uptake, and then decreased. The potential was dropped rapidly around ?500 mV and then changed very slightly maintaining lower than ?400 mV. The pH measured was decreased with the elapsed time. All the hue values obtained were of bluish purple (PB) shade. On the reducing power represented as dye-uptake, KDB1 strain was the highest among the strains selected for natural indigo and KDB3 strain for synthetic indigo. KDB2 showed the lowest for both of natural and synthetic indigo. Mixture of strains shortened the start time of reduction and that of maximum dye-uptake than any single strain. 相似文献
155.
Hye-Jin Boo Ji-Young Hong Sang-Cheol Kim Jung-Il Kang Min-Kyoung Kim Eun-Ji Kim Jin-Won Hyun Young-Sang Koh Eun-Sook Yoo Jung-Mi Kwon Hee-Kyoung Kang 《Marine drugs》2013,11(8):2982-2999
Fucoidan, a sulfated polysaccharide, has a variety of biological activities, such as anti-cancer, anti-angiogenic and anti-inflammatory. However, the mechanisms of action of fucoidan as an anti-cancer agent have not been fully elucidated. The present study examined the anti-cancer effect of fucoidan obtained from Undaria pinnatifida in PC-3 cells, human prostate cancer cells. Fucoidan induced the apoptosis of PC-3 cells by activating both intrinsic and extrinsic pathways. The induction of apoptosis was accompanied by the activation of extracellular signal-regulated kinase mitogen-activated protein kinase (ERK1/2 MAPK) and the inactivation of p38 MAPK and phosphatidylinositol 3-kinase (PI3K)/Akt. In addition, fucoidan also induced the up-regulation of p21Cip1/Waf and down-regulation of E2F-1 cell-cycle-related proteins. Furthermore, in the Wnt/β-catenin pathway, fucoidan activated GSK-3β that resulted in the decrease of β-catenin level, followed by the decrease of c-myc and cyclin D1 expressions, target genes of β-catenin in PC-3 cells. These results suggested that fucoidan treatment could induce intrinsic and extrinsic apoptosis pathways via the activation of ERK1/2 MAPK, the inactivation of p38 MAPK and PI3K/Akt signaling pathway, and the down-regulation of Wnt/β-catenin signaling pathway in PC-3 prostate cancer cells. These data support that fucoidan might have potential for the treatment of prostate cancer. 相似文献
156.
Won Jung Lee Min Kyoung Shin Seung Bin Cha Han Sang Yoo 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(4):467-472
Swine hepatitis E virus (HEV) is widespread throughout pigs in both developing and industrialized countries. This virus is an important zoonotic agent and a public concern worldwide. Infected pigs are asymptomatic, so diagnosing swine HEV relies on detection of the virus or antibodies against the virus. However, several obstacles need to be overcome for effective and practical serological diagnosis. In this study, we developed an enzyme-linked immunosorbent assay (ELISA) that used a purified recombinant capsid protein of swine HEV. The potential clinical use of this assay was evaluated by comparing it with a commercial kit (Genelabs Technologies, Diagnostics, Singapore). Results of the ELISA were highly correlated with those of the commercial kit with a sensitivity of 97% and specificity of 95%. ROC (receiving operator characteristic) analysis of the ELISA data produced a value of 0.987 (95% CI, 0.977~0.998, p < 0.01). The cut-off value for the ELISA was also determined using negative pig sera. In summary, the HEV-specific ELISA developed in the present study appears to be both practical and economical. 相似文献
157.
Hydro-extraction, enrichment by evaporation, and freeze drying processes were sequentially carried out to extract the colorants from the Rubus coreanus Miquel sludge which was supplied as the waste of the traditional wine process. The dyeing on to human hair was performed at some pH values by using the commercial condition; 0.4 g of human hair, 100 % (on the weight of hair) of the powder of colorants, liquor ratio 1:5, 40 °C and 30 min. The extract was evaluated by UV-vis spectroscopy, antioxidant property (DPPH radical scavenging activity) and antimicrobial activity measurements. Color of the extract in aqueous solution was red at pH 2, violet at intermediate pH condition, and brown at pH 9. Color properties and colorfastness to light and washing were also analyzed for the hair samples dyed with the extract. With the variation of pH, the color of dyed hair was observed mostly BG-RP at pH 2-5 and then changed to YR-GY at pH>6. For the dyed hair samples, light colorfastness was relatively good; the rating 3 was maintained up to 40 hrs. The rating of wash colorfastness was remained 3 for 25 cycles. Results of color analysis and fastness tests confirmed that the colorants from the Rubus coreanus Miquel were successfully applied to hair-dyeing. 相似文献
158.
Da Kyoung Yong Han Yong Jeon Jae Jung Yoo Jung Nam Im Seung Goo Lee 《Fibers and Polymers》2013,14(12):2122-2127
The PAR fiber reinforced PBT composite was manufactured using the PAR/PBT island-in-a-sea fiber. The isothermal crystallization kinetics of the PAR/PBT composite and the neat PBT resin were investigated in the temperature range of 187–199 °C. To calculate the Avrami parameters for analyzing the crystallization behavior, crystallization peaks were measured and analyzed in terms of the crystallization temperature and the inclusion of the PAR fiber. The crystallization rate of the PBT is faster than that of the PAR/PBT composite from the analysis of their relative crystallinity. Consequently, it is considered that the PAR fiber interrupted the crystal nucleation and growth of the PBT matrix. It can be confirmed with the crystallization half time and the crystalline morphologies at the chosen isothermal temperatures. 相似文献
159.
Sung Hee Kim So Yun Jeon Pil J. Yoo Lyong Sun Pu Jun Young Lee 《Fibers and Polymers》2013,14(12):1975-1980
In order to realize flexible organic light emitting diode (OLED), it is critically important to protect moisture and oxygen penetration into the flexible device through the polymer substrates because of intrinsically poor stability of organic materials of OLED to moisture. Since complete protection of the moisture penetration is almost impossible, moisture absorbents are used inside OLED. In this study, metal oxide/polymer hybrid nanofiber with mechanical flexibility and efficient moisture absorption capability was fabricated by electrospinning. Hydrophilic poly(vinyl pyrrolidone) (PVP) or hydrophobic poly(vinylidenefluoride) (PVDF) and calcium oxide (CaO) were used as the fiber forming polymers and as the moisture absorbing particle, respectively. Polymers were first dissolved in appropriate solvents and CaO was then dispersed in the prepared polymer solutions. The hybrid solution was then electrospun, producing the hybrid nanofiber web looking like paper with thickness of about 100 µm. It was observed that all CaO particles were uniformly held by the nanofiber. It was also observed that only a small portion of the surface of CaO particles was covered by fiber since the fiber diameter was much smaller than the CaO particle size. This implied effective moisture absorption through the free surface of CaO. The hybrid nanofiber absorbed moisture very efficiently upto about 70 % of the nanofiber mass. Once moisture was absorbed by the nanofiber, it was never released even at 150 °C in vacuum for 2 hours. It is, therefore, expected that the nanofiber may be applied as the flexible thin moisture absorbent to improve stability of the flexible OLED. 相似文献
160.