Download or read book Development and Use of a Teleost Model Medaka Oryzias Latipes for Detection of Xenobiotic Induced Reproductive Toxicity written by Cory Scott Koger and published by . This book was released on 2002 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2003 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book American Doctoral Dissertations written by and published by . This book was released on 2002 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Xenobiotics in Aquatic Animals written by Mohd Ashraf Rather and published by Springer Nature. This book was released on 2023-05-10 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the latest understanding of the impact of xenobiotics on the developmental and reproductive processes of aquatic animals, particularly nektonic forms, which comprise an important group of aquatic ecosystems. Aquaculture is quickly becoming the largest contributor of fish protein for human consumption. As the aquaculture business expands, farmed fish will be exposed to more environmental toxins, necessitating the use of chemical therapeutic drugs for fish. This book brings together experts on the regulation of environmental toxins and food chemicals from around the world, as well as researchers looking into the metabolism and disposal of foreign chemicals (xenobiotics) in fish species. The impact of xenobiotics on reproductive and developmental biology of all living forms has become of prime importance at the current time. As the effect of these xenobiotics on aquatic animals is an emerging area for research and development, several groups across the world are working on these aspects, targeting different groups of fishes in both marine and freshwater ecosystems. This collective work highlights several key and updated recent aspects of different types of xenobiotics entering aquatic ecosystems, impacts of these agents on reproductive physiology, developmental biology, breeding biology, hormonal imbalance, aquatic ecology, and pollution on the aquatic ecosystem. The unique aggregation of different types of stressors to aquatic animals under a single volume will be a useful reference for readers, including scientists, teachers, students, researchers and policymakers and those involved in aquaculture and environment conservation.
Download or read book Biomarkers for Stress in Fish Embryos and Larvae written by Irina Rudneva and published by CRC Press. This book was released on 2013-08-28 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present work evaluates the toxic effects of some environmental stressors on fish eggs and larvae and describes the biomarker responses of fish from locations with varying levels of pollution. Development of the main groups of biomarkers is discussed. The book demonstrates general trends and specific peculiarities of biomarker induction in early
Download or read book Transgenerational and Epigenetic Effects of Developmental Exposure to Atrazine on Medaka Oryzias Latipes written by Jacob Alexander Cleary and published by . This book was released on 2018 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Exposure to environmental chemicals can cause epigenetic transgenerational inheritance of altered phenotypes. Chemicals such as the plasticizer bisphenol-A (BPA), the fungicidal vinclozolin, and the oral contraceptive component 17a-ethinylestradiol (EE2) induce epigenetic changes in various species. Each of these chemicals is an environmentally pervasive endocrine disrupting compound, as is the case with the abundantly used herbicide atrazine, whose endocrine disrupting mechanisms still remain unclear. Atrazine (ATZ) is presently one of the most abundantly used herbicides in the United States, and a common contaminant of natural water bodies and drinking waters in high-use areas. ATZ belongs to the triazine herbicides which specifically target photosynthetic tissues, yet ATZ can affect animal health. Fish exposed to ATZ and EE2 display dysregulation of reproductive processes, which include alterations to the hypothalamic-pituitary-gonadal (HPG) axis pathways. However, the potential for ATZ-induced transgenerational inheritance of reproductive dysfunction has not been investigated in fish. The transgenerational reproductive consequences of ATZ exposure have been explored in rats, but fish are among the species at greatest risk from ATZ exposure, therefore, I chose a model species to represent this environmentally relevant scenario. In the present study I analyzed the effects of ATZ and EE2 exposures during early development on transgenerational reproductive dysregulation in Japanese medaka (Oryzias latipes). F0 medaka were exposed to ATZ, EE2, and a solvent during the first twelve days of development with no exposure over the subsequent three generations. These early developmental exposures overlap with the critical windows of embryonic germ cell development, gonadogenesis, and sex determination when gonadal DNA methylation is being reprogrammed. Exposed males and females of the F0 treatment lineages were bred to produce the F1 generation, the F1 offspring were bred to produce the F2 generation, and the F2 offspring were bred to produce the F3 generation. Neither ATZ nor EE2 altered sperm parameters, gonadosomatic, or hepatosomatic indices in the treated F0 generation. However, the hepatosomatic index was reduced in F2 females derived from F0 fish treated with either ATZ or EE2. Hepatosomatic and gonadosomatic indices are ratios of liver and gonad weights to the total weight of the fish, which are cursory metrics for evaluating energetic and reproductive health. The fecundity of F0 and F2 fish was unaffected by exposure to ATZ or EE2; however, the fertilization rate was decreased among the F2 fish derived from the low ATZ and low EE2 treated F0 generation. Moreover, there were significant transgenerational differences in the expression of reproductive regulatory genes and genes required for DNA methylation. Genomic methylation patterns are catalyzed by DNA methyltransferase enzymes (dnmts) that regulate the heritable transcriptional activity of specific regions of DNA essential to development. Present results suggest that early life exposure to ATZ and EE2 cause no significant effects in the immediate generation, but that future generations of fish are at greater risk of reproductive dysfunction."--Abstract from author supplied metadata.
Download or read book The Toxicology of Fishes written by Richard T. Di Giulio and published by CRC Press. This book was released on 2008-02-25 with total page 1102 pages. Available in PDF, EPUB and Kindle. Book excerpt: When looking for a book on fish toxicology, you might find one that discusses the biochemical and molecular aspects, or one that focuses aquatic toxicology in general. You can find resources that cover human and animal toxicology or ecotoxicology in general, but no up-to-date, comprehensive monograph devoted to the effects of chemical pollution on
Download or read book Mechanisms of Selenomethionine and Hypersaline Developmental Toxicity in Japanese Medaka Oryzias Latipes written by Allison Justine Kupsco and published by . This book was released on 2016 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Selenium toxicity to oviparous vertebrates is often attributed to selenomethionine (SeMet), which can maternally transfer to developing embryos. The mechanism of SeMet toxicity is unclear. Furthermore, salinity of fresh waterways is increasing due to climate change and anthropogenic disturbance. Hypersalinity can potentiate SeMet toxicity to Japanese medaka (Oryzias latipes). The current study aimed to characterize the molecular mechanisms of SeMet and hypersalinity at sensitive developmental stages. Developmental toxicity of seawater was compared to desalination brine (DSB) and artificial water based on the San Joaquin River (SJR), CA. DSB toxicity was equal to seawater, while SJR water was the most toxic to embryos and larvae. Flavin-containing monooxygenases (FMOs) initiate SeMet toxicity and are induced by hypersalinity. However, developmental expression and regulation of FMOs in fish are unknown. Five putative medaka FMOs were identified with differential developmental mRNA expression patterns: two FMOs increased during mid-organogenesis; two FMOs decreased beginning at early organogenesis; and one FMO remained constant. Promoter analysis indicated regulation by developmental factors and the UPR. Treatments with UPR-inducer tunicamycin increased expression of two FMOs. In contrast, dithiothreitol inhibited the UPR and three FMOs, suggesting that FMOs are differentially regulated by the UPR. The developmental stage sensitivity of medaka embryos to SeMet was investigated in freshwater and SJR water. Stages 9-25 were most sensitive to SeMet; and hypersalinity potentiated SeMet toxicity during the onset of liver organogenesis, osmoregulation, and chondrogenesis. The mechanisms behind the potentiation of SeMet toxicity by hypersalinity indicated no involvement of oxidative stress or apoptosis; however, results suggested a role for the unfolded protein response (UPR) when animals were treated with 50[Mu]M SeMet for 12hrs. Mechanisms of SeMet-induced spinal deformities (5[Mu]M and 2.5[Mu]M for 24hrs) were further elucidated using imaging methods and showed increased oxidative stress and apoptosis in tails of embryos with spinal malformations. Gene expression analysis demonstrated a UPR activation pattern unique from UPR positive controls. Furthermore, these effects prematurely repressed chondrogenesis and induced osteogenesis. Overall, results will be useful for the risk assessment of hypersalinity and Se under hypersaline conditions; and inform studies on developmental mechanisms of toxicity.
Download or read book Xenobiotics in Fish written by D.J. Smith and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aquaculture is rapidly becoming a major source of fish protein used to meet the nutritional needs of humans. As the aquaculture industry grows, exposure of farmed fish to environmental contaminants, and the need for chemical therapeutic agents for fish, will increase. This book is designed to bring together authorities worldwide on the regulation of environmental contaminants and food chemicals and researchers investigating the metabolism and disposition of foreign chemicals (xenobiotics) in fish species.
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1989 with total page 1296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hypoxia Causes Epigenetic Changes and Transgenerational Reproductive Impairments in Marine Medaka Oryzias Melastigma written by Yuan Simon Wang and published by . This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Hypoxia Causes Epigenetic Changes and Transgenerational Reproductive Impairments in Marine Medaka (Oryzias Melastigma)" by Yuan, Simon, Wang, 王源, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Aquatic hypoxia (Certain endocrine disruptors have been shown to cause epigenetic changes and transgenerational effects in mammals and fish, including reproductive dysfunction, infertility, and abnormal development. Using marine medaka (Oryzias melastigma) as a model, this study set out to explore whether hypoxia can induce epigenetic changes and transgenerational effects on male reproduction. Experiments were conducted to unravel the effects of hypoxia at the epigenetic, genetic, protein and phenotypic levels in male fish from F0 to F2. Sexually mature F0 marine medaka were maintained under normoxia or hypoxia for one month. Eggs from the normoxic controls were continuously raised in normoxia for two generations (normoxic group). Eggs from the hypoxic treatment were divided into two batches: one batch was continuously raised under hypoxia for two generations (hypoxic group); and the other batch was returned to normoxia and raised for two generations (transgenerational group). Genomic DNA methylation was examined by liquid chromatography - tandem mass spectrometry (LCMS-MS) and genome-wide methylated DNA immunoprecipitation sequencing (MeDIP-Seq). The transcriptomic and proteomic profiles were investigated using RNA-Seq and isobaric tags for relative and absolute quantification (iTRAQ), respectively. The identified genes or proteins showing transgenerational effects were further validated by real-time qPCR and western blot analysis, respectively. Gonadosomatic index, sperm motility, the number of spermatids, fertilization success and hatching success were also measured and compared among the normoxic, hypoxic and transgenerational groups to assess phenotypic changes. F0 fish exposed to hypoxia can cause a decline in sperm motility and spermatid quantity in their F1 and F2 progenies, despite they having never been directly exposed to hypoxia. In both F0 and F2, the observed transgenerational phenotypic changes were associated with differential methylation in forkhead box protein P2 (FOXP2), euchromatic histone-lysine N-methyltransferase 2 (EHMT2) and protein tyrosine kinase 2 beta (PTK2B). The transcriptomic analysis provided further evidence that EHMT2 and PTK2B were upregulated. Elevation of dimethylated Histone H3 lysine 9 (H3K9) mediated by EHMT2 was consistently found in F0, F1 and F2, which may account for the observed reproductive impairment. The aberrant and consistent DNA methylation found in fish sperm demonstrated that hypoxia can make epigenetic marks in the germline, which can be passed on to subsequent generations, leading to transgenerational phenotypic changes. The transgenerational reproductive impairments caused by hypoxia, as revealed in this study, suggest that the detrimental effects on fish in aquatic environments have been grossly under-estimated. Because epigenetic changes and regulation of spermatogenesis are highly conserved in animals, the results of this study may imply that hypoxic stresses, res
Download or read book The Fish Oocyte written by Patrick J. Babin and published by Springer Science & Business Media. This book was released on 2007-08-20 with total page 513 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses the growing needs in deciphering the biological processes associated with fish reproduction, in view of the growth of aquaculture and the dwindling natural stocks of commercially important fish. It presents a comprehensive overview on egg production in fish, from the standpoint of the oocyte. With this view in mind, the book includes chapters on oocyte development (oogenesis), hormonal regulation and hormone receptors, formation of the egg envelopes, growth, accumulation of nutrients and maternal transcripts, maturation, hydration, ovulation and fertilization. A special emphasis is placed on using state-of-the-art tools including electron microscopy for discerning the ultra-structure of the follicle and genomic/proteomic tools to fully understand biological basis of fish reproduction. Studies on promoting oocyte maturation, ovulation and spawning in farmed fish and preservation of fish oocytes at low temperatures are also included. The book will appeal to University lecturers, students, research scientists and those associated with culture of fish in freshwater or marine aquaculture.
Download or read book Environmental Toxicology and Chemistry written by and published by . This book was released on 2007 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cumulated Index Medicus written by and published by . This book was released on 1991 with total page 1384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fish Physiology Organic Chemical Toxicology of Fishes written by Keith B. Tierney and published by Academic Press. This book was released on 2013-12-04 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fish Physiology: Organic Chemical Toxicology of Fishes discusses the different types of organic chemical contaminants and their respective toxic effects in fish. The book also covers the detection of dissolved organic compounds and methods to assess organic toxicity. Substances addressed in this book include organometallics, hydrocarbons, endocrine disrupting compounds (EDCs), insecticides, herbicides, and pharmaceuticals. Fish are exposed to an ever-increasing array of organic chemicals that find their way into rivers and oceans. Some of these compounds are no longer being produced but nonetheless persist within the environment (persistent organic pollutants, or POPs). The exposure of fish to toxic organic compounds has potential impact on human, fish, and ecosystem health. Yet the regulations that govern environmental water quality vary worldwide, and compliance is never complete. This book provides a crucial resource on these issues for researchers in zoology, fish physiology, and related fields; applied researchers in environmental monitoring, conservation biology, and toxicology; and university-level students and instructors in these areas. Organized by type of toxic organic chemicals Includes metals, POPs, EDCs, herbicides, insecticides, and pharmaceuticals Measures toxicity in a variety of ways aside from lethality Probes the toxic effects of compound mixtures as well as single pollutants
Download or read book A Risk Management Strategy for PCB Contaminated Sediments written by National Research Council and published by National Academies Press. This book was released on 2001-06-07 with total page 451 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a risk-based framework for developing and implementing strategies to manage PCB-contaminated sediments at sites around the country. The framework has seven stages, beginning with problem definition, continuing through assessment of risks and management options, and ending with an evaluation of the success of the management strategy. At the center of the framework is continuous and active involvement of all affected parties-particularly communities-in the development, implementation, and evaluation of the management strategy. A Risk-Management Strategy for PCB-Contaminated Sediments emphasizes the need to consider all risks at a contaminated site, not just human health and ecological effects, but also the social, cultural, and economic impacts. Given the controversy that has arisen at many PCB-contaminated sites, this book provides a consistent, yet flexible, approach for dealing with the many issues associated with assessing and managing the risks at Superfund and other contaminated sites.
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1989 with total page 1310 pages. Available in PDF, EPUB and Kindle. Book excerpt:
