Chronic PFOS exposures induce life stage-specific behavioral deficits in adult zebrafish and produce malformations in F1 offspring

Perfluorooctanesulphonicacid (PFOS) is an organic contaminant that is ubiquitous in the environment, wildlife, and humans. Few studies have assessed the effects of chronic PFOS exposure on central nervous system function in aquatic organisms. The present study defined the behavioral effects of varying life span chronic exposures to low dose PFOS in zebrafish. The zebrafish were treated with vehicle control or 0.5μM PFOS during 1-21, 21-120, or 1-120 day post fertilization (dpf). Chronic PFOS exposure impaired the adult zebrafish behavior mode under the tapping stimulus. The movement speed of 1-120 dpf exposed fish was significantly increased compared with control, while 1-21 and 21-120 dpf exposed groups were not severely affected. PFOS residues in F1 embryos derived from parental exposure during both the 1-120 and 21-120 dpf groups was significantly higher than control, and F1 embryos in these two groups showed obvious malformations, such as uninflated swim bladder (USB) and bent spine (BS). Larvae of the parental exposed to PFOS from 1-21 or 21-120 dpf elicited a higher swim rate than control in both the light and dark periods. Embryos derived from the 1-120 dpf group showed a statistically lower speed in the light period and a higher speed in the dark period as compared with control. Though there is little PFOS residue in 1-21 dpf group, the adverse behavioral effects on both adult and F1 larvae indicate that exposure during the first 21 dpf induce long-term neurobehavior toxicity. Our findings demonstrate that chronic exposure to low dose PFOS in different life stage adversely impacts adult behavior, subsequent offspring malformation, and larval behavior.This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Society of Environmental Toxicology and Chemistry and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291552-8618.,Additional authors (Liu, Xiaojuan and Zhu, Guonian) appear and the author order is revised on the published version of this article.Keywords: perfluorooctanesulfonic acid, zebrafish embryo, chronic exposure, behavio

Early life perfluorooctanesulphonic acid (PFOS) exposure impairs zebrafish organogenesis

Additional authors (Zengxin Gai and Xue Ma) appear and the author order is revised on the published version of this article.As a persistent organic contaminant, perfluorooctanesulphonic acid (PFOS) has been widely detected in the environment, wildlife, and humans. The present study revealed that zebrafish embryos exposed to 16 µM PFOS during a sensitive window of 48-96 hour post-fertilization (hpf) disrupted larval morphology at 120 hpf. Malformed zebrafish larvae were characterized by uninflated swim bladder, less developed gut, and curved spine. Histological and ultrastructural examination of PFOS-exposed larvae showed structural alterations in swim bladder and gut. Whole genome microarray was used to identify the early transcripts dysregulated following exposure to 16 µM PFOS at 96 hpf. In total, 1,278 transcripts were significantly misexpressed (p < 0.05) and 211 genes were changed at least two-fold upon PFOS exposure in comparison to the vehicle exposed control group. A PFOS-induced network of perturbed transcripts relating to swim bladder and gut development revealed that misexpression of genes were involved in organogenesis. Taken together, early life stage exposure to PFOS perturbs various molecular pathways potentially resulting in observed defects in swim bladder and gut development.This is an author's peer-reviewed manuscript. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquatic-toxicology/.Keywords: Perfluorooctanesulfonic acid, Zebrafish embryo, Developmental toxicity, Swim bladder, GutKeywords: Perfluorooctanesulfonic acid, Zebrafish embryo, Developmental toxicity, Swim bladder, Gu

Reproductive toxicity of low level bisphenol A exposures in a two-generation zebrafish assay: Evidence of male-specific effects

Bisphenol A (BPA), a high-volume chemical used to make polycarbonate plastic and epoxy resins, is a ubiquitous contaminant in environment and human body. To investigate the reproductive effects of long-term exposure to low concentrations of BPA, a two-generation study was conducted using the aquatic model species of zebrafish. Our findings revealed that exposure to 1 nM (0.228 μg/L) BPA for continuous two generations resulted in female-biased sex ratio in both F1 and F2 adult population, decreased sperm density, and decreased sperm quality as measured by motility, velocity, ATP content and lipid peroxidation in F1 and F2 males. Females were less sensitive to BPA exposures than males as no adverse effects were found in female gonads or gametes. Delayed hatching at 48 hpf and increased malformation and mortality were found in the offspring from BPA exposed F2, but not F1 parents. Most importantly, the adverse effect on larval development and survival from BPA exposed F2 parents was paternal-specific, resulting mainly from BPA exposed males. Subsequent transcription analysis of F2 male gonads revealed dysregulated mitochondrial biogenesis and significant activation of non-canonical Wnt/planar cell polarity and Wnt/Calcium signaling pathways. Gene expression analysis of larvae from BPA exposed F2 parents showed significant reduced expression of DNA methyltransferases such as dnmt1, dnmt3, and dnmt5. In conclusion, low level BPA exposures for continuous two generations not only affects sex ratio and sperm quantity/quality in F1 and F2 adults, reproductive success in offspring from F2 parents, but also perturbs various molecular pathways potentially contributing to these BPA induced male-specific reproductive defects.This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquatic-toxicology/Keywords: Wnt signaling, BPA, Zebrafish, Chronic exposure, Sperm, Mitochondrial biogenesisKeywords: Wnt signaling, BPA, Zebrafish, Chronic exposure, Sperm, Mitochondrial biogenesi

Distribution law of temperature changes during methane adsorption and desorption in coal using infrared thermography technology

Gas adsorption and desorption is a thermodynamic process that takes place within coal as temperature changes and that is related to methane (CH4) storage. As infrared thermographic technology has been applied in this context to measure surface temperature changes, the aim of this research was to further elucidate the distribution law underlying this process as well as the thermal effects induced by heat adsorption and desorption in coal. Specimens of two different coal ranks were used in this study, and the surface temperature changes seen in the latter were detected. A contour line map was then drawn on the basis of initial results enabling a distribution law of temperature changes for samples. The results show that different regions of coal sample surfaces exhibit different heating rates during the adsorption process, but they all depends on gas storage capacity to a certain extent. It proposes a correlation coefficient that expresses the relationship between temperature change and gas adsorption capacity that could also be used to evaluate the feasibility of coalbed CH4 extraction in the field. And finally, this study is deduced a method to reveal the actual adsorption capacity of coal or CH4 reservoirs in in situ coal seams

Linking Land Use Metrics Measured in Aquatic–Terrestrial Interfaces to Water Quality of Reservoir-Based Water Sources in Eastern China

The effects of anthropogenic land use on the water quality of reservoir-based water sources are understudied. We trained a self-organizing map (SOM) to measure the spatial pattern of nutrients over the course of a year in 61 reservoirs located in eastern China. In the linear regression model and one-way analyses of variance, we found that water quality was influenced by period of the year (flood, low, and normal periods based on rainfall conditions) and reservoir altitude (plains vs. mountains). Our results indicated that land use metrics measured in aquatic&ndash;terrestrial interfaces significantly influenced the water quality of reservoirs. The land use intensity (LUI) and the proportion of construction land had a positive correlation with ammonia nitrogen (NH3-N) and chemical oxygen demand (CODMn) concentrations, and redundancy analysis indicated that the percent of landscape (PLAND) represented by construction land was positively correlated with CODMn, NH3-N, total phosphorus (TP), and total nitrogen (TN) concentrations. The proportion of cropland was not correlated with any water quality property except for CODMn concentration. The total explained variance for water quality was highest when the scale was large (the area defined by a 1500 m radius around the reservoir), indicating that management which ensures water safety should be carried out at this scale

Characteristics and possible mechanisms of 46, XY differences in sex development caused by novel compound variants in NR5A1 and MAP3K1

Abstract Background Dozens of genes are involved in 46, XY differences in sex development (DSD). Notably, about 3/4 of patients cannot make a clear etiology diagnosis and single gene variant identified cannot fully explain the clinical heterogeneity of 46, XY DSD. Materials and methods We conducted a systematic clinical analysis of a 46, XY DSD patient, and applied whole-exome sequencing for the genetic analysis of this pedigree. The identified variants were analyzed by bioinformatic analysis and in vitro studies were performed in human embryonic kidney 293T (HEK-293T) cells which were transiently transfected with wild type or variant NR5A1 and MAP3K1 plasmid. Furthermore, protein production of SRY-box transcription factor 9 (SOX9) was analyzed in cell lysates. Results A novel NR5A1 variant (c.929A > C, p. His310Pro) and a rare MAP3K1 variant (c.2282T > C, p. Ile761Thr) were identified in the proband, whereas the proband's mother and sister who only carry rare MAP3K1 variant have remained phenotypically healthy to the present. These two variants were predicted to be pathogenic by bioinformatic analysis. In vitro, NR5A1 variant decreased the SOX9 production by 82.11% compared to wild type NR5A1, while MAP3K1 variant had little effect on the SOX9 production compared to wild type MAP3K1. Compared to wild type NR5A1 transfection, the SOX9 production of cells transfected with both wild type plasmids decreased by about 17.40%. Compared to variant NR5A1 transfection, the SOX9 production of cells transfected with both variant plasmids increased by the 36.64%. Conclusions Our findings suggested the novel compound variants of NR5A1 and MAP3K1 can alter the expression of SOX9 and ultimately lead to abnormality of sex development

The Enrichment and Distribution of Trifloxystrobin in Medaka Fish

In order to evaluate the safety of trifloxystrobin in environment and non-target organisms, the enrichment and distribution of trifloxystrobin in Medaka (Oryzias latipes) were studied in this experiment. Medaka were exposed in the water containing 0.1 μg/L, 1 μg/L, 10 μg/L and 100 μg/L trifloxystrobin continuously for 21 days. The results indicated that in female, the concentration order was as follows: fat > liver > intestine > gonad > flesh; in male, the concentration order was as follows: fat > intestine > liver > flesh in the low concentration exposure group with 0.1 μg/L and 1 μg/L, while the concentration order was as follows: fat > liver > intestine > flesh in the high concentration exposure group with 10 μg/L and 100 μg/L. This study provides important data support and theoretical basis for predicting the behavior of trifloxystrobin in the environment, evaluating the environmental safety of trifloxystrobin and guiding the use of drugs

Identification, characterization and expression analysis of the VQ motif-containing gene family in tea plant (Camellia sinensis)

Abstract Background VQ motif-containing (VQ) proteins are plant-specific proteins that interact with WRKY transcription factors and play important roles in plant growth, development and stress response. To date, VQ gene families have been identified and characterized in many plant species, including Arabidopsis, rice and grapevine. However, the VQ gene family in tea plant has not been reported, and the biological functions of this family remain unknown. Results In total, 25 CsVQ genes were identified based on the genome and transcriptome of tea plant, and a comprehensive bioinformatics analysis was performed. The CsVQ proteins all contained the typical conserved motif FxxhVQxhTG, and most proteins were localized in the nucleus. The phylogenetic analysis showed that the VQ proteins were classified into 5 groups (I, III-VI); the evolution of the CsVQ proteins is consistent with the evolutionary process of plants, and close proteins shared similar structures and functions. In addition, the expression analysis revealed that the CsVQ genes play important roles in the process of tea plant growth, development and response to salt and drought stress. Furthermore, a potential regulatory network including the interactions of CsVQ proteins with CsWRKY transcription factors and the regulation of upstream microRNA that is closely related to the above-mentioned processes is proposed. Conclusions The results of this study increase our understanding and characterization of CsVQ genes and their encoded proteins in tea plant. This systematic analysis provided comprehensive information for further studies investigating the biological functions of CsVQ proteins in various developmental processes of tea plants

A Method to Deduce and Synthesize the Dafny Programs

We propose a systematic method to deduce and synthesize the Dafny programs. First, the specification of problem is described in strict mathematical language. Then, the derivation process uses program specification transformation technology to perform equivalent transformation. Furthermore, Dafny program is synthesized through the obtained recursive relationship and loop invariants. Finally, the functional correctness of Dafny program is automatically verified by Dafny verifier or online tool. Through this method, we deduce and synthesize Dafny programs for many typical problems such as the cube sum problem, the minimum (or maximum) contiguous subarray problems, several searching problems, several sorting problems, and so on. Due to space limitation, we only illustrate the development process of Dafny programs for two typical problems: the minimum contiguous subarray problem and the new local bubble sorting problem. It proves that our method can effectively improve the correctness and reliability of Dafny program developed. What’s more, we demonstrate the potential of the deductive synthesis method by developing a new local bubble Sorting program

Genome-Wide Identification, Classification and Expression Analysis of the HSP Gene Superfamily in Tea Plant (Camellia sinensis)

Heat shock proteins (HSPs) function as molecular chaperones. These proteins are encoded by a multigene family whose members play crucial roles in plant growth, development and stress response. However, little is known about the HSP gene superfamily in tea plant. In this study, a total of 47 CsHSP genes were identified, including 7 CsHSP90, 18 CsHSP70, and 22 CssHSP genes. Phylogenetic and composition analyses showed that CsHSP proteins in the same subfamily have similar gene structures and conserved motifs, but significant differences exist in the different subfamilies. In addition, expression analysis revealed that almost all CsHSP genes were specifically expressed in one or more tissues, and significantly induced under heat and drought stress, implying that CsHSP genes play important roles in tea plant growth, development, and response to heat and drought stress. Furthermore, a potential interaction network dominated by CsHSPs, including HSP70/HSP90 organizing protein (HOP) and heat shock transcription factor (HSF), is closely related to the abovementioned processes. These results increase our understanding of CsHSP genes and their roles in tea plant, and thus, this study could contribute to the cloning and functional analysis of CsHSP genes and their encoded proteins in the future