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Marek's disease (MD), an immunosuppressive disease induced by Marek's disease virus (MDV), provides an ideal model for studying diseases caused by a carcinogenic virus. CD79Bis a B-cell antigen receptor complex-associated protein β-chain precursor which is involved in the activation, proliferation, differentiation of B-cell and the transmission of downstream signals. This study analyzed CD79Bgene mRNA expression and methylation by two schemes #20 (5´ flanking to intron 1) and #27 (intron 2 to intron 3), between MDV-infected tumorous spleens (TS) and non-infected spleens (NS). Results showed that average methylation levels of CpGs in #20 and #27 were higher in TS than in NS (P<0.05), while, CD79BmRNA expression was lower in TS than in NS (P<0.01). Six of 40 CpG sites showed significantly (P<0.05) different methylation levels between TS and NS. Correlation analysis showed that the average methylation level rather than a single site methylation level in #20 affected (P<0.05) mRNA expression. Collectively, it was found that the change of CD79Bgene expression after MDV infection might be partly explained by modification of DNA methylation.

Marek's disease (MD), a highly cell-associated and contagious disease of chickens caused by Marek's disease virus (MDV) can result in neural lesions, immunosuppression and neoplasia in chicken. The Meq gene is an important oncogene in the MDV genome, and it is expressed highly in MD tumor tissues and MD T-lymphoblastoid cell lines. An experiment was conducted to elucidate the role of Meq in MD tumor transformation. RNA interference technology was used to block its expression, and then analyzed the biological effects of Meq knockdown on the MD tumor cell line MSB1. A small interfering RNA with an interference efficiency of 70% (P<0.01) was transfected into MSB1 cells to knock down the expression of Meq gene. The cell proliferation, cycle and apoptosis were detected post-Meq knockdown. The results showed that MSB1 cell proliferation was downregulated remarkably at 48 h (P<0.01), 60 h (P<0.05) and 72 h (P<0.01) post-Meq knockdown. The cell cycle was unaffected (P>0.05). B-cell lymphoma 2 gene (BCL2) was anti-apoptotic and caspase-6 was the effector in the apoptosis pathway. The activity of caspase-6 was upregulated (P<0.05) significantly and BCL2 gene expression was downregulated (P<0.05) significantly post-Meq knockdown, suggesting cell apoptosis might be induced. MSB1 cell migration did not exhibit any obvious change (P>0.05) post-Meq knockdown, but the expression of two genes (matrix metalloproteinase 2 (MMP2) and MMP9) that are correlated closely to cell invasion was downregulated (P<0.05) remarkably post-Meq knockdown. The Meq knockdown might affect the main features of tumorous cells, including proliferation, apoptosis, and invasion, suggesting that the Meq gene might play a crucial role in interfering with lymphomatous cell transformation.

To understand the effect of nitrogen (N) fertilizer on rice (Oryza sativaL.) eating and cooking quality (ECQ). Here, we investigated the ECQ attributes, physicochemical foundation of ECQ, and amylopectin fine structure of two Waxy(Wx) alleles japonicarice cultivars Nanjing 9108 (NJ9108) and Huaidao 5 (HD5) under four N rates (0, 150, 300, and 450 kg ha−1). Sensory and pasting properties of the two cultivars varied depending on N rates. Compared with the control (0 kg ha−1), the overall eating quality and sensory value were significantly decreased under the N rates of 300 and 450 kg ha−1. Further, conventional descriptive analysis showed that the stickiness and retrogradation of cooked rice were significantly decreased. These results indicated that application of N fertilizer seems to affect the texture of cooked rice, causing it to be less sticky, lowering its retrogradation, and consequently reducing its palatability. Results from rapid visco analyzer (RVA) revealed that the peak and breakdown viscosities significantly decreased, while the setback viscosity and peak time increased under the N rates of 300 and 450 kg ha−1. However, no significant difference was observed when the N rate was 150 kg ha−1, indicating that less N fertilization can maintain rice ECQ. As the N rate increasing, protein content increased, whereas apparent amylose content, starch content, and gel consistency almost unchanged. Interestingly, compared with the control, under N treatments, the percentage of short amylopectin branches in NJ9108 was decreased, but increased in HD5, as controlled by amylopectin synthesis-related genes. Notably, SSIand BEIIbwere down-regulated in NJ9108, whereas BEIIbwas up-regulated in HD5. Thus, the palatability of both rice cultivars was significantly decreased under excessive N fertilization as a consequence of reduced stickiness and retrogradation of the cooked rice, which might have resulted from an elevated protein content and altered amylopectin fine structure. In addition, amylopectin synthesis appeared to be affected by N fertilizer and the genotype of the rice cultivar.

In the paper, a velocity and fluid flow status of the melting process in twin-screw extruder were analyzed. To explore the optimum producing parameters of expanding food, several models of the flow field and velocity of twin-screw extruder were created with fake plastic Newton fluid. Then the velocity distribution rules in the cavity space were simulated. With the valuable verification of experiments, the results showed that, the velocity distribution near the inner wall is uniform, and increases at the delivery of the extruder. The velocity rises in the teeth root than in the top of the screws. At the mesh field, the velocity was changed frequently. The experiment of popped extrusion verified the simulation conclusion.

Three-dimensional model of the parts of the extrusion extruder for leisure food is created as an illustrator, which could be adopted up to form an assemble facility to the whole set of the machine conveniently by a software of SolidWorks in the paper.Some key specific modeling procedures are proved to show the advantages of Solidworks overweigh AutoCAD in three-dimensional modeling technology. The method put an adaptable way to short the whole lifetime of industrial product design.