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211.
Two flavonoids, tectoridin (TD) isolated from rhizomes of Iris tectorum and hydrolyzed aglycone tectorigenin (TG) were prepared and characterized to compare their different interaction ability with human serum albumin (HSA). Based on the results, the affinity of TG–HSA was stronger than that of TD–HAS, and TG combined more closely with HSA than did TD. HSA fluorescence was quenched by TD/TG. The interactions between TD/TG and HSA involved static quenching. The thermodynamic parameters indicated that both binding processes were spontaneous; hydrogen binding and van der Waals force were the main forces between TD and HSA, whereas a hydrophobic interaction was the main binding force between TG and HSA. Synchronous and 3D fluorescence spectra showed that the binding of TD/TG to HSA induced conformational changes. Moreover, a docking study confirmed the experimental results. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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213.
An efficient serum marker for hepatocellular carcinoma (HCC) is currently lacking and requires intensive exploration. We aimed to evaluate the performance of des-gamma-carboxy prothrombin (DCP) for identifying hepatitis B virus-related HCC in a large, multicentre study in China. A total of 1034 subjects in three cohorts (A, B, and C) including HCC and various non-HCC controls were enrolled from 4 academic medical centers in China from January 2011 to February 2014. Blind parallel detections were conducted for DCP and AFP. The area under the receiver operating characteristic curve (AUC) was used to evaluate the diagnostic efficacies. In cohort A, which comprised 521 subjects, including patients with HCC, liver metastasis, liver cirrhosis (LC), and liver hemangiomas as well as healthy controls (HCs), the accuracy of DCP for distinguishing HCC from various controls was 6.2–9.7% higher than that of AFP. In cohort B, which comprised 447 subjects, including patients with HCC, LC, and chronic hepatitis B as well as HC, the accuracy of DCP was further elevated (12.3–20.67% higher than that of AFP). The superiority of DCP to AFP was more profound in the surveillance of early HCC [AUC 0.837 (95% CI: 0.771–0.903) vs. 0.650 (0.555–0.745)] and AFP-negative HCC [AUC: 0.856 (0.798–0.914)] and in discriminating HCC from LC (accuracy: 92.9% vs.64.71%). Higher DCP levels were associated with worse clinical behaviors and shorter disease-free survival. DCP not only is complementary to AFP in identifying AFP-negative HCC and in excluding AFP-positive non-HCC (liver cirrhosis), but also demonstrates improved performance in HCC surveillance, early diagnosis, treatment response and recurrence monitoring in the HBV-related population.  相似文献   
214.
Lung carcinoma is the most common type of malignant tumors globally, and its molecular mechanisms remained unclear. With the aim to investigate the effects of microRNA (miR)-377-5p on the cell development, invasion, metastasis, and cycle of lung carcinoma, this study was performed. We evaluated miR-377-5p expression levels in lung cancer tissues and cell models. Cell viability, proliferation, migration, invasion abilities, and cell cycle distribution were measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, crystal violet, transwell, and flow cytometry assay. Furthermore, expression levels of protein kinase B α subunit (AKT1) and proteins related to cell cycle and epithelial-mesenchymal transition (EMT) were assessed using Western blot analysis and quantitative real-time polymerase chain reaction. These results suggested that miR-377-5p was downregulated in vivo and in cell models, and miR-377-5p overexpression inhibited cell viability, proliferation, migration, invasion, and induced cell-cycle arrest. In addition, as a target of miR-377-5p, AKT1 alleviated the decreases of cell viability, proliferation, migration, invasion, the S-phase cells, the expression of cyclin D1, fibronectin, and vimentin, as well as the increases of the G0/G1-phase cells, the expression of Foxo1, p27 kip1, p21 Cip1 and E-cadherin when miR-377-5p overexpressed. In conclusion, miR-377-5p inhibited cell development and regulated cell cycle distribution and EMT by targeting AKT1, which provided a theoretical basis for further study of lung carcinoma therapeutics.  相似文献   
215.
Lung cancer is the leading cause of cancer-related deaths worldwide. Epithelial-mesenchymal transition (EMT) is a major event that drives cancer progression. Here we aim to investigate the role of microRNA, miR-145, in regulating EMT of the highly invasive non–small cell lung cancer (NSCLC). Quantitative real-time polymerase chain reaction analysis indicated that miR-145 was downregulated in cancer tissue compared with that in adjacent normal tissue. NSCLC cell lines, namely H1299, PC7, and SPCA-1, also demonstrated miR-145 downregulation, which is correlated well with their invasive ability, assessed by the Matrigel invasion assay. miR-145 overexpression resulted in downregulation of N-cadherin, and downregulation of vimentin and E-cadherin, suggesting a decreased EMT activity. TargetScan analysis predicted that a binding site exists between miR-145 and an oncogene, ZEB2, which was verified using the dual-luciferase assay. Alteration of miR-145 expression also induced inverse effects on ZEB2 expression, and a negative correlation exists between ZEB2 and miR-145 in human tissues. ZEB2 and miR-145 also exerted antagonizing effects on the invasion of NSCLC cells. Therefore, miR-145 is an important molecule in NSCLC that regulates cancer EMT through targeting ZEB2.  相似文献   
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217.
Redox flow batteries have considerable advantages of system scalability and operation flexibility over other battery technologies, which makes them promising for large‐scale energy storage application. However, they suffer from low energy density and consequently relatively high cost for a nominal energy output. Redox targeting–based flow batteries are employed by incorporating solid energy storage materials in the tank and present energy density far beyond the solubility limit of the electrolytes. The success of this concept relies on paring suitable redox mediators with solid materials for facilitated reaction kinetics and lean electrolyte composition. Here, a redox targeting‐based flow battery system using the NASICON‐type Na3V2(PO4)3 as a capacity booster for both the catholyte and anolyte is reported. With 10‐methylphenothiazine as the cathodic redox mediator and 9‐fluorenone as anodic redox mediator, an all‐organic single molecule redox targeting–based flow battery is developed. The anodic and cathodic capacity are 3 and 17 times higher than the solubility limit of respective electrolyte, with which a full cell can achieve an energy density up to 88 Wh L?1. The reaction mechanism is scrutinized by operando and in‐situ X‐ray and UV–vis absorption spectroscopy. The reaction kinetics are analysed in terms of Butler–Volmer formalism.  相似文献   
218.
Increasing drought and extreme rainfall are major threats to maize production in the United States. However, compared to drought impact, the impact of excessive rainfall on crop yield remains unresolved. Here, we present observational evidence from crop yield and insurance data that excessive rainfall can reduce maize yield up to ?34% (?17 ± 3% on average) in the United States relative to the expected yield from the long‐term trend, comparable to the up to ?37% loss by extreme drought (?32 ± 2% on average) from 1981 to 2016. Drought consistently decreases maize yield due to water deficiency and concurrent heat, with greater yield loss for rainfed maize in wetter areas. Excessive rainfall can have either negative or positive impact on crop yield, and its sign varies regionally. Excessive rainfall decreases maize yield significantly in cooler areas in conjunction with poorly drained soils, and such yield loss gets exacerbated under the condition of high preseason soil water storage. Current process‐based crop models cannot capture the yield loss from excessive rainfall and overestimate yield under wet conditions. Our results highlight the need for improved understanding and modeling of the excessive rainfall impact on crop yield.  相似文献   
219.
The current study aimed to investigate the mechanism by which miR-454 influences the progression of heart failure (HF) in relation to the neural precursor cell expressed, developmentally downregulated 4-2 (NEDD4-2)/tropomyosin receptor kinase A (TrkA)/cyclic adenosine 3',5'-monophosphate (cAMP) axis. Sprague-Dawley rats were used to establish a HF animal model via ligation of the left anterior descending branch of the coronary artery. The cardiomyocyte H9c2 cells were treated with H2O2 to stimulate oxidative stress injury in vitro. RT-qPCR and Western blot assay were subsequently performed to determine the expression patterns of miR-454, NEDD4-2, TrkA, apoptosis-related proteins and cAMP pathway markers. Dual-luciferase reporter gene assay coupled with co-immunoprecipitation was performed to elucidate the relationship between miR-454, NEDD4-2 and TrkA. Gain- or loss-of-function experiments as well as rescue experiments were conducted via transient transfection (in vitro) and adenovirus infection (in vivo) to examine their respective functions on H9c2 cell apoptosis and myocardial damage. Our results suggested that miR-454 was aberrantly downregulated in the context of HF, while evidence was obtained suggesting that it targeted NEDD4-2 to downregulate NEDD4-2 in cardiomyocytes. miR-454 exerted anti-apoptotic and protective effects on cardiomyocytes through inhibition of NEDD4-2, while NEDD4-2 stimulated ubiquitination and degradation of TrkA protein. Furthermore, miR-454 activated the cAMP pathway via the NEDD4-2/TrkA axis, which ultimately suppressed cardiomyocyte apoptosis and attenuated myocardial damage. Taken together, the key findings of the current study highlight the cardioprotective role of miR-454, which is achieved through activation of the cAMP pathway by impairing NEDD4-2-induced TrkA ubiquitination.  相似文献   
220.
The nucleus of a blastula cell from Tilapia (Oreochromis nilotica, family Cichlidae, order Perciformes) was transplanted into an enucleated egg of Loach (Paramisgurnus dabryanus, family Cobitidae, order Cypriniformes). From among 3747 nucleo-cytoplasmic hybrid (NCH) eggs two NCH larval fish (0.05%) were obtained; one died on the 6th day and the other died on the 12th day after the operation. Morphological examinations showed that both NCH larval fish had developed normally with an opened mouth except they could not take food after complete utilization of their egg yolk on the 5th day of development. The possible mechanisms for obtaining such inter-order NCH larval fish are discussed. This is the first report indicating that inter-order NCH larval fish can be obtained in spite of their evolutionary divergence.  相似文献   
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