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81.
The hemolymph protein HP19 of the rice moth, Corcyra cephalonica, mediates the 20-hydroxyecdysone (20E)-dependent acid phosphatase (ACP) activity at a nongenomic level. Affinity-purified polyclonal antibody against HP19 (alphaHP19-IgG) was used in the present study to understand the role of HP19 during the postembryonic development of Corcyra. In the in vitro studies, HP19 action was blocked either by immuno-precipitation using alphaHP19-IgG, prior to its addition to the fat body culture or by the addition of the antibody directly to the culture, along with 20E and hemolymph containing HP19. The alphaHP19-IgG blocked the HP19-mediated 20E-dependent ACP activation. In the in vivo studies, the alphaHP19-IgG was injected into the fully developed last (final/Vth) instar larvae of Corcyra, to complex the HP19 in vivo, in order to block the action of HP19. The injection of alphaHP19-IgG resulted in defective development of larvae, which grew either into non-viable larvae or larval-pupal/pupal-adult intermediates relative to the effect of pre-immune IgG injected controls. The present study shows that HP19 plays an important role in controlling the metamorphosis of Corcyra by regulating the 20E-dependent ACP activity. Coupled with the earlier findings, the ecdysteroid hormone regulates this action at a nongenomic level.  相似文献   
82.
Most familial behavioral phenotypes result from the complex interaction of multiple genes. Studies of such phenotypes involving human subjects are often inconclusive owing to complexity of causation and experimental limitations. Studies of animal models argue for the use of established genetic strains as a powerful tool for genetic dissection of behavioral disorders and have led to the identification of rare genes and genetic mechanisms implicated in such phenotypes. We have used microarrays to study global gene expression in adult brains of four genetic strains of mice (C57BL/6J, DBA/2J, A/J, and BALB/c). Our results demonstrate that different strains show expression differences for a number of genes in the brain, and that closely related strains have similar patterns of gene expression as compared with distantly related strains. In addition, among the 24 000 genes and ESTs on the microarray, 77 showed at least a 1.5-fold increase in the brains of C57BL/6J mice as compared with those of DBA/2J mice. These genes fall into such functional categories as gene regulation, metabolism, cell signaling, neurotransmitter transport, and DNA/RNA binding. The importance of these findings as a novel genetic resource and their use and application in the genetic analysis of complex behavioral phenotypes, susceptibilities, and responses to drugs and chemicals are discussed.  相似文献   
83.
Reactive oxygen species, such as myeloperoxidase-derived hypochlorite, induce oxidative stress and DNA injury. The subsequent activation of the DNA-damage-poly(ADP-ribose) polymerase (PARP) pathway has been implicated in the pathogenesis of various diseases, including ischemia-reperfusion injury, circulatory shock, diabetic complications, and atherosclerosis. We investigated the effect of PARP inhibition on the impaired endothelium-dependent vasorelaxation induced by hypochlorite. In organ bath experiments for isometric tension, we investigated the endothelium-dependent and endothelium-independent vasorelaxation of isolated rat aortic rings using cumulative concentrations of acetylcholine and sodium nitro-prusside. Endothelial dysfunction was induced by exposing rings to hypochlorite (100-400 microM). In the treatment group, rings were preincubated with the PARP inhibitor INO-1001. DNA strand breaks were assessed by the TUNEL method. Immunohistochemistry was performed for 4-hydroxynonenal (a marker of lipid peroxidation), nitrotyrosine (a marker of nitrosative stress), and poly(ADP-ribose) (an enzymatic product of PARP). Exposure to hypochlorite resulted in a dose-dependent impairment of endothelium-dependent vasorelaxation of aortic rings, which was significantly improved by PARP inhibition, whereas the endothelium-independent vasorelaxation remained unaffected. In the hypochlorite groups we found increased DNA breakage, lipidperoxidation, and enhanced nitrotyrosine formation. The hypochloride-induced activation of PARP was prevented by INO-1001. Our results demonstrate that PARP activation contributes to the pathogenesis of hypochlorite-induced endothelial dysfunction, which can be prevented by PARP inhibitors.  相似文献   
84.
In irrigated agricultural systems, nitrogen (N) and water are the vital resources for sustainability of the crop production in the modern era of climate change. The current study aimed to assess the impact of water and N management on the productivity of irrigated rice cultivars. In the context, a field observation was done at the research farm of Bangladesh Agricultural University, Mymensingh, during dry seasons in consecutive two years (2018–2019 and 2019–2020). The experiments were set up following split-plot design assigning water management in the main plots, nitrogen management in the sub-plots, and the cultivars were approved in the split-split plot with three replications. After two years observation, it was revealed that rice cultivar Binadhan-8 gave the maximum value of leaf area index, number effective tillers hill-1 and grains panicle-1 which lead to the higher grain yield (GY). Substantial relationships were observed among the concentration of N, growth, total dry matter (TDM) and N content, N uptake, N utilization effectiveness, and GY. However, with little exception, the Combined effect of water and N, cultivars and water management were varied significantly for all parameters. Finally, the results of the current study concluded that application of irrigation at 8 days after the disappearance of ponded water and source of 105 kg N ha-1 from PU + Poultry manure are the best management approach for the excellent performance of rice cultivar Binadhan-8.  相似文献   
85.
Molecular Biology Reports - The SHANK3 gene encodes a master synaptic scaffolding protein at the excitatory synapse’s postsynaptic density, which is predominantly responsible for constructing...  相似文献   
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Matrix metalloproteinase-8 (MMP8) has been shown to influence various cellular functions. As monocytes and macrophages (Mφ) express MMP8, we investigated if MMP8 played a role in macrophage differentiation and polarization. MMP8 expression was significantly increased during monocyte differentiation into Mφ. Monocyte-derived Mφ from MMP8-deficient mice expressed higher levels of M1-Mφ markers but lower levels of M2-Mφ markers than monocyte-derived Mφ from wild-type mice. Although Mφ from either MMP8-deficient or wild-type mice were inducible by interferon-γ into M1-Mφ, only wild-type Mφ but not MMP8-deficient Mφ could be induced into M2-Mφ by interleukin-4. However, MMP8-deficient Mφ exposed to conditioned culture media of wild-type Mφ developed a M2-Mφ phenotype. Compared with conditioned culture media of wild-type Mφ, conditioned culture media of MMP8-deficient Mφ contained a lower concentration of active transforming growth factor-β (TGF-β), an M2-Mφ inducer. Moreover, evidence also showed that the degradation of the TGF-β sequester, fibromodulin, was modulated by MMP8. The data indicate a previously unknown role of MMP8 in M2-Mφ polarization by cleaving fibromodulin and therefore increasing the bioavailability of the M2-Mφ inducer TGF-β.  相似文献   
90.
Cyclooxygenase-2 (COX-2) catalyzed synthesis of prostaglandin E2 and it associates with tumor growth, infiltration, and metastasis in preclinical experiments. Known inhibitors against COX-2 exhibit toxicity. Therefore, it is of interest to screen natural compounds like flavanoids against COX-2. Molecular docking using 12 known flavanoids against COX-2 by FlexX and of ArgusLab were performed. All compounds showed a favourable binding energy of >-10 KJ/mol in FlexX and > -8 kcal/mol in ArgusLab. However, this data requires in vitro and in vivo verification for further consideration.  相似文献   
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