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To investigate the molecular mechanism of silkworm resistance to BmNPV infection, we constructed a near-isogenic line (BC8) with BmNPV resistance using highly resistant (NB) and highly susceptible parental strains (306). We investigated variations in the gene expression in the midguts of BmNPV-infected BC8 and 306 at 12 h pi using the microarray. 92 differentially expressed genes were identified. Real-time qPCR analysis confirmed that 10 genes were significantly up-regulated or down-regulated in the midguts of BC8 and NB compared to 306. To our knowledge, we first defined the role of the amino acid transporter and 26S proteasome in insect antiviral. However, serine protease was not completely consistent with data of reported previously in insect antiviral. The role of the 5 genes (Bm123, Bm122, COP β′, aquaporin, glycoside hydrolases) was also demonstrated in insect antiviral. Our results provided new insights into the molecular mechanism of the Bombyx mori immune response against BmNPV infection.  相似文献   
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In this article, surface coatings derived from homo-bifunctional tri(ethylene glycol) (EG3) and hexa(ethylene glycol) (EG6) molecules which have two terminal aldehyde groups are reported. These homo-bifunctional molecules can be used to functionalize amine-terminated surfaces through crosslinking one aldehyde group to surface amine groups, while leaving the other aldehyde group available for covalent immobilization of proteins. Best of all, after reducing remaining aldehyde groups on the surface with a reducing agent, sodium borohydride, the surface becomes oligo(ethylene glycol) (OEG)-terminated. The OEG-terminated surface can resist nonspecific protein adsorption, a feature that is often required for many biosensors and biomedical devices. Although some mixed self-assembled monolayers formed from two different organothiols also permit covalent protein immobilization and resist nonspecific protein adsorption, the procedure reported herein requires only one type of homo-bifunctional molecule and can be applied to both silicon and gold surfaces.  相似文献   
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One mineral-solubilizing bacterial strain designated KT was isolated from a soil in Henan Province, China. The full-length 16S rRNA gene sequence showed 95.2 to 96.7% similarity to the bacteria of the genus Paenibacillus, indicating that the strain KT belonged to the genus Paenibacillus. The potential of this strain to release potassium from silicate minerals was investigated using a potassium-bearing rock as the sole source of potassium to support its growth. After inoculation for 7 days, the concentrations of water-soluble Al, Ca and Fe released from the potassium-bearing rock in active bacterial culture were higher than those from the control with autoclaved inoculum, but the concentration of water-soluble K in active bacterial culture was similar to that in the control. The concentrations of HNO3-extractable Al, Ca, Fe and K from the bacterial culture were also higher than those in the control. These results showed strain KT was able to release potassium from potassium-bearing rock. These results have important implications for extraction of potassium from rocks to support plant growth.  相似文献   
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The objective of this study was to analyze bacterial diversity in two different concrete samples to understand the dominant types of bacteria that may contribute to concrete corrosion. Two concrete samples, HN-1 from the sunny side and HN-2 from dark and damp side, were collected from Zijin Mountain in Nanjing and genomic DNA was extracted. The partial bacterial 16S rRNA gene fragment was PCR amplified and two clone libraries were constructed. Amplified ribosomal DNA restriction analysis (ARDRA) was performed by digestion of the 16S rRNA gene and each unique restriction fragment polymorphism pattern was designated as an operational taxonomic unit (OTU). Phylogenetic trees of bacterial 16S rDNA nucleotide sequences were constructed. Sample HN-1 and HN-2 contained 21 OTUs and 26 OTUs, respectively. Proteobacteria and Planctomycetes were the predominant bacteria in both samples, and they are distributed among Herbaspirillum, Archangium, Phyllobacteriaceae and Planctomycetaceae. Cyanobacteria and Rubrobacter sp. are dominant in HN-1; while Acidobacteriaceae, Adhaeribacter sp. and Nitrospira sp. are predominant in HN-2. This distribution pattern was consistent with local environmental conditions of these two samples. The inferred physiological characteristics of these bacteria, based on relatedness of the DNA clone sequences to cultivated species, revealed different mechanisms of concrete corrosion depending on the local environmental conditions.  相似文献   
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The non‐selective cationic transient receptor canonical 6 (TRPC6) channels are involved in synaptic plasticity changes ranging from dendritic growth, spine morphology changes and increase in excitatory synapses. We previously showed that the TRPC6 activator hyperforin, the active antidepressant component of St. John's wort, induces neuritic outgrowth and spine morphology changes in PC12 cells and hippocampal CA1 neurons. However, the signaling cascade that transmits the hyperforin‐induced transient rise in intracellular calcium into neuritic outgrowth is not yet fully understood. Several signaling pathways are involved in calcium transient‐mediated changes in synaptic plasticity, ranging from calmodulin‐mediated Ras‐induced signaling cascades comprising the mitogen‐activated protein kinase, PI3K signal transduction pathways as well as Ca2+/calmodulin‐dependent protein kinase II (CAMKII) and CAMKIV. We show that several mechanisms are involved in TRPC6‐mediated synaptic plasticity changes in PC12 cells and primary hippocampal neurons. Influx of calcium via TRPC6 channels activates different pathways including Ras/mitogen‐activated protein kinase/extracellular signal‐regulated kinases, phosphatidylinositide 3‐kinase/protein kinase B, and CAMKIV in both cell types, leading to cAMP‐response element binding protein phosphorylation. These findings are interesting not only in terms of the downstream targets of TRPC6 channels but also because of their potential to facilitate further understanding of St. John's wort extract‐mediated antidepressant activity.

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