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91.
Zhao L Jin H She R Hu Y Xiao C Yu Y Wang J Sun F Ng T Chu S Wang B 《Veterinary immunology and immunopathology》2006,114(3-4):285-296
There have been very few reports of experimentally induced animal models of allergic dermatitis, an immunologic disorder. This report describes the induction of histopathology confirmed allergic dermatitis in C57BL/6 mice along with the consistent clinical sign of alopecia following the administration of flea antigens emulsified in complete Freund's adjuvant (CFA). By comparing different strains of mice, routes of injection, types of adjuvants and different dosages of flea antigens, C57BL/6 mice were found to be most susceptible to flea antigens administered intramuscularly (i.m.) and subsequently developed dermatologic excoriations and local alopecia. The level of specific IgE reactive to flea antigens in C57BL/6 mice after the onset of clinical signs was significantly higher than such levels in mice without clinical signs, suggesting that flea antigen-specific IgE level can be correlated to the severity of allergic hyper-reaction. CD4(+) T lymphocytes and IL-4 rather than IL-10, or IFN-gamma were found to be the predominant cytokines associated with the clinical onset of allergic symptoms in C57BL/6 mice. Further, histopathologic analysis indicated that not only mast cells had infiltrated into the area of the skin lesion, but the damage was found to be at a stage where mast cells were degranulating causing considerable exacerbation of the local injury. In conclusion, this murine allergic dermatitis model induced by flea antigens may provide a useful means to evaluate vaccines or immunodulatory drugs; thus providing researchers with a tool to study allergy-related disorders and other parameters needed in the area of allergic investigations. 相似文献
92.
Shih CH Siu SO Ng R Wong E Chiu LC Chu IK Lo C 《Journal of agricultural and food chemistry》2007,55(2):254-259
3-Deoxyanthocyanidins are structurally related to the anthocyanin pigments, which are popular as health-promoting phytochemicals. Here, it is demonstrated that the 3-deoxyanthocyanidins are more cytotoxic on human cancer cells than the 3-hydroxylated anthocyanidin analogues. At 200 microM concentration, luteolinidin reduced the viability of HL-60 and HepG2 cells by 90 and 50%, respectively. Sorghum is a major source of 3-deoxyanthocyanidins, which are present as seed pigments and as phytoalexins responding to pathogen attack. On the basis of the collision-induced dissociation spectra of luteolinidin and apigeninidin, an LC-MS/MS method, operating in multiple-reaction monitoring mode, was developed for the specific detection and accurate quantification of these compounds in complex mixtures, which may be difficult to analyze using absorbance measurements. The results demonstrated that inoculated sorghum seedlings could be utilized for convenient and large-scale production of 3-deoxyanthocyanidins. A quantity of almost 270 microg/g (fresh weight) of luteolinidin was produced 72 h after fungal inoculation of 1-week-old seedlings. 相似文献
93.
Water, Air, &; Soil Pollution - Amendment of simple organic carbon, in the presence of inorganic nutrients, to oil contaminated beach sediments can potentially stimulate the biodegradation of... 相似文献
94.
V. Lattanzio A. Cardinali V. Linsalata P. Perrino N. Q. Ng 《Genetic Resources and Crop Evolution》1996,43(6):493-504
Summary Flavonoid chemical markers together with other biochemical markers and/or morphological data can provide useful characters for defining species in Vigna genus. In this paper flavonid HPLC fingerprints have been utilized to assess taxonomic relationships amongst species and accessions of Vigna. Within the taxa analysed there is evidence of both infra- and interspecific chemical variations. In some species chromatographic data support evidence for the existence of different flavonoid chemotypes, which may reflect differences in geographic origin. As far as interspecific relationships are concerned, species belonging to sections Vigna, Plectotropis and Ceratotropis do not show flavonoid glycosides in common with cultivated lines of Vigna. By contrast, some relationships have been found between cultivated lines and wild species of section Catiang. Kaempferol-3-rutinoside and an unidentified kaempferol-glycoside were the only flavonoids detected in the three subgenera analysed. Finally, a greater variability in flavonoid aglycone class and glycosylation pattern has been observed in cultivars of V. unguiculata (L.) Walp. compared to the wild species. This observation may confirm that cultivation and/or domestication may cause or increase species diversification. 相似文献
95.
The application of magnetite-immobilized chitin in pentachlorophenol (PCP) removal was demonstrated in this study. The physicochemical parameters for immobilization of chitin by magnetite, and for PCP adsorption using magnetite-immobilized chitin were optimized. For chitin immobilization, the optimized conditions were: magnetite to chitin (m:c) ratio at 1:2, initial pH 6, 25°C, 200 rpm and 60 min in batch system. The immobilization efficiency (IE) was 99.4% and immobilization capacity (IC) was 2.0 mg chitin mg?1 magnetite. High initial pH (pH?>?11) and temperature (>30°C) lowered the IE and IC. For PCP (10 mg l?1) adsorption, the optimized conditions were: 1,500 mg l?1 immobilized chitin, initial pH 6, 25°C, 200 rpm and 60 min in batch system. The removal efficiency (RE) was 57.9% and removal capacity (RC) was 5.4 mg g?1. The adsorption ability of immobilized chitin decreased with pH and temperature increased. However, increasing the amount of immobilized chitin (24,000 mg l?1) can increase the RE up to 92%. Both chitin immobilization and PCP adsorption exhibited Langmuir and Freundlich adsorption isotherms. Results in this study indicated that magnetite-immobilized chitin was a cost-effective and environmental friendly adsorbent to remove environmental pollutants such as PCP. 相似文献
96.
Roads, especially large highways, can have significant impacts on wildlife movement and survival. This is especially true for wide-ranging species, such as mammalian carnivores. Some of these impacts may be mitigated if wildlife can find and utilize passageways under highways. To determine if underpasses and drainage culverts beneath highways are used by wildlife as movement corridors, we monitored 15 such passages near Los Angeles, California using remotely triggered cameras and gypsum track stations. We found that passages were used by a variety of species, including carnivores, mule deer, small mammals, and reptiles. Many types of undercrossings were utilized, indicating that passages beneath highways, even when not originally designed for wildlife, can provide important safe avenues for animals to cross roads. For mammals of conservation concern, including native carnivores and deer, passage dimensions, surrounding habitat, and the extent of human activity were assessed to determine if these factors influenced passage use by these species. Our results show that while many native mammals used passages beneath highways, the presence of suitable habitat on either side of the passage was a particularly important factor predicting use. For deer and coyotes, passage dimensions were also important and should be considered with the presence of suitable habitat when wildlife passages are planned or evaluated. To increase the likelihood of utilization and to help prevent animals from crossing road surfaces, we suggest that simple improvements such as habitat restoration near crossing points and animal-proof fencing that serves to funnel wildlife to passages, can facilitate animal movement between fragmented habitats that are bisected by roads. 相似文献
97.
98.
Large earthquakes occur episodically in the Cascadia subduction zone. A numerical model has been used to simulate and assess the hazards of a tsunami generated by a hypothetical earthquake of magnitude 8.5 associated with rupture of the northern sections of the subduction zone. Wave amplitudes on the outer coast are closely related to the magnitude of sea-bottom displacement (5.0 meters). Some amplification, up to a factor of 3, may occur in some coastal embayments. Wave amplitudes in the protected waters of Puget Sound and the Strait of Georgia are predicted to be only about one fifth of those estmated on the outer coast. 相似文献
99.
Ye XJ Ng TB Wu ZJ Xie LH Fang EF Wong JH Pan WL Wing SS Zhang YB 《Journal of agricultural and food chemistry》2011,59(18):10232-10238
A 30 kDa antifungal protein was purified from red cabbage ( Brassica oleracea ) seeds. It exhibited a molecular mass and N-terminal amino acid sequence disinct from those of previously isolated Brassica antifungal proteins. The protocol used entailed ion exchange chromatography on Q-Sepharose and SP-Sepharose followed by fast protein liquid chromatography on Mono S. The protein hindered mycelial growth in Mycosphaerella arachidicola (with an IC50=5 μM), Setospaeria turcica, and Bipolaris maydis. It also inhibited the yeast Candida albicans with an IC50=96 μM. It exerted its antifungal action by permeabilizing the fungal membrane as evidenced by staining with Sytox green. The antifungal activity was stable from pH 3 to 11 and from 0 to 65 °C. It manifested antibacterial activity against Pseudomonas aeruginosa (IC50=53 μM). Furthermore, after 48 h of culture, it suppressed proliferation of nasopharyngeal cancer and hepatoma cells with IC50=50 and 90 μM, respectively. 相似文献
100.
Bah CS Fang EF Ng TB Mros S McConnell M Bekhit Ael-D 《Journal of agricultural and food chemistry》2011,59(10):5720-5728
In this study, a rhamnose-binding lectin from the roe of chinook salmon (Oncorhynchus tshawytscha) was purified and characterized, and its biological activities were examined in several model systems. Chinook salmon roe lectin had a molecular mass of 30 kDa and agglutinated rabbit and bovine erythrocytes. The hemagglutination activity of the lectin was not affected by metal ions. The lectin was stable up to 70 °C and between pH 4 and pH 11. Chinook salmon roe lectin did not exert antifungal activity toward the fungal species tested and did not exhibit mitogenic response toward mouse splenocytes up to a concentration of 5 mg/mL. The lectin had selective antiproliferative activity toward human breast cancer MCF-7 cells and hepatoma Hep G2 cells. It also induced the production of nitric oxide from mouse peritoneal macrophages. This is the first report that demonstrates these biological activities from chinook salmon roe lectin. 相似文献