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ABSTRACT Transcriptome analysis is important for interpreting the functional elements of the genome and revealing the molecular constituents of cells and tissues. Herein, differentially transcribed genes were identified by deep sequencing after zebrafish ( Danio rerio) were exposed to β-diketone antibiotics (DKAs); 23,129 and 23,550 mapped genes were detected in control and treatment groups, a total of 3238 genes were differentially expressed between control and treatment groups. Of these genes, 328 genes (213 up- and 115 down-regulation) had significant differential expression ( p < 0.05) and an expression ratio (control/treatment) of >2 or <0.5. Additionally, we performed Gene Ontology (GO) category and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses, and found 266 genes in the treatment group with annotation terms linked to the GO category. A total of 77 differentially expressed transcriptional genes were associated with 132 predicted KEGG metabolic pathways. Serious liver tissue damage was reflected and consistent with the differences in genetic classification and function from the transcriptome analysis. These results enhance our understanding of zebrafish developmental processes under exposure to DKA stress. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1357-1371, 2016. [ABSTRACT FROM AUTHOR]

ABSTRACT Fluoroquinolones (FQs) and tetracyclines (TCs), the two β-diketone antibiotics (DKAs), are two frequently detected pollutants in the environment; however, little data are available on their combined toxicity to zebrafish ( Danio rerio). This study reports that toxicologic effects of combined DKA (FQs-TCs) exposure on zebrafish were comparable with or slightly less than those of TCs alone, showing that TCs played a major toxicologic role in the mixtures. The effects of FQs, TCs, and DKAs on malformation rates of zebrafish were dose dependent, with EC50 values of 481.3, 16.4, and 135.1 mg/L, respectively. According to the combined effects of DKAs on zebrafish hatching, mortality, and malformation rates, the interaction between FQs and TCs was shown to be antagonistic based on three assessment methods: Toxic Unit, Additional Index, and Mixture Toxic Index. The 1.56 mg/L TC and 9.38 mg/L DKA treatments resulted in higher zebrafish basal swimming rate compared with the control group at 120 hours postfertilization (hpf). in both light and light-to-dark photoperiod experiments. Under conditions of no obvious abnormality in cardiac development, the heart beats were decreased significantly because of DKA exposure, such as decreasing by ∼20% at 150 mg/L DKAs. Transmission electron microscopy observation of myocytes from DKA-exposed hearts displayed prominent interruptions and myofibrillar disorganization of the normal parallel alignment of thick and thin filaments, and partial edematous and dissolved membranes of cell nuclear tissues. At 90 mg/L DKAs, the transcriptional levels of the acta1a, myl7, and gle1b genes, related to heart development and skeletal muscle formation, were significantly changed. This is consistent with the swimming behavior and histopathologic results obtained by transmission electron microscopy. In summary, the toxicity of the combined DKAs to zebrafish was comparable with or less than that of TCs alone and had the ability to impair individual behaviors that are of great importance in the assessment of their ecologic fitness. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 736-750, 2016. [ABSTRACT FROM AUTHOR]

The removal efficiency of Cu2+ by Spirulina platensis (strain FACHB-834), in viable and heat-inactivated forms, was investigated in the presence and absence of linear alkylbenzene sulfonate ( LAS). When the initial Cu2+ concentration was in the range of 0.5-1.5 mg · L−1, a slight increase in growth rate of FACHB-834 was observed. In contrast, when Cu2+ or LAS concentrations were at or higher than 2.0 or 6.0 mg · L−1, respectively, the growth of FACHB-834 was inhibited and displayed yellowing and fragmentation of filaments. The presence of LAS improved Cu2+ removal by ~20%, and accelerated attainment of Cu2+ retention equilibrium. For the 2- mg · L−1 Cu2+ treatments, retention equilibrium occurred within 2 d and showed maximum Cu2+ removal of 1.83 mg · L−1. In the presence of LAS, the ratio of extracellular bound Cu2+ to intracellular Cu2+ taken up by the cells was lower (1.05-2.26) than corresponding ratios (2.46-7.85) in the absence of LAS. The percentages of extracellular bound Cu2+ to total Cu2+ removal (both bound and taken up by cells) in the presence of LAS ranged from 51.2% to 69.3%, which was lower than their corresponding percentages (71.1%-88.7%) in the absence of LAS. LAS promoted biologically active transport of the extracellular bound form of Cu2+ into the cell. In contrast, the addition of LAS did not increase the maximum removal efficiency of Cu2+ (61.4% ± 5.6%) by heat-inactivated cells compared to that of living cells (59.6% ± 6.0%). These results provide a theoretical foundation for designing bioremediation strategies using FACHB-834 for use in surface waters contaminated by both heavy metals and LAS. [ABSTRACT FROM AUTHOR]

β-Diketone antibiotics (DKAs) can produce chronic toxicity in aquatic ecosystems due to their pseudo-persistent in the environment. In this study, after long-term DKA exposure to zebrafish (Danio rerio), 47 protein spots had greater than 2-fold differential expression as compared to the control; there were 26 positive proteins with 14 up-regulated and 12 down-regulated. The main functions of the differentially expressed proteins were related to signal transduction mechanisms and the cytoskeleton. Of the 26 target genes, 11 genes were consistent between their transcriptional and translational levels. Low dose DKA exposure (4.69 and 9.38 mg/L) stimulated spontaneous movement in zebrafish. Changes in both creatine kinase activity and creatine concentration showed a similar trend to zebrafish activity. There was no obvious change in SV-BA after DKA exposure, while a reduction of heart rate was concomitant with increasing DKA concentrations. DKAs also induced severe histopathological changes in zebrafish heart tissue, such as dissolution of cristae and vacuolation of mitochondria. These results demonstrated that trace-level DKA exposure affects a variety of cellular and biological processes in zebrafish. [ABSTRACT FROM AUTHOR]

Pancharatnam-Berry (PB) phase, usually utilized for phase manipulation of circularly polarized (CP) waves, has inherent symmetrical response on left-handed polarized (LCP) and right-handed polarized (RCP) for orbital angular momentum (OAM), which severely hinders its application. By modulating both propagation and PB phase allows independent control of LCP and RCP of OAM, but increases the design difficulty. Here, we propose a phase compensation scheme to independent control the CP states of OAM only utilizing PB phase, where arbitrary topological charges and deflection directions of LCP and RCP beams can be realized. Two wideband metasurfaces are designed to independent control the mode, circular polarization and beam directions of OAM at the frequency range of 10-20 GHz. This work significantly motivates the development of polarization division multiplexing in wireless communication system.

Objective: To investigate the effect of unfractionated heparin (UFH) on the expression of heme oxygenase-1 (HO-1) in intestinal mucosa of mice with sepsis., Methods: Thirty-six male C57BL/6J mice were randomly divided into sham group, cecal ligation and puncture (CLP) group and UHF group, n =12 in each group. Model of intestinal injury in sepsis was induced by CLP. In sham group, the mice were exposed without ligation of cecum. In UFH group, the mice were treated intravenously with 8 U of UFH via the tail vein half an hour before the operation and 12 hours after the surgery respectively. Six mice in each group were randomly chosen at 4 hours and 24 hours after operation to collect inferior vena venous blood samples and terminalileum tissues. The serum levels of interleukins (IL-1 β,IL-6),and tumor necrosis factor-α (TNF-α) were determined by enzyme linked immunosorbent assay (ELISA).The serum level of D-lactate was determined by colorimetry.Pathological changes of ileum tissue and Chiu score were observed after hematoxylin eosin (HE) staining. The HO-1 expression was detected immunohistochemically., Results: In sham group, no significant changes in the serum levels of IL-1 β,IL-6,TNF-α and D-lactate were observed. Twenty-four hours after the operation, the structure of intestinal mucosa was basically normal without obvious pathology change and no HO-1 positive cells were found. The serum levels of IL-1 β,IL-6,TNF-α,and D-lactate in CLP group were gradually increased, and they were significantly increased as compared with sham group [IL-1 β (ng/L):40.87±2.88 vs.22.60±2.05 at 4 hours,113.73±3.96 vs.22.07±2.74 at 24 hours;IL-6 (ng/L):63.89±3.26 vs.44.89±3.38 at 4 hours,176.56±5.45 vs.45.76±4.02 at 24 hours; TNF-α (ng/L):194.62± 14.13 vs.152.05±6.22 at 4 hours,599.62± 10.20 vs.155.90± 14.18 at 24 hours; D-lactate (mmol/L):0.24± 0.02 vs.0.19 ± 0.01 at 4 hours,0.33 ± 0.04 vs.0.20 ± 0.02 at 24 hours, all P ＜ 0.05].Twenty-four hours after the operation, edema and inflammation in ileal mucosa, intestinal villi structural damage were observed, the Chiu score was significantly higher than those in the sham group [4.5 (3.0-5.0) vs.0 (0-1.0),P ＜ 0.05],and a small amount of HO-1 positive cells were localized in the intestinal mucosa. Compared with CLP group, the serum levels of IL-1 β,IL-6,TNF-α,and D-lactate of UFH group were significantly decreased [IL-1 β (ng/L):31.53 ± 2.90 vs.40.87 ± 2.88 at 4 hours,61.13 ± 2.80 vs.113.73 ± 3.96 at 24 hours;IL-6 (ng/L):51.16 ± 5.68 vs.63.89 ± 3.26 at 4 hours,81.16 ± 4.54 vs.176.56 ± 5.45 at 24 hours; TNF-α (ng/L):171.76± 5.60 vs.194.62± 14.13 at 4 hours,328.48 ± 10.79 vs.599.62± 10.20 at 24 hours; D-lactate (mmol/L):0.21 ±0.01 vs.0.24±0.02 at 4 hours,0.24±0.02 vs.0.33±0.04 at 24 hours, all P ＜ 0.05]. Twenty-four hours after the operation, intestinal injury was ameliorated, the Chiu score was significantly lower [1.5 (1.0-5.0) vs.4.5 (3.0-5.0),P ＜ 0.05],and HO-1 positive cells in the intestinal mucosa was remarkably increased., Conclusion: UFH can enhance the expression of HO-1 in intestinal mucosa, reduce the release of inflammatory factors, ameliorate the intestinal inflammatory response, and thus play a protective role in intestinal tissue in mice with sepsis.