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1.
Wang Y Bai Y Qu Q Xu J Chen Y Zhong Z Qiu Y Wang T Du X Wang Z Yu S Fu S Yuan J Zhen Q Yu Y Chen Z Huang L 《Veterinary microbiology》2011,151(3-4):354-362
Brucellosis brings great economic burdens for developing countries. Live attenuated vaccines are the most efficient means for prevention and control of animal Brucellosis. However, the difficulties of differentiating of infection from vaccine immunization, which is essential for eradication programs, limit their applications. Therefore, the development of a vaccine that could differentiate infection from immunization will overcome the limitations and get extensive application. VjbR is a quorum sensing regulator involving in Brucella's intracellular survival. The vjbR∷Tn5 mutants have been proven effective against wild type strain challenge, implying its possibility of use in vaccine candidate development. To further evaluate this candidate gene, in the present study, the antigenicity of purified recombinant VjbR protein was analyzed. Antibodies to Brucella melitensis VjbR could be detected in sera from patients and animals with brucellosis but not in control ones, implying the potential use of this protein as a diagnostic antigen. Then a vjbR mutant of B. melitensis 16M was constructed by replacing the vjbR with kanamycin gene. The mutant showed reduced survival in macrophage and mice. Vaccination of BALB/c mice with 16MΔvjbR conferred significant protective immunity against B. melitensis strain 16M challenges, being equivalent to which induced by the license vaccine Rev.1. The vjbR deletion mutant elicited an anti-Brucella-specific immunoglobulin G response and induced the secretion of gamma interferon and interleukin-10. The most importance is that, the use of vjbR mutants as vaccines in association with diagnostic tests based on the VjbR antigen would allow the serological differentiation between infected and vaccinated animals. These results suggest that 16MΔvjbR is an ideal live attenuated vaccine candidate against B. melitensis and deserves further evaluation for vaccine development. 相似文献
2.
3.
Du Hwan Chun 《Fibers and Polymers》2017,18(9):1790-1795
The numerical analysis was performed to predict the potential problem, often occurring during the manufacturing process of the disposable medical device of a great volume. The cavity filling analyses were performed for the new design of the 3cc Syringe Barrel using polypropylene(PP1), and a new nucleated polypropylene(PP2) material for better clarity. These analyses have been performed for different processing conditions as well as various wall thickness designs for both materials. With the nucleated material, only the original wall thickness design has been studied at two different processing conditions for comparison purpose. This study was conducted to investigate the optimum part design and processing condition for two different materials. The most desirable design was selected with Design 3 for material utilization and reduced flow stresses by comparing the field results. The new nucleated polypropylene provided slightly better product quality and processing. 相似文献
4.
ACC合酶cDNA克隆及其对美洲黑杨体内乙烯产生的反义抑制 总被引:1,自引:0,他引:1
利用RTPCR技术克隆了大豆ACC合酶基因GMCACCSI编码区15kb的cDNA片段,经酶切图谱分析和序列分析鉴定后,反向插入到2元载体pBin438中,构建了表达ACC合酶反义RNA的植物表达载体,转化农杆菌后用该农杆菌侵染美洲黑杨叶片,在含卡那霉素的MS培养基上选择转化子和植株再生,通过PCR检测从抗卡那植株中选到15株转基因植株,Southern杂交分析初步确证了外源基因是以单拷贝插入到杨树基因组DNA中;对杨树幼苗乙烯释放的测定结果表明转基因杨树幼苗的乙烯释放量为对照的22%。 相似文献
5.
6.
Cristina E. Almeida-Naranjo Patricio J. Espinoza-Montero Marcelo I. Muñoz-Rodríguez Cristina A. Villamar-Ayala 《Water, air, and soil pollution》2017,228(7):253
Hydraulic retention time (HRT) influence improving sludge flocculation with adding the polyelectrolytes (non-ionic, anionic, and cationic) was studied on an activated sludge (AS) system fed with synthetic domestic wastewater (SDW), dairy industry wastewater (DIW), and caramel industry wastewater (CIW). The sludge volumetric index, food/microorganism ratio (F/M), and mixed liquor volatile suspended solids at different HRTs (6, 8 and 10 h) were monitored on an experimental model. Results showed that both SDW and IW had the best sludge flocculation conditions at 8 h and 100 mL of non-ionic polyelectrolyte (0.2 mg L?1). In addition, this phenomenon reached the organic matter removal efficiencies of 95.9, 95.7, and 94.2% for SDW, DIW, and CIW, respectively. Therefore, optimum HRT increased the organic matter removal efficiencies by 10%, sludge concentration by 37% (22–55%), and F/M ratio by 70%. Moreover, the polyelectrolytes used in AS improved the sludge flocculation by 2.9 times. 相似文献
7.
Stacy N. Galleher Matthew R. Gilg Kelly J. Smith 《Fish physiology and biochemistry》2010,36(3):731-740
Fundulus heteroclitus and F. grandis are resident salt marsh fishes that overlap in distribution over a narrow range in northeastern Florida. The objective of
the present study was to examine whether the limits of the species’ ranges could be explained by differences in thermal tolerance.
Two populations of each species were collected and then spawned in the laboratory, and 9-day-old larvae were used for critical
thermal maxima trials. Mean LOE temperatures of larvae ranged from 43.04 to 43.65°C and showed little difference between species.
Therefore, differences in high temperatures experienced cannot account for the differences of the distributions of the two
species. Condition-specific competition may play a greater role in determining the observed range of the two species. 相似文献
8.
During three consecutive seasons, two different deficit irrigation strategies were compared with control fully irrigated trees
regarding their capacity to induce early bloom and harvest in “Algerie” loquat. The first strategy, a continuous deficit irrigation
strategy, consisted in a uniform reduction of 20% water needs through the entire season; the second strategy, a regulated
deficit irrigation approach, while accounting for the same global reduction of 20% loquat water needs, concentrated water
shortages after harvest from mid-May through the end of August. Regulated deficit irrigation resulted more successful. Postharvest
regulated deficit irrigation advanced full bloom 10–20 days depending on the season. Such enhancement led to more precocious
and valuable yield, with an average increase of fruit value of 0.21 € kg−1. The effects of continuous deficit irrigation were less noticeable and average fruit value was increased 0.08 € kg−1. Yield and fruit quality were not affected for the different deficit irrigation strategies. Water savings established around
1450 m3 ha−1 year−1. Deficit irrigation rose water use efficiency up to more than a 40%. 相似文献
9.
研究了芦荟凝胶在制汁过程及芦荟饮料在加工过程中温度和时间等因数对芦荟饮料色泽的影响。结果表明,搅汁时间10min,杀菌温度85℃,杀菌时间25min是有效控制芦荟饮料褐变的最佳工艺参数。 相似文献
10.
Ayu-Lana-Nafisyah Endang-Dewi-Masithah Kazumi Matsuoka Mirni-Lamid Mochammad-Amin-Alamsjah Shizuka O-hara Kazuhiko Koike 《Fisheries Science》2018,84(5):877-887
Mangrove forests and adjacent creeks are known to be highly productive estuaries, which are partly supported by benthic microalgae that grow on the sediments. During surveys investigating the microalgal floras of mangrove swamps in the eastern part of Java Island, a mud sample unexpectedly included large numbers of a notorious fish killer, Chattonella-like motile cells, and its resting cysts. These motile cells were established as clonal cultures for further identification and physiological tests. The cysts were examined through palynological and molecular biological means. Identification based on light microscopy and ribosomal RNA gene sequences confirmed that these cells and cysts were Chattonella marina var. marina. While the strains were genetically identical to the temperate strains isolated from Japan and China, temperature experiments showed that the Indonesian strains possessed a high maximum quantum yield of photosystem II even after exposure to 34 °C, a temperature at which the Japanese strain could not survive. Salinity experiments showed adaptation of the strains to a salinity of 15. These findings, together with the discovery of populations of cysts in the mangrove sediment, highlight the tough and unique nature of the Indonesian strains, which are likely adapted to wide fluctuations of temperature and salinity in mangrove swamps, and pose a potential risk to fisheries in Indonesia. 相似文献