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A WC/WO2–WO3 nanosheet heterostructure has been fabricated by an in situ electrochemical reconstruction approach, which significantly elevates the HOR performance by 7 times owing to the synergistic catalytic effect between WC and WOx species.

Developing highly efficient, cost effective and durable bifunctional electrocatalyst remains a key challenge for overall water splitting. Herein, a bifunctional catalyst CoP

Earth-abundant tungsten carbide exhibits potential hydrogen evolution reaction (HER) catalytic activity owing to its Pt-like d-band electronic structure, which, unfortunately, suffers from the relatively strong tungsten-hydrogen binding, deteriorating its HER performance. Herein, a catalyst design concept of incorporating late transition metal into early transition metal carbide is proposed for regulating the metal-H bonding strength and largely enhancing the HER performance, which is employed to synthesize CoW bi-metallic carbide Co

Among various earth-abundant and noble metal-free catalysts for oxygen reduction reaction (ORR), Mn and N co-doped carbon (Mn-N-C) is highly desirable and promising, which, however, suffer from the limited amount of active sites largely abating its ORR catalytic performance. Herein we demonstrate an effective strategy to elevate the ORR active site density by designing a helical graphitized carbon tubes to highly disperse the single Mn atomic sites coordinated with nitrogen. The obtained polydopamine-modified helical MnNC-PDA-700 catalyst shows excellent ORR electrocatalytic performance with a half-wave potential of 0.87 V and extra-high Zn-air battery power density of 122.7 mW cm−2, which are comparable to and even higher than those of Pt/C. Such an excellent electrocatalytic performance is attributed to the much enhanced amount of MnN4 active sites created on the helical graphitized carbon tubes owing to high surface area helical structure of the carbon tubes and the strong bonding of polydopamine molecules onto the tubes. The density functional theory (DFT) calculations further confirm that the MnN4 sites are the origin of the superior ORR activity via a 4e− pathway in alkaline media.

Using hydrazine oxidation reaction (HzOR) substituting for oxygen evolution reaction can realize hydrogen production at largely reduced energy consumption. While the HzOR mechanism and the electrochemical utilization rate of hydrazine are still ambiguous. Herein, a bimetallic phosphide heterostructure nanoarrays (Ni-Co-P/NF) fabricated by an interface engineering strategy was used to catalyze both HzOR and hydrogen evolution reaction (HER), and more intensively, probe the HzOR mechanism. The extra-high HzOR performance is attributed to the instantaneous recovery of metal phosphide active site by hydrazine and the extremely low energy barrier with even a new HzOR pathway of N-N bond breakage, which enables the electrolyzer catalyzed by Ni-Co-P/NF to reach 500 mA cm-2 for H2 production at as low as 0.498 V, and offers a high hydrazine electrochemical utilization rate of 93%. The constructed electrolyzer can be powered by the direct hydrazine fuel cell with Ni-Co-P/NF as anodic catalyst, achieving self-powered hydrogen production at the rate up to 19.6 mol h-1 m-2.

Background Cytomegalovirus (CMV) infection is associated with increased mortality in persons with HIV (PWH). It is less clear whether CMV infection is still associated with mortality when routinely screened and adequately treated. Methods This retrospective cohort study recruited 1003 hospitalized adults with HIV with CD4 cell counts Results The median (IQR) CD4 cell count of patients was 33 (13–84) cells/μL. The prevalence of CMV DNAemia was 39.8% (95% CI: 36.7–42.9%) and was significantly associated with CD4 cell count. The 182-day all-cause mortality was 9.9% (95% CI: 8.0–11.7%). Univariable analysis showed that, compared with BLQ, LVL and HVL were associated with 1.73-fold and 3.81-fold increased risks of mortality, respectively (P = .032 and P < .001). After adjustment for predefined confounding factors, HVL but not LVL was still associated with increased risk of mortality (adjusted hazard ratio: 2.63; 95% CI: 1.61–4.29; P < .001). However, for patients on effective antiretroviral therapy, the impact of HVL on 182-day mortality was not significant (P = .713). Conclusions High CMV viral load in hospitalized PWH was associated with higher mortality, even when identified early by screening. Optimalization of the management for those patients needs to be explored in future studies.

In many species of Gram-positive bacteria, SepF participated in the membrane tethering of FtsZ Z-ring during bacteria division. However, atomic-level details of interaction between SepF and FtsZ in an assembled state are lacking. Here, by combining solid-state NMR (SSNMR) with biochemical analyses, the interaction of

Platinum (Pt) is an efficient catalyst for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR), but the debate of the relevance between the Pt particle size and its electrocatalytic activity still exist. The strong metal-support interaction (SMSI) between the metal and carrier causes the charge transfer and mass transport from the support to the metal. Herein, Pt species (0.5 wt.%) with various particle sizes supported on carbon nanotubes (CNTs) have been synthesized by a photo-reduction method. The ~1.5 nm-sized Pt catalyst shows much higher HER performance than the counterparts in all pH solutions, and the mass activity of it is even 23–36 times that of Pt/C. While for ORR, the ~3 nm-sized Pt catalyst exhibits the optimal performance, and the mass activity is 3 times and even 16 times that of Pt/C in acidic and alkaline media, respectively. The high HER and ORR performances of the ~1.5 nm- and ~3 nm-sized Pt catalysts benefit from the SMSI between Pt and the CNTs matrix and the higher ratio of face sites to edge sites, which is meaningful for the design of efficient electrocatalysts for renewable energy application.

A novel Zn-Fe flow battery featuring an Fe

Both metal ions and lipid membranes have a wide distribution in amyloid plaques and play significant roles in AD pathogenesis. Although influences of different metal ions or lipid vesicles on the aggregation of Aβ peptides have been extensively studied, their combined effects are less understood. In this study, we reported a unique effect of copper ion on Aβ aggregation in the presence of lipid vesicles, different from other divalent metal ions. Cu

Fe-N-C electrocatalysts have been demonstrated to be the most promising substitutes for benchmark Pt/C catalysts for the oxygen reduction reaction (ORR). Herein, we report that N-doped carbon materials with trace amounts of iron (0-0.08 wt. %) show excellent ORR activity and durability comparable and even superior to those of Pt/C in both alkaline and acidic media without significant contribution by the metal sites. Such an N-doped carbon (denoted as N-HPCs) features a hollow and hierarchically porous architecture, and more importantly, a noncovalently bonded N-deficient/N-rich heterostructure providing the active sites for oxygen adsorption and activation owing to the efficient electron transfer between the layers. The primary Zn-air battery using N-HPCs as the cathode delivers a much higher power density of 158 mW cm

A puzzling feature of prion diseases is the cross-species barriers. The detailed molecular mechanisms underlying these interspecies barriers remain poorly understood because of a lack of high-resolution structural information on the scrapie isoform of the prion protein (PrPSc ). In this study we identified the critical role of the residues 165/167 in the barrier to seeding mouse PrP (mPrP) fibril seeds to human cellular prion protein (PrPC ). Solid-state NMR revealed a C-terminal β-sheet core spanning residues 165-230 and the packing arrangement of mPrP fibrils. Residues 165/167 are located on one end of the fibril core. Molecular dynamics simulations demonstrated that the stabilities of the seeding-induced β-strand structures are significantly impacted by hydrogen bonds involving the side chain of residue 167 and steric resistance involving residue 165. These findings suggest that the α2-β2 loop containing residues 165/167 could be the initial site of seed-template conformational conversion.

To explore the efficacy and related prognostic factors of acute myeloid leukemia (AML) in children except acute promyelocytic leukemia (APL).The clinical data of 89 non-APL children with AML treated in our hospital were retrospectively analyzed. The remission status was analyzed after chemotherapy, the long-term survival was evaluated using the Kaplan-Meier method, and the influencing factors for the prognosis were detected using univariate and multivariate Cox regression analyses.Complete remission (CR) was realized in 71 cases (79.8%) after the first course of treatment, 13 cases (14.6%) after the second course of treatment, and 5 cases (5.6%) after the third course of treatment. The 5-year event-free survival (EFS) rate and overall survival (OS) rate were 53.9% and 66.3%, respectively. The children were divided into low-risk group (n=31), middle-risk group (n=36) and high-risk group (n=22). In the three groups, the 5-year OS rate was 74.2%, 72.2% and 45.5%, respectively, while the 5-year EFS rate was 67.7%, 55.6% and 31.8%, respectively. Extramedullary infiltration at the time of initial diagnosis [HR=3.313 (95% CI: 1.748-13.664)], CD56+ [HR=1.592 (95% CI: 1.172-2.255)] and recurrence time1 year [HR=3.040 (95% CI: 1.087-5.508)] were independent risk factors affecting the prognosis, and CR achieved after the first course [HR=0.786 (95% CI: 0.228-0.803)] was an independent factor improving the prognosis of patients.The prognosis is poor in non-APL children with AML who have extramedullary infiltration at the time of initial diagnosis, CD56+ and recurrence time1 year, and CR achieved after the first course is an independent factor improving the prognosis of patients. The long-term EFS rate is significantly lower in high-risk group than that in low- and middle-risk groups. Intensive chemotherapy or early hematopoietic stem cell transplantation should be performed for high-risk patients.

Cytoplasmic inclusion of TAR DNA-binding protein 43 (TDP-43) is a hallmark of most ALS (amyotrophic lateral sclerosis) and FTLD (Frontotemporal dementia), yet the aggregation of TDP-43 remains unclear. In this study, we proved the existence of amyloid-like structures of C-terminal domain of TDP-43 (TDP-C) in bacterial inclusion bodies (IBs), and obtained a homogenous fibril sample by seeding from the components of aggregated TDP-C in Escherichiacoli IBs. The results from solid-state NMR spectroscopy suggest that the homogenous fibrils were seeded from a tiny amount of aggregated TDP-C compositions in IBs; the structure characteristics of the rigid fibril core are identified of β-rich structures, and show subtle relativity with the hydrophobicity of residues. Our study here provides a further understanding of TDP-43 protein aggregation and fibrillation.

Introduction The aim of this study was to evaluate the effectiveness of nonsurgical secondary prophylaxis interventions for esophageal varices (EV) rebleeding in cirrhotic patients using network meta-analysis. Materials and methods Secondary prophylaxis of EV rebleeding in cirrhosis is searched on PubMed, Embase, and the Cochrane Library databases. The quality of literatures was extracted by 2 independent investigators according to the requirements of Cochrane Handbook for Systematic Reviews of Interventions, Version 5.0.0. Meta-analysis was performed on Review Manager 5.3 software for the incidence of cirrhosis EV rebleeding, rebleeding-related mortality, and overall mortality; and STATA 15.1 software was used for network meta-analysis. Results In all, 57 randomized controlled trials were reviewed. Endoscopic band ligation (EBL)+argon plasma coagulation has not been recommended by guidelines, and it is rarely used; the number of existing studies and the sample size are small. Considering poor stability of the combined results, these studies were excluded; 55 literatures were included. In terms of reducing the incidence of rebleeding, transjugular intrahepatic portosystemic shunt (TIPS) surface under the cumulative ranking curve (SUCRA) (94.3%) was superior to EBL+endoscopic injection sclerotherapy (EIS) (84.4%), EIS+β-blockers (77.9%), EBL (59.8%), EBL+β-blockers+isosorbide-5-mononitrate (52.7%), EBL+β-blockers (51.4%), EIS (34.2%), β-blockers+isosorbide-5-mononitrate (23.7%), β-blockers (20.8%), and placebo (0.8%). In reducing rebleeding-related mortality, TIPS SUCRA (87.2%) was more efficacious than EBL+EIS (83.5%), EIS (47.9%), EBL+β-blockers (47.4%), β-blockers (41.8%), EBL (34.5%), and placebo (7.6%). In reducing overall mortality, TIPS SUCRA (81.1%) was superior to EBL+EIS (68.9%), EIS+β-blockers (59.2%), EBL+β-blockers (55.4%), EIS (48.8%), EBL (48.7%), β-blockers (34.2%), placebo (3.6%). Conclusions TIPS was more effective in reducing the incidence of cirrhosis EV rebleeding, rebleeding-related mortality, and overall mortality in cirrhosis. Combined with the above results, TIPS is more likely to be recommended as a secondary prophylaxis intervention for EV in cirrhosis.

Gastric cancer (GC) patients have high mortality due to late-stage diagnosis, which is closely associated with lymph node metastasis. Exploring the molecular mechanisms of lymphatic metastasis may inform the research into early diagnostics of GC. In the present study, we obtained RNA-Seq data from The Cancer Genome Altas and used Limma package to identify differentially expressed genes (DEGs) between lymphatic metastases and non-lymphatic metastases in GC tissues. Then, we used an elastic net-regularized COX proportional hazard model for gene selection from the DEGs and constructed a regression model composed of 28-gene signatures. Furthermore, we assessed the prognostic performance of the 28-gene signature by analyzing the receive operating characteristic curves. In addition, we selected the gene PELI2 amongst 28 genes and assessed the roles of this gene in GC cells. The good prognostic performance of the 28-gene signature was confirmed in the testing set, which was also validated by GSE66229 dataset. In addition, the biological experiments showed that PELI2 could promote the growth and metastasis of GC cells by regulating vascular endothelial growth factor C. Our study indicates that the identified 28-gene signature could be considered as a sensitive predictive tool for lymphatic metastasis in GC.

Developing highly efficient noble metal-free electrocatalysts for hydrogen oxidation reaction (HOR) and oxygen reduction reaction (ORR) in alkaline exchange membrane fuel cells (AEMFCs) is of great importance for the large-scale applications, which, however, still remains a great challenge. Here we present the synthesis of SnO2 and CeO2 nanoparticle-decorated mesoporous ZSM-5 (denoted as SnCe-ZSM) via electrostatic interaction, which, surprisingly, not only exhibits excellent catalytic activity towards HOR, but also largely enhance ORR performance. The strong electronic interaction between SnO2 and CeO2 nanoparticles synergistically leads to the electron-enrichment on SnO2 and oxygen vacancy accumulation on CeO2, which respectively enable the hydrogen and oxygen adsorption/activation concurrently, finally resulting in the significant enhancements of the electrocatalytic activity towards both HOR and ORR. Additionally, the SnCe-ZSM based zinc-air battery exhibits a remarkably high power density of 98 mW/cm2 and excellent stability during discharging/charging cyclic tests for 60 h. The SnCe-ZSM electrocatalyst provides a significant paradigm for designing bifunctional composite catalysts for applications in clean energy devices.

A hallmark of Alzheimer’s, Parkinson’s, and other amyloid diseases is the assembly of amyloid proteins into amyloid aggregates or fibrils. In many cases, the formation and cytotoxicity of amyloid assemblies are associated with their interaction with cell membranes. Despite studied for many years, the characterization of the interaction is challenged for reasons on the multiple aggregation states of amyloid-forming proteins, transient and weak interactions in the complex system. Although several strategies such as computation biology, spectroscopy, and imaging methods have been performed, there is an urgent need to detail the molecular mechanism in different time scales and high resolutions. This review highlighted the recent applications of fluorescence, solution and solid-state NMR in exploring the interactions between amyloid protein and membranes attributing to their advantages of high sensitivity and atomic resolution.

Developing high-efficiency hydrogen evolution reaction (HER) catalysts is of great interest for the large-scale high-purity hydrogen production, which, unfortunately, is largely blocked by the sluggish kinetics of the electro-chemical dissociation step of water molecules. Herein, a MOF-derived method has been developed to prepare Ru nanoparticles-anchored sponge-like WNO embedded in N-doped carbon layers (Ru@WNO-C). The fabricated catalyst Ru@WNO-C (Ru: 0.9 wt%) shows excellent HER catalytic activity and long-term stability with the overpotentials of 172, 358 and 24 mV at 10 mA/cm2 in 0.5 M H2SO4, 1 M Na2SO4 and 1 M KOH, respectively. More impressively, the overpotentials, especially in neutral medium, decrease markedly during the durability tests owing to the catalyst structure activation after residual Zn species leaching. The enhanced catalytic activity of Ru@WNO-C during operation is mainly attributed to the in-situ electron donation from Ru to W, leading to the easier cleavage of highly polarized H‒OH bond of water molecules and thus endowing Ru@WNO-C with excellent HER catalytic performance in non-acidic solution.

Recombinant expression in Escherichia coli allows the simple, economical, and effective production of bioactive peptides. On the other hand, the production of native peptides, particularly those rich in disulfide bonds, is a major problem. Previous studies have reported that the use of carrier proteins for fusion expression can result in good peptide yields, but few are folded correctly. In this study, two transmembrane small proteins in E. coli, YoaJ and YkgR, which both orientate with their N-termini in cytoplasm and their C-termini in periplasm, were used for fusion expression. The recombinant production of two peptides, asteropsin A (ASPA) and β-defensin (BD), was induced in the periplasm of E. coli using a selected carrier protein. Both peptides were expressed at high levels, at yields of approximately 5-10 mg/L of culture. Mass spectrometry showed that the resulting peptide had the same molecular weight as their natural forms. After purification, single peaks were observed by reversed phase high-performance liquid chromatography (RP-HPLC), demonstrating the absence of isoforms. Furthermore, cytoplasmically expressed fusion proteins with a carrier at their C-termini did not contain disulfide bonds. This study provides new carrier proteins for fusion expression of disulfide bond-rich peptides in E. coli.

The estrogen receptor (ER) and aryl hydrocarbon receptor (AhR) are ligand-activated transcription factors involved in estrogen or xenobiotic exposure, whereas the 90-kDa heat shock protein (HSP90), which is a ubiquitously expressed molecular chaperone, is involved in the signal transduction process. Although the interactions between these pathways have been under investigation, the mechanisms are unclear and the potential role of HSP90 in these interactions has not been reported. The results of goldfish primary hepatocytes showed that exposure to PCB77 and 17β-estradiol (E2) alone induced significant protein expression of cytochrome P450 1A (CYP1A) and vitellogenin (VTG), respectively. On the other hand, the combined exposure to PCB77 and E2 led to the reduction of CYP1A and VTG compared to the single treatments. Although the AhRs and ERs were naturally induced during the co-treatment, the total amount of HSP90 binding to the receptors was not changed. Furthermore, while the HSP90 chaperon activity was blocked by the specific inhibitor (geldanamycin), reciprocal inhibition between AhR and ER pathways was not observed. These findings indicate a potential role of HSP90 where competition between AhR and ER for binding to HSP90 can occur and cause reciprocal inhibition.

The activation of heat shock factor 1 (HSF1) can be induced by the changes in environmental pH, but the mechanism of HSF1 activation by acidification is not completely understood. This paper reports that a low pH (pH~6.0) can trigger human HSF1 activation. Considering the involvement of the imidazole group of histidine residues under acid pH stress, an in vitro EMSA experiment, Trp-fluorescence spectroscopy, and protein structural analysis showed that the residue, His83, is the essential for pH-dependent human HSF1-activation. To determine the roles of His83 in the HSF1-mediated stress response affecting the cellular acid resistance, mouse embryo fibroblasts with normal wild-type or mutant mouse HSF1 expression were preconditioned by heating or pH stress. The results suggest that His83 is essential for HSF1 activation or the HSF1-mediated transcription of heat shock proteins, in protecting cells from acid pH stress.

Contamination by heavy metals and sex hormones in a water environment is an important health issue. In this study, we investigated the estrogenic effects of cadmium (Cd) administration alone and in combination with 17beta-estradiol (E2) on the hepatocytes of male Bullfrog (Rana catesbeiana). Their vitellogenin (VTG) expression and reactive oxygen species (ROS) were analyzed upon exposure to Cd alone or to both Cd and E2. Our results suggest that the VTG levels induced by the co-treatment of 100 nM E2 and 100 nM CdCl2 were significantly higher than those induced by 100 nM E2 alone (p < 0.05), and were comparable to vitellogenin induction observed with 1 μM E2. A similar result was observed by western blot analysis in the culture medium of hepatocytes. Meanwhile, Cd (but not E2) increased the ROS levels. These results suggest that Cd has a cooperative effect with E2 in the induction of VTG, thus acting as an estrogenic disruptor. Cd also causes oxidative stress that occurs with the enhanced vitellogenesis.

Cytochrome P4501A (CYP1A) has attracted an increasing interest due to its important role in metabolism of contaminants in aquatic environment and kinds of biomarkers to monitor the pollutants. CYPs are reported to express in E. coli, yeast and insect cells, while expression levels in these systems are too low to continue further study, such as functional and structural research. In this study, we construct an expression system using Shewanella oneidensis to produce goldfish CYP1A. RBS sequence that can elevate expression level by initiating the translation was added. A leading signal peptide which will direct the goal protein into periplasm of the host was introduced. Moreover, large-size plasmid construction strategy was applied during the successful construction process of expression system. At the position of ~60 kDa, a single band was seen clearly after expression; furthermore the amount of expressed CYP1A was as high as 0.02 micromoles per liter in the culture. Heme test was also performed, the result showed the typical P450 hemoprotein spectra. All these data suggest the possible suitable expression system for fish P4501A system was constructed.

E-mail: jaspark@pusan.ac.krReceived July 6, 2012, Accepted September 6, 2012Key Words : Human heat shock factor 1, Tryptophan-fluorescence spectroscopy, Acid pH, HistidineThe cellular response to acute and proteotoxic stresses,historically called “heat shock response” (HSR), is stronglyconserved throughout all known organisms.

Heat shock proteins (HSPs) are synthesized rapidly in response to a variety of physiological or environmental stressors, whereas the transcriptional activation of HSPs is regulated by a family of heat shock factors (HSFs). In vertebrates, multiple HSFs (HSF1-4) have been reported to have different roles in response to a range of stresses. This paper reports the cDNA cloning of two goldfish (Carassius auratus) HSF gene families, HSF1 and three isoforms of HSF2. Both HSF1 and HSF2s showed high homology to the known HSFs from other organisms, particularly the zebrafish. Different patterns of HSF1 and HSF2 mRNA expression were detected in several goldfish tissues, highlighting their distinct roles. In cadmium (Cd)-treated tissues, the responses of HSP70 showed less difference. However, the increase in HSF1 and HSF2 in these tissues differs considerable. In particular, HSF2 was induced strongly in the heart and liver. On the other hand, in heart tissue, HSF1 showed the smallest increment. These results suggest the potential role of HSF2 in assisting HSF1 in these tissues. In another in vitro experiment of hepatocyte cultures, Cd exposure caused similar patterns of goldfish HSF1 and HSF2 mRNA expression and induction of the HSP70 protein. On the other hand, an examination of the characterization of recombinant proteins showed that HSF1 undergoes a conformation change induced by heat shock above 30 °C and approaches each other in the trimer, whereas HSF2 could not sense thermal stress directly. Furthermore, immune-blot analysis of HSFs showed that both monomers and trimmers of HSF1 were observed in cadmium-induced tissues, whereas HSF2 were all in monomeric. These results show that HSF1 and HSF2 play different roles in the transcription of heat shock proteins.

Cytochrome P4501A (CYP1A) in fish has attracted an increasing interest because of its important roles in the metabolic activation of certain xenobiotics such as aromatic hydrocarbons. CYPs are reported to be expressed in yeast, insect cells and Escherichia coli , but are critical for high-level expression. Besides, this study found that the purification of recombinant goldfish CYP1A would result in a loss of enzyme activity. Because large quantities of functional CYP1A are required, it is necessary to find a suitable host with high-level expression. In the present study, a novel expression system using Shewanella oneidensis was established successfully for the production of goldfish CYP1A. A signal peptide in the expression vector leads to the high-level expression in the periplasmic space of Shewanella . The recombinant CYP1A in S hewanella reached up to 1 μmol per liter of culture, and showed the typical P450 hemoprotein spectra. An ethoxyresorufin O -deethylase assay revealed the amount of functional proteins in Shewanella to be almost ten times more than those in other expression systems. Furthermore, the CYP1A-mediated degradation of benzo[ a ]pyrene was also observed by 1 H NMR spectroscopy. These results indicate the possible application of periplasmic fractions to obtain sufficient quantities of functional CYP1A for further studies.

In bony fish or other aquatic vertebrates, the aryl hydrocarbon receptor (AhR) signaling pathway is initiated by exposure to polycyclic (or/and halogenated) aromatic hydrocarbons (PAHs, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD), which subsequently induces the up-regulated expression of a series of related genes (such as cytochrome P4501A (CYP1A)). However, a lack of applicable protein reagents hinders our further understanding of the AhR signaling pathway, which focuses only on gene-based investigations. The goldfish (Carassius auratus) is an ideal model for a study of environmental pollution in whole-Asian fresh water. Here, three sensitive and specific polyclonal antisera against goldfish AhR1, AhR2, and CYP1A proteins were developed. These antisera not only bound the in-vitro synthesized target proteins, but recognized the real proteins expressed in goldfish tissues, with minimal cross-reactivity to non-specific proteins. Together with the analysis of semi-quantitative RT-PCR and polyclonal-antibody-based sandwich ELISA, we confirmed that goldfish AhRs differed in the expression (mRNA and protein levels) patterns among test tissues. Importantly, the relative abundance of each AhR mRNA levels from the different tissues showed no obvious consistency with their protein levels. After exposure to TCDD, goldfish AhR2 showed a more sensitivity than AhR1, and stimulated CYP1A expression directly, similar with the other reported fish models. Overall, development of these antibodies in this study will allow valuable and versatile investigations to further understand the AhR signaling pathway, and different expression (mRNA and protein) patterns represent the first step in determining the regulatory mechanisms underlying the TCDD-exposed aquatic environment.

Metal ions existing in the environment could influence the estrogen pathway in aquatic animal, but the detailed mechanism is still delusive. We here showed that in male Carassius auratus hepatocytes, copper (Cu) or cadmium (Cd), did not directly induce vitellogenin (VTG) expression. Interestingly, co-exposure with Cd 2+ (or Cu 2+ ) and 17-β-estradiol (E2) greatly increased the VTG level, comparing with single treatment of E2. Meanwhile, Cd 2+ or Cu 2+ (but not E2) triggers HSP70 expression. But, mixture of Cd 2+ or Cu 2+ with E2 did not obviously raise HSP70 level. E2 also had no obvious effect on reactive oxygen species. Co-treatment of Cd 2+ and E2 showed no obvious increase compared to single treatment with Cd 2+ . We further assume that Cd 2+ -involved oxidative stress generates misfolded proteins, resulting in the competition of HSP70 proteins from a heterocomplex (with estrogen receptor). Thus, dissociation of the heterocomplex actives the receptor–ligand binding activity and promotes the E2-induced VTG expression.