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Copyright of Chinese Journal of Pathophysiology is the property of Jinan University, School of Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To discuss the effect of Aspergillus fumigatus (Af) on DNA damage and interleukin (IL)-33 expression in the human bronchial epithelial cells, and to clarify its related mechanism. Methods: Different concentrations (1, 5, and 10 mg·L -1) of Af were used to stimulate the bronchial epithelial BEAS-2B cells to select the appropriate stimulation concentration. When the BEAS-2B cells were treated with N-acetylcysteine (NAC) and Af, the cells were divided into control group, Af group, NAC group, and Af+NAC group. When the BEAS-2B cells were treated with DNA double-strand break repair inhibitor NU7441 and Af, the cells were divided into control group, Af group, NU7441 group, and Af+NU7441 group. The comet assay was used to detect the percentages of comet tail DNA of cells in various groups; immunofluorescence method was used to detect the expression levels of DNA damage-related protein phosphorylated H2AX (γH2AX) in the cells in various groups; 2, 7-dichlorofluorescein diacetate (DCFH-DA) fluorescence probe was used to detect the levels of reactive oxygen species (ROS) in the cells in various groups; real-time fluorescence quantitative PCR (RT-qPCR) method was used to detect the expression levels of interleukih-33 (IL-33), thymic stromal lymphopoietin (TSLP), and interleukih-25 (IL-25) mRNA in the cells in various groups; Western blotting method was used to detect the expression levels of phosphorylated nuclear factor κB (p-NF-κB), phosphorylated ataxia telangiectasia mutated (p-ATM), and γH2AX proteins in the cells in various groups. Results: Compared with control group, the percentage of comet tail DNA and the expression level of γ H2AX in the cells in 1 mg·L-1 Af group showed no significant difference (P>0. 05), while the percentage of comet tail DNA and the expression level of γH2AX in the cells in 5 mg·L -1 Af group were significantly increased (P<0. 01); compared with 5 mg·L-1 Af group, the percentage of comet tail DNA and the expression level of γH2AX in the cells in 10 mg·L-1 Af group were significantly increased (P<0. 01). Compared with control group, the ROS levels in the bronchial epithelial cells in 1 mg·L-1 Af group was significantly increased (P< 0. 05); compared with 1 mg·L-1 Af group, the ROS level in the cells in 5 mg·L-1 Af group was significantly increased (P<0. 01); compared with 5 mg·L-1 Af group, the ROS level in the cells in 10 mg·L-1 Af group was significantly increased (P<0. 05). After treatment of NAC, compared with Af group, the percentage of comet tail DNA (P<0. 01), the expression level of γH2AX (P<0. 05), and the ROS level (P<0. 01) in the cells in Af+NAC group were significantly decreased; after treatment of NU7441, compared with Af group, the percentage of comet tail DNA and the expression level of γH2AX in the cells in Af+NU7441 group were significantly increased (P<0. 01). The RT-qPCR results showed that after treatment of NAC, compared with control group, the expression level of IL-33 mRNA in the cells in Af group was significantly increased (P<0. 05); compared with Af group, the expression level of IL-33 mRNA in the cells in Af+NAC group was significantly decreased (P<0. 05); after treatment of NU7441, compared with Af group, the expression level of IL-33 mRNA in the cells in Af+NU7441 group was significantly increased (P<0. 05). The Western blotting results showed that after treatment of NAC, compared with control group, the expression levels of p-NF-κB, p-ATM, and γH2AX proteins in the cells in Af group were significantly increased (P<0. 05); after treatment of NU7441, compared with Af group, the expression levels of p-NF- κB, p-ATM, and γH2AX proteins in the cells in Af+NAC group were significantly decreased (P<0. 05); After treat ment of NU7441, compared with Af group, the expression levels of p-NF- κB, p-ATM, and γH2AX proteins in the cells in Af+NU7441 group were significantly increased (P<0. 05). Conclusion: Af promotes the IL-33 expression in the human bronchial epithelial cells by causing DNA damage, and its mechanism may be related to the activation of ATM/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Directional seeding of corn seed can improve the light energy utilization of corn plants and the ventilated effect of field, which is of great significance to increase the corn yield per unit area. In order to realize directional seeding of corn seed, this study developed a kind of corn seed directional positioning machine based on image processing technology, and its main components included seed-metering device, conveying device, image acquisition and processing unit and directional positioning device. First, the compulsory clamp-type precision seed-metering device was chosen to complete seed feeding, and combined with the process of feeding seed when duckbilled seeding mouth was opened by roller, a guide-localization method was proposed for positioning process of seed onto conveyer belt. Based on this method, a kind of guide-localization tube was designed, and its structural dimension and installation position were determined through empirical analysis and theoretical calculation. And then the actual position distribution of corn seeds fed onto conveyer belt was acquired by the experiment. Also, locating notch of concave shape was designed to position seed by a mechanical way, and through speed and displacement analysis of each phase of seed positioning process, the conditions that seed could be positioned by locating notch effectively and continuously were obtained. At the same time, on the basis of previous studies, the image detection algorithm toward seed germ surface orientation and seed tip orientation of qualified seed was improved. In the end, the directional positioning device, the most important component of this machine, was developed with motors as rotary power. Location of seed was found according to image detection information as well as photoelectric positioning signal. After that, seed was grabbed by the way of suction to complete the following directional positioning work: On one hand, according to the image detection information about seed tip orientation, a specified motor drove a specified rotating mechanism of the machine to adjust seed tip orientation, which made seed towards the target direction; on the other hand, based on the image detection information about seed germ surface orientation, i.e. the front or the back, another specified motor drove another specified rotating mechanism of the machine to put seeds in 2 different positions located on each side of the machine. In addition, the required precision of revolving position was analyzed, and accordingly the positioning control mode was discussed and the corresponding operation parameters were set up. In the experiment, the results showed that the detection accuracy of germ surface orientation was 98%, the detection deviation of seed tip orientation was not more than 8°, the locating accuracy of concave notch was 97%, the locating and sucking accuracy of rotating arm was 94%, the locating accuracy of seed placing was 99%, and the angular deviation of seed placing was not more than 10°, which met the design requirements. If one viscous seed band is placed on each side of this machine, which is used to load seeds whose positioning and directing are completed and to make seeds stick on the seed bands evenly and orderly, it will provide condition and foundation for the subsequent directional packaging and seeding. [ABSTRACT FROM AUTHOR]