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Intranasal immunization with a peptide conjugated to Salmonella flagellin induces both systemic and mucosal peptide‐specific antibody responses in mice 下载免费PDF全文
Feng Qian Jian Yin Mengmeng Li Ting Li Ling Zhou Xin Wu Huji Xu 《Microbiology and immunology》2016,60(7):497-500
In this study, the mucosal adjuvant activity of Salmonella flagellin as a carrier in a conjugate of EXP153–rFliC was investigated. EXP153–rFliC was made by conjugation of a synthetic B‐cell epitope peptide derived from Plasmodium falciparum exported protein‐1(EXP153) to recombinant phase 1 flagellin of Salmonella enterica serovar Typhimurium expressed in Escherichia coli (rFliC), and used to immunize BALB/c mice via intranasal instillation. It was found that robust EXP153‐specific serum IgG antibodies were induced without additional adjuvant. EXP153‐specific sIgA antibodies were also induced, these being detected in bronchoalveolar, nasal, vaginal and intestinal washes. These observations demonstrate that Salmonella flagellin as a carrier is an effective mucosal adjuvant in that its conjugated peptide induces antibody responses. 相似文献
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Financial markets are partially composed of sectors dominated by external driving forces, such as commodity prices, infrastructure and other indices. We characterize the statistical properties of such sectors and present a novel model for the coupling of the stock prices and their dominating driving forces, inspired by mean reverting stochastic processes. Using the model we were able to explain the market sectors’ long term behavior and estimate the coupling strength between stocks in financial markets and the sector specific driving forces. Notably, the analysis was successfully applied to the shipping market, in which the Baltic dry index (BDI), an assessment of the price of transporting the major raw materials by sea, influences the shipping financial market. We also present the analysis of other sectors—the gold mining market and the food production market, for which the model was also successfully applied. The model can serve as a general tool for characterizing the coupling between external forces and affected financial variables and therefore for estimating the risk in sectors and their vulnerability to external stress. 相似文献
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采用6种不同的培养基,分别于25℃、32℃、42℃以及50℃培养分离从而对某一中国白酒酒曲中的丝状真菌菌群进行研究.从酒曲中共分离得到886株丝状真菌,分属于接合菌,子囊菌和无性型真菌的20属,45种.其中最为丰富的是无性型真菌(28种),其次是接合菌(10种)和子囊菌(7种).对发酵起主要作用的为那些嗜热和耐热的种属,包括:宛氏拟青霉,伞枝梨头霉,梳棉状嗜热丝孢菌,微小根毛霉,金孢霉属一种和红曲属的几个种.文中还对一些在发酵中起重要作用的丝状真菌的特性进行了探讨. 相似文献
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An IL-13 Promoter Polymorphism Associated with Liver Fibrosis in Patients with Schistosoma japonicum
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Loss of function of OsDCL1 affects microRNA accumulation and causes developmental defects in rice 总被引:7,自引:0,他引:7 下载免费PDF全文
MicroRNAs (miRNAs) and small interfering RNAs (siRNAs) are two types of noncoding RNAs involved in developmental regulation, genome maintenance, and defense in eukaryotes. The activity of Dicer or Dicer-like (DCL) proteins is required for the maturation of miRNAs and siRNAs. In this study, we cloned and sequenced 66 candidate rice (Oryza sativa) miRNAs out of 1,650 small RNA sequences (19 to approximately 25 nt), and they could be further grouped into 21 families, 12 of which are newly identified and three of which, OsmiR528, OsmiR529, and OsmiR530, have been confirmed by northern blot. To study the function of rice DCL proteins (OsDCLs) in the biogenesis of miRNAs and siRNAs, we searched genome databases and identified four OsDCLs. An RNA interference approach was applied to knock down two OsDCLs, OsDCL1 and OsDCL4, respectively. Strong loss of function of OsDCL1IR transformants that expressed inverted repeats of OsDCL1 resulted in developmental arrest at the seedling stage, and weak loss of function of OsDCL1IR transformants caused pleiotropic developmental defects. Moreover, all miRNAs tested were greatly reduced in OsDCL1IR but not OsDCL4IR transformants, indicating that OsDCL1 plays a critical role in miRNA processing in rice. In contrast, the production of siRNA from transgenic inverted repeats and endogenous CentO regions were not affected in either OsDCL1IR or OsDCL4IR transformants, suggesting that the production of miRNAs and siRNAs is via distinct OsDCLs. 相似文献