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A novel class of colchicine-SAHA hybrids were designed and synthesised based on the synergistic antitumor effect of tubulin inhibitors and histone deacetylases (HDAC) inhibitors. To the best of our knowledge, this is the first design of molecules that are dual inhibitors of tubulin and HDAC. Biological evaluations of these compounds included the inhibitory activity of HDAC, in vitro cell cycle analysis in BEL-7402 cells as well as cytotoxicity in five cancer cell lines.  相似文献   
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The enhanced electricity generation in a biocathode bio-electrochemical system (BES) with Microcystis aeruginosa IPP as the cathodic microorganism under illumination is investigated. The results show that this cyanobacterium is able to act as a potential cathodic microorganism under illumination. In addition, M. aeruginosa IPP is found to produce reactive oxygen species (ROS) in its growth in the BES. ROS, as more competitive electron acceptors than oxygen, are utilized prior to oxygen. The BES current is substantially reduced when the ROS production is inhibited by mannitol, indicating that the ROS secreted by the cyanobacterium play an important role in the electricity generation of such a biocathode BES. This work demonstrates that the ROS released by cyanobacteria benefit for an enhanced electricity generation of BES.  相似文献   
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The expression and impact of maternal effects may vary greatly between populations and environments. However, little is known about large‐scale geographical patterns of variation in maternal deposition to eggs. In birds, as in other oviparous animals, the outermost maternal component of an egg is the shell, which protects the embryo, provides essential mineral resources and allows its interaction with the environment in the form of gas exchange. In this study, we explored variation of eggshell traits (mass, thickness, pore density and pigmentation) across 15 pied flycatcher populations at a large geographic scale. We found significant between‐population variation in all eggshell traits, except in pore density, suggesting spatial variation in their adaptive benefits or in the females’ physiological limitations during egg laying. Between‐ population variation in shell structure was not due to geographic location (latitude and longitude) or habitat type. However, eggshells were thicker in populations that experienced higher ambient temperature during egg laying. This could be a result of maternal resource allocation to the shell being constrained under low temperatures or of an adaptation to reduce egg water loss under high temperatures. We also found that eggshell colour intensity was positively associated with biliverdin pigment concentration, shell thickness and pore density. To conclude, our findings reveal large‐ scale between‐population variation of eggshell traits, although we found little environmental dependency in their expression. Our findings call for further studies that explore other environmental factors (e.g. calcium availability and pollution levels) and social factors like sexual selection intensity that may account for differences in shell structure between populations.  相似文献   
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ObjectivesTo assess the association between the variant of Cytochrome P450 2A6 whole gene deletion (CYP2A6*4) polymorphism and risk of lung cancer.MethodsTwo investigators independently searched the PubMed, Elsevier, EMBASE, Web of Science, Wiley Online Library and Chinese National Knowledge Infrastructure (CNKI). Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) for CYP2A6*4 and lung cancer were calculated in a fixed-effects model (the Mantel-Haenszel method) and a random-effects model (the DerSimonian and Laird method) when appropriate.ResultsThis meta-analysis included seven eligible studies, which included 2524 lung cancer cases and 2258 controls (cancer–free). Overall, CYP2A6*4 was associated with the risk of lung cancer (allele*4 vs. allele non-*4, pooled OR  = 0.826, 95% CI  = 0.725−0.941, P-value  = 0.004). When stratifying for population, significant association was observed in Asian (additive model, pooled OR  = 0.794, 95% CI  = 0.694−0.909, P-value  = 0.001; dominant model, pooled OR  = 0.827, 95% CI  = 0.709−0.965, P-value  = 0.016; recessive model (pooled OR  = 0.444, 95% CI  = 0.293−0.675, P-value <0.0001). In the overall analysis, a comparably significant decrease in the frequency of *4/*4 genotype was detected between cases and controls in Asian while no *4/*4 genotype was detected in Caucasian in collected data.ConclusionThis meta-analysis suggests that the CYP2A6*4 polymorphism is associated with susceptibility of lung cancer in Asian. The whole gene deletion of CYP2A6 may decrease the risk of lung cancer in Asian samples.  相似文献   
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Metastasis remains to be one of the most prevalent causes leading to poor long-term survival of colorectal cancer (CRC) patients. The clinical significances of tumor metastatic suppressor, N-myc downregulated gene 1 (NDRG1), have been inconsistently reported in a variety of cancerous diseases. In this study with 240 CRC clinical specimens, we showed that NDRG1 expression was significantly decreased in most of CRC tissues compared to the paired non-tumor counterparts. Statistical analysis revealed a significant inverse correlation of NDRG1 expression with tumor stage, differentiation status and metastasis. Compared with NDRG1-negative group, NDRG1-positve group had better disease-free/overall survival (p = 0.000) over 5 years’ follow-up. Furthermore, NDRG1 was considered to be an independent prognostic factor for overall survival (p = 0.001) and recurrence (p = 0.003). Our study concludes that NDRG1 is a novel favorable predictor for the prognosis in CRC patients.  相似文献   
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