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191.
Ye Wang Yong-Hui Xie Qin-Hong Jiang Hong-Tao Chen Rui-Hao Ma Zhi-Jiang Wang Mei-Zhen Yin Jie Shen Shuo Yan 《Insect Science》2023,30(1):2-14
The unscientific application of synthetic pesticides has brought various negative effects on the environment, hindering the sustainable development of agriculture. Nanoparticles can be applied as carriers to improve pesticide delivery, showing great potential in the development of pesticide formulation in recent years. Herein, a star polymer (SPc) was constructed as an efficient pesticide nanocarrier/adjuvant that could spontaneously assemble with thiocyclam or monosultap into a complex, through hydrophobic association and hydrogen bonding, respectively, with the pesticide-loading contents of 42.54% and 19.3%. This complexation reduced the particle sizes of thiocyclam from 543.54 to 52.74 nm for pure thiocyclam, and 3 814.16 to 1 185.89 nm for commercial preparation (cp) of thiocyclam. Interestingly, the introduction of SPc decreased the contact angles of both pure and cp thiocyclam on plant leaves, and increased the plant uptake of cp thiocyclam to 2.4–1.9 times of that without SPc. Meanwhile, the SPc could promote the bioactivity of pure/cp thiocyclam against green peach aphids through leaf dipping method and root application. For leaf dipping method, the 50% lethal concentration decreased from 0.532 to 0.221 g/L after the complexation of pure thiocyclam with SPc, and that decreased from 0.390 to 0.251 g/L for cp thiocyclam. SPc seems a promising adjuvant for nanometerization of both pure and cp insecticides, which is beneficial for improving the delivery efficiency and utilization rate of pesticides. 相似文献
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Xinyue Ye Jian Wang Pengfei Xu Xiaoqian Yang Qixue Shi Genyan Liu Zhaoshi Bai Changlin Zhou Lingman Ma 《Microbial biotechnology》2023,16(9):1755-1773
Polymyxin resistance is conferred by MCR-1 (mobile colistin resistance 1)-induced lipopolysaccharide (LPS) modification of G− bacteria. However, the peptide MSI-1 exerts potent antimicrobial activity against mcr-1-carrying bacteria. To further investigate the potential role of MCR-1 in improving bacterial virulence and facilitating immune evasion, and the immunomodulatory effect of peptide MSI-1, we first explored outer membrane vesicle (OMV) alterations of mcr-1-carrying bacteria in the presence and absence of sub-MIC MSI-1, and host immune activation during bacterial infection and OMV stimulation. Our results demonstrated that LPS remodelling induced by MCR-1 negatively affected OMV formation and protein cargo by E. coli. In addition, MCR-1 diminished LPS-stimulated pyroptosis but facilitated mitochondrial dysfunction, further aggravating apoptosis in macrophages induced by OMVs of E. coli. Similarly, TLR4-mediated NF-κB activation was markedly alleviated once LPS was modified by MCR-1. However, peptide MSI-1 at the sub-MIC level inhibited the expression of MCR-1, further partly rescuing OMV alteration and attenuation of immune responses in the presence of MCR-1 during both infection and OMV stimulation, which can be exploited for anti-infective therapy. 相似文献
194.
Jia-Xing Fang Da-Feng Chen Xia Shi Su-Fang Zhang Fu Liu Wei-Xing Shen Chun-Yan Jia Shen-Cheng Ma Zhen Zhang Xiang-Bo Kong 《植物分类学报:英文版》2023,61(3):498-505
Cuticular hydrocarbons of Cerambycidae species can function as signals for sex recognition. Little is known about the copulatory signals of the juniper bark borer Semanotus bifasciatus, a major economic threat to Platycladus orientalis Franco in China. Here, we investigated the cuticular hydrocarbons of both sexes of S. bifasciatus to determine the chemically mediated mating signals using the solid-phase microextraction (SPME) technique with carbowax/divinylbenzene fibers (CAR/DVB) and then analyzed by coupled gas chromatography-mass spectrometry (GC-MS). A series of aliphatic saturated straight-chain n-alkanes (n-C23 to n-C28), internally branched monomethylalkanes at carbons 3, 11, or 13, and dimethylalkanes were identified, which showed no qualitative differences in either sex and were similar in the samples with SPME fiber extraction and those with hexane extraction. The bioassay showed that 11-methylpentacosane (11-MeC25), 11-methylhexacosane (11-MeC26), and 11-methylheptacosane (11-MeC27) have sex-specific recognition functions that triggered more mating attempts at a female-specific ratio of 100:4:60 than at a male-specific ratio of 100:85:50. In addition, the female-specific ratio of 11-methylalkanes can elicit about 70% of male mating attempts within about 60 s, whereas live females elicit about 98% of male mating attempts within 25 s. The discrepancy in the initiation of mating attempts by synthetic mixtures and live females suggests that the methyl isomers 3-MeC25, 3-MeC27, and/or 11,15-diMeC27 may also be involved in the mating behavior of S. bifasciatus. These results suggest that 11-MeC25, 11-MeC26, and 11-MeC27 constitute the contact sex pheromone of S. bifasciatus, with the presence or absence of 11-MeC26 in particular playing an important role in mate recognition by males. 相似文献
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采用垂直板聚丙烯酰胺凝胶电泳和紫外分光光度法分析大鲵15种组织的乳酸脱氢酶(LDH)同工酶后发现:在正常生理条件下,大鲵体内只有H4和M4两种同工酶,红细胞只有M4一种同工酶;大鲵体内LDH同工酶中,以M4占绝对优势;除生殖腺及脑外,在幼体至成体的发育过程中,LDH同工酶未见变化;大鲵体内各组织LDH含量及前述两种同工酶相对含量不同。 相似文献
200.
桃儿七分布格局与生态适应的初步研究 总被引:10,自引:0,他引:10
以云南产桃儿七Sinopodophyllum hexandrum(Royle)Ying为研究材料,分析了它的分布格局及生态适应。指出桃儿七是一个分布范围较广、生态适应幅度大的物种;在分布区内它主要出现在具有次生植被的山谷中,个体在居群内的分布格局,由于受到放牧活动的影响而呈聚群式分布,植株常出现在灌木丛下和树根附近。它适应夏秋湿润凉爽,冬季及早春寒冷干燥的气候条件,并具有相应的生长与发育节律。人类 相似文献