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51.
红火蚁Solenopsis invicta Buren是一种国际重大外来入侵生物,严重危害农林生产、生命健康、公共安全和生态环境。本研究在室内条件下测定了小卷蛾斯氏线虫Steinernema carpocapsae All品系、长尾斯氏线虫S. longicaudum X-7品系和芫菁夜蛾斯氏线虫S. feltiae SN品系对红火蚁的致病力,并筛选出高致病力品系及其对红火蚁的田间防控效果。结果表明,不同昆虫病原线虫对红火蚁不同虫态的致病力存在显著差异。3种线虫对红火蚁幼虫具有较高的致病力,处理3 d后,幼虫的累计校正致死率均为100%。3种线虫对工蚁的致病力均较弱,处理10 d后的校正死亡率均小于30%。与芫菁夜蛾斯氏线虫SN品系相比,长尾斯氏线虫X-7品系和小卷蛾斯氏线虫All品系对蛹和生殖蚁具有较强的致病能力,10 d后累计校正死亡率均达到90%以上。田间试验表明,施用小卷蛾斯氏线虫All品系对红火蚁工蚁的防控效果最高可达63.7%,且不会增加红火蚁的迁巢风险。综上所述,小卷蛾斯氏线虫All品系和长尾斯氏线虫X-7品系为红火蚁的高致病品系,田间施用小卷蛾斯氏线虫All品系对红火蚁工蚁具有显著的控制作用,可推荐用于红火蚁的生物防治。 相似文献
52.
ChaoChien Chang KeeChin Sia JiaFeng Chang ChiaMo Lin ChuenMao Yang ITa Lee Thi Thuy Tien Vo KuoYang Huang WeiNing Lin 《Journal of cellular and molecular medicine》2022,26(14):3850
Obesity is a world‐wide problem, especially the child obesity, with the complication of various metabolic diseases. Child obesity can be developed as early as the age between 2 and 6. The expansion of fat mass in child age includes both hyperplasia and hypertrophy of adipose tissue, suggesting the importance of proliferation and adipogenesis of preadipocytes. The changed composition of gut microbiota is associated with obesity, revealing the roles of lipopolysaccharide (LPS) on manipulating adipose tissue development. Studies suggest that LPS enters the circulation and acts as a pro‐inflammatory regulator to facilitate pathologies. Nevertheless, the underlying mechanisms behind LPS‐modulated obesity are yet clearly elucidated. This study showed that LPS enhanced the expression of cyclooxygenase‐2 (COX‐2), an inflammatory regulator of obesity, in preadipocytes. Pretreating preadipocytes with the scavenger of reactive oxygen species (ROS) or the inhibitors of NADPH oxidase or p42/p44 MAPK markedly decreased LPS‐stimulated gene expression of COX‐2 together with the phosphorylation of p47phox and p42/p44 MAPK, separately. LPS activated p42/p44 MAPK via NADPH oxidase‐dependent ROS accumulation in preadipocytes. Reduction of intracellular ROS or attenuation of p42/p44 MAPK activation both reduced LPS‐mediated COX‐2 expression and preadipocyte proliferation. Moreover, LPS‐induced preadipocyte proliferation and adipogenesis were abolished by the inhibition of COX‐2 or PEG2 receptors. Taken together, our results suggested that LPS enhanced the proliferation and adipogenesis of preadipocytes via NADPH oxidase/ROS/p42/p44 MAPK‐dependent COX‐2 expression. 相似文献
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54.
M W Wong C B Xia M L Chen C X Zhang P S Mao G Q Nei Y Hosaka 《Japanese journal of medical science & biology》1988,41(1):31-36
Molluscicidal activity of B-2 (sodium 2,5-dichloro-4-bromophenol; called as Phebrol and registered in WHO as OMS 3012) was evaluated in a laboratory and the field trials were performed in two different localities in Yueyang city, China, for control of Oncomelania hupensis. B-2 was effective against O. hupensis both in the laboratory and in the field. A dosage of 50 g/m2 in 10% granular form or 20 ml/m2 in 25% liquid form of B-2 would be recommendable as a standard mollusciciding dose for control of O. hupensis. 相似文献
55.
miR164c and miR168a regulate seed vigor in rice 总被引:1,自引:0,他引:1
Yan Zhou Shiqi Zhou Liping Wang Duo Wu Hailan Cheng Xu Du Dandan Mao Chunlai Zhang Xiaocheng Jiang 《植物学报(英文版)》2020,62(4):470-486
56.
Mao Yingyan Yang Diya Li Jing Liu Jun Hou Ruowu Zhang Zheng Yang Yiquan Tian Lei Weinreb Robert N. Wang Ningli 《中国科学:生命科学英文版》2020,63(12):1887-1894
Science China Life Sciences - The present study aims to assess the potential difference of biomechanical response of the optic nerve head to the same level of trans-lamina cribrosa pressure... 相似文献
57.
Jiayan Li Daiwen Chen Bing Yu Jun He Zhiqing Huang Xiangbing Mao Ping Zheng Jie Yu Junqiu Luo Gang Tian Yuheng Luo 《Microbial biotechnology》2020,13(2):509-521
Despite their important roles in host nutrition and metabolism, and potential to cause disease, our knowledge of the fungal community in the mammalian gut is quite limited. To date, diversity and composition of fungi in swine gut still remains unknown. Therefore, the first internal transcribed spacer of fungi in faecal samples from three breeds of pigs (10 pigs for each breed) was sequenced based on an Illumina HiSeq 2500 platform, and the relationship between the fungal community and the concentrations of main short-chain fatty acids (SCFAs) was also analysed. Results indicated that Chenghua (local, higher body fat rate), Yorkshire (foreign, higher lean meat and growth rate) and Tibetan (plateau, stronger disease resistance) pigs harboured distinct fungal community. The Basidiomycota and Ascomycota presented as the two predominant phyla, with Loreleia, Russula and Candida as the top three genera in all samples. Network analysis revealed a total of 35 correlations among different fungal genera, with 27 (77.14%) positive and 8 (22.86%) negative pairwise interactions. Canonical correspondence analysis suggested that fungi in the faeces of pigs were more correlated to the concentration of acetate and butyrate rather than propionate. Spearman’s correlation further showed that Tomentella was positively correlated to both acetate and butyrate, and Loreleia was positively correlated to propionate (P < 0.05), while Nephroma and Taiwanofungus were negatively correlated to acetate and propionate (P < 0.05). These findings expanded our knowledge on the intestinal fungi in pigs with different genotypes and phenotypes, indicating that fungi may play an indispensable role during the metabolism of host and the maintenance of intestinal health. The cross-feeding between fungi and other microorganisms may be crucial during the digestion of dietary carbohydrates and the associated physiological processes, which is worthy to be further studied. 相似文献
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59.
Haiping Zhang Bailian Cai Anke Geng Huanyin Tang Wenjun Zhang Sheng Li Ying Jiang Rong Tan Xiaoping Wan Zhiyong Mao 《Aging cell》2020,19(2)
The decline in DNA repair capacity contributes to the age‐associated decrease in genome integrity in somatic cells of different species. However, due to the lack of clinical samples and appropriate tools for studying DNA repair, whether and how age‐associated changes in DNA repair result in a loss of genome integrity of human adult stem cells remains incompletely characterized. Here, we isolated 20 eyelid adipose‐derived stem cell (ADSC) lines from healthy individuals (young: 10 donors with ages ranging 17–25 years; old: 10 donors with ages ranging 50–59 years). Using these cell lines, we systematically compared the efficiency of base excision repair (BER) and two DNA double‐strand break (DSB) repair pathways—nonhomologous end joining (NHEJ) and homologous recombination (HR)—between the young and old groups. Surprisingly, we found that the efficiency of BER but not NHEJ or HR is impaired in aged human ADSCs, which is in contrast to previous findings that DSB repair declines with age in human fibroblasts. We also demonstrated that BER efficiency is negatively associated with tail moment, which reflects a loss of genome integrity in human ADSCs. Mechanistic studies indicated that at the protein level XRCC1, but not other BER factors, exhibited age‐associated decline. Overexpression of XRCC1 reversed the decline of BER efficiency and genome integrity, indicating that XRCC1 is a potential therapeutic target for stabilizing genomes in aged ADSCs. 相似文献
60.
Dingqian Wu Xiaoxiao Fu Yuanyuan Zhang Qiang Li Ligang Ye Shu Han Mao Zhang 《Experimental biology and medicine (Maywood, N.J.)》2020,245(18):1683
C16 peptide and angiopoietin-1 (Ang-1) have been found to have anti-inflammatory activity in various inflammation-related diseases. However, their combined role in acute respiratory distress syndrome (ARDS) has not been investigated yet. The objective of this study was to investigate the effects of C16 peptide and Ang-1 in combination with lipopolysaccharide (LPS)-induced inflammatory insult in vitro and in vivo. Human pulmonary microvascular endothelial cells and human pulmonary alveolar epithelial cells were used as cell culture systems, and an ARDS rodent model was used for in vivo studies. Our results demonstrated that C16 and Ang-1 in combination significantly suppressed inflammatory cell transmigration by 33% in comparison with the vehicle alone, and decreased the lung tissue wet-to-dry lung weight ratio to a maximum of 1.53, compared to 3.55 in the vehicle group in ARDS rats. Moreover, C + A treatment reduced the histology injury score to 60% of the vehicle control, enhanced arterial oxygen saturation (SO2), decreased arterial carbon dioxide partial pressure (PCO2), and increased oxygen partial pressure (PO2) in ARDS rats, while also improving the survival rate from 47% (7/15) to 80% (12/15) and diminishing fibrosis, necrosis, and apoptosis in lung tissue. Furthermore, when C + A therapy was administered 4 h following LPS injection, the treatment showed significant alleviating effects on pulmonary inflammatory cell infiltration 24 h postinsult. In conclusion, our in vitro and in vivo studies show that C16 and Ang-1 exert protective effects against LPS-induced inflammatory insult. C16 and Ang-1 hold promise as a novel agent against LPS-induced ARDS. Further studies are needed to determine the potential for C16 and Ang-1 in combination in treating inflammatory lung diseases. 相似文献