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991.
As a devastating holoparasitic weed, Orobanche aegyptiaca Persoon. (Egyptian broomrape) causes serious damage to agricultural production and threatens economic development, which has raised widespread concern. The present study was conducted to determine whether lilies have the potential to be used as ‘trap crops’ for controlling O. aegyptiaca Persoon. In the experiments, the ability of three popular lily cultivars (Lilium Oriental hybrids ‘Sorbonne’, Lilium LA (Longiflorum hybrids x Asiatic hybrids) hybrids ‘Ceb Dazzle’, and Lilium Longiflorum hybrids (L. formosanum x L. longiflorum) ‘L. formolongo’) to induce O. aegyptiaca Persoon. seed germination was assessed. Parts of the three lily cultivars, including the rhizosphere soil and underground and above-ground organs, all induced “suicidal germination” of parasitic O. aegyptiaca Persoon. seed at four growth stages. Specifically, Sorbonne and Ceb Dazzle behaved with similar allelopathy, and the bulb, scale leaf and aerial stem exhibited stronger allelopathic effects on O. aegyptiaca Pers. germination compared to other organs. Aqueous L. formolongo leaf extracts may contain more stable, effective stimulants given that they induced the highest germination rate at 76.7% even though the extracts were serially diluted. We speculate that these organs may be advantageous in further isolating and purifying economical active substances that can be substitutes for GR24. These results indicate that lilies have the potential to be used as a trap crops or can be processed into green herbicide formulations that can be applied in agriculture production to rapidly deplete the seed bank of O. aegyptiaca Persoon. parasitic weeds in soil. 相似文献
992.
Ying Si Soojin Kim Xiangqin Cui Lei Zheng Shin J. Oh Tina Anderson Mohammad AlSharabati Mohamed Kazamel Laura Volpicelli-Daley Marcas M. Bamman Shaohua Yu Peter H. King 《PloS one》2015,10(9)
We recently identified Smads1, 5 and 8 as muscle biomarkers in human ALS. In the ALS mouse, these markers are elevated and track disease progression. Smads are signal transducers and become activated upon receptor engagement of ligands from the TGF-β superfamily. Here, we sought to characterize ligands linked to activation of Smads in ALS muscle and their role as biomarkers of disease progression. RNA sequencing data of ALS muscle samples were mined for TGF-β superfamily ligands. Candidate targets were validated by qRT-PCR in a large cohort of human ALS muscle biopsy samples and in the G93A SOD1 mouse. Protein expression was evaluated by Western blot, ELISA and immunohistochemistry. C2C12 muscle cells were used to assess Smad activation and induction. TGF-β1, 2 and 3 mRNAs were increased in ALS muscle samples compared to controls and correlated with muscle strength and Smads1, 2, 5 and 8. In the G93A SOD1 mouse, the temporal pattern of TGF-β expression paralleled the Smads and increased with disease progression. TGF-β1 immunoreactivity was detected in mononuclear cells surrounding muscle fibers in ALS samples. In muscle cells, TGF-β ligands were capable of activating Smads. In conclusion, TGF-β1, 2 and 3 are novel biomarkers of ALS in skeletal muscle. Their correlation with weakness in human ALS and their progressive increase with advancing disease in the ALS mouse suggest that they, as with the Smads, can track disease progression. These ligands are capable of upregulating and activating Smads and thus may contribute to the Smad signaling pathway in ALS muscle. 相似文献
993.
Synthesis of Triazole Schiff’s Base Derivatives and Their Inhibitory Kinetics on Tyrosinase Activity
Feng Yu Yu-Long Jia Hui-Fang Wang Jing Zheng Yi Cui Xin-Yu Fang Lin-Min Zhang Qing-Xi Chen 《PloS one》2015,10(9)
In the present study, new Schiff’s base derivatives: (Z)-4-amino-5-(2-(3- fluorobenzylidene)hydrazinyl)-4H-1,2,4-triazole-3-thiol (Y1), (Z)-3-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y2), (Z)-2-((2-(4-amino-5- mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y3) and 3-((Z)-(2-(4- (((E)-3-hydroxybenzylidene)amino)-5-mercapto-4H-1,2,4-triazol-3-yl)hydrazono)methyl)phenol (Y4) were synthesized and their structures were characterized by LC-MS, IR and 1H NMR. The inhibitory effects of these compounds on tyrosinase activites were evaluated. Compounds Y1, Y2 and Y3 showed potent inhibitory effects with respective IC50 value of 12.5, 7.0 and 1.5 μM on the diphenolase activities. Moreover, the inhibition mechanisms were determined to be reversible and mixed types. Interactions of the compounds with tyrosinase were further analyzed by fluorescence quenching, copper interaction, and molecular simulation assays. The results together with the anti-tyrosinase activities data indicated that substitution on the second position of benzene ring showed superior ant-ityrosinase activities than that on third position, and that hydroxyl substitutes were better than fluorine substitutes. In addition, two benzene rings connecting to the triazole ring would produce larger steric hindrance, and affect the bonding between tyrosinase and inhibitors to decrease the inhibitory effects. The anti-tyrosinase effects of these compounds were in contrast to their antioxidant activities. In summary, this research will contribute to the development and design of antityrosinase agents. 相似文献
994.
995.
Tong tong Ge Xiao Xiao Yao Feng Lian Zhao Xiao han Zou Wei Yang Ran Ji Cui Bing jin Li 《Journal of cellular and molecular medicine》2020,24(8):4524-4532
Leptin is well acknowledged as an anorexigenic hormone that plays an important role in feeding control. Hypothalamic GABA system plays a significant role in leptin regulation on feeding and metabolism control. However, the pharmacological relationship of leptin and GABA receptor is still obscure. Therefore, we investigated the effect of leptin or combined with baclofen on the food intake in fasted mice. We detected the changes in hypothalamic c‐Fos expression, hypothalamic TH, POMC and GAD67 expression, plasma insulin, POMC and GABA levels to demonstrate the mechanisms. We found that leptin inhibit fasting‐induced increased food intake and activated hypothalamic neurons. The inhibitory effect on food intake induced by leptin in fasted mice can be reversed by pretreatment with baclofen. Baclofen reversed leptin's inhibition on c‐Fos expression of PAMM in fasted mice. Therefore, these results indicate that leptin might inhibit fasting‐triggered activation of PVN neurons via presynaptic GABA synaptic functions which might be partially blocked by pharmacological activating GABA‐B. Our findings identify the role of leptin in the regulation of food intake. 相似文献
996.
997.
细菌视紫红质(bacteriorhodopsin,bR)是一种光驱受体蛋白,每个活性单元由3个单体组成,每个单体由一分子视蛋白和一分子的视黄醛发色团共价结合而成,其功能为从胞内向胞外定向传输质子,利用形成的质子浓度梯度将光能转化为化学能.光照后视黄醛发色团构型发生all-trans向13-cis转变,蛋白的构象也随之发生了一系列具有稳定中间态的变化并驱动质子的定向传递.为探讨bR视黄醛键合区保守性氨基酸色氨酸86 (Tryptop-han86,w86)对其光循环中间态和质子泵功能的影响,本研究采用定点突变技术将W86突变为侧链大小不同的F86和A86,通过原位紫外-可见光吸收光谱、闪光光解光谱、pH滴定、固体核磁共振等技术手段,探究W86F和W86A突变对bR光循环及质子泵功能影响差异性的分子机制.结果 表明,W86F和W86A突变均造成了bR暗适应状态下视黄醛顺反异构平衡向顺式构型占优的方向移动,且W86F突变可造成反式构型的完全消失.此外,无论是W86F还是W86A突变都造成了蛋白光循环中间态的减弱且衰减延长,以及质子泵功能减弱,但影响机制各有所不同,这可能与这两个突变对视黄醛多烯链上电子云的分布以及周围残基造成的扰动程度不同有关. 相似文献
998.
Muhammad Nasir Chen-chen Zhao Jun-yu Luo Xiang-zhen Zhu Xue-ke Gao Mazher F. Iqbal Ji-chao Ji Shuai Zhang Jin-jie Cui 《Journal of Asia》2021,24(1):297-307
The genetically modified cotton holding Bt proteins, is noxious to bollworms larvae but very little is known about its impact on population of non-target spiders within the field. Studies conducted with the aim to identify spiders along with their abundance, prevalence pattern, preying habit on insect pests in Bt cotton (L280, Cry2Ab4) and commonness of symbiotic bacteria in these spiders. Spiders collections were made via vial tapping/jarring, from May to end of October (2018). In total, 13,342 spiders were recorded during the entire cropping season. Least relative abundance was in May (0.28%), highest in August (30.39%) while ahead decline was observed, reached to 12% in October. The 27 species were verified, least richness was in May (3 species), high in August (19 species), later in the end, reduced to 7 species. High abundance was of Hylyphantes graminicola (68.56%) and Neoscona theisi (19.98%). Existence of H. graminicola and Pardosa astrigera observed during the whole cropping season. Presence of seven guilds among spiders had a diverse nature of hunting insect pests and on number of species existed in the crop, maximum was from direct hunting habit. Composition and community structure of microbiota varied as of spider species. Proteobacteria was the most abundant bacterial phylum and topmost genus was Wolbachia in observed spiders. Five groups of bacteria distinguished across 4 clusters of spiders depending on core community of symbiotic bacterial genera. This effort is an initial step to get knowhow about spiders in Bt cotton, which will facilitate future research studies concerning spiders. 相似文献
999.
Mengmeng Zhuang Yuequ Deng Wenwen Zhang Bo Zhu Hao Yan Jiaqi Lou Pan Zhang Qingwei Cui Hao Tang Han Sun Yong Sun 《Cell death & disease》2021,12(6)
Intestinal mucosal injuries are directly or indirectly related to many common acute and chronic diseases. Long non-coding RNAs (lncRNAs) are expressed in many diseases, including intestinal mucosal injury. However, the relationship between lncRNAs and intestinal mucosal injury has not been determined. Here, we investigated the functions and mechanisms of action of lncRNA Bmp1 on damaged intestinal mucosa. We found that Bmp1 was increased in damaged intestinal mucosal tissue and Bmp1 overexpression was able to alleviate intestinal mucosal injury. Bmp1 overexpression was found to influence cell proliferation, colony formation, and migration in IEC-6 or HIEC-6 cells. Moreover, miR-128-3p was downregulated after Bmp1 overexpression, and upregulation of miR-128-3p reversed the effects of Bmp1 overexpression in IEC-6 cells. Phf6 was observed to be a target of miR-128-3p. Furthermore, PHF6 overexpression affected IEC-6 cells by activating PI3K/AKT signaling which was mediated by the miR-128-3p/PHF6 axis. In conclusion, Bmp1 was found to promote the expression of PHF6 through the sponge miR-128-3p, activating the PI3K/AKT signaling pathway to promote cell migration and proliferation.Subject terms: Cell growth, Cell migration 相似文献
1000.