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Vibrio harveyi is a normal flora in natural marine habitats and a significant opportunistic pathogen in marine animals. This bacterium can cause a series of lesions after infecting marine animals, in which muscle necrosis and ulcers are the most common symptoms. This study explored the adaptation mechanisms of V. harveyi from the seawater environment to host fish muscle environment. The comprehensive transcriptome analysis revealed dramatic changes in the transcriptome of V. harveyi during its adaptation to the host fish muscle environment. Based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, flagellar assembly, oxidative phosphorylation, bacterial chemotaxis, and two-component systems play crucial roles in V. harveyi's adaptation to host fish muscle. A comparison of biological phenotypes revealed that V. harveyi displayed a significant increase in flagellar length, swimming, twitching, chemotaxis, adhesion, and biofilm formation after induction by host fish muscle, and its dominant amino acids, especially bacterial chemotaxis induced by host muscle, Ala and Arg. It could be speculated that the enhancement of bacterial chemotaxis induced by amino acids plays a key role in the adaptation of V. harveyi from seawater to the muscle of the host fish. [ABSTRACT FROM AUTHOR]

Aeromonas hydrophila infections are common in aquaculture. Our previous studies found that the A. hydrophila B11 strain can survive in fish macrophages for at least 24 h and the two‐component system EnvZ/OmpR may be involved in intracellular survival. To reveal the role and mechanism of the two‐component system EnvZ/OmpR in intracellular survival of A. hydrophila, the genes of envZ/ompR were silenced by shRNAi. The results showed that the survival rates of the envZ‐RNAi and ompR‐RNAi strains were only 2.05% and 3.75%, respectively, which were decreased by 91% and 83.6% compared with that of the wild‐type strain. The escape ability of envZ‐RNAi and ompR‐RNAi was also decreased by 51.4% and 19.7%, respectively. The comparative transcriptome analysis revealed that the functional genes directly related to bacterial intracellular survival mainly included the genes related to anti‐stress capacity, and the genes related to Zn2+ and Mg2+ transport. Further research confirmed that two‐component system EnvZ/OmpR can regulate the expression of the important molecular chaperones, such as groEL, htpG, dnaK, clpB and grpE. The expression of these molecular chaperones in wild‐type strain was up‐regulated with the increase in H2O2 concentrations, while the expression of these molecular chaperones in silent strains did not change significantly. Cells that phagocytosed wild‐type strain had higher ROS content than cells that phagocytosed silent strains. Two‐component system EnvZ/OmpR could also regulate zinc transporter (znuA, znuB, znuC) and zinc efflux protein (zntA) to maintain zinc homeostasis in cells, thus affecting the ability of bacteria to survive in phagocytes. Moreover, two‐component system EnvZ/OmpR could affect the growth and intracellular survival of A. hydrophila by regulating the expression of MgtA, MgtC and MgtE and participating in bacterial Mg2+ homeostasis in fish macrophages. [ABSTRACT FROM AUTHOR]

The surface properties of the adsorbents and the acidic environment have an influence effect on Pb adsorption. In order to further improve the adsorption performance of biochar, we herein reported an effective method to synthesize high-adsorbed biochar by co-doping with nitrogen and phosphorus. After atom doping, the N/P co-doped biochar (NP-BC) showed the enhanced adsorption capacity for lead ion (Pb2+). The adsorption kinetics, isotherm, pH value, and influencing factors were studied. The results show that the synthesized NP-BC has high Pb2+ adsorption capacity in aqueous solution, and can be maintained with various environmental interference factors including pH, natural organic matter, and other metal ions. High adsorption performance shows that the material may be well used to remove Pb2+ in various water bodies. Various characterization experiments prove that surface properties contribute to Pb2+ adsorption, and the high performance of NP-BC is mainly due to the surface complexation between functional groups and Pb2+. This work demonstrates that the surface functional groups of biochar are critical to the development of high-performance heavy metal adsorbents. [ABSTRACT FROM AUTHOR]

A novel thrust control method based on inverse control is proposed to improve engine response ability. The On Line Sliding Window Deep Neural Network (OL SW DNN) is proposed and adopted as inverse mapping model modeling method of inverse control. The OL SW DNN has deeper layer structure, which makes the inverse mapping model have stronger fitting capacity for nonlinear object than traditional NN. Moreover, due to adopt on-line learning modeling method, the proposed adaptive control method can obtain desired thrust whether engine degrades or not. The comparison simulations of the traditional control method based on PID and the proposed control method are carried out. Compared with the traditional control method, the proposed control method can obtain desired thrust when the engine degradation occurs, but also has fast response ability (the acceleration times for engine thrust increase to 95 % thrust of acceleration object decreases by 1.35 seconds). [ABSTRACT FROM AUTHOR]

Purpose: The aim was to compare the efficacy and toxicity of gemcitabine plus docetaxel (GD) with platinum-based regimens in patients with untreated advanced non-small cell lung cancer (NSCLC). Methods: We searched PubMed, Embase and the Cochrane Central Register of Controlled Trials databases for relevant trials. Reference lists of original articles and review articles were also examined. Abstracts presented at the ASCO and ESMO meetings were also searched. Studies were evaluated for eligibility and quality, and then, the data were extracted and analyzed. Statistical analyses were conducted by using RevMan 5.1. The primary end point was overall survival (OS). Secondary end points included 1-year survival, time to progression (TTP), overall response rate (ORR) and grade 3-4 toxicity. Results: Nine randomized controlled trials were identified ultimately. The meta-analysis demonstrated that the survival between GD and platinum-based regimens was comparable according to the pooled HR for overall survival (1.04, 95% CI = 0.96-1.12, p = 0.39) and RR for one-year survival (0.94, 95% CI = 0.84-1.06, p = 0.33). Platinum-based regimens had an advantage in TTP (HR = 1.12, 95% CI = 1.02-1.24, p = 0.02) and ORR (RR = 0.86, 95% CI = 0.74-0.99, p = 0.03). However, GD induced less grade 3-4 nausea/vomiting, anemia, neutropenia and febrile neutropenia (RR = 0.36, 95% CI = 0.15-0.86, p = 0.02; RR = 0.35, 95% CI = 0.23-0.53, p = 0.00; RR = 0.68, 95% CI = 0.52-0.88, p = 0.003; RR = 0.53, 95% CI = 0.34-0.82, p = 0.004, respectively). Grade 3-4 diarrhea, sensory neuropathy, fatigue and thrombocytopenia were comparable between the two groups. Conclusions: GD acquired similar survival with platinum-based regimens in first-line treatment of advanced NSCLC. Platinum-based regimens had an advantage in TTP and ORR with more grade 3-4 nausea/vomiting, anemia, neutropenia and febrile neutropenia compared with GD. [ABSTRACT FROM AUTHOR]