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Sample records for zebrafish yolk membrane

  1. Morphofunctional transformations of the yolk syncytial layer during zebrafish development.

    PubMed

    Kondakova, Ekaterina Alexandrovna A; Efremov, Vladimir Ivanovich I

    2014-02-01

    The yolk syncytial layer (YSL) is a provisory extraembryonic structure of teleost fishes and representatives of some other taxa with meroblastic cleavage. The YSL of teleosts is a symplast with polymorphous polyploid nuclei. It is known to perform nutritional, morphogenetic, immune, and, probably, other functions. Data about the YSL organization, functioning and regulation is fragmentary. Although gene expression patterns and other aspects of YSL functioning have been studied in Danio rerio, the morphology of its YSL has not been described in detail. The study of zebrafish YSL structure on sequential developmental stages is necessary to recognize specific features of this important polyfunctional system in this model organism and to extend our knowledge about provisory systems. The thickness of the YSL and the distribution of its nuclei are not uniform on each stage and change during development. During oblong and sphere stages the internal YSL (I-YSL) is filled with yolk inclusions; interphase yolk syncytial nuclei (YSN) and mitotic asters can be seen. During doming and epiboly the external YSL (E-YSL) is thicker than I-YSL. On the subsequent stages the YSL is thickened caudally. The dorsal YSL part is thickened during early segmentation stages and becomes the thinnest YSL region later. The anterior part of the YSL is thin, but enlarges during larval period. The YSN of different size and diverse forms, from regular to lobed, are present and form clusters. The number of irregular-shaped nuclei increases during development. The YSL thickens in the end of endotrophic and in the course of endo-exotrophic period, and its cytoplasm contains numerous yolk inclusions. After yolk exhaustion the YSL is flat. As the YSL degrades, the YSN become pycnotic, and the YSL remnant probably is cleared by phagocytes. Copyright © 2013 Wiley Periodicals, Inc.

  2. Exploring cytoplasmic dynamics in zebrafish yolk cells by single particle tracking of fluorescent nanodiamonds

    NASA Astrophysics Data System (ADS)

    Chang, Cheng-Chun; Zhang, Bailin; Li, Che-Yu; Hsieh, Chih-Chien; Duclos, Guillaume; Treussart, François; Chang, Huan-Cheng

    2012-02-01

    Fluorescent nanodiamonds (FNDs) have recently developed into an exciting new tool for bioimaging applications. The material possesses several unique features including high biocompatibility, easy bioconjugation, and perfect photostability, making it a promising optical nanoprobe in vitro as well as in vivo. This work explores the potential application of this novel nanomaterial as a photostable, nontoxic tracer in vivo using zebrafish as a model organism. We introduced FNDs into the yolk of a zebrafish embryo by microinjection at the 1-cell stage. Movements of the injected particles were investigated by using single particle tracking techniques. We observed unidirectional and stop-and-go traffic as part of the intricate cytoplasmic movements in the yolk cell. We determined a velocity in the range of 0.19 - 0.40 μm/s for 40 particles moving along with the axial streaming in the early developmental stage (1 to 2 hours post fertilization) of the zebrafish embryos.

  3. Expression of thyroid hormone regulator genes in the yolk sac membrane of the developing chicken embryo

    PubMed Central

    TOO, Hanny Cho; SHIBATA, Mitsuhiro; YAYOTA, Masato; DARRAS, Veerle M.; IWASAWA, Atsushi

    2017-01-01

    Thyroid hormones (THs) are essential for the correct development of nearly every structure in the body from the very early stages of development, yet the embryonic thyroid gland is not functional at these stages. To clarify the roles of the egg yolk as a source of THs, the TH content in the yolk and the expression of TH regulator genes in the yolk sac membrane were evaluated throughout the 21-day incubation period of chicken embryos. The yolk TH content (22.3 ng triiodothyronine and 654.7 ng thyroxine per total yolk on day 4 of incubation) decreased almost linearly along with development. Real-time PCR revealed gene expression of transthyretin, a principal TH distributor in the chicken, and of a TH-inactivating iodothyronine deiodinase (DIO3), until the second week of incubation when the embryonic pituitary-thyroid axis is generally thought to start functioning. The TH-activating deiodinase (DIO2) and transmembrane transporter of thyroxine (SLCO1C1) genes were expressed in the last week of incubation, which coincided with a marked increase of circulating thyroxine and a reduction in the yolk sac weight. DIO1, which can remove iodine from inactive THs, was expressed throughout the incubation period. It is assumed that the chicken yolk sac inactivates THs contained abundantly in the yolk and supplies the hormones to the developing embryo in appropriate concentrations until the second week of incubation, while THs may be activated in the yolk sac membrane in the last week of incubation. Additionally, the yolk sac could serve as a source of iodine for the embryo. PMID:28652559

  4. ApoA-II directs morphogenetic movements of zebrafish embryo by preventing chromosome fusion during nuclear division in yolk syncytial layer.

    PubMed

    Zhang, Ting; Yao, Shaohua; Wang, Ping; Yin, Chaoran; Xiao, Chun; Qian, Meilin; Liu, Donghui; Zheng, Lemin; Meng, Wentong; Zhu, Hongyan; Liu, Jin; Xu, Hong; Mo, Xianming

    2011-03-18

    The high density lipoprotein (HDL) represents a class of lipid- and protein-containing particles and consists of two major apolipoproteins apoA-I and apoA-II. ApoA-II has been shown to be involved in the pathogenesis of insulin resistance, adiposity, diabetes, and metabolic syndrome. In embryo, apoa2 mRNAs are abundant in the liver, brain, lung, placenta, and in fish yolk syncytial layer (YSL), suggesting that apoa2 may perform a function during embryonic development. Here we find out that apoa2 modulates zebrafish embryonic development by regulating the organization of YSL. Disruption of apoa2 function in zebrafish caused chromosome fusing, which strongly blocked YSL nuclear division, inducing disorders in YSL organization and finally disturbing the embryonic epiboly. Purified native human apoA-II was able specifically to rescue the defects and induced nuclear division in zebrafish embryos and in human HeLa cells. The C terminus of apoA-II was required for the proper chromosome separation during nuclear division of YSL in zebrafish embryos and in human HeLa cells. Our data indicate that organization of YSL is required for blastoderm patterning and morphogenesis and suggest that apolipoprotein apoA-II is a novel factor of nuclear division in YSL involved in the regulation of early zebrafish embryonic morphogenesis and in mammalian cells for proliferation.

  5. ApoA-II Directs Morphogenetic Movements of Zebrafish Embryo by Preventing Chromosome Fusion during Nuclear Division in Yolk Syncytial Layer*

    PubMed Central

    Zhang, Ting; Yao, Shaohua; Wang, Ping; Yin, Chaoran; Xiao, Chun; Qian, Meilin; Liu, Donghui; Zheng, Lemin; Meng, Wentong; Zhu, Hongyan; Liu, Jin; Xu, Hong; Mo, Xianming

    2011-01-01

    The high density lipoprotein (HDL) represents a class of lipid- and protein-containing particles and consists of two major apolipoproteins apoA-I and apoA-II. ApoA-II has been shown to be involved in the pathogenesis of insulin resistance, adiposity, diabetes, and metabolic syndrome. In embryo, apoa2 mRNAs are abundant in the liver, brain, lung, placenta, and in fish yolk syncytial layer (YSL), suggesting that apoa2 may perform a function during embryonic development. Here we find out that apoa2 modulates zebrafish embryonic development by regulating the organization of YSL. Disruption of apoa2 function in zebrafish caused chromosome fusing, which strongly blocked YSL nuclear division, inducing disorders in YSL organization and finally disturbing the embryonic epiboly. Purified native human apoA-II was able specifically to rescue the defects and induced nuclear division in zebrafish embryos and in human HeLa cells. The C terminus of apoA-II was required for the proper chromosome separation during nuclear division of YSL in zebrafish embryos and in human HeLa cells. Our data indicate that organization of YSL is required for blastoderm patterning and morphogenesis and suggest that apolipoprotein apoA-II is a novel factor of nuclear division in YSL involved in the regulation of early zebrafish embryonic morphogenesis and in mammalian cells for proliferation. PMID:21212265

  6. Multiplication of Salmonella Enteritidis in egg yolks after inoculation outside, on, and inside vitelline membranes and storage at different temperatures

    Prompt refrigeration to restrict bacterial growth is important for reducing egg-borne transmission of Salmonella enterica serovar Enteritidis (SE). The nutrient-rich yolk interior is a relatively infrequent location for initial SE deposition in eggs, but migration across the vitelline membrane can ...

  7. Effect of egg weight on composition, embryonic growth, and expression of amino acid transporter genes in yolk sac membranes and small intestines of the domestic pigeon (Columba livia).

    PubMed

    Chen, M X; Li, X G; Yan, H C; Wang, X Q; Gao, C Q

    2016-06-01

    The objective of this study was to investigate the effect of egg weight on the composition of the egg, the growth of the embryo, and the expression of amino acid transporter genes in the yolk sac membranes and small intestines of the domestic pigeon (Columba livia). A total of 240 fertilized eggs were collected and divided into two groups based on the weight of the eggs, light (LE) and heavy (HE). The composition of 20 eggs from each group was measured, and the remaining eggs were weighed and placed in an incubator. On embryonic days (E) 9, 11, 13, and 15 and day of hatch (DOH), 15 embryos/hatchlings from each group were measured for embryonic growth, and samples were collected. The HE had heavier yolk and albumen weights than the LE (P < 0.01). Compared with the LE, the HE had heavier yolk-free embryonic body and yolk sac weights from E13 to DOH (P < 0.05). Additionally, the HE had larger yolk sac membrane weights from E13 to E15 (P < 0.05) and had more residual yolk sac content on DOH than those of the LE (P < 0.01). The yolk absorption was greater for the HE than for the LE from E11 to E13 (P < 0.05). Furthermore, the abundance of CAT2 and PepT1 mRNA in the yolk sac membranes was greater in the HE than in the LE on E13 (P < 0.05). Compared with the LE, the gene expression of EAAT2 in the intestine on E13 was greater in the HE, whereas the expression of EAAT3 was lower in the HE (P < 0.05). Taken together, our results suggest that egg weight influenced the composition of the eggs, embryonic development, and expression of amino acid transporter genes in the yolk sac membranes and small intestines of pigeon embryos. © 2016 Poultry Science Association Inc.

  8. Zebrafish collagen XII is present in embryonic connective tissue sheaths (fascia) and basement membranes.

    PubMed

    Bader, Hannah L; Keene, Douglas R; Charvet, Benjamin; Veit, Guido; Driever, Wolfgang; Koch, Manuel; Ruggiero, Florence

    2009-01-01

    Connective tissues ensure the cohesion of the tissues of the body, but also form specialized structures such as tendon and bone. Collagen XII may enhance the stability of connective tissues by bridging collagen fibrils, but its function is still unclear. Here, we used the zebrafish model to visualize its expression pattern in the whole organism. The zebrafish col12a1 gene is homologous to the small isoform of the tetrapod col12a1 gene. In agreement with the biochemical data reported for the small isoform, the zebrafish collagen XII alpha1 chain was characterized as a collagenase sensitive band migrating at approximately 200 kDa. Using newly generated polyclonal antibodies and anti-sense probes, we performed a comprehensive analysis of its expression in developing zebrafish. Collagen XII exhibited a much broader expression pattern than previously thought: it was ubiquitously expressed in the connective tissue sheaths (fascia) that encase the tissues and organs of the body. For example, it was found in sclera, meninges, epimysia and horizontal and vertical myosepta. Collagen XII was also detected in head mesenchyme, pharyngeal arches and within the spinal cord, where it was first expressed within and then at the lateral borders of the floor plate and at the dorsal midline. Furthermore, double immunofluorescence staining with laminin and immunogold electron microscopy revealed that collagen XII is associated with basement membranes. These data suggest that collagen XII is implicated in tissue cohesion by stabilizing fascia and by linking fascia to basement membranes.

  9. Embryo yolk sac membrane kynurenine formamidase of l-tryptophan to NAD+ pathway as a primary target for organophosphorus insecticides (OPI) in OPI-induced NAD-associated avian teratogenesis.

    PubMed

    Seifert, Josef

    2017-10-01

    The objective of this study was to provide in ovo evidence for the proposed role of kynurenine formamidase of l-tryptophan to NAD + pathway in embryo yolk sac membranes as a primary target for organophosphorus insecticide (OPI) teratogens in OPI-induced NAD-associated avian teratogenesis. Slices prepared from yolk sac membranes or embryo livers of chicken eggs treated with the OPI dicrotophos and/or methyl parathion were incubated with l-tryptophan. Yolk sac membrane slices metabolized l-tryptophan in the pathway to NAD + before that function was established in livers. OPI interfered in ovo with the second step of l-tryptophan to NAD + biosynthesis by inhibiting kynurenine formamidase. Its inhibition due to the teratogen dicrotophos occurred in yolk sac membranes during the period of embryo highest susceptibility to OPI teratogens in contrast to delayed and lower inhibition caused by the nonteratogen methyl parathion. Both OPI affected liver kynurenine formamidase in a similar manner. The onsets of liver enzyme inhibition, however, were delayed by about two days and occurred at the time of the reduced embryo susceptibility to teratogens. The early disruption of l-tryptophan metabolism and higher inhibition of kynurenine formamidase in yolk sac membranes may be the factors that determine action of OPI as teratogens in chicken embryos. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. The zebrafish dystrophic mutant softy maintains muscle fibre viability despite basement membrane rupture and muscle detachment

    PubMed Central

    Jacoby, Arie S.; Busch-Nentwich, Elisabeth; Bryson-Richardson, Robert J.; Hall, Thomas E.; Berger, Joachim; Berger, Silke; Sonntag, Carmen; Sachs, Caroline; Geisler, Robert; Stemple, Derek L.; Currie, Peter D.

    2009-01-01

    Summary The skeletal muscle basement membrane fulfils several crucial functions during development and in the mature myotome and defects in its composition underlie certain forms of muscular dystrophy. A major component of this extracellular structure is the laminin polymer, which assembles into a resilient meshwork that protects the sarcolemma during contraction. Here we describe a zebrafish mutant, softy, which displays severe embryonic muscle degeneration as a result of initial basement membrane failure. The softy phenotype is caused by a mutation in the lamb2 gene, identifying laminin β2 as an essential component of this basement membrane. Uniquely, softy homozygotes are able to recover and survive to adulthood despite the loss of myofibre adhesion. We identify the formation of ectopic, stable basement membrane attachments as a novel means by which detached fibres are able to maintain viability. This demonstration of a muscular dystrophy model possessing innate fibre viability following muscle detachment suggests basement membrane augmentation as a therapeutic strategy to inhibit myofibre loss. PMID:19736328

  11. Functional genomics in zebrafish permits rapid characterization of novel platelet membrane proteins.

    PubMed

    O'Connor, Marie N; Salles, Isabelle I; Cvejic, Ana; Watkins, Nicholas A; Walker, Adam; Garner, Stephen F; Jones, Chris I; Macaulay, Iain C; Steward, Michael; Zwaginga, Jaap-Jan; Bray, Sarah L; Dudbridge, Frank; de Bono, Bernard; Goodall, Alison H; Deckmyn, Hans; Stemple, Derek L; Ouwehand, Willem H

    2009-05-07

    In this study, we demonstrate the suitability of the vertebrate Danio rerio (zebrafish) for functional screening of novel platelet genes in vivo by reverse genetics. Comparative transcript analysis of platelets and their precursor cell, the megakaryocyte, together with nucleated blood cell elements, endothelial cells, and erythroblasts, identified novel platelet membrane proteins with hitherto unknown roles in thrombus formation. We determined the phenotype induced by antisense morpholino oligonucleotide (MO)-based knockdown of 5 of these genes in a laser-induced arterial thrombosis model. To validate the model, the genes for platelet glycoprotein (GP) IIb and the coagulation protein factor VIII were targeted. MO-injected fish showed normal thrombus initiation but severely impaired thrombus growth, consistent with the mouse knockout phenotypes, and concomitant knockdown of both resulted in spontaneous bleeding. Knockdown of 4 of the 5 novel platelet proteins altered arterial thrombosis, as demonstrated by modified kinetics of thrombus initiation and/or development. We identified a putative role for BAMBI and LRRC32 in promotion and DCBLD2 and ESAM in inhibition of thrombus formation. We conclude that phenotypic analysis of MO-injected zebrafish is a fast and powerful method for initial screening of novel platelet proteins for function in thrombosis.

  12. Functional genomics in zebrafish permits rapid characterization of novel platelet membrane proteins

    PubMed Central

    O'Connor, Marie N.; Salles, Isabelle I.; Cvejic, Ana; Watkins, Nicholas A.; Walker, Adam; Garner, Stephen F.; Jones, Chris I.; Macaulay, Iain C.; Steward, Michael; Zwaginga, Jaap-Jan; Bray, Sarah L.; Dudbridge, Frank; de Bono, Bernard; Goodall, Alison H.; Stemple, Derek L.; Ouwehand, Willem H.

    2009-01-01

    In this study, we demonstrate the suitability of the vertebrate Danio rerio (zebrafish) for functional screening of novel platelet genes in vivo by reverse genetics. Comparative transcript analysis of platelets and their precursor cell, the megakaryocyte, together with nucleated blood cell elements, endothelial cells, and erythroblasts, identified novel platelet membrane proteins with hitherto unknown roles in thrombus formation. We determined the phenotype induced by antisense morpholino oligonucleotide (MO)–based knockdown of 5 of these genes in a laser-induced arterial thrombosis model. To validate the model, the genes for platelet glycoprotein (GP) IIb and the coagulation protein factor VIII were targeted. MO-injected fish showed normal thrombus initiation but severely impaired thrombus growth, consistent with the mouse knockout phenotypes, and concomitant knockdown of both resulted in spontaneous bleeding. Knockdown of 4 of the 5 novel platelet proteins altered arterial thrombosis, as demonstrated by modified kinetics of thrombus initiation and/or development. We identified a putative role for BAMBI and LRRC32 in promotion and DCBLD2 and ESAM in inhibition of thrombus formation. We conclude that phenotypic analysis of MO-injected zebrafish is a fast and powerful method for initial screening of novel platelet proteins for function in thrombosis. PMID:19109564

  13. Endoscopy, histology and electron microscopy analysis of foetal membranes in pregnant South American plains vizcacha reveal unusual excrescences on the yolk sac.

    PubMed

    Giacchino, Mariela; Inserra, Pablo I F; Lange, Fernando D; Gariboldi, María C; Ferraris, Sergio R; Vitullo, Alfredo D

    2018-06-01

    The South American hystricognathe Lagostomus maximus is a fossorial rodent whose females show unique reproductive characteristics. They have a 155-day long gestation, show massive polyovulation and a selective process of embryonic resorption in the first half of gestation. In order to explore and perform an in-situ characterization of the reproductive tract, we visualized internal structures through ultrasonography and video-endoscopy in pregnant and non-pregnant females. We describe the finding of protruding structures that lie on the yolk sac and their histological and ultrastructural characterization. The placenta was covered with whitish, small pearl-shaped structures. These structures were also seen on the extra-embryonic space, being the amnion and the umbilical cord free of them. Pearl-shaped structures were composed with loose connective tissue, lacked blood vessels, and showed collagen fibers organized in a spiral form. They were anchored by pedicles to the villous surface of the extraembryonic membrane. We discuss the biological and evolutionary meaning of the pearl-shaped structures that relate L. maximus to the African origin of the South American hystricognathe fauna.

  14. Myomaker mediates fusion of fast myocytes in zebrafish embryos

    SciT

    Landemaine, Aurélie; Rescan, Pierre-Yves; Gabillard, Jean-Charles, E-mail: Jean-charles.gabillard@rennes.inra.fr

    2014-09-05

    Highlights: • Myomaker is transiently expressed in fast myocytes during embryonic myogenesis. • Myomaker is essential for fast myocyte fusion in zebrafish. • The function of myomaker is conserved among Teleostomi. - Abstract: Myomaker (also called Tmem8c), a new membrane activator of myocyte fusion was recently discovered in mice. Using whole mount in situ hybridization on zebrafish embryos at different stages of embryonic development, we show that myomaker is transiently expressed in fast myocytes forming the bulk of zebrafish myotome. Zebrafish embryos injected with morpholino targeted against myomaker were alive after yolk resorption and appeared morphologically normal, but they weremore » unable to swim, even under effect of a tactile stimulation. Confocal observations showed a marked phenotype characterized by the persistence of mononucleated muscle cells in the fast myotome at developmental stages where these cells normally fuse to form multinucleated myotubes. This indicates that myomaker is essential for myocyte fusion in zebrafish. Thus, there is an evolutionary conservation of myomaker expression and function among Teleostomi.« less

  15. The hyaloid vasculature facilitates basement membrane breakdown during choroid fissure closure in the zebrafish eye.

    PubMed

    James, Andrea; Lee, Chanjae; Williams, Andre M; Angileri, Krista; Lathrop, Kira L; Gross, Jeffrey M

    2016-11-15

    A critical aspect of vertebrate eye development is closure of the choroid fissure (CF). Defects in CF closure result in colobomas, which are a significant cause of childhood blindness worldwide. Despite the growing number of mutated loci associated with colobomas, we have a limited understanding of the cell biological underpinnings of CF closure. Here, we utilize the zebrafish embryo to identify key phases of CF closure and regulators of the process. Utilizing Laminin-111 as a marker for the basement membrane (BM) lining the CF, we determine the spatial and temporal patterns of BM breakdown in the CF, a prerequisite for CF closure. Similarly, utilizing a combination of in vivo time-lapse imaging, β-catenin immunohistochemistry and F-actin staining, we determine that tissue fusion, which serves to close the fissure, follows BM breakdown closely. Periocular mesenchyme (POM)-derived endothelial cells, which migrate through the CF to give rise to the hyaloid vasculature, possess distinct actin foci that correlate with regions of BM breakdown. Disruption of talin1, which encodes a regulator of the actin cytoskeleton, results in colobomas and these correlate with structural defects in the hyaloid vasculature and defects in BM breakdown. cloche mutants, which entirely lack a hyaloid vasculature, also possess defects in BM breakdown in the CF. Taken together, these data support a model in which the hyaloid vasculature and/or the POM-derived endothelial cells that give rise to the hyaloid vasculature contribute to BM breakdown during CF closure. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Distributional shift of urea production site from the extraembryonic yolk sac membrane to the embryonic liver during the development of cloudy catshark (Scyliorhinus torazame).

    PubMed

    Takagi, Wataru; Kajimura, Makiko; Tanaka, Hironori; Hasegawa, Kumi; Ogawa, Shuntaro; Hyodo, Susumu

    2017-09-01

    Urea is an essential osmolyte for marine cartilaginous fishes. Adult elasmobranchs and holocephalans are known to actively produce urea in the liver, muscle and other extrahepatic organs; however, osmoregulatory mechanisms in the developing cartilaginous fish embryo with an undeveloped urea-producing organ are poorly understood. We recently described the contribution of extraembryonic yolk sac membranes (YSM) to embryonic urea synthesis during the early developmental period of the oviparous holocephalan elephant fish (Callorhinchus milii). In the present study, to test whether urea production in the YSM is a general phenomenon among oviparous Chondrichthyes, we investigated gene expression and activities of ornithine urea cycle (OUC) enzymes together with urea concentrations in embryos of the elasmobranch cloudy catshark (Scyliorhinus torazame). The intracapsular fluid, in which the catshark embryo develops, had a similar osmolality to seawater, and embryos maintained a high concentration of urea at levels similar to that of adult plasma throughout development. Relative mRNA expressions and activities of catshark OUC enzymes were significantly higher in YSM than in embryos until stage 32. Concomitant with the development of the embryonic liver, the expression levels and activities of OUC enzymes were markedly increased in the embryo from stage 33, while those of the YSM decreased from stage 32. The present study provides further evidence that the YSM contributes to embryonic urea homeostasis until the liver and other extrahepatic organs become fully functional, and that urea-producing tissue shifts from the YSM to the embryonic liver in the late developmental period of oviparous marine cartilaginous fishes. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. 21 CFR 160.180 - Egg yolks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Egg yolks. 160.180 Section 160.180 Food and Drugs... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.180 Egg yolks. (a) Egg yolks, liquid egg yolks, yolks, liquid yolks are yolks of eggs of the domestic hen so...

  18. 21 CFR 160.180 - Egg yolks.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Egg yolks. 160.180 Section 160.180 Food and Drugs... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.180 Egg yolks. (a) Egg yolks, liquid egg yolks, yolks, liquid yolks are yolks of eggs of the domestic hen so...

  19. Involvement of estradiol-17beta and its membrane receptor, G protein coupled receptor 30 (GPR30) in regulation of oocyte maturation in zebrafish, Danio rario.

    PubMed

    Pang, Yefei; Thomas, Peter

    2009-03-01

    The orphan G protein coupled receptor, GPR30, has the characteristics of a high affinity, specific estrogen membrane receptor on Atlantic croaker oocytes and mediates estrogen inhibition of oocyte maturation in this perciform fish. In order to determine the broad applicability of these findings to other teleosts, similar experiments were conducted in a cyprinid fish, zebrafish, in the present study. GPR30 mRNA expression was detected in zebrafish oocytes but not in the ovarian follicular cells. Both spontaneous and 17, 20beta-dihyroxy-4-pregnen-3-one (DHP)-induced maturation of follicle-enclosed zebrafish oocytes was significantly decreased when they were incubated with either estradiol-17beta, or the GPR30 agonists, ICI 182 780 and tamoxifen, or with the GPR30 specific agonist G-1. On the other hand spontaneous oocyte maturation increased two-fold when zebrafish ovarian follicles were incubated with an aromatase inhibitor, ATD. Moreover, the stimulatory effects of ATD on germinal vesicle breakdown (GVBD) were partially reversed by co-treatment with 100 nM of E2 or G-1. These results suggest that endogenous estrogens acting through GPR30 are involved in maintaining meiotic arrest of zebrafish oocytes.

  20. Evaluation in zebrafish model of the toxicity of rhodamine B-conjugated crotamine, a peptide potentially useful for diagnostics and therapeutics.

    PubMed

    Chan, Judy Yuet-Wa; Zhou, Hefeng; Kwan, Yiu Wa; Chan, Shun Wan; Radis-Baptista, Gandhi; Lee, Simon Ming-Yuen

    2017-11-01

    Crotamine is defensin-like cationic peptide from rattlesnake venom that possesses anticancer, antimicrobial, and antifungal properties. Despite these promising biological activities, toxicity is a major concern associated with the development of venom-derived peptides as therapeutic agents. In the present study, we used zebrafish as a system model to evaluate the toxicity of rhodamine B-conjugated (RhoB) crotamine derivative. The lethal toxic concentration of RhoB-crotamine was as low as 4 μM, which effectively kill zebrafish larvae in less than 10 min. With non-lethal concentrations (<1 μM), crotamine caused malformation in zebrafish embryos, delayed or completely halted hatching, adversely affected embryonic developmental programming, decreased the cardiac functions, and attenuated the swimming distance of zebrafish. The RhoB-crotamine translocated across vitelline membrane and accumulated in zebrafish yolk sac. These results demonstrate the sensitive responsivity of zebrafish to trial crotamine analogues for the development of novel therapeutic peptides with improved safety, bioavailability, and efficacy profiles. © 2017 Wiley Periodicals, Inc.

  1. Morphologic analysis of the zebrafish digestive system.

    PubMed

    Trotter, Andrew J; Parslow, Adam C; Heath, Joan K

    2009-01-01

    The zebrafish provides an ideal model for the study of vertebrate organogenesis, including the formation of the digestive tract and its associated organs. Despite optical transparency of embryos, the internal position of the developing digestive system and its close juxtaposition with the yolk initially made morphological analysis relatively challenging, particularly during the first 3 d of development. However, methodologies have been successfully developed to address these problems and comprehensive morphologic analysis of the developing digestive system has now been achieved using a combination of light and fluorescence microscope approaches-including confocal analysis-to visualize wholemount and histological preparations of zebrafish embryos. Furthermore, the expanding number of antibodies that cross-react with zebrafish proteins and the generation of tissue-specific transgenic green fluorescent protein reporter lines that mark specific cell and tissue compartments have greatly enhanced our ability to successfully image the developing zebrafish digestive system.

  2. Phototoxicity of TiO2 nanoparticles to zebrafish (Danio rerio) is dependent on life stage.

    PubMed

    Ma, Hongbo; Diamond, Stephen A

    2013-09-01

    Zebrafish embryos have been used increasingly to evaluate nanomaterial toxicity. The present study compared phototoxicity of TiO2 nanoparticles with zebrafish at 4 life stages (embryos, yolk-sac larvae, free-swimming larvae, and juvenile) under simulated sunlight using the 96-h standard toxicity assay. Yolk-sac larvae were found to be the most sensitive to TiO2 phototoxicity, suggesting that the widely used zebrafish embryo test may not fully or accurately predict hazard and risk of these nanoparticles to small fish. Copyright © 2013 SETAC.

  3. Curcumin affects development of zebrafish embryo.

    PubMed

    Wu, Jheng-Yu; Lin, Chin-Yi; Lin, Tien-Wei; Ken, Chuian-Fu; Wen, Yu-Der

    2007-07-01

    Embryotoxic and teratogenic effects of curcumin on the development of zebrafish embryo were investi-gated in this study. The LD(50) values of curcumin (24-h incubation) were estimated at 7.5 microM and 5 microM for embryos and larvae, respectively. The developmental defects caused by curcumin treatments include bent or hook-like tails, spinal column curving, edema in pericardial sac, retarded yolk sac resorption, and shorter body length. In curcumin-treated larvae, fluorescence signals of curcumin were found in edamae sac and some skin cells. Together, these results indicate that zebrafish are suitable model organisms to study the toxic effects of curcumin.

  4. Myosin-1 inhibition by PClP affects membrane shape, cortical actin distribution and lipid droplet dynamics in early Zebrafish embryos

    PubMed Central

    Gupta, Prabuddha; Martin, René; Knölker, Hans-Joachim; Nihalani, Deepak; Kumar Sinha, Deepak

    2017-01-01

    Myosin-1 (Myo1) represents a mechanical link between the membrane and actin-cytoskeleton in animal cells. We have studied the effect of Myo1 inhibitor PClP in 1–8 cell Zebrafish embryos. Our results indicate a unique involvement of Myo1 in early development of Zebrafish embryos. Inhibition of Myo1 (by PClP) and Myo2 (by Blebbistatin) lead to arrest in cell division. While Myo1 isoforms appears to be important for both the formation and the maintenance of cleavage furrows, Myo2 is required only for the formation of furrows. We found that the blastodisc of the embryo, which contains a thick actin cortex (~13 μm), is loaded with cortical Myo1. Myo1 appears to be crucial for maintaining the blastodisc morphology and the actin cortex thickness. In addition to cell division and furrow formation, inhibition of Myo1 has a drastic effect on the dynamics and distribution of lipid droplets (LDs) in the blastodisc near the cleavage furrow. All these results above are effects of Myo1 inhibition exclusively; Myo2 inhibition by blebbistatin does not show such phenotypes. Therefore, our results demonstrate a potential role for Myo1 in the maintenance and formation of furrow, blastodisc morphology, cell-division and LD organization within the blastodisc during early embryogenesis. PMID:28678859

  5. Zebrafish Dkk3a Protein Regulates the Activity of myf5 Promoter through Interaction with Membrane Receptor Integrin α6b*

    PubMed Central

    Fu, Chuan-Yang; Su, Ying-Fang; Lee, Ming-Hsuan; Chang, Geen-Dong; Tsai, Huai-Jen

    2012-01-01

    Myogenic regulatory factor Myf5 plays important roles in muscle development. In zebrafish myf5, a microRNA (miR), termed miR-3906 or miR-In300, was reported to silence dickkopf-3-related gene (dkk3r or dkk3a), resulting in repression of myf5 promoter activity. However, the membrane receptor that interacts with ligand Dkk3a to control myf5 expression through signal transduction remains unknown. To address this question, we applied immunoprecipitation and LC-MS/MS to screen putative membrane receptors of Dkk3a, and Integrin α6b (Itgα6b) was finally identified. To further confirm this, we used cell surface binding assays, which showed that Dkk3a and Itgα6b were co-expressed at the cell membrane of HEK-293T cells. Cross-linking immunoprecipitation data also showed high affinity of Itgα6b for Dkk3a. We further proved that the β-propeller repeat domains of Itgα6b are key segments bound by Dkk3a. Moreover, when dkk3a and itgα6b mRNAs were co-injected into embryos, luciferase activity was up-regulated 4-fold greater than that of control embryos. In contrast, the luciferase activities of dkk3a knockdown embryos co-injected with itgα6b mRNA and itgα6b knockdown embryos co-injected with dkk3a mRNA were decreased in a manner similar to that in control embryos, respectively. Knockdown of itgα6b resulted in abnormal somite shape, fewer somitic cells, weaker or absent myf5 expression, and reduced the protein level of phosphorylated p38a in somites. These defective phenotypes of trunk muscular development were similar to those of dkk3a knockdown embryos. We demonstrated that the secreted ligand Dkk3a binds to the membrane receptor Itgα6b, which increases the protein level of phosphorylated p38a and activates myf5 promoter activity of zebrafish embryos during myogenesis. PMID:23024366

  6. The Zebrafish G12 Gene is required for Nuclear Positioning and Cell Migrations during Early Development

    NASA Technical Reports Server (NTRS)

    Reinsch, S. S.; Conway, G. C.

    2003-01-01

    After fertilization Zebrafish embryos undergo synchronous cleavage to form a blastula of cells sitting upon a single multinucleate yolk cell. At the beginning of gastrulation these cells undergo extensive cell migrations to form the major body axes. We have discovered a gene, G12, which is required for cell migrations and positioning of nuclei in the large syncytial yolk cell. Overexpression of a G12-GFP fusion protein is not toxic and shows that the protein localizes inside the yolk cell to the yolk nuclei, microtubules, and to the margin between the blastomeres and the large yolk cell. Morpholino (MO) injection into the 1-cell embryo or into just the yolk syncytium conipletely inhibits cell migrations, doming of the yolk cell, and positioning of nuclei around the margin. This effect can be partially rescued by injection of G12-GFP encoding RNA. Given the known role of microtubules in nuclear positioning of yolk nuclei in Zebrafish, we investigated the microtubules in morpholiiio injected and rescued embryos. We find that microtubules are sparse and disorganized in MO-injected embryos and are restored to normal organization upon G12-GFP rescue. G12 plays a pivotal role in organization of inicrotubules during early development. G12 is highly conserved in vertebrates and two homologues exist in the human genome. One of the human hoinologues is amplified in aggressive breast tumors.

  7. Transfer of Vitamins E and A from yolk to embryo during development of the king penguin (Aptenodytes patagonicus).

    PubMed

    Surai, P F; Speake, B K; Decrock, F; Groscolas, R

    2001-01-01

    Since the yolk lipids of the king penguin (Aptenodytes patagonicus) are rich in n-3 fatty acids, which are potentially susceptible to peroxidative damage, the yolk contents and yolk-to-embryo transfer of antioxidants and lipid-soluble vitamins were investigated under conditions of natural incubation in the wild. The concentration of vitamin E in the unincubated egg was 155 microg/g wet yolk, of which 88% was alpha-tocopherol and the rest was gamma-tocopherol. Vitamin A (2.9 microg/g) was present in the yolk entirely as retinol; no retinyl esters were detected. Throughout the latter half of the incubation period, vitamins E and A were taken up from the yolk into the yolk sac membrane (YSM) and later accumulated in the liver, with vitamin A being transferred in advance of vitamin E. In the YSM, vitamin A was present almost entirely as retinyl ester, indicating that the free retinol of the yolk is rapidly esterified following uptake. Retinyl esters were also the predominant form in the liver. The retinyl esters of the liver and YSM displayed different fatty acid profiles. At hatching, the brain contained relatively little vitamin E (4.7 microg/g) compared to the much higher concentration in the liver (482.9 microg/g) at this stage. Ascorbic acid was not detected in the yolk but was present at a high concentration in the brain at day 27 (404.6 microg/g), decreasing to less than half this value by the time of hatching. This report is the first to delineate the yolk-to-embryo transfer of lipid-soluble vitamins for a free-living avian species. The yolk fatty acids of the king penguin provide an extreme example of potential oxidative susceptibility, forming a basis for comparative studies on embryonic antioxidant requirements among species of birds whose yolk lipids differ in their degree of unsaturation.

  8. 21 CFR 160.185 - Dried egg yolks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Dried egg yolks. 160.185 Section 160.185 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.185 Dried egg yolks. (a) Dried egg yolks, dried yolks is the food prepared by drying egg yolks that conform to...

  9. 21 CFR 160.190 - Frozen egg yolks.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks that...

  10. 21 CFR 160.190 - Frozen egg yolks.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen egg yolks. 160.190 Section 160.190 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.190 Frozen egg yolks. (a) Frozen egg yolks, frozen yolks is the food prepared by freezing egg yolks that...

  11. Yolk formation in some Charadriiform birds

    Roudybush, T.E.; Grau, C.R.; Petersen, M.R.; Ainley, D.G.; Hirsch, K.V.; Gilman, A.P.; Patten, S.M.

    1979-01-01

    By counting and measuring the major ova of breeding birds at autopsy and combining these data with time intervals between ovipositions, rough estimates have been made of the time required to form yolk in some non-captive birds (King 1973). Direct studies have been made in domestic fowl (Gallus gallus var. domesticus; Gilbert 1972), turkeys (Meleagris galloparvo; Bacon and Cherms 1968), and Common quail (Coturnix coturnix; Bacon and Koontz 1971), by feeding the birds a capsule containing dye each day, and counting dye rings in the yolks after the eggs have been hardcooked. Recently developed methods of fixing and staining eggs have revealed differences in yolk deposited during day and night, thus permitting another estimation of the number of days during which yolk was deposited, and without direct contact with the female (Grau 1976). In eggs from chickens and quail that have been fed dyes, yolk that stained darkly with dichromate was shown to be deposited during the active daytime feeding periods, while pale-staining yolk was deposited during the night. Thus, pairs of light and dark rings, which together take a day to be deposited, may be counted to estimate time of yolk formation.In the present study we have applied the yolk ring method of estimating the number of days during which the bulk of the yolk is deposited around the central white core (Grau 1976) to the eggs of some shorebirds, gulls, terns and alcids.

  12. Zebrafish Melanoma.

    PubMed

    Kaufman, Charles K

    2016-01-01

    Melanoma skin cancer is a potentially deadly disease in humans and has remained extremely difficult to treat once it has metastasized. In just the last 10 years, a number of models of melanoma have been developed in the zebrafish that are biologically faithful to the human disease and have already yielded important insights into the fundamental biology of melanoma and offered new potential avenues for treatment. With the diversity and breadth of the molecular genetic tools available in the zebrafish, these melanoma models will continue to be refined and expanded upon to keep pace with the rapidly evolving field of melanoma biology.

  13. Effects of DHA-enriched hen egg yolk and L-cysteine supplementation on quality of cryopreserved boar semen.

    PubMed

    Chanapiwat, Panida; Kaeoket, Kampon; Tummaruk, Padet

    2009-09-01

    The objective of the present study was to determine the effects of docosahexaenoic acid (DHA)-enriched hen egg yolks and L-cysteine supplementation on the qualities of the cryopreserved boar semen. A total of 15 ejaculates from 5 Pietrain boars were divided into 4 groups according to the compositions of the freezing extenders used, that is, normal hen egg yolk (group I), DHA-enriched hen egg yolk (group II), normal hen egg yolk with 5 mmol L(-1) of cysteine supplementation (group III) and DHA-enriched hen egg yolk with 5 mmol L(-1) of cysteine supplementation (group IV). The semen was cryopreserved using controlled rate freezer and was thawed at 50 degrees C for 12 s. Progressive motility, sperm viability, acrosome integrity and functional integrity of sperm plasma membrane of the post-thawed semen were evaluated. The supplementation of L-cysteine in the freezing extender alone (group III) improved progressive motility (P < 0.05), and the supplementation of L-cysteine in combination with DHA-enriched hen egg yolk (group IV) improved both progressive motility (P < 0.05) and acrosome integrity (P < 0.01). The use of DHA-enriched hen egg yolk alone (group II) did not enhance any of the post-thawed semen qualities (P > 0.05). In conclusion, the supplementation of antioxidant L-cysteine alone or in combination with DHA-enriched hen egg yolk significantly improved the post-thawed semen qualities, especially progressive motility and acrosome integrity.

  14. Rapid quantification of neutral lipids and triglycerides during zebrafish embryogenesis.

    PubMed

    Yoganantharjah, Prusothman; Byreddy, Avinesh R; Fraher, Daniel; Puri, Munish; Gibert, Yann

    2017-01-01

    The zebrafish is a useful vertebrate model to study lipid metabolism. Oil Red-O (ORO) staining of zebrafish embryos, though sufficient for visualizing the localization of triglycerides, was previously inadequate to quantify neutral lipid abundance. For metabolic studies, it is crucial to be able to quantify lipids during embryogenesis. Currently no cost effective, rapid and reliable method exists to quantify the deposition of neutral lipids and triglycerides. Thin layer chromatography (TLC), gas chromatography and mass spectrometry can be used to accurately measure lipid levels, but are time consuming and costly in their use. Hence, we developed a rapid and reliable method to quantify neutral lipids and triglycerides. Zebrafish embryos were exposed to Rimonabant (Rimo) or WIN 55,212-2 mesylate (WIN), compounds previously shown to modify lipid content during zebrafish embryogenesis. Following this, ORO stain was extracted out of both the zebrafish body and yolk sac and optical density was measured to give an indication of neutral lipid and triglyceride accumulation. Embryos treated with 0.3 microM WIN resulted in increased lipid accumulation, whereas 3 microM Rimo caused a decrease in lipid accumulation during embryogenesis. TLC was performed on zebrafish bodies to validate the developed method. In addition, BODIPY free fatty acids were injected into zebrafish embryos to confirm quantification of changes in lipid content in the embryo. Previously, ORO was limited to qualitative assessment; now ORO can be used as a quantitative tool to directly determine changes in the levels of neutral lipids and triglycerides.

  15. 21 CFR 160.180 - Egg yolks.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... destroy all viable Salmonella microorganisms. Pasteurization or such other treatment is deemed to permit... render the egg yolks free of viable Salmonella microorganisms, and that are not food additives as defined...

  16. 21 CFR 160.180 - Egg yolks.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... destroy all viable Salmonella microorganisms. Pasteurization or such other treatment is deemed to permit... render the egg yolks free of viable Salmonella microorganisms, and that are not food additives as defined...

  17. Homochiral Asymmetric Triacylglycerol Isomers in Egg Yolk.

    PubMed

    Nagai, Toshiharu; Ishikawa, Keiko; Yoshinaga, Kazuaki; Yoshida, Akihiko; Beppu, Fumiaki; Gotoh, Naohiro

    2017-12-01

    The composition of triacylglycerol (TAG) positional isomer (-PI) and enantiomer (-E) in immature chicken egg yolk, mature chicken yolk, and chicken meat was examined. POO (consisting of one palmitic acid (P) and two oleic acids (Os)), PPO (consisting of two Ps and one O), and PPL (consisting of two Ps and one linoleic acid (L)) were treated as representative TAG molecular species in all the analytical samples because P, O, and L were the major fatty acids comprising egg and chicken meat. sn-POO (binding P at sn-1 position) was predominant in egg yolks, while sn-OOP and sn-OPO were present in chicken meat. This difference was ascribed to the different roles of these isomers as nutrients, because TAG in egg yolk is important for new born organisms and TAG in chicken meat is used for fat accumulation. The compositions of the TAG isomers in PPO and PPL in egg yolk were similar, and O and L did not bind at the sn-1 position. In contrast, all the isomers of PPO and PPL were found in chicken meat. These results imply that the TAG structure could be modified so that the nutrient requirement is fulfilled in egg yolk and chicken meat.

  18. Cryopreservation of bull semen: Evolution from egg yolk based to soybean based extenders.

    PubMed

    Layek, S S; Mohanty, T K; Kumaresan, A; Parks, J E

    2016-09-01

    Since the inception of bovine semen cryopreservation, egg yolk and milk based extenders have been used to protect sperm from the detrimental effects of cooling and freezing. In recent years, demand for alternatives to conventional commercial extenders has arisen as the risk of introducing exotic diseases through transporting egg yolk based products has been recognized. Egg yolk can also interfere with sperm evaluation and the presence of particulate material in the extender may reduce fertility. Soybeans contain lecithin, a phospholipid fraction that can substitute for high molecular weight lipoprotein and phospholipids from egg yolk and prevent or ameliorate damage to the sperm plasma membrane that occurs during extension, cooling, and cryopreservation. Soy lecithin based extenders have been evaluated for processing and freezing bovine semen, although extender from soybean milk has not been studied as extensively. Commercially available soy lecithin based extenders are used increasingly but remain under scrutiny and are not universally accepted. With these observations in mind, this review is intended to examine effects of conventional cryopreservation procedures, methods of assessment, and potential for developing soybean extract as an acceptable alternative to traditional egg yolk and milk based extenders for bull sperm cryopreservation. Copyright © 2016. Published by Elsevier B.V.

  19. Effects of egg and yolk weights on yolk antibody (IgY) production in laying chickens.

    PubMed

    Li, X; Nakano, T; Sunwoo, H H; Paek, B H; Chae, H S; Sim, J S

    1998-02-01

    Twenty 35-wk-old chickens, including 10 Single Comb White Leghorn (SCWL) and 10 Rhode Island Red (RIR) hens, were used to examine the effects of egg and yolk weights on egg yolk antibody (IgY) production in the two strains of chickens immunized with BSA. The SCWL chickens had a greater (P < 0.01) percentage hen-day production and greater egg and yolk weights than did the RIR chickens. However, the anti-BSA antibody activities determined by ELISA in the serum and the egg yolk were similar (P > 0.05) between the SCWL and RIR chickens. Similarities between the two strains of hens were also observed in protein and total IgY contents (expressed as the percentage of wet weight of yolk) and the percentage of BSA-specific antibody in the total IgY. It was concluded that both the SCWL and RIR chickens immunized with BSA can produce egg yolk IgY containing similar proportions of BSA-specific antibodies. Therefore, the egg yolk weight and the percentage hen-day production, both of which are greater in the SCWL hens, are considered to be important factors for the efficient production of IgY.

  20. Simultaneous mapping of membrane voltage and calcium in zebrafish heart in vivo reveals chamber-specific developmental transitions in ionic currents

    PubMed Central

    Hou, Jennifer H.; Kralj, Joel M.; Douglass, Adam D.; Engert, Florian; Cohen, Adam E.

    2014-01-01

    The cardiac action potential (AP) and the consequent cytosolic Ca2+ transient are key indicators of cardiac function. Natural developmental processes, as well as many drugs and pathologies change the waveform, propagation, or variability (between cells or over time) of these parameters. Here we apply a genetically encoded dual-function calcium and voltage reporter (CaViar) to study the development of the zebrafish heart in vivo between 1.5 and 4 days post fertilization (dpf). We developed a high-sensitivity spinning disk confocal microscope and associated software for simultaneous three-dimensional optical mapping of voltage and calcium. We produced a transgenic zebrafish line expressing CaViar under control of the heart-specific cmlc2 promoter, and applied ion channel blockers at a series of developmental stages to map the maturation of the action potential in vivo. Early in development, the AP initiated via a calcium current through L-type calcium channels. Between 90 and 102 h post fertilization (hpf), the ventricular AP switched to a sodium-driven upswing, while the atrial AP remained calcium driven. In the adult zebrafish heart, a sodium current drives the AP in both the atrium and ventricle. Simultaneous voltage and calcium imaging with genetically encoded reporters provides a new approach for monitoring cardiac development, and the effects of drugs on cardiac function. PMID:25309445

  1. Simultaneous mapping of membrane voltage and calcium in zebrafish heart in vivo reveals chamber-specific developmental transitions in ionic currents.

    PubMed

    Hou, Jennifer H; Kralj, Joel M; Douglass, Adam D; Engert, Florian; Cohen, Adam E

    2014-01-01

    The cardiac action potential (AP) and the consequent cytosolic Ca(2+) transient are key indicators of cardiac function. Natural developmental processes, as well as many drugs and pathologies change the waveform, propagation, or variability (between cells or over time) of these parameters. Here we apply a genetically encoded dual-function calcium and voltage reporter (CaViar) to study the development of the zebrafish heart in vivo between 1.5 and 4 days post fertilization (dpf). We developed a high-sensitivity spinning disk confocal microscope and associated software for simultaneous three-dimensional optical mapping of voltage and calcium. We produced a transgenic zebrafish line expressing CaViar under control of the heart-specific cmlc2 promoter, and applied ion channel blockers at a series of developmental stages to map the maturation of the action potential in vivo. Early in development, the AP initiated via a calcium current through L-type calcium channels. Between 90 and 102 h post fertilization (hpf), the ventricular AP switched to a sodium-driven upswing, while the atrial AP remained calcium driven. In the adult zebrafish heart, a sodium current drives the AP in both the atrium and ventricle. Simultaneous voltage and calcium imaging with genetically encoded reporters provides a new approach for monitoring cardiac development, and the effects of drugs on cardiac function.

  2. Textile dyes induce toxicity on zebrafish early life stages.

    PubMed

    de Oliveira, Gisele Augusto Rodrigues; de Lapuente, Joaquín; Teixidó, Elisabet; Porredón, Constança; Borràs, Miquel; de Oliveira, Danielle Palma

    2016-02-01

    Textile manufacturing is one of the most polluting industrial sectors because of the release of potentially toxic compounds, such as synthetic dyes, into the environment. Depending on the class of the dyes, their loss in wastewaters can range from 2% to 50% of the original dye concentration. Consequently, uncontrolled use of such dyes can negatively affect human health and the ecological balance. The present study assessed the toxicity of the textile dyes Direct Black 38 (DB38), Reactive Blue 15 (RB15), Reactive Orange 16 (RO16), and Vat Green 3 (VG3) using zebrafish (Danio rerio) embryos for 144 h postfertilization (hpf). At the tested conditions, none of the dyes caused significant mortality. The highest RO16 dose significantly delayed or inhibited the ability of zebrafish embryos to hatch from the chorion after 96 hpf. From 120 hpf to 144 hpf, all the dyes impaired the gas bladder inflation of zebrafish larvae, DB38 also induced curved tail, and VG3 led to yolk sac edema in zebrafish larvae. Based on these data, DB38, RB15, RO16, and VG3 can induce malformations during embryonic and larval development of zebrafish. Therefore, it is essential to remove these compounds from wastewater or reduce their concentrations to safe levels before discharging textile industry effluents into the aquatic environment. © 2015 SETAC.

  3. Food safety effects of unabsorbed yolks in broilers

    In the developing avian embryo, the main energy source is the yolk. Toward the end of the incubation period, the remaining yolk sac is internalized into the abdominal cavity. At hatch, the remaining yolk comprises 20% of the chick’s body weight and provides the nutrients needed for maintenance. P...

  4. Effects of DHA-enriched hen egg yolk and L-cysteine supplementation on quality of cryopreserved boar semen

    PubMed Central

    Chanapiwat, Panida; Kaeoket, Kampon; Tummaruk, Padet

    2009-01-01

    The objective of the present study was to determine the effects of docosahexaenoic acid (DHA)-enriched hen egg yolks and L-cysteine supplementation on the qualities of the cryopreserved boar semen. A total of 15 ejaculates from 5 Pietrain boars were divided into 4 groups according to the compositions of the freezing extenders used, that is, normal hen egg yolk (group I), DHA-enriched hen egg yolk (group II), normal hen egg yolk with 5 mmol L−1 of cysteine supplementation (group III) and DHA-enriched hen egg yolk with 5 mmol L−1 of cysteine supplementation (group IV). The semen was cryopreserved using controlled rate freezer and was thawed at 50°C for 12 s. Progressive motility, sperm viability, acrosome integrity and functional integrity of sperm plasma membrane of the post-thawed semen were evaluated. The supplementation of L-cysteine in the freezing extender alone (group III) improved progressive motility (P < 0.05), and the supplementation of L-cysteine in combination with DHA-enriched hen egg yolk (group IV) improved both progressive motility (P < 0.05) and acrosome integrity (P < 0.01). The use of DHA-enriched hen egg yolk alone (group II) did not enhance any of the post-thawed semen qualities (P > 0.05). In conclusion, the supplementation of antioxidant L-cysteine alone or in combination with DHA-enriched hen egg yolk significantly improved the post-thawed semen qualities, especially progressive motility and acrosome integrity. PMID:19633681

  5. Isolation of Cholesterol from an Egg Yolk

    ERIC Educational Resources Information Center

    Taber, Douglass F.; Li, Rui; Anson, Cory M.

    2011-01-01

    A simple procedure for the isolation of the cholesterol, by hydrolysis and extraction followed by column chromatography, is described. The cholesterol can be further purified by complexation with oxalic acid. It can also be oxidized and conjugated to cholestenone. The source of the cholesterol is one egg yolk, which contains about 200 mg of…

  6. 21 CFR 160.180 - Egg yolks.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Egg yolks. 160.180 Section 160.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... the method prescribed in “Official Methods of Analysis of the Association of Official Analytical...

  7. Changes in ultrastructure and expression of steroidogenic factor-1 in ovaries of zebrafish Danio rerio exposed to glyphosate.

    PubMed

    Armiliato, Neide; Ammar, Dib; Nezzi, Luciane; Straliotto, Marcos; Muller, Yara M R; Nazari, Evelise M

    2014-01-01

    Glyphosate is a broad-spectrum organophosphate (OP) herbicide, highly soluble in water, and when applied in terrestrial systems it penetrates into soil, eventually reaching the aquatic community and affecting nontarget organisms. The aim of this study was to evaluate the toxicity of glyphosate on ovaries of zebrafish (Danio rerio). Ovaries (n = 18 per triplicate) were exposed to 65 μg/L of glyphosate [N-(phosphonomethyl) glycine] for 15 d. This concentration was determined according to Resolution 357/2005/CONAMA/Brazil, which establishes the permissible concentration of glyphosate in Brazilian inland waters. Nonexposed ovaries (n = 18 per triplicate) were used as control. Subsequently, morphology and expression of steroidogenic factor-1 (SF-1) of exposed and nonexposed ovaries was determined. No apparent changes were noted in general morphology of exposed and nonexposed ovaries. However, a significant increase in diameter of oocytes was observed after exposure to glyphosate. When ovarian ultrastructure was examined the presence of concentric membranes, appearing as myelin-like structures, associated with the external membranes of mitochondria and with yolk granules was found. After glyphosate exposure, immunohistochemistry and immunoblotting revealed greater expression of SF-1 in the oocytes, which suggests a relationship between oocyte growth and SF-1 expression. These subtle adverse effects of glyphosate on oocytes raised a potential concern for fish reproduction. These results contribute to understanding glyphosate-induced toxicity to nontarget organisms, showing subcellular and molecular impairments that may affect reproduction in +female fish.

  8. Clofibrate and gemfibrozil induce an embryonic malabsorption syndrome in zebrafish

    SciT

    Raldua, Demetrio; Andre, Michele; Babin, Patrick J.

    2008-05-01

    Nutrient availability is one of the major non-genetic factors determining embryonic growth and larval or fetal size. Due to the high human consumption of blood lipid regulators, fibrates have recently been reported as pollutants in rivers. Our study investigated the developmental toxicity of fibrates in zebrafish. Treatment with micromolar concentrations of clofibrate or gemfibrozil induced an embryonic malabsorption syndrome (EMS) with very little yolk consumption, resulting in small-sized larvae. This effect was reversible on removing the drug from the water. Clofibrate delayed hatching time and decreased the amount of oil red O lipid staining in the vasculature. It also inducedmore » higher density, round-shaped neuromuscular junctions associated with disorganization and less striation of muscular fibers, and pericardial edema, as well as impairing thyroid gland morphogenesis. acox1, apoa1 and mtp hybridization transcript signals were not affected in the yolk syncytial layer (YSL) after clofibrate exposure. Di-(2-ethylhexyl)-phthalate did not slow down yolk resorption, whereas brefeldin A induced EMS. These findings suggest that the inhibition of yolk sac resorption on exposure to fibrate is not at a pre-translational level or peroxisome proliferator-activated receptor alpha dependent and may be due to an inhibition of the YSL constitutive cell secretion. The effects of fibrates and the potential bioconcentration in eggs as well as the additive action of structurally related toxicants warrant an evaluation of the developmental impact of these compounds after long-term exposure at environmentally relevant concentrations. Fibrate-induced EMS in zebrafish seems useful for studying the morphogenetic consequences of impaired nutrient availability during the early stages of vertebrate development.« less

  9. Loss-of-function of the ciliopathy protein Cc2d2a disorganizes the vesicle fusion machinery at the periciliary membrane and indirectly affects Rab8-trafficking in zebrafish photoreceptors

    PubMed Central

    Gesemann, Matthias; Mateos, José M.; Barmettler, Gery; Forbes, Austin; Ziegler, Urs

    2017-01-01

    Ciliopathies are human disorders caused by dysfunction of primary cilia, ubiquitous organelles involved in transduction of environmental signals such as light sensation in photoreceptors. Concentration of signal detection proteins such as opsins in the ciliary membrane is achieved by RabGTPase-regulated polarized vesicle trafficking and by a selective barrier at the ciliary base, the transition zone (TZ). Dysfunction of the TZ protein CC2D2A causes Joubert/Meckel syndromes in humans and loss of ciliary protein localization in animal models, including opsins in retinal photoreceptors. The link between the TZ and upstream vesicle trafficking has been little explored to date. Moreover, the role of the small GTPase Rab8 in opsin-carrier vesicle (OCV) trafficking has been recently questioned in a mouse model. Using correlative light and electron microscopy and live imaging in zebrafish photoreceptors, we provide the first live characterization of Rab8-mediated trafficking in photoreceptors in vivo. Our results support a possibly redundant role for both Rab8a/b paralogs in OCV trafficking, based on co-localization of Rab8 and opsins in vesicular structures, and joint movement of Rab8-tagged particles with opsin. We further investigate the role of the TZ protein Cc2d2a in Rab8-mediated trafficking using cc2d2a zebrafish mutants and identify a requirement for Cc2d2a in the latest step of OCV trafficking, namely vesicle fusion. Progressive accumulation of opsin-containing vesicles in the apical portion of photoreceptors lacking Cc2d2a is caused by disorganization of the vesicle fusion machinery at the periciliary membrane with mislocalization and loss of the t-SNAREs SNAP25 and Syntaxin3 and of the exocyst component Exoc4. We further observe secondary defects on upstream Rab8-trafficking with cytoplasmic accumulation of Rab8. Taken together, our results support participation of Rab8 in OCV trafficking and identify a novel role for the TZ protein Cc2d2a in fusion of incoming

  10. Loss-of-function of the ciliopathy protein Cc2d2a disorganizes the vesicle fusion machinery at the periciliary membrane and indirectly affects Rab8-trafficking in zebrafish photoreceptors.

    PubMed

    Ojeda Naharros, Irene; Gesemann, Matthias; Mateos, José M; Barmettler, Gery; Forbes, Austin; Ziegler, Urs; Neuhauss, Stephan C F; Bachmann-Gagescu, Ruxandra

    2017-12-01

    Ciliopathies are human disorders caused by dysfunction of primary cilia, ubiquitous organelles involved in transduction of environmental signals such as light sensation in photoreceptors. Concentration of signal detection proteins such as opsins in the ciliary membrane is achieved by RabGTPase-regulated polarized vesicle trafficking and by a selective barrier at the ciliary base, the transition zone (TZ). Dysfunction of the TZ protein CC2D2A causes Joubert/Meckel syndromes in humans and loss of ciliary protein localization in animal models, including opsins in retinal photoreceptors. The link between the TZ and upstream vesicle trafficking has been little explored to date. Moreover, the role of the small GTPase Rab8 in opsin-carrier vesicle (OCV) trafficking has been recently questioned in a mouse model. Using correlative light and electron microscopy and live imaging in zebrafish photoreceptors, we provide the first live characterization of Rab8-mediated trafficking in photoreceptors in vivo. Our results support a possibly redundant role for both Rab8a/b paralogs in OCV trafficking, based on co-localization of Rab8 and opsins in vesicular structures, and joint movement of Rab8-tagged particles with opsin. We further investigate the role of the TZ protein Cc2d2a in Rab8-mediated trafficking using cc2d2a zebrafish mutants and identify a requirement for Cc2d2a in the latest step of OCV trafficking, namely vesicle fusion. Progressive accumulation of opsin-containing vesicles in the apical portion of photoreceptors lacking Cc2d2a is caused by disorganization of the vesicle fusion machinery at the periciliary membrane with mislocalization and loss of the t-SNAREs SNAP25 and Syntaxin3 and of the exocyst component Exoc4. We further observe secondary defects on upstream Rab8-trafficking with cytoplasmic accumulation of Rab8. Taken together, our results support participation of Rab8 in OCV trafficking and identify a novel role for the TZ protein Cc2d2a in fusion of incoming

  11. Lipidomics and H218O labeling techniques reveal increased remodeling of DHA-containing membrane phospholipids associated with abnormal locomotor responses in α-tocopherol deficient zebrafish (danio rerio) embryos

    PubMed Central

    McDougall, Melissa Q.; Choi, Jaewoo; Stevens, Jan F.; Truong, Lisa; Tanguay, Robert L.; Traber, Maret G.

    2016-01-01

    We hypothesized that vitamin E (α-tocopherol) is required by the developing embryonic brain to prevent depletion of highly polyunsaturated fatty acids, especially docosahexaenoic acid (DHA, 22:6), the loss of which we predicted would underlie abnormal morphological and behavioral outcomes. Therefore, we fed adult 5D zebrafish (Danio rerio) defined diets without (E−) or with added α-tocopherol (E+, 500 mg RRR-α-tocopheryl acetate/kg diet) for a minimum of 80 days, and then spawned them to obtain E− and E+ embryos. The E− compared with E+ embryos were 82% less responsive (p<0.01) to a light/dark stimulus at 96 h post-fertilization (hpf), demonstrating impaired locomotor behavior, even in the absence of gross morphological defects. Evaluation of phospholipid (PL) and lysophospholipid (lyso-PL) composition using untargeted lipidomics in E− compared with E+ embryos at 24, 48, 72, and 120 hpf showed that four PLs and three lyso-PLs containing docosahexaenoic acid (DHA), including lysophosphatidylcholine (LPC 22:6, required for transport of DHA into the brain, p<0.001), were at lower concentrations in E− at all time-points. Additionally, H218O labeling experiments revealed enhanced turnover of LPC 22:6 (p<0.001) and three other DHA-containing PLs in the E− compared with the E+ embryos, suggesting that increased membrane remodeling is a result of PL depletion. Together, these data indicate that α-tocopherol deficiency in the zebrafish embryo causes the specific depletion and increased turnover of DHA-containing PL and lyso-PLs, which may compromise DHA delivery to the brain and thereby contribute to the functional impairments observed in E− embryos. PMID:26774753

  12. Lxr regulates lipid metabolic and visual perception pathways during zebrafish development.

    PubMed

    Pinto, Caroline Lucia; Kalasekar, Sharanya Maanasi; McCollum, Catherine W; Riu, Anne; Jonsson, Philip; Lopez, Justin; Swindell, Eric C; Bouhlatouf, Abdel; Balaguer, Patrick; Bondesson, Maria; Gustafsson, Jan-Åke

    2016-01-05

    The Liver X Receptors (LXRs) play important roles in multiple metabolic pathways, including fatty acid, cholesterol, carbohydrate and energy metabolism. To expand the knowledge of the functions of LXR signaling during embryonic development, we performed a whole-genome microarray analysis of Lxr target genes in zebrafish larvae treated with either one of the synthetic LXR ligands T0901317 or GW3965. Assessment of the biological processes enriched by differentially expressed genes revealed a prime role for Lxr in regulating lipid metabolic processes, similarly to the function of LXR in mammals. In addition, exposure to the Lxr ligands induced changes in expression of genes in the neural retina and lens of the zebrafish eye, including the photoreceptor guanylate cyclase activators and lens gamma crystallins, suggesting a potential novel role for Lxr in modulating the transcription of genes associated with visual function in zebrafish. The regulation of expression of metabolic genes was phenotypically reflected in an increased absorption of yolk in the zebrafish larvae, and changes in the expression of genes involved in visual perception were associated with morphological alterations in the retina and lens of the developing zebrafish eye. The regulation of expression of both lipid metabolic and eye specific genes was sustained in 1 month old fish. The transcriptional networks demonstrated several conserved effects of LXR activation between zebrafish and mammals, and also identified potential novel functions of Lxr, supporting zebrafish as a promising model for investigating the role of Lxr during development. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Lxr regulates lipid metabolic and visual perception pathways during zebrafish development

    PubMed Central

    Pinto, Caroline Lucia; Kalasekar, Sharanya Maanasi; McCollum, Catherine W.; Riu, Anne; Jonsson, Philip; Lopez, Justin; Swindell, Eric; Bouhlatouf, Abdel; Balaguer, Patrick; Bondesson, Maria; Gustafsson, Jan-Åke

    2015-01-01

    The Liver X Receptors (LXRs) play important roles in multiple metabolic pathways, including fatty acid, cholesterol, carbohydrate and energy metabolism. To expand the knowledge of the functions of LXR signaling during embryonic development, we performed a whole-genome microarray analysis of Lxr target genes in zebrafish larvae treated with either one of the synthetic LXR ligands T0901317 or GW3965. Assessment of the biological processes enriched by differentially expressed genes revealed a prime role for Lxr in regulating lipid metabolic processes, similarly to the function of LXR in mammals. In addition, exposure to the Lxr ligands induced changes in expression of genes in the neural retina and lens of the zebrafish eye, including the photoreceptor guanylate cyclase activators and lens gamma crystallins, suggesting a potential novel role for Lxr in modulating the transcription of genes associated with visual function in zebrafish. The regulation of expression of metabolic genes was phenotypically reflected in an increased absorption of yolk in the zebrafish larvae, and changes in the expression of genes involved in visual perception were associated with morphological alterations in the retina and lens of the developing zebrafish eye. The regulation of expression of both lipid metabolic and eye specific genes was sustained in 1 month old fish. The transcriptional networks demonstrated several conserved effects of LXR activation between zebrafish and mammals, and also identified potential novel functions of Lxr, supporting zebrafish as a promising model for investigating the role of Lxr during development. PMID:26427652

  14. Imaging residue transfer into egg yolks.

    PubMed

    Donoghue, D J; Myers, K

    2000-12-01

    Prediction models for residue transfer into eggs are being developed. Recent results indicate that the developing egg yolk serves as an important storage depot for chemical residues. The current study was conducted to visualize incorporation and potential compartmentalization of drug residues in developing egg yolks. To this end, the drug magnevist was injected into hens to evaluate drug transfer into either early- or late-developing yolks. High-resolution magnetic resonance images (MRI) of drug residues in eggs were acquired using a 1.5 T Siemens Magnetom clinical scanner. A 10-cm circular surface coil was used for receiving the magnetic resonance signal. The eggs were positioned inside the coil cavity for an improved signal to noise ratio (SNR). Gradient-echo images were used to locate the centers of the eggs and to prescribe the position of the high-resolution image slab. The images were recorded using an inversion time (T1) weighted magnetization-prepared, rapid acquisition, gradient-recalled-echo (MPRAGE) pulse sequence. The sequence parameters used were as follows: repetition time (TR) equals 12 ms, echo time (TE) equals 5 ms, field of view (FOV) equals 200, TI = 10 ms, 1.25-mm slice thickness, and a matrix of 200 x 256. Following dosing, images of drug residues in eggs indicate that drugs can be incorporated and compartmentalized into ring structures within individual developing egg yolks. These results have significant human food safety implications because even after only a single dose, sequestered drug residues may be stored and later released to contaminate eggs for days to weeks after dosing.

  15. The primary role of zebrafish nanog is in extra-embryonic tissue.

    PubMed

    Gagnon, James A; Obbad, Kamal; Schier, Alexander F

    2018-01-09

    The role of the zebrafish transcription factor Nanog has been controversial. It has been suggested that Nanog is primarily required for the proper formation of the extra-embryonic yolk syncytial layer (YSL) and only indirectly regulates gene expression in embryonic cells. In an alternative scenario, Nanog has been proposed to directly regulate transcription in embryonic cells during zygotic genome activation. To clarify the roles of Nanog, we performed a detailed analysis of zebrafish nanog mutants. Whereas zygotic nanog mutants survive to adulthood, maternal-zygotic (MZ nanog ) and maternal mutants exhibit developmental arrest at the blastula stage. In the absence of Nanog, YSL formation and epiboly are abnormal, embryonic tissue detaches from the yolk, and the expression of dozens of YSL and embryonic genes is reduced. Epiboly defects can be rescued by generating chimeric embryos of MZ nanog embryonic tissue with wild-type vegetal tissue that includes the YSL and yolk cell. Notably, cells lacking Nanog readily respond to Nodal signals and when transplanted into wild-type hosts proliferate and contribute to embryonic tissues and adult organs from all germ layers. These results indicate that zebrafish Nanog is necessary for proper YSL development but is not directly required for embryonic cell differentiation. © 2018. Published by The Company of Biologists Ltd.

  16. In Vivo Cardiotoxicity Induced by Sodium Aescinate in Zebrafish Larvae.

    PubMed

    Liang, Jinfeng; Jin, Wangdong; Li, Hongwen; Liu, Hongcui; Huang, Yanfeng; Shan, Xiaowen; Li, Chunqi; Shan, Letian; Efferth, Thomas

    2016-02-23

    Sodium aescinate (SA) is a widely-applied triterpene saponin product derived from horse chestnut seeds, possessing vasoactive and organ-protective activities with oral or injection administration in the clinic. To date, no toxicity or adverse events in SA have been reported, by using routine models (in vivo or in vitro), which are insufficient to predict all aspects of its pharmacological and toxicological actions. In this study, taking advantage of transparent zebrafish larvae (Danio rerio), we evaluated cardiovascular toxicity of SA at doses of 1/10 MNLC, 1/3 MNLC, MNLC and LC10 by yolk sac microinjection. The qualitative and quantitative cardiotoxicity in zebrafish was assessed at 48 h post-SA treatment, using specific phenotypic endpoints: heart rate, heart rhythm, heart malformation, pericardial edema, circulation abnormalities, thrombosis and hemorrhage. The results showed that SA at 1/10 MNLC and above doses could induce obvious cardiac and pericardial malformations, whilst 1/3 MNLC and above doses could induce significant cardiac malfunctions (heart rate and circulation decrease/absence), as compared to untreated or vehicle-treated control groups. Such cardiotoxic manifestations occurred in more than 50% to 100% of all zebrafish treated with SA at MNLC and LC10. Our findings have uncovered the potential cardiotoxicity of SA for the first time, suggesting more attention to the risk of its clinical application. Such a time- and cost-saving zebrafish cardiotoxicity assay is very valid and reliable for rapid prediction of compound toxicity during drug research and development.

  17. In vitro assessment of soybean lecithin and egg yolk based diluents for cryopreservation of goat semen.

    PubMed

    Salmani, Hossein; Towhidi, Armin; Zhandi, Mahdi; Bahreini, Majid; Sharafi, Mohsen

    2014-04-01

    Soybean lecithin is a suitable plant-based cryoprotectant for freezing ruminant sperm. Optimum level of lecithin was not clear for goat semen cryopreservation. The objective of this study was to investigate the effects of different levels of soybean lecithin in semen extender on post-thaw sperm quality including CASA-motion parameters, viability, plasma membrane integrity and lipid peroxidation. Semen samples were collected from 4 Mahabadi bucks using an artificial vagina. Different concentrations of soy lecithin (SL, 0.5%, 1%, 1.5%, 2% and 2.5% w/v) were compared to 15% (v/v) egg yolk-based extender (TR-EY). No significant difference was observed for sperm progressive motility, viability or plasma membrane integrity in 1.5% SL media (33.8%, 66%, and 62.7%, respectively) and TR-EY medium (35.4%, 67.2%, and 64.9%, respectively). Sperm motion characteristics (VAP, VSL, VCL, ALH and LIN) and rapid spermatozoa were improved with extender containing 1% and 1.5% SL, compared to TR-EY extender. Furthermore, egg yolk produced significantly higher malondialdehyde (4.02±0.21) than other groups. Results suggest that the optimal lecithin concentration in the semen extender was 1.5% and also soy lecithin can substitute for egg yolk during cryopreservation for caprine sperm. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Teratogenic responses of zebrafish embryos to decabromodiphenyl ether (BDE-209) in the presence of nano-SiO2 particles.

    PubMed

    Chao, Shu-Ju; Huang, Chin Pao; Chen, Pei-Chung; Huang, Chihpin

    2017-07-01

    This study investigated the influence of nano-SiO 2 particles (nSiO 2 ) on the teratogenic responses of zebrafish embryos to decabromodiphenyl ether (BDE-209). Zebrafish embryos were exposed to BDE-209 in the absence and presence of nSiO 2 for 96 h post fertilization (hpf). Results showed that formation of nSiO 2 -BDE-209 associates promoted both extracellular and intracellular uptake of BDE-209 by zebrafish embryos, thereby increasing the bioconcentration of BDE-209 on the chorion surface and the embryos. Results also showed embryos delay hatching temporarily when co-exposure to BDE-209 and nSiO 2 at 60 hpf. Furthermore, there was heartbeat decline (28.3 beats/10s) and increase in irregular heartbeat (45.8%) in zebrafish larvae at 96 hpf, compared to the sole exposure to BDE-209 (32.7 beats/10s and 0%). Malformation in terms of spinal curvature (SC), pericardial edema (PE) and yolk sac edema (YSE) were observed on zebrafish larvae at 33.9, 23.4, and 18%, respectively. Overall, abnormal development of zebrafish was apparent when co-exposure to BDE-209 and nSiO 2 . All relevant evidence considered, nSiO 2 could facilitate the transport of BDE-209 towards zebrafish embryos and negatively impact the development of zebrafish. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Comprehensive and quantitative proteomic analyses of zebrafish plasma reveals conserved protein profiles between genders and between zebrafish and human.

    PubMed

    Li, Caixia; Tan, Xing Fei; Lim, Teck Kwang; Lin, Qingsong; Gong, Zhiyuan

    2016-04-13

    Omic approaches have been increasingly used in the zebrafish model for holistic understanding of molecular events and mechanisms of tissue functions. However, plasma is rarely used for omic profiling because of the technical challenges in collecting sufficient blood. In this study, we employed two mass spectrometric (MS) approaches for a comprehensive characterization of zebrafish plasma proteome, i.e. conventional shotgun liquid chromatography-tandem mass spectrometry (LC-MS/MS) for an overview study and quantitative SWATH (Sequential Window Acquisition of all THeoretical fragment-ion spectra) for comparison between genders. 959 proteins were identified in the shotgun profiling with estimated concentrations spanning almost five orders of magnitudes. Other than the presence of a few highly abundant female egg yolk precursor proteins (vitellogenins), the proteomic profiles of male and female plasmas were very similar in both number and abundance and there were basically no other highly gender-biased proteins. The types of plasma proteins based on IPA (Ingenuity Pathway Analysis) classification and tissue sources of production were also very similar. Furthermore, the zebrafish plasma proteome shares significant similarities with human plasma proteome, in particular in top abundant proteins including apolipoproteins and complements. Thus, the current study provided a valuable dataset for future evaluation of plasma proteins in zebrafish.

  20. Comprehensive and quantitative proteomic analyses of zebrafish plasma reveals conserved protein profiles between genders and between zebrafish and human

    PubMed Central

    Li, Caixia; Tan, Xing Fei; Lim, Teck Kwang; Lin, Qingsong; Gong, Zhiyuan

    2016-01-01

    Omic approaches have been increasingly used in the zebrafish model for holistic understanding of molecular events and mechanisms of tissue functions. However, plasma is rarely used for omic profiling because of the technical challenges in collecting sufficient blood. In this study, we employed two mass spectrometric (MS) approaches for a comprehensive characterization of zebrafish plasma proteome, i.e. conventional shotgun liquid chromatography-tandem mass spectrometry (LC-MS/MS) for an overview study and quantitative SWATH (Sequential Window Acquisition of all THeoretical fragment-ion spectra) for comparison between genders. 959 proteins were identified in the shotgun profiling with estimated concentrations spanning almost five orders of magnitudes. Other than the presence of a few highly abundant female egg yolk precursor proteins (vitellogenins), the proteomic profiles of male and female plasmas were very similar in both number and abundance and there were basically no other highly gender-biased proteins. The types of plasma proteins based on IPA (Ingenuity Pathway Analysis) classification and tissue sources of production were also very similar. Furthermore, the zebrafish plasma proteome shares significant similarities with human plasma proteome, in particular in top abundant proteins including apolipoproteins and complements. Thus, the current study provided a valuable dataset for future evaluation of plasma proteins in zebrafish. PMID:27071722

  1. Cryopreservation of Dog Semen in a Tris Extender with 1% or 2% Soya Bean Lecithin as a Replacement of Egg Yolk.

    PubMed

    Axnér, E; Lagerson, E

    2016-04-01

    Egg yolk is usually included in extenders used for preservation of dog semen. Lecithin is an interesting animal-protein free alternative to egg yolk for semen preservation. The aim of our study was to evaluate soya bean lecithin for cryopreservation of dog semen. Five ejaculate replicates were divided in three equal parts, centrifuged and each pellet diluted with one of the three Tris-based extenders containing 20% egg yolk, 1% soya bean lecithin or 2% soya bean lecithin. Extended semen was loaded in 0.5-ml straws, cooled and diluted a second time and frozen in liquid nitrogen vapours. Sperm motility parameters (CASA), acrosome integrity (FITC-PNA/PI) and sperm membrane integrity (C-FDA) were evaluated 5 min post-thaw and after 2 and 4 h of incubation. Total motility was significantly better in the egg yolk extender than in any of the lecithin-based extender and was better in the 1% lecithin extender than in the 2% lecithin extender. Sperm membrane integrity was significantly better in the egg yolk extender than in any of the lecithin-based extenders but did not differ significantly between the 1% and 2% lecithin extenders. Acrosome integrity was significantly better in the egg yolk extender than in the 2% lecithin extender but did not differ between the egg yolk extender and the 1% lecithin extender or between the two lecithin extenders. In conclusion, egg yolk was superior to lecithin in our study. The extender with 1% lecithin preserved sperm motility better than the extender with 2% lecithin. © 2016 Blackwell Verlag GmbH.

  2. The influence of environmental P(O(2)) on hemoglobin oxygen saturation in developing zebrafish Danio rerio.

    PubMed

    Grillitsch, Sandra; Medgyesy, Nikolaus; Schwerte, Thorsten; Pelster, Bernd

    2005-01-01

    Several studies suggest that during early larval development of lower vertebrates convective blood flow is not essential to supply oxygen to the tissues, but information about the oxygenation status of larvae during the time of cutaneous respiration is still missing. If convective oxygen transport contributes to the oxygen supply to tissues, venous blood in the central circulatory system should be partly deoxygenated, and hyperoxia should increase the oxygen saturation of the hemoglobin. To analyze the changes in hemoglobin oxygen saturation induced by hyperoxic incubation, zebrafish larvae were incubated in a tiny chamber between polytetrafluoroethylene membranes (Teflon), so that the oxygen supply could be rapidly modified. Hemoglobin oxygen saturation was measured in vivo by combining video imaging techniques with a spectrophotometrical analysis of hemoglobin light absorption at specific wavelengths for maximal absorption of oxygenated and deoxygenated blood (413 nm and 431 nm, respectively) under normoxic conditions and after a 10 min period of hyperoxia (P(O(2))=100 kPa), assuming that at a P(O(2)) of 100 kPa the hemoglobin is fully saturated. The results demonstrated that red blood cell oxygenation of zebrafish larvae at 4 days post fertilization (d.p.f.), 5 d.p.f. and 12 d.p.f. could be increased by hyperoxia. The data suggest that at the time of yolk sac degradation (i.e. 4 d.p.f. and 5 d.p.f.), when the total surface area of the animal is reduced, bulk diffusion of oxygen may not be sufficient to prevent a partial deoxygenation of the hemoglobin. The decrease in hemoglobin oxygenation observed at 12 d.p.f. confirms earlier studies indicating that at 12-14 d.p.f., convective oxygen transport becomes necessary to ensure oxygen supply to the growing tissues.

  3. Body Mass Parameters, Lipid Profiles and Protein Contents of Zebrafish Embryos and Effects of 2,4-Dinitrophenol Exposure

    PubMed Central

    Hachicho, Nancy; Reithel, Sarah; Miltner, Anja; Heipieper, Hermann J.; Küster, Eberhard; Luckenbach, Till

    2015-01-01

    Morphology and physiology of fish embryos undergo dramatic changes during their development until the onset of feeding, supplied only by endogenous yolk reserves. For obtaining an insight how these restructuring processes are reflected by body mass related parameters, dry weights (dw), contents of the elements carbon and nitrogen and lipid and protein levels were quantified in different stages within the first four days of embryo development of the zebrafish (Danio rerio). The data show age dependent changes in tissue composition. Dry weights decreased significantly from 79μgdw/egg at 0hours post fertilization (hpf) to 61 μgdw/egg after 96 hpf. The amounts of total carbon fluctuated between 460 mg g-1 and 540 mg g-1 dw, nitrogen was at about 100 mg g-1 dw and total fatty acids were between 48–73 mg g-1 dw. In contrast to these parameters that remained relatively constant, the protein content, which was 240 mg g-1 at 0 hpf, showed an overall increase of about 40%. Comparisons of intact eggs and dechorionated embryos at stages prior to hatching (24, 30, 48 hpf) showed that the differences seen for dry weight and for carbon and nitrogen contents became smaller at more advanced stages, consistent with transition of material from the chorion to embryo tissue. Further, we determined the effect of 2,4-dinitrophenol at a subacutely toxic concentration (14 μM, LC10) as a model chemical challenge on the examined body mass related parameters. The compound caused significant decreases in phospholipid and glycolipid fatty acid contents along with a decrease in the phospholipid fatty acid unsaturation index. No major changes were observed for the other examined parameters. Lipidomic studies as performed here may thus be useful for determining subacute effects of lipophilic organic compounds on lipid metabolism and on cellular membranes of zebrafish embryos. PMID:26292096

  4. Dissection and lateral mounting of zebrafish embryos: analysis of spinal cord development.

    PubMed

    Beck, Aaron P; Watt, Roland M; Bonner, Jennifer

    2014-02-28

    The zebrafish spinal cord is an effective investigative model for nervous system research for several reasons. First, genetic, transgenic and gene knockdown approaches can be utilized to examine the molecular mechanisms underlying nervous system development. Second, large clutches of developmentally synchronized embryos provide large experimental sample sizes. Third, the optical clarity of the zebrafish embryo permits researchers to visualize progenitor, glial, and neuronal populations. Although zebrafish embryos are transparent, specimen thickness can impede effective microscopic visualization. One reason for this is the tandem development of the spinal cord and overlying somite tissue. Another reason is the large yolk ball, which is still present during periods of early neurogenesis. In this article, we demonstrate microdissection and removal of the yolk in fixed embryos, which allows microscopic visualization while preserving surrounding somite tissue. We also demonstrate semipermanent mounting of zebrafish embryos. This permits observation of neurodevelopment in the dorso-ventral and anterior-posterior axes, as it preserves the three-dimensionality of the tissue.

  5. Dissection and Lateral Mounting of Zebrafish Embryos: Analysis of Spinal Cord Development

    PubMed Central

    Beck, Aaron P.; Watt, Roland M.; Bonner, Jennifer

    2014-01-01

    The zebrafish spinal cord is an effective investigative model for nervous system research for several reasons. First, genetic, transgenic and gene knockdown approaches can be utilized to examine the molecular mechanisms underlying nervous system development. Second, large clutches of developmentally synchronized embryos provide large experimental sample sizes. Third, the optical clarity of the zebrafish embryo permits researchers to visualize progenitor, glial, and neuronal populations. Although zebrafish embryos are transparent, specimen thickness can impede effective microscopic visualization. One reason for this is the tandem development of the spinal cord and overlying somite tissue. Another reason is the large yolk ball, which is still present during periods of early neurogenesis. In this article, we demonstrate microdissection and removal of the yolk in fixed embryos, which allows microscopic visualization while preserving surrounding somite tissue. We also demonstrate semipermanent mounting of zebrafish embryos. This permits observation of neurodevelopment in the dorso-ventral and anterior-posterior axes, as it preserves the three-dimensionality of the tissue. PMID:24637734

  6. Pre-gastrula expression of zebrafish extraembryonic genes

    PubMed Central

    2010-01-01

    Background Many species form extraembryonic tissues during embryogenesis, such as the placenta of humans and other viviparous mammals. Extraembryonic tissues have various roles in protecting, nourishing and patterning embryos. Prior to gastrulation in zebrafish, the yolk syncytial layer - an extraembryonic nuclear syncytium - produces signals that induce mesoderm and endoderm formation. Mesoderm and endoderm precursor cells are situated in the embryonic margin, an external ring of cells along the embryo-yolk interface. The yolk syncytial layer initially forms below the margin, in a domain called the external yolk syncytial layer (E-YSL). Results We hypothesize that key components of the yolk syncytial layer's mesoderm and endoderm inducing activity are expressed as mRNAs in the E-YSL. To identify genes expressed in the E-YSL, we used microarrays to compare the transcription profiles of intact pre-gastrula embryos with pre-gastrula embryonic cells that we had separated from the yolk and yolk syncytial layer. This identified a cohort of genes with enriched expression in intact embryos. Here we describe our whole mount in situ hybridization analysis of sixty-eight of them. This includes ten genes with E-YSL expression (camsap1l1, gata3, znf503, hnf1ba, slc26a1, slc40a1, gata6, gpr137bb, otop1 and cebpa), four genes with expression in the enveloping layer (EVL), a superficial epithelium that protects the embryo (zgc:136817, zgc:152778, slc14a2 and elovl6l), three EVL genes whose expression is transiently confined to the animal pole (elovl6l, zgc:136359 and clica), and six genes with transient maternal expression (mtf1, wu:fj59f04, mospd2, rftn2, arrdc1a and pho). We also assessed the requirement of Nodal signaling for the expression of selected genes in the E-YSL, EVL and margin. Margin expression was Nodal dependent for all genes we tested, including the concentrated margin expression of an EVL gene: zgc:110712. All other instances of EVL and E-YSL expression that we

  7. Effects of particle size and coating on nanoscale Ag and TiO₂ exposure in zebrafish (Danio rerio) embryos.

    PubMed

    Osborne, Olivia J; Johnston, Blair D; Moger, Julian; Balousha, Mohammed; Lead, Jamie R; Kudoh, Tetsuhiro; Tyler, Charles R

    2013-12-01

    Manufactured metal (oxide) nanoparticles are entering the aquatic environment with little understanding on their potential health impacts for exposed organisms. Adopting an integrative approach, we investigated effects of particle size and coating on biological responses for two of the most commonly used metal (oxide) nanoscale particles, silver (Ag) and titanium dioxide (TiO₂) in zebrafish embryos. Titanium dioxide nanoparticles (nominally, 4 nm, 10 nm, 30 nm and 134 nm) had little or no toxicity on the endpoints measured. Ag both in nano form (10 nm and 35 nm) and its larger counterpart (600-1600 nm) induced dose-dependent lethality and morphological defects, occurring predominantly during gastrula stage. Of the silver material tested 10 nm nanoparticles appeared to be the most toxic. Coating Ag nanoparticles with citrate or fulvic acid decreased toxicity significantly. In situ hybridisation analysis identified the yolk syncytial layer (YSL) as a target tissue for Ag-nano toxicity where there was a significant induction of the heavy metal stress response gene, metallothionein 2 (Mt2) at sub-lethal exposures. Coherent Anti-stroke Raman Scattering (CARS) microscopy provided no evidence for silver particles crossing the chorionic membrane in exposed embryos. Collectively, our data suggest that silver ions play a major role in the toxicity of Ag nanoparticles.

  8. Testing an egg yolk supplemented diet on boars to aid in sperm adaptation at 5°C.

    PubMed

    Casas, Isabel; Miller-Lux, Yvonne; Osborne, Betty; Bonet, Sergi; Althouse, Gary C

    2015-01-01

    In many species, extended semen can be stored at low temperatures to slow bacterial growth. However, boar semen performs poorly at temperatures below 15 °C and this poses unique challenges, as it is not easy to maintain a constant 15-19 °C during shipment. Some extenders have been formulated with egg yolk for storage at 5 °C but the addition of egg yolk is not applicable in the majority of commercial operations. The purpose of this study was to evaluate if boar dietary supplementation with powdered egg yolk imparts any protective effects on sperm quality when stored at 15 °C and 5 °C for up to 11 days in a conventional extender. Ten boars were fed a commercial diet with the addition of 0.11 Kg of powdered egg yolk for 10 weeks. Ejaculates collected on weeks 4, 6, 8, and 10 were processed for storage at both 15 °C and 5 °C and compared with ejaculates from boars fed a standard diet. Throughout an 11-day storage period, sperm quality was assessed including several motility and morphologic parameters and select plasma membrane properties (fluidity, integrity, and triacylglycerol content). Linear regression models were used to describe effects of treatment, storage day, week and temperature on all sperm parameters. Overall, there were minimal beneficial effects of egg yolk treatment on sperm quality parameters. Sperm from egg yolk supplemented boars did have a slower decline in viability and plasma membrane fluidity than that observed in the control sperm when stored at 5 °C (p < 0.001). Additionally, there was an increase in total morphologic abnormalities in sperm from egg yolk fed boars compared to controls at week 10 (p <  .001). In conclusion, the results of this study do not support a significant benefit to sperm quality or resistance to cold storage when feeding a 10-week dietary supplementation of 0.11 Kg powdered egg yolk to crossbred boars.

  9. Characterization of zebrafish dysferlin by morpholino knockdown

    SciT

    Kawahara, Genri; Serafini, Peter R.; Myers, Jennifer A.

    2011-09-23

    Highlights: {yields} cDNAs of zebrafish dysferlin were cloned (6.3 kb). {yields} The dysferlin expression was detected in skeletal muscle, heart and eye. {yields} Injection of antisense morpholinos to dysferlin caused marked muscle disorganization. {yields} Zebrafish dysferlin expression may be involved in stabilizing muscle structures. -- Abstract: Mutations in the gene encoding dysferlin cause two distinct muscular dystrophy phenotypes: limb-girdle muscular dystrophy type 2B (LGMD-2B) and Miyoshi myopathy (MM). Dysferlin is a large transmembrane protein involved in myoblast fusion and membrane resealing. Zebrafish represent an ideal animal model to use for studying muscle disease including abnormalities of dysferlin. cDNAs of zebrafishmore » dysferlin were cloned (6.3 kb) and the predicted amino acid sequences, showed 68% similarity to predicted amino acid sequences of mammalian dysferlin. The expression of dysferlin was mainly in skeletal muscle, heart and eye, and the expression could be detected as early as 11 h post fertilization (hpf). Three different antisense oligonucleotide morpholinos were targeted to inhibit translation of this dysferlin mRNA and the morpholino-injected fish showed marked muscle disorganization which could be detected by birefringence assay. Western blot analysis using dysferlin antibodies showed that the expression of dysferlin was reduced in each of the three morphants. Dysferlin expression was shown to be reduced at the myosepta of zebrafish muscle using immunohistochemistry, although the expression of other muscle membrane components, dystrophin, laminin, {beta}-dystroglycan were detected normally. Our data suggest that zebrafish dysferlin expression is involved in stabilizing muscle structures and its downregulation causes muscle disorganization.« less

  10. Ovarian yolk sac tumour in a girl - case report.

    PubMed

    Sharma, Charu; Shah, Hemanshi; Sisodiya Shenoy, Neha; Makhija, Deepa; Waghmare, Mukta

    2017-01-01

    Yolk sac tumours are rare ovarian malignancies accounting for less than 1% of malignant ovarian germ cell tumours. They are mostly seen in adolescents and young women and are usually unilateral making fertility preservation imperative. Raised alpha-feto protein level is the hallmark of this tumour. We describe stage III yolk sac tumour in a girl child.

  11. Enteral Formula Containing Egg Yolk Lecithin Improves Diarrhea.

    PubMed

    Akashi, Tetsuro; Muto, Ayano; Takahashi, Yayoi; Nishiyama, Hiroshi

    2017-09-01

    Diarrhea often occurs during enteral nutrition. Recently, several reports showed that diarrhea improves by adding egg yolk lecithin, an emulsifier, in an enteral formula. Therefore, we evaluated if this combination could improve diarrhea outcomes. We retrospectively investigated the inhibitory effects on watery stools by replacing a polymeric fomula with that containing egg yolk lecithin. Then, we investigated the emulsion stability in vitro. Next, we examined the lipid absorption using different emulsifiers among bile duct-ligated rats and assessed whether egg yolk lecithin, medium-chain triglyceride, and dietary fiber can improve diarrhea outcomes in a rat model of short bowel syndrome. Stool consistency or frequency improved on the day after using the aforementioned combination in 13/14 patients. Average particle size of the egg yolk lecithin emulsifier did not change by adding artificial gastric juice, whereas that of soy lecithin and synthetic emulsifiers increased. Serum triglyceride concentrations were significantly higher in the egg yolk lecithin group compared with the soybean lecithin and synthetic emulsifier groups in bile duct-ligated rats. In rats with short bowels, the fecal consistency was a significant looser the dietary fiber (+) group than the egg yolk lecithin (+) groups from day 6 of test meal feedings. The fecal consistency was also a significant looser the egg yolk lecithin (-) group than the egg yolk lecithin (+) groups from day 4 of test meal feeding. The fecal consistency was no significant difference between the medium-chain triglycerides (-) and egg yolk lecithin (+) groups. Enteral formula emulsified with egg yolk lecithin promotes lipid absorption by preventing the destruction of emulsified substances by gastric acid. This enteral formula improved diarrhea and should reduce the burden on patients and healthcare workers.

  12. Live imaging of apoptotic cells in zebrafish

    PubMed Central

    van Ham, Tjakko J.; Mapes, James; Kokel, David; Peterson, Randall T.

    2010-01-01

    Many debilitating diseases, including neurodegenerative diseases, involve apoptosis. Several methods have been developed for visualizing apoptotic cells in vitro or in fixed tissues, but few tools are available for visualizing apoptotic cells in live animals. Here we describe a genetically encoded fluorescent reporter protein that labels apoptotic cells in live zebrafish embryos. During apoptosis, the phospholipid phosphatidylserine (PS) is exposed on the outer leaflet of the plasma membrane. The calcium-dependent protein Annexin V (A5) binds PS with high affinity, and biochemically purified, fluorescently labeled A5 probes have been widely used to detect apoptosis in vitro. Here we show that secreted A5 fused to yellow fluorescent protein specifically labels apoptotic cells in living zebrafish. We use this fluorescent probe to characterize patterns of apoptosis in living zebrafish larvae and to visualize neuronal cell death at single-cell resolution in vivo.—Van Ham, T. J., Mapes, J., Kokel, D., Peterson, R. T. Live imaging of apoptotic cells in zebrafish. PMID:20601526

  13. Primary yolk sac tumor of the urachus.

    PubMed

    Romero-Rojas, Alfredo Ernesto; Messa-Botero, Oscar Alberto; Melo-Uribe, Mario Alexander; Díaz-Pérez, Julio Alexander; Chinchilla-Olaya, Sandra Isabel

    2011-10-01

    Neoplasms originating from the urachus are rare. The most common urachal malignancy is adenocarcinoma, whereas extragonadal germ cell tumors, primarily of the urachus, are an extremely rare finding. To describe a primary yolk sac tumor (YST) of the urachus in an adult. A 44-year-old woman presented with 6 months of pelvic pain associated with a sensation of progressive mass growth. At the time of tumor resection, the tumor was found to be attached by a pedicle to the dome of the bladder, with no injury to the adjacent organs. Pathological study showed a neoplasm with epithelioid cells, pseudocysts, a myxomatous background, and Schiller-Duval body formations. Immunohistochemistry stains showed positivity to AE1/AE3, α-1-fetoprotein, and α-1-antitrypsin and negativity to other markers. An unusual case of a YST in the urachus is presented. This is the first reported adult case based on the authors' bibliographic search.

  14. Dynamics of a suspension of interacting yolk-shell particles

    DOE PAGES

    Sánchez Díaz, L. E.; Cortes-Morales, E. C.; Li, X.; ...

    2014-12-01

    In this work we study the self-diusion properties of a liquid of hollow spherical particles (shells) bearing a smaller solid sphere in their interior (yolks). We model this system using purely repulsive hard-body interactions between all (shell and yolk) particles, but assume the presence of a background ideal solvent such that all the particles execute free Brownian motion between collisions, characterized by short-time self-diusion coecients D0 s for the shells and D0 y for the yolks. Using a softened version of these interparticle potentials we perform Brownian dynamics simulations to determine the mean squared displacement and intermediate scattering function ofmore » the yolk-shell complex. These results can be understood in terms of a set of eective Langevin equations for the N interacting shell particles, pre-averaged over the yolks' degrees of freedom, from which an approximate self-consistent description of the simulated self-diusion properties can be derived. Here we compare the theoretical and simulated results between them, and with the results for the same system in the absence of yolks. We nd that the yolks, which have no eect on the shell-shell static structure, in uence the dynamic properties in a predictable manner, fully captured by the theory.« less

  15. A simplified method for extracting androgens from avian egg yolks

    Kozlowski, C.P.; Bauman, J.E.; Hahn, D.C.

    2009-01-01

    Female birds deposit significant amounts of steroid hormones into the yolks of their eggs. Studies have demonstrated that these hormones, particularly androgens, affect nestling growth and development. In order to measure androgen concentrations in avian egg yolks, most authors follow the extraction methods outlined by Schwabl (1993. Proc. Nat. Acad. Sci. USA 90:11446-11450). We describe a simplified method for extracting androgens from avian egg yolks. Our method, which has been validated through recovery and linearity experiments, consists of a single ethanol precipitation that produces substantially higher recoveries than those reported by Schwabl.

  16. [Application of asymmetrical flow field-flow fractionation for size characterization of low density lipoprotein in egg yolk plasma].

    PubMed

    Zhang, Wenhui; Cai, Chunxue; Wang, Jing; Mao, Zhen; Li, Yueqiu; Ding, Liang; Shen, Shigang; Dou, Haiyang

    2017-08-08

    Home-made asymmetrical flow field-flow fractionation (AF4) system, online coupled with ultraviolet/visible (UV/Vis) detector was employed for the separation and size characterization of low density lipoprotein (LDL) in egg yolk plasma. At close to natural condition of egg yolk, the effects of cross flow rate, sample loading, and type of membrane on the size distribution of LDL were investigated. Under the optimal operation conditions, AF4-UV/Vis provides the size distribution of LDL. Moreover, the precision of AF4-UV/Vis method proposed in this work for the analysis of LDL in egg yolk plasma was evaluated. The intra-day precisions were 1.3% and 1.9% ( n =7) and the inter-day precisions were 2.4% and 2.3% ( n =7) for the elution peak height and elution peak area of LDL, respectively. Results reveal that AF4-UV/Vis is a useful tool for the separation and size characterization of LDL in egg yolk plasma.

  17. Zebrafish Health Conditions in the China Zebrafish Resource Center and 20 Major Chinese Zebrafish Laboratories.

    PubMed

    Liu, Liyue; Pan, Luyuan; Li, Kuoyu; Zhang, Yun; Zhu, Zuoyan; Sun, Yonghua

    2016-07-01

    In China, the use of zebrafish as an experimental animal in the past 15 years has widely expanded. The China Zebrafish Resource Center (CZRC), which was established in 2012, is becoming one of the major resource centers in the global zebrafish community. Large-scale use and regular exchange of zebrafish resources have put forward higher requirements on zebrafish health issues in China. This article reports the current aquatic infrastructure design, animal husbandry, and health-monitoring programs in the CZRC. Meanwhile, through a survey of 20 Chinese zebrafish laboratories, we also describe the current health status of major zebrafish facilities in China. We conclude that it is of great importance to establish a widely accepted health standard and health-monitoring strategy in the Chinese zebrafish research community.

  18. Teratological Effects of a Panel of Sixty Water-Soluble Toxicants on Zebrafish Development

    PubMed Central

    Ali, Shaukat; Aalders, Jeffrey

    2014-01-01

    Abstract The zebrafish larva is a promising whole-animal model for safety pharmacology, environmental risk assessment, and developmental toxicity. This model has been used for the high-throughput toxicity screening of various compounds. Our aim here is to identify possible phenotypic markers of teratogenicity in zebrafish embryos that could be used for the assaying compounds for reproductive toxicity. We have screened a panel of 60 water-soluble toxicants to examine their effects on zebrafish development. A total of 22,080 wild-type zebrafish larvae were raised in 250 μL defined buffer in 96-well plates at a plating density of one embryo per well. They were exposed for a 96-h period starting at 24 h post-fertilization. A logarithmic concentration series was used for range-finding, followed by a narrower geometric series for developmental toxicity assessment. A total of 9017 survivors were analyzed at 5 days post-fertilization for nine phenotypes, namely, (1) normal, (2) pericardial oedema, (3) yolk sac oedema, (4) melanophores dispersed, (5) bent tail tip, (6) bent body axis, (7) abnormal Meckel's cartilage, (8) abnormal branchial arches, and (9) uninflated swim bladder. For each toxicant, the EC50 (concentration required to produce one or more of these abnormalities in 50% of embryos) was also calculated. For the majority of toxicants (55/60) there was, at the population level, a statistically significant, concentration-dependent increase in the incidence of abnormal phenotypes among survivors. The commonest abnormalities were pericardial oedema, yolk sac oedema, dispersed melanophores, and uninflated swim bladder. It is possible therefore that these could prove to be general indicators of reproductive toxicity in the zebrafish embryo assay. PMID:24650241

  19. Impact of CdSe/ZnS quantum dots on the development of zebrafish embryos

    NASA Astrophysics Data System (ADS)

    Lei, Yong; Xiao, Qi; Huang, Shan; Xu, Wansu; Zhang, Zhe; He, Zhike; Liu, Yi; Deng, Fengjiao

    2011-12-01

    Due to their unique fluorescent characteristics, quantum dots (QDs) have been successfully applied in the fields of biotechnology and medicine, but there is very limited information regarding their biodistribution and chronic toxicity in vivo. In this article, the biological behavior and toxic effects of mercaptoacetic acid-CdSe/ZnS QDs (MAA-QDs) in developing zebrafish embryos were investigated by in vivo tests. The MAA-QDs were introduced into zebrafish through microinjection at early stage. The results showed that the MAA-QDs at certain concentrations influenced the survival of zebrafish embryos, but treated embryos without developmental defects were also observed. MAA-QDs injected into the cytoplasm at the one-cell stage were allocated to progeny blastoderm cells during proliferation and almost never entered the yolk. The formation of notochord and primordial germ cells with normal morphologies was detected in the treated embryos by whole-mount in situ hybridization. Furthermore, traces of the element cadmium were mainly discovered in the tissue of liver and kidney of 3-month-old-treated zebrafish by quantitative assessment with inductively coupled plasma mass spectrometry. Thus, we hypothesized that low concentration MAA-QDs have chronic toxicities when they were delivered into zebrafish organs.

  20. Soft template synthesis of yolk/silica shell particles.

    PubMed

    Wu, Xue-Jun; Xu, Dongsheng

    2010-04-06

    Yolk/shell particles possess a unique structure that is composed of hollow shells that encapsulate other particles but with an interstitial space between them. These structures are different from core/shell particles in that the core particles are freely movable in the shell. Yolk/shell particles combine the properties of each component, and can find potential applications in catalysis, lithium ion batteries, and biosensors. In this Research News article, a soft-template-assisted method for the preparation of yolk/silica shell particles is presented. The demonstrated method is simple and general, and can produce hollow silica spheres incorporated with different particles independent of their diameters, geometry, and composition. Furthermore, yolk/mesoporous silica shell particles and multishelled particles are also prepared through optimization of the experimental conditions. Finally, potential applications of these particles are discussed.

  1. Zebrafish and Streptococcal Infections.

    PubMed

    Saralahti, A; Rämet, M

    2015-09-01

    Streptococcal bacteria are a versatile group of gram-positive bacteria capable of infecting several host organisms, including humans and fish. Streptococcal species are common colonizers of the human respiratory and gastrointestinal tract, but they also cause some of the most common life-threatening, invasive infections in humans and aquaculture. With its unique characteristics and efficient tools for genetic and imaging applications, the zebrafish (Danio rerio) has emerged as a powerful vertebrate model for infectious diseases. Several zebrafish models introduced so far have shown that zebrafish are suitable models for both zoonotic and human-specific infections. Recently, several zebrafish models mimicking human streptococcal infections have also been developed. These models show great potential in providing novel information about the pathogenic mechanisms and host responses associated with human streptococcal infections. Here, we review the zebrafish infection models for the most relevant streptococcal species: the human-specific Streptococcus pneumoniae and Streptococcus pyogenes, and the zoonotic Streptococcus iniae and Streptococcus agalactiae. The recent success and the future potential of these models for the study of host-pathogen interactions in streptococcal infections are also discussed. © 2015 The Foundation for the Scandinavian Journal of Immunology.

  2. Measuring zebrafish turning rate.

    PubMed

    Mwaffo, Violet; Butail, Sachit; di Bernardo, Mario; Porfiri, Maurizio

    2015-06-01

    Zebrafish is becoming a popular animal model in preclinical research, and zebrafish turning rate has been proposed for the analysis of activity in several domains. The turning rate is often estimated from the trajectory of the fish centroid that is output by commercial or custom-made target tracking software run on overhead videos of fish swimming. However, the accuracy of such indirect methods with respect to the turning rate associated with changes in heading during zebrafish locomotion is largely untested. Here, we compare two indirect methods for the turning rate estimation using the centroid velocity or position data, with full shape tracking for three different video sampling rates. We use tracking data from the overhead video recorded at 60, 30, and 15 frames per second of zebrafish swimming in a shallow water tank. Statistical comparisons of absolute turning rate across methods and sampling rates indicate that, while indirect methods are indistinguishable from full shape tracking, the video sampling rate significantly influences the turning rate measurement. The results of this study can aid in the selection of the video capture frame rate, an experimental design parameter in zebrafish behavioral experiments where activity is an important measure.

  3. Distribution of sulfamonomethoxine and trimethoprim in egg yolk and white.

    PubMed

    Bilandžić, Nina; Božić, Đurđica; Kolanović, Božica Solomun; Varenina, Ivana; Cvetnić, Luka; Cvetnić, Željko

    2015-07-01

    The distribution of sulfamonomethoxine (SMM) and trimethoprim (TMP) in egg yolk and white was measured during and after administration of a SMM/TMP combination in laying hens in doses of 8 g l(-)(1) and 12 g l(-)(1) in drinking water for 7 days. The SMM concentration reached maximal levels on day 2 of the post-treatment period for both doses (μg kg(-)(1)): 5920 and 9453 in yolk; 4831 and 6050 in white, in doses 1 and 2, respectively. Significant differences in the SMM and TMP concentrations between yolk and white in post treatment period were found. SMM dropped below the LOD (1.9 μg kg(-1)) in yolk after day 16 and 19 for doses 1 and 2. TMP reached maximal levels on day 3 after drug administration for doses 1 and 2 (μg kg(-)(1)): 6521 and 7329 in yolk, 1370 and 1539 in white. TMP residues were measured above LOD (0.3 μg kg(-)(1)) in yolk for both doses on day 37 post-treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Quantification of Estradiol Uptake in Zebrafish Embryos and Larvae.

    PubMed

    Souder, Jaclyn Paige; Gorelick, Daniel A

    2017-08-01

    Zebrafish are a powerful model system to assess the molecular and cellular effects of exposure to toxic chemicals during embryonic development. To study the effects of environmental endocrine disruptors, embryos and larvae are commonly exposed to supraphysiologic concentrations of these compounds in the water, but their bioavailability in zebrafish is largely unknown. One hypothesis is that supraphysiologic concentrations of estrogens in the water are required to achieve physiologic levels in vivo; however, this has not been directly tested. To test this hypothesis, we developed an assay using radiolabeled estradiol ([3H]E2) to measure uptake from water at multiple concentrations and exposure durations in developing zebrafish from 0 to 5 days postfertilization (dpf). We found that [3H]E2 uptake increased with increasing concentration, duration, and developmental stage. Percent uptake from the total volume of treatment solution increased with increasing exposure duration and developmental stage, but remained constant with increasing concentration. We also found that the chorion, an acellular envelope surrounding embryos through 3 dpf, did not substantially affect [3H]E2 uptake. Finally, we found that at 1 dpf, E2 was preferentially taken up by the yolk at multiple exposure durations, while at 2 dpf E2 was preferentially taken up into the embryonic body. Our results support the hypothesis that exposing zebrafish embryos and larvae to supraphysiologic concentrations of estrogens is required to achieve physiologically relevant doses in vivo. The isotopic assay reported here will provide a foundation for determining the uptake of other compounds for teratogenicity, toxicology and drug discovery studies. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  5. Toxicity of silver nanoparticles in zebrafish models

    NASA Astrophysics Data System (ADS)

    Asharani, P. V.; Lian Wu, Yi; Gong, Zhiyuan; Valiyaveettil, Suresh

    2008-06-01

    This study was initiated to enhance our insight on the health and environmental impact of silver nanoparticles (Ag-np). Using starch and bovine serum albumin (BSA) as capping agents, silver nanoparticles were synthesized to study their deleterious effects and distribution pattern in zebrafish embryos (Danio rerio). Toxicological endpoints like mortality, hatching, pericardial edema and heart rate were recorded. A concentration-dependent increase in mortality and hatching delay was observed in Ag-np treated embryos. Additionally, nanoparticle treatments resulted in concentration-dependent toxicity, typified by phenotypes that had abnormal body axes, twisted notochord, slow blood flow, pericardial edema and cardiac arrhythmia. Ag+ ions and stabilizing agents showed no significant defects in developing embryos. Transmission electron microscopy (TEM) of the embryos demonstrated that nanoparticles were distributed in the brain, heart, yolk and blood of embryos as evident from the electron-dispersive x-ray analysis (EDS). Furthermore, the acridine orange staining showed an increased apoptosis in Ag-np treated embryos. These results suggest that silver nanoparticles induce a dose-dependent toxicity in embryos, which hinders normal development.

  6. Comparative proteome analysis of egg yolk plasma proteins during storage.

    PubMed

    Gao, Dan; Qiu, Ning; Liu, Yaping; Ma, Meihu

    2017-06-01

    Physical changes such as chicken egg white thinning and egg yolk flattening occur during storage, implying a decline in egg quality. To reveal the deteriorative process related to chicken egg internal quality, a comparative proteomic method was used in this study to analyze the alterations in egg yolk plasma proteins at different storage times (0, 20 and 40 days) under an ambient temperature of 22 ± 2 °C. Using two-dimensional electrophoresis followed by matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry, 33 protein spots representing 12 proteins were identified with significant (P < 0.05) alterations in abundance at different storage times. The proteins that showed significant changes in abundance included serum albumin, vitellogenin fragments, IgY chains, ovalbumin, ovoinhibitor, α 2 -macroglobulin-like protein 1-like, hemopexin, transthyretin, apolipoprotein A-I and β 2 -glycoprotein I precursor. Accelerating degradation for most egg yolk plasma proteins was observed after prolonged storage (from day 20 to day 40). It is likely that the increased degradation of protease inhibitors such as ovoinhibitor and α 2 -macroglobulin-like protein 1-like during prolonged storage lead to an imbalance of protease and antiprotease in egg yolk, which may play a key role in the degradation of egg yolk proteins. These findings will provide an insight into the effects of storage on egg yolk protein changes and give a deeper understanding of the deteriorative process of chicken egg yolk. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  7. Toxicological and behavioral responses as a tool to assess the effects of natural and synthetic dyes on zebrafish early life.

    PubMed

    Abe, Flavia R; Mendonça, Jacqueline N; Moraes, Luiz A B; Oliveira, Gisele A R de; Gravato, Carlos; Soares, Amadeu M V M; Oliveira, Danielle P de

    2017-07-01

    Organic dyes extracted from natural sources have been widely used to develop safety and eco-friendly dyes as an alternative to synthetic ones, since the latter are usually precursors of mutagenic compounds. Thereby, toxicity tests to non-target organisms are critical step to develop harmless dyes to environment and in this context, zebrafish early life stages are becoming an important alternative model. We aimed to assess the toxic effects of the synthetic dye Basic Red 51 (BR51, used in cosmetic industry), the natural dye erythrostominone (ERY, a potential commercial dye extracted from fungi) and its photodegradation product (DERY), using zebrafish early life assays. Developmental malformations on embryos and behavioral impairment on larvae were explored. Our results showed that embryos exposed to BR51 and ERY exhibited a large yolk sac (LOEC = 7.5 mg L -1 ), possibly due to a deformity or delayed resorption. ERY also induced pericardial and yolk sac edemas at high concentrations (LOEC = 15 and 30 mg L -1 , respectively). Moreover, larvae swan less distance and time when exposed to ERY (LOEC = 7.5 mg L -1 ) and BR51 (LOEC = 1.875 mg L -1 ). The lowest larvae locomotion have been associated with impairment of the yolk sac, important tissue of the energy source. Interestingly, DERY did not affect neither development nor behavior of zebrafish, showing that ERY photodegradation is sufficient to prevent its toxic effects. In conclusion, both natural and synthetic dyes impaired development and behavior of zebrafish early life, therefore, a simple treatment of the natural dye can prevent the aquatic life impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Yolk Sac Mesenchymal Progenitor Cells from New World Mice (Necromys lasiurus) with Multipotent Differential Potential

    PubMed Central

    Favaron, Phelipe Oliveira; Mess, Andrea; Will, Sônia Elisabete; Maiorka, Paulo César; de Oliveira, Moacir Franco; Miglino, Maria Angelica

    2014-01-01

    Fetal membranes are abundant, ethically acceptable and readily accessible sources of stem cells. In particular, the yolk sac is a source of cell lineages that do not express MHCs and are mainly free from immunological incompatibles when transferred to a recipient. Although data are available especially for hematopoietic stem cells in mice and human, whereas other cell types and species are dramatically underrepresented. Here we studied the nature and differentiation potential of yolk sac derived mesenchymal stem cells from a New World mouse, Necromys lasiurus. Explants from mid-gestation were cultured in DMEM-High glucose medium with 10% defined fetal bovine serum. The cells were characterized by standard methods including immunophenotyping by fluorescence and flow cytometry, growth and differentiation potential and tumorigenicity assays. The first adherent cells were observed after 7 days of cell culture and included small, elongated fibroblast-like cells (92.13%) and large, round epithelial-like cells with centrally located nuclei (6.5%). Only the fibroblast-like cells survived the first passages. They were positive to markers for mesenchymal stem cells (Stro-1, CD90, CD105, CD73) and pluripotency (Oct3/4, Nanog) as well as precursors of hematopoietic stem cells (CD117). In differentiation assays, they were classified as a multipotent lineage, because they differentiated into osteogenic, adipogenic, and chondrogenic lineages and, finally, they did not develop tumors. In conclusion, mesenchymal progenitor cells with multipotent differentiation potential and sufficient growth and proliferation abilities were able to be obtained from Necromys yolk sacs, therefore, we inferred that these cells may be promising for a wide range of applications in regenerative medicine. PMID:24918429

  9. An Extensive Description of the Peptidomic Repertoire of the Hen Egg Yolk Plasma.

    PubMed

    Arena, Simona; Scaloni, Andrea

    2018-03-28

    Hen egg is a raw material widely used for the preparation of food,  pharmaceutical and cosmetoceutical products. Dedicated proteomic studies were accomplished on eggshell membrane, egg white, and yolk, identifying the most abundant proteins. No similar peptidomic studies have been performed so far. Only preliminary investigations on bioactive peptides in egg fractions and digestates were accomplished through functional screening assays, characterizing antioxidant, antibacterial, antiviral, immunomodulatory, and antihypertensive preparations and isolated components. This study fills this gap and provides a comprehensive picture of the peptides present in the yolk plasma of different hen egg types after 24 and 264 h of laying, taking advantage of a procedure based on a two-step fractionation followed by combined MALDI-TOF-TOF-MS- and nanoLC-ESI-Q-Orbitrap-MS/MS-based analysis. Six hundred and twenty-eight peptides were characterized as deriving from the proteolytic processing of larger protein components after the physiological action of chicken chymotrypsin-like and pepsin-like enzymes. Structural details on their post-translational modifications were also provided. Identified peptides were subjected to bioinformatic analysis and further compared with available data from the literature, ascertaining 198 peptides associable with putative antihypertensive, antimicrobial, anticancer, antiviral, antibiofilm, anorectic, calcium-binding, and anti-inflammatory activities. This analysis was often confirmative of previous experimental evidence on functional properties of unfractionated preparations or isolated molecules. These results further emphasize the bioactive action of yolk-derived peptides as related to egg consumption, and the potential use of these molecules as additive ingredients in the preparation of functional foods and cosmetics.

  10. Effect of domestic cooking methods on egg yolk xanthophylls.

    PubMed

    Nimalaratne, Chamila; Lopes-Lutz, Daise; Schieber, Andreas; Wu, Jianping

    2012-12-26

    Xanthophylls are a class of bioactive compounds known to play an important role in preventing age-related macular degeneration. Egg yolk is a rich source of highly bioavailable xanthophylls including lutein and zeaxanthin. The effects of domestic cooking methods (boiling, frying, microwaving) on egg yolk xanthophyll content were investigated. A LC-(APCI)-MS/MS method was used to identify and quantify all-E- and Z-isomers of lutein, zeaxanthin, canthaxanthin, and β-apo-8'-carotenoic acid ethyl ester in fresh and cooked egg yolks. Both fresh and cooked yolks showed similar xanthophyll profiles but with higher contents of Z-isomers in cooked samples. All-E-lutein was the most affected, with 22.5%, 16.7%, and 19.3% reductions in boiled, microwaved, and fried yolk extracts, respectively. Total xanthophyll losses ranged from 6% to 18%. The results presented here could be useful in calculating the dietary intake of xanthophylls and also in assessing the xanthophyll profiles and contents of egg-containing products.

  11. Mycobacteriosis in zebrafish colonies.

    PubMed

    Whipps, Christopher M; Lieggi, Christine; Wagner, Robert

    2012-01-01

    Mycobacteriosis, a chronic bacterial infection, has been associated with severe losses in some zebrafish facilities and low-level mortalities and unknown impacts in others. The occurrence of at least six different described species (Mycobacterium abscessus, M. chelonae, M. fortuitum, M. haemophilum, M. marinum, M. peregrinum) from zebrafish complicates diagnosis and control because each species is unique. As a generalization, mycobacteria are often considered opportunists, but M. haemophilum and M. marinum appear to be more virulent. Background genetics of zebrafish and environmental conditions influence the susceptibility of fish and progression of disease, emphasizing the importance of regular monitoring and good husbandry practices. A combined approach to diagnostics is ultimately the most informative, with histology as a first-level screen, polymerase chain reaction for rapid detection and species identification, and culture for strain differentiation. Occurrence of identical strains of Mycobacterium in both fish and biofilms in zebrafish systems suggests transmission can occur when fish feed on infected tissues or tank detritus containing mycobacteria. Within a facility, good husbandry practices and sentinel programs are essential for minimizing the impacts of mycobacteria. In addition, quarantine and screening of animals coming into a facility is important for eliminating the introduction of the more severe pathogens. Elimination of mycobacteria from an aquatic system is likely not feasible because these species readily establish biofilms on surfaces even in extremely low nutrient conditions. Risks associated with each commonly encountered species need to be identified and informed management plans developed. Basic research on the growth characteristics, disinfection, and pathogenesis of zebrafish mycobacteria is critical moving forward.

  12. Anesthesia and euthanasia in zebrafish.

    PubMed

    Matthews, Monte; Varga, Zoltán M

    2012-01-01

    Because of the relative ease of embryonic manipulation and observation, the ability to produce a great number of genetic mutations, efficient screening methods, and the continued advance of molecular genetic tools, such as the progress in sequencing and mapping of the zebrafish genome, the use of zebrafish (Danio rerio) as a biomedical model organism continues to expand. However, studies involving zebrafish husbandry and veterinary care struggle to keep pace with scientific progress. This article outlines some of the current, acceptable methods for providing anesthesia and euthanasia and provides some examples of how performance-based approaches can be used to advance the relatively limited number of anesthetic and euthanizing techniques available for zebrafish.

  13. Does dietary vitamin E or C decrease egg yolk cholesterol?

    PubMed

    Mohiti-Asli, Maziar; Zaghari, Mojtaba

    2010-12-01

    An experiment was conducted to determine the effect of dietary vitamin E and C on serum metabolites, yolk cholesterol, egg quality, and performance of layer hens. One hundred sixty-eight commercial Hy-Line W-36 layer hens were randomly divided into seven groups and six replicates with four hens in each. Dietary treatments were introduced after the pre-experimental period (10 days) to adjust egg production. Treatments were levels of vitamin E or C (100, 200, and 400 mg/kg diet) supplementation to the basal diet for 4 weeks, whereas the control group received no supplementation. Egg production, egg weight, and feed consumption were recorded during the study. Shell thickness, Haugh unit score, yolk color, yolk weight, yolk cholesterol, and blood parameters were measured at the end of experiment. There was no significant effect of dietary vitamin E or C on hen performance. Egg yolk cholesterol concentrations decreased linearly by antioxidant vitamin supplementation (P < 0.01). Egg yolk cholesterol reduction did not have any negative effect on egg production rate. Antioxidants, especially vitamin C, increased serum glucose concentration (P < 0.05). Serum total cholesterol content did not change by vitamin supplementation but cholesterol in high-density lipoprotein (HDL-C) decreased and cholesterol in low-density lipoprotein (LDL-C) increased (P < 0.05), as dietary vitamin E or C supplementation increased in diets. These results are in conflict with the previous hypothesis that antioxidants have a role in LDL-C removal from the blood or increasing HDL-C. Vitamin E was more effective than vitamin C in this case and if these results are confirmed by further studies, they may result to revision in researchers' point of view about antioxidant especially in human medicine.

  14. Calcium- and polyphosphate-containing acidocalcisomes in chicken egg yolk.

    PubMed

    Ramos, Isabela B; Miranda, Kildare; Ulrich, Paul; Ingram, Peter; LeFurgey, Ann; Machado, Ednildo A; de Souza, Wanderley; Docampo, Roberto

    2010-04-09

    Poly P (inorganic polyphosphate) is a polymer formed by P(i) residues linked by high-energy phosphoanhydride bonds. The presence of poly P in bacteria, fungi, algae and protists has been widely recognized, but the distribution of poly P in more complex eukaryotes has been poorly studied. Poly P accumulates, together with calcium, in acidic vesicles or acidocalcisomes in a number of organisms and possesses a diverse array of functions, including roles in stress response, blood clotting, inflammation, calcification, cell proliferation and apoptosis. We report here that a considerable amount of phosphorus in the yolk of chicken eggs is in the form of poly P. DAPI (4',6-diamidino-2-phenylindole) staining showed that poly P is localized mainly in electron-dense vesicles located inside larger vacuoles (compound organelles) that are randomly distributed in the yolk. These internal vesicles were shown to contain calcium, potassium, sodium, magnesium, phosphorus, chlorine, iron and zinc, as detected by X-ray microanalysis and elemental mapping. These vesicles stain with the acidophilic dye Acridine Orange. The presence of poly P in organellar fractions of the egg yolk was evident in agarose gels stained with Toluidine Blue and DAPI. Of the total phosphate (Pi) of yolk organelles, 16% is present in the form of poly P. Total poly P content was not altered during the first 4 days of embryogenesis, but poly P chain length decreased after 1 day of development. The results of the present study identify a novel organelle in chicken egg yolk comprising acidic vesicles with a morphology, physiology and composition similar to those of acidocalcisomes, within larger acidic vacuoles. The elemental composition of these acidocalcisomes is proportionally similar to the elemental composition of the yolk, suggesting that most of these elements are located in these organelles, which might be an important storage compartment in eggs.

  15. Loss of PiT-1 Results in Abnormal Endocytosis in the Yolk Sac Visceral Endoderm

    PubMed Central

    Wallingford, Mary C.; Giachelli, Cecilia M.

    2014-01-01

    PiT-1 protein is a transmembrane sodium-dependent phosphate (Pi) transporter. PiT-1 knock out (KO) embryos die from largely unknown causes by embryonic day (E) 12.5. We tested the hypothesis that PiT-1 is required for endocytosis in the embryonic yolk sac (YS) visceral endoderm (VE). Here we present data supporting that PiT-1 KO results in a YS remodeling defect and decreased endocytosis in the YS VE. The remodeling defect is not due to an upstream cardiomyocyte requirement for PiT-1, as SM22αCre-specific KO of PiT-1 in the developing heart and the YS mesodermal layer (ME) does not recapitulate the PiT-1 global KO phenotype. Furthermore, we find that high levels of PiT-1 protein localize to the YS VE apical membrane. Together these data support that PiT-1 is likely required in YS VE. During normal development maternal immunoglobulin (IgG) is endocytosed into YS VE and accumulates in the apical side of the VE in a specialized lysosome termed the apical vacuole (AV). We have identified a reduction in PiT-1 KO VE cell height and a striking loss of IgG accumulation in the PiT-1 KO VE. The endocytosis genes Tfeb, Lamtor2 and Snx2 are increased at the RNA level. Lysotracker Red staining reveals a loss of distinct AVs, and yolk sacs incubated ex vivo with phRODO Green Dextran for Endocytosis demonstrate a functional loss of endocytosis. As yolk sac endocytosis is controlled in part by microautophagy, but expression of LC3 had not been examined, we investigated LC3 expression during yolk sac development and found stage-specific LC3 RNA expression that is predominantly from the YS VE layer at E9.5. Normalized LC3-II protein levels are decreased in the PiT-1 KO YS, supporting a requirement for PiT-1 in autophagy in the YS. Therefore, we propose the novel idea that PiT-1 is central to the regulation of endocytosis and autophagy in the YS VE. PMID:25138534

  16. Toxic Effects of Silica Nanoparticles on Zebrafish Embryos and Larvae

    PubMed Central

    Shi, Huiqin; Tian, Linwei; Guo, Caixia; Huang, Peili; Zhou, Xianqing; Peng, Shuangqing; Sun, Zhiwei

    2013-01-01

    Silica nanoparticles (SiNPs) have been widely used in biomedical and biotechnological applications. Environmental exposure to nanomaterials is inevitable as they become part of our daily life. Therefore, it is necessary to investigate the possible toxic effects of SiNPs exposure. In this study, zebrafish embryos were treated with SiNPs (25, 50, 100, 200 µg/mL) during 4–96 hours post fertilization (hpf). Mortality, hatching rate, malformation and whole-embryo cellular death were detected. We also measured the larval behavior to analyze whether SiNPs had adverse effects on larvae locomotor activity. The results showed that as the exposure dosages increasing, the hatching rate of zebrafish embryos was decreased while the mortality and cell death were increased. Exposure to SiNPs caused embryonic malformations, including pericardial edema, yolk sac edema, tail and head malformation. The larval behavior testing showed that the total swimming distance was decreased in a dose-dependent manner. The lower dose (25 and 50 µg/mL SiNPs) produced substantial hyperactivity while the higher doses (100 and 200 µg/mL SiNPs) elicited remarkably hypoactivity in dark periods. In summary, our data indicated that SiNPs caused embryonic developmental toxicity, resulted in persistent effects on larval behavior. PMID:24058598

  17. Effect of hen's egg yolk on capacitation and acrosome reaction of diluted canine spermatozoa.

    PubMed

    Witte, T S; Schäfer-Somi, S; Kuchar, A; Möstl, E; Iben, C; Aurich, C

    2009-02-01

    membranes decreased significantly (p<0.05) and capacitated spermatozoa increased (p<0.05), which was not seen in TCF-EY-samples. In all samples, low percentages of AR were detected and after 4 days, the highest value of AR in TCF-EY-samples was 5.3% on average, as detected by flow cytometry. We therefore conclude that progesterone from egg yolk in routine extenders does not substantially influence semen longevity or AR of canine semen during cold-storage for 4 days. In contrary, egg yolk seems to prevent a significant increase in capacitated spermatozoa.

  18. The multivariate egg: quantifying within- and among-clutch correlations between maternally derived yolk immunoglobulins and yolk androgens using multivariate mixed models.

    PubMed

    Postma, Erik; Siitari, Heli; Schwabl, Hubert; Richner, Heinz; Tschirren, Barbara

    2014-03-01

    Egg components are important mediators of prenatal maternal effects in birds and other oviparous species. Because different egg components can have opposite effects on offspring phenotype, selection is expected to favour their mutual adjustment, resulting in a significant covariation between egg components within and/or among clutches. Here we tested for such correlations between maternally derived yolk immunoglobulins and yolk androgens in great tit (Parus major) eggs using a multivariate mixed-model approach. We found no association between yolk immunoglobulins and yolk androgens within clutches, indicating that within clutches the two egg components are deposited independently. Across clutches, however, there was a significant negative relationship between yolk immunoglobulins and yolk androgens, suggesting that selection has co-adjusted their deposition. Furthermore, an experimental manipulation of ectoparasite load affected patterns of covariance among egg components. Yolk immunoglobulins are known to play an important role in nestling immune defence shortly after hatching, whereas yolk androgens, although having growth-enhancing effects under many environmental conditions, can be immunosuppressive. We therefore speculate that variation in the risk of parasitism may play an important role in shaping optimal egg composition and may lead to the observed pattern of yolk immunoglobulin and yolk androgen deposition across clutches. More generally, our case study exemplifies how multivariate mixed-model methodology presents a flexible tool to not only quantify, but also test patterns of (co)variation across different organisational levels and environments, allowing for powerful hypothesis testing in ecophysiology.

  19. Flat mount preparation for observation and analysis of zebrafish embryo specimens stained by whole mount in situ hybridization.

    PubMed

    Cheng, Christina N; Li, Yue; Marra, Amanda N; Verdun, Valerie; Wingert, Rebecca A

    2014-07-17

    The zebrafish embryo is now commonly used for basic and biomedical research to investigate the genetic control of developmental processes and to model congenital abnormalities. During the first day of life, the zebrafish embryo progresses through many developmental stages including fertilization, cleavage, gastrulation, segmentation, and the organogenesis of structures such as the kidney, heart, and central nervous system. The anatomy of a young zebrafish embryo presents several challenges for the visualization and analysis of the tissues involved in many of these events because the embryo develops in association with a round yolk mass. Thus, for accurate analysis and imaging of experimental phenotypes in fixed embryonic specimens between the tailbud and 20 somite stage (10 and 19 hours post fertilization (hpf), respectively), such as those stained using whole mount in situ hybridization (WISH), it is often desirable to remove the embryo from the yolk ball and to position it flat on a glass slide. However, performing a flat mount procedure can be tedious. Therefore, successful and efficient flat mount preparation is greatly facilitated through the visual demonstration of the dissection technique, and also helped by using reagents that assist in optimal tissue handling. Here, we provide our WISH protocol for one or two-color detection of gene expression in the zebrafish embryo, and demonstrate how the flat mounting procedure can be performed on this example of a stained fixed specimen. This flat mounting protocol is broadly applicable to the study of many embryonic structures that emerge during early zebrafish development, and can be implemented in conjunction with other staining methods performed on fixed embryo samples.

  20. Flat Mount Preparation for Observation and Analysis of Zebrafish Embryo Specimens Stained by Whole Mount In situ Hybridization

    PubMed Central

    Cheng, Christina N.; Li, Yue; Marra, Amanda N.; Verdun, Valerie; Wingert, Rebecca A.

    2014-01-01

    The zebrafish embryo is now commonly used for basic and biomedical research to investigate the genetic control of developmental processes and to model congenital abnormalities. During the first day of life, the zebrafish embryo progresses through many developmental stages including fertilization, cleavage, gastrulation, segmentation, and the organogenesis of structures such as the kidney, heart, and central nervous system. The anatomy of a young zebrafish embryo presents several challenges for the visualization and analysis of the tissues involved in many of these events because the embryo develops in association with a round yolk mass. Thus, for accurate analysis and imaging of experimental phenotypes in fixed embryonic specimens between the tailbud and 20 somite stage (10 and 19 hours post fertilization (hpf), respectively), such as those stained using whole mount in situ hybridization (WISH), it is often desirable to remove the embryo from the yolk ball and to position it flat on a glass slide. However, performing a flat mount procedure can be tedious. Therefore, successful and efficient flat mount preparation is greatly facilitated through the visual demonstration of the dissection technique, and also helped by using reagents that assist in optimal tissue handling. Here, we provide our WISH protocol for one or two-color detection of gene expression in the zebrafish embryo, and demonstrate how the flat mounting procedure can be performed on this example of a stained fixed specimen. This flat mounting protocol is broadly applicable to the study of many embryonic structures that emerge during early zebrafish development, and can be implemented in conjunction with other staining methods performed on fixed embryo samples. PMID:25078510

  1. Effect of dietary manipulation and vaccination of turkey breeder hens on immunoglobulin levels of yolk, yolk sac and neonate poults.

    PubMed

    Bhattacharyya, A; Majumdar, S; Bhanja, S K; Mandal, A B; Dash, B B

    2018-04-01

    Two hundred turkey breeder hens and 24 viable toms of 30-35 weeks age of small white variety were distributed into two treatment groups having four replicates of 25 hens and three toms in each treatment. First four replicates were offered a turkey breeder diet (Diet A) (Nutrient requirements of poultry, 1994, National Academic Press, Washington, DC) and the rest four replicates were maintained on a higher plane of nutrition (Diet B) for 8-week duration. After 6 weeks of experimental feeding, two replicates from each treatment groups were vaccinated with ND (R 2 B) vaccine. Yolk sac of embryo from birds fed Diet B had a significantly higher (p < .05) IgG, IgM level and HI titre (log 2) than those fed Diet A. HI titre values of embryonic yolk sac from the vaccinated birds fed Diet B were significantly higher (p < .05) than that of the control groups. In addition, HI titre values were significantly higher (p < .05) in the day-old poults of the birds fed Diet B than that of those fed Diet A. There was significantly (p < .01) positive correlation between serum IgG and IgM of the breeder birds and day-old chicks. Similarly, there was significantly (p < .05) positive correlation between yolk IgG and IgM after 1-month experimental feeding and yolk sac IgG and IgM. Positive correlation (p < .05) also existed between yolk sac IgM and day-old chick serum IgM. Furthermore, the HI titres of breeder birds' serum at 14 days post-vaccination were positively correlated with their egg yolk after 10 and 15 days post-vaccination, yolk sac and day-old chicks. Thus, the study envisaged that a higher immunity in neonate poults from turkey breeders maintained on a higher plane of nutrition may be elicited as there was maternal transfer of antibodies from the serum of breeder birds to their offsprings through their yolk sac. © 2018 Blackwell Verlag GmbH.

  2. Developmental Toxicity of Dextromethorphan in Zebrafish Embryos/Larvae

    PubMed Central

    Xu, Zheng; Williams, Frederick E.; Liu, Ming-Cheh

    2012-01-01

    Dextromethorphan is widely used in over-the-counter cough and cold medications. Its efficacy and safety for infants and young children remains to be clarified. The present study was designed to use the zebrafish as a model to investigate the potential toxicity of dextromethorphan during the embryonic and larval development. Three sets of zebrafish embryos/larvae were exposed to dextromethorphan at 24 hours post fertilization (hpf), 48 hpf, and 72 hpf, respectively, during the embryonic/larval development. Compared with the 48 and 72 hpf exposure sets, the embryos/larvae in the 24 hpf exposure set showed much higher mortality rates which increased in a dose-dependent manner. Bradycardia and reduced blood flow were observed for the embryos/larvae treated with increasing concentrations of dextromethorphan. Morphological effects of dextromethorphan exposure, including yolk sac and cardiac edema, craniofacial malformation, lordosis, non-inflated swim bladder, and missing gill, were also more frequent and severe among zebrafish embryos/larvae exposed to dextromethorphan at 24 hpf. Whether the more frequent and severe developmental toxicity of dextromethorphan observed among the embryos/larvae in the 24 hpf exposure set, as compared with the 48 and 72 hpf exposure sets, is due to the developmental expression of the Phase I and Phase II enzymes involved in the metabolism of dextromethorphan remains to be clarified. A reverse transcription-polymerase chain reaction (RT-PCR) analysis, nevertheless, revealed developmental stage-dependent expression of mRNAs encoding SULT3 ST1 and SULT3 ST3, two enzymes previously shown to be capable of sulfating dextrorphan, an active metabolite of dextromethorphan. PMID:20737414

  3. Developmental toxicity of dextromethorphan in zebrafish embryos/larvae.

    PubMed

    Xu, Zheng; Williams, Frederick E; Liu, Ming-Cheh

    2011-03-01

    Dextromethorphan is widely used in over-the-counter cough and cold medications. Its efficacy and safety for infants and young children remains to be clarified. The present study was designed to use zebrafish as a model to investigate the potential toxicity of dextromethorphan during embryonic and larval development. Three sets of zebrafish embryos/larvae were exposed to dextromethorphan at 24, 48 and 72 h post fertilization (hpf), respectively, during the embryonic/larval development. Compared with the 48 and 72 hpf exposure sets, the embryos/larvae in the 24 hpf exposure set showed much higher mortality rates which increased in a dose-dependent manner. Bradycardia and reduced blood flow were observed for the embryos/larvae treated with increasing concentrations of dextromethorphan. Morphological effects of dextromethorphan exposure, including yolk sac and cardiac edema, craniofacial malformation, lordosis, non-inflated swim bladder and missing gill, were also more frequent and severe among zebrafish embryos/larvae exposed to dextromethorphan at 24 hpf. Whether the more frequent and severe developmental toxicity of dextromethorphan observed among the embryos/larvae in the 24 hpf exposure set, as compared with the 48 and 72 hpf exposure sets, is due to the developmental expression of the phase I and phase II enzymes involved in the metabolism of dextromethorphan remains to be clarified. A reverse transcription-polymerase chain reaction analysis, nevertheless, revealed developmental stage-dependent expression of mRNAs encoding SULT3 ST1 and SULT3 ST3, two enzymes previously shown to be capable of sulfating dextrorphan, an active metabolite of dextromethorphan. Copyright © 2010 John Wiley & Sons, Ltd.

  4. Contextual Fear Conditioning in Zebrafish

    ERIC Educational Resources Information Center

    Kenney, Justin W.; Scott, Ian C.; Josselyn, Sheena A.; Frankland, Paul W.

    2017-01-01

    Zebrafish are a genetically tractable vertebrate that hold considerable promise for elucidating the molecular basis of behavior. Although numerous recent advances have been made in the ability to precisely manipulate the zebrafish genome, much less is known about many aspects of learning and memory in adult fish. Here, we describe the development…

  5. Identification of double-yolked duck egg using computer vision

    PubMed Central

    Ma, Long; Sun, Ke; Tu, Kang; Pan, Leiqing; Zhang, Wei

    2017-01-01

    The double-yolked (DY) egg is quite popular in some Asian countries because it is considered as a sign of good luck, however, the double yolk is one of the reasons why these eggs fail to hatch. The usage of automatic methods for identifying DY eggs can increase the efficiency in the poultry industry by decreasing egg loss during incubation or improving sale proceeds. In this study, two methods for DY duck egg identification were developed by using computer vision technology. Transmittance images of DY and single-yolked (SY) duck eggs were acquired by a CCD camera to identify them according to their shape features. The Fisher’s linear discriminant (FLD) model equipped with a set of normalized Fourier descriptors (NFDs) extracted from the acquired images and the convolutional neural network (CNN) model using primary preprocessed images were built to recognize duck egg yolk types. The classification accuracies of the FLD model for SY and DY eggs were 100% and 93.2% respectively, while the classification accuracies of the CNN model for SY and DY eggs were 98% and 98.8% respectively. The CNN-based algorithm took about 0.12 s to recognize one sample image, which was slightly faster than the FLD-based (about 0.20 s). Finally, this work compared two classification methods and provided the better method for DY egg identification. PMID:29267387

  6. Identification of double-yolked duck egg using computer vision.

    PubMed

    Ma, Long; Sun, Ke; Tu, Kang; Pan, Leiqing; Zhang, Wei

    2017-01-01

    The double-yolked (DY) egg is quite popular in some Asian countries because it is considered as a sign of good luck, however, the double yolk is one of the reasons why these eggs fail to hatch. The usage of automatic methods for identifying DY eggs can increase the efficiency in the poultry industry by decreasing egg loss during incubation or improving sale proceeds. In this study, two methods for DY duck egg identification were developed by using computer vision technology. Transmittance images of DY and single-yolked (SY) duck eggs were acquired by a CCD camera to identify them according to their shape features. The Fisher's linear discriminant (FLD) model equipped with a set of normalized Fourier descriptors (NFDs) extracted from the acquired images and the convolutional neural network (CNN) model using primary preprocessed images were built to recognize duck egg yolk types. The classification accuracies of the FLD model for SY and DY eggs were 100% and 93.2% respectively, while the classification accuracies of the CNN model for SY and DY eggs were 98% and 98.8% respectively. The CNN-based algorithm took about 0.12 s to recognize one sample image, which was slightly faster than the FLD-based (about 0.20 s). Finally, this work compared two classification methods and provided the better method for DY egg identification.

  7. 21 CFR 160.185 - Dried egg yolks.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... preservative. (2) Yeast procedure. The pH of the liquid egg yolks is adjusted to the range of 6.0 to 7.0, if... maintained by adding food-grade baker's yeast (Saccharomyces cerevisiae). The quantity of yeast used and the...

  8. 21 CFR 160.185 - Dried egg yolks.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... preservative. (2) Yeast procedure. The pH of the liquid egg yolks is adjusted to the range of 6.0 to 7.0, if... maintained by adding food-grade baker's yeast (Saccharomyces cerevisiae). The quantity of yeast used and the...

  9. 21 CFR 160.185 - Dried egg yolks.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... preservative. (2) Yeast procedure. The pH of the liquid egg yolks is adjusted to the range of 6.0 to 7.0, if... maintained by adding food-grade baker's yeast (Saccharomyces cerevisiae). The quantity of yeast used and the...

  10. 21 CFR 160.185 - Dried egg yolks.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... preservative. (2) Yeast procedure. The pH of the liquid egg yolks is adjusted to the range of 6.0 to 7.0, if... maintained by adding food-grade baker's yeast (Saccharomyces cerevisiae). The quantity of yeast used and the...

  11. Yolk testosterone reduces oxidative damages during postnatal development

    PubMed Central

    Noguera, José Carlos; Alonso-Alvarez, Carlos; Kim, Sin-Yeon; Morales, Judith; Velando, Alberto

    2011-01-01

    Conditions experienced during early life can influence the development of an organism and several physiological traits, even in adulthood. An important factor is the level of oxidative stress experienced during early life. In birds, extra-genomic egg substances, such as the testosterone hormone, may exert a widespread influence over the offspring phenotype. Interestingly, testosterone can also upregulate the bioavailability of certain antioxidants but simultaneously increases the susceptibility to oxidative stress in adulthood. However, little is known about the effects of maternally derived yolk testosterone on oxidative stress in developing birds. Here, we investigated the role of yolk testosterone on oxidative stress of yellow-legged gull chicks during their early development by experimentally increasing yolk testosterone levels. Levels of antioxidants, reactive oxygen species and lipid oxidative damage were determined in plasma during nestlings' growth. Our results revealed that, contrary to control chicks, birds hatched from testosterone-treated eggs did not show an increase in the levels of oxidative damage during postnatal development. Moreover, the same birds showed a transient increase in plasma antioxidant levels. Our results suggest that yolk testosterone may shape the oxidative stress-resistance phenotype of the chicks during early development owing to an increase in antioxidant defences and repair processes. PMID:20659922

  12. Cryoprotective and contraceptive properties of egg yolk as an additive in rooster sperm diluents.

    PubMed

    Santiago-Moreno, Julián; Castaño, Cristina; Toledano-Díaz, Adolfo; Coloma, Miguel A; López-Sebastián, Antonio; Prieto, María T; Campo, Jose L

    2012-12-01

    The addition of chicken egg yolk to semen extenders is thought to reduce the fertilizing potential of rooster spermatozoa--but not (or at least not as much) that of other avian species. The aim of the present study was to determine whether quail egg yolk, a novel extender additive, provides advantages over chicken egg yolk in the cryopreservation of rooster spermatozoa. Experiments were also performed to determine whether the harmful effect of egg yolk occurs during cryopreservation or during fertilization after artificial insemination. Heterospermic rooster semen samples were divided into aliquots and cooled in a polyvinylpyrrolidone-based medium containing 15% chicken egg yolk, 15% quail egg yolk or no egg yolk at all. The viability of spermatozoa of cooled samples (5 °C) without egg yolk were less viable (P<0.01) than those of samples containing either type of egg yolk. The same aliquots were then cryopreserved for 15 days. Thawed spermatozoa preserved without egg yolk showed lower motility (P<0.001) and viability (P<0.001) than those in samples diluted with either type of egg yolk extender. No eggs were fertilized when hens were inseminated with semen that had been diluted with chicken egg yolk. The fertilization rate was only slightly higher when sperm diluted with quail egg yolk was used (1.5%). The best results were obtained when no egg yolk was used (13.8%). These results show that the addition of egg yolk of either type protects rooster sperm cells against cold shock and during freezing and thawing, but exerts a contraceptive effect in the genital tract of the hen. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Developmental toxicity of CdTe QDs in zebrafish embryos and larvae

    NASA Astrophysics Data System (ADS)

    Duan, Junchao; Yu, Yongbo; Li, Yang; Yu, Yang; Li, Yanbo; Huang, Peili; Zhou, Xianqing; Peng, Shuangqing; Sun, Zhiwei

    2013-07-01

    Quantum dots (QDs) have widely been used in biomedical and biotechnological applications. However, few studies focus on the assessing toxicity of QDs exposure in vivo. In this study, zebrafish embryos were treated with CdTe QDs (4 nm) during 4-96 h post-fertilization (hpf). Mortality, hatching rate, malformation, heart rate, and QDs uptake were detected. We also measured the larval behavior to analyze whether QDs had persistent effects on larvae locomotor activity at 144 hpf. The results showed that as the exposure dosages increased, the hatching rate and heart rate of zebrafish embryos were decreased, while the mortality increased. Exposure to QDs caused embryonic malformations, including head malformation, pericardial edema, yolk sac edema, bent spine, and yolk not depleted. QDs fluorescence was mainly localized in the intestines region. The larval behavior testing showed that the total swimming distance was decreased in a dose-dependent manner. The lowest dose (2.5 nM QDs) produced substantial hyperactivity while the higher doses groups (5, 10, and 20 nM QDs) elicited remarkably hypoactivity in dark periods. In summary, the data of this article indicated that QDs caused embryonic developmental toxicity, resulted in persistent effects on larval behavior.

  14. Montmorillonite clay alters toxicity of silver nanoparticles in zebrafish (Danio rerio) eleutheroembryo.

    PubMed

    Gupta, Govind Sharan; Dhawan, Alok; Shanker, Rishi

    2016-11-01

    An exponential development in the use of silver nanoparticles (AgNPs) in consumer products has accelerated their release in aquatic environment. As the AgNPs enters into the aquatic systems, their fate may change due to interactions with abiotic (e.g. clay particles) or biotic factors. The abundantly present clay particles are expected to more prone for interaction with nanoparticles in aquatic systems. In the present study, it is demonstrated that AgNPs interacts with clay particles and forms heteroagglomerates. Furthermore, an impact on toxicity potential of AgNPs after interactions with clay particles was assessed by using zebrafish eleutheroembryos (72 h post hatching) as an in vivo model. The mortality rate of zebrafish eleutheroembryos was higher in case of exposure to AgNPs-clay complexes (pH 4.0 and 7.0) as compared to bare AgNPs. In addition, at earlier time points, the eleutheroembryos expressed higher levels of morphological changes in tail, yolk and pericardia, but the edema in yolk sac was followed by cell death. It can be concluded from the observations made in the present study that the inorganic colloids in the aquatic matrices can alter the fate and toxicity potential of nanoparticles. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Positional cloning of zebrafish ferroportin1 identifies a conserved vertebrate iron exporter.

    PubMed

    Donovan, A; Brownlie, A; Zhou, Y; Shepard, J; Pratt, S J; Moynihan, J; Paw, B H; Drejer, A; Barut, B; Zapata, A; Law, T C; Brugnara, C; Lux, S E; Pinkus, G S; Pinkus, J L; Kingsley, P D; Palis, J; Fleming, M D; Andrews, N C; Zon, L I

    2000-02-17

    Defects in iron absorption and utilization lead to iron deficiency and overload disorders. Adult mammals absorb iron through the duodenum, whereas embryos obtain iron through placental transport. Iron uptake from the intestinal lumen through the apical surface of polarized duodenal enterocytes is mediated by the divalent metal transporter, DMTi. A second transporter has been postulated to export iron across the basolateral surface to the circulation. Here we have used positional cloning to identify the gene responsible for the hypochromic anaemia of the zebrafish mutant weissherbst. The gene, ferroportin1, encodes a multiple-transmembrane domain protein, expressed in the yolk sac, that is a candidate for the elusive iron exporter. Zebrafish ferroportin1 is required for the transport of iron from maternally derived yolk stores to the circulation and functions as an iron exporter when expressed in Xenopus oocytes. Human Ferroportin1 is found at the basal surface of placental syncytiotrophoblasts, suggesting that it also transports iron from mother to embryo. Mammalian Ferroportin1 is expressed at the basolateral surface of duodenal enterocytes and could export cellular iron into the circulation. We propose that Ferroportin1 function may be perturbed in mammalian disorders of iron deficiency or overload.

  16. Cryopreservation of collared peccaries (Tayassu tajacu) semen using a powdered coconut water (ACP-116c) based extender plus various concentrations of egg yolk and glycerol.

    PubMed

    Silva, M A; Peixoto, G C X; Lima, G L; Bezerra, J A B; Campos, L B; Paiva, A L C; Paula, V V; Silva, A R

    2012-08-01

    The objective was to determine the effectiveness of a powdered coconut water-based extender (ACP-116c), plus various concentrations of egg-yolk and glycerol, as an alternative for cryopreservation of collared peccary semen. Twelve ejaculates were obtained from captive adult males by electroejaculation, and evaluated for sperm motility, kinetic rating, viability, morphology, and functional membrane integrity. The ejaculates were apportioned into aliquots that were diluted in Tris plus 10% egg yolk and 3% glycerol, or in ACP-116c plus 10 or 20% egg yolk and 1.5 or 3% glycerol. Samples were frozen in liquid nitrogen and, after 1 mo, thawed at 37 °C for 1 min. After thawing, samples were evaluated as reported for fresh semen, and also for sperm membrane integrity (fluorescent probes) and kinematic parameters (computerized analysis). Results were presented as means ± SEM. Freezing and thawing decreased sperm characteristics relative to fresh semen. Overall, ACP-116c plus 20% egg yolk and 3% glycerol provided better (P < 0.05) sperm motility and kinetic rating (48 ± 6.1% and 2.8 ± 0.2, respectively) after thawing than Tris extender (30.4 ± 5.7% and 2.4 ± 0.2). However, there were no differences (P > 0.05) among treatments with regard to the other sperm characteristics. Based on computerized motion analysis, total (26.5 ± 5.9%) and progressive (8.1 ± 2.2%) motility were best preserved (P < 0.05) with the above-mentioned treatment. In conclusion, a coconut water-based extender, ACP-116c, plus 20% egg yolk and 3% glycerol, was effective for cryopreservation of semen from collared peccaries. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Yolk sac development in lizards (Lacertilia: Scincidae): New perspectives on the egg of amniotes.

    PubMed

    Stewart, James R; Thompson, Michael B

    2017-04-01

    Embryos of oviparous reptiles develop on the surface of a large mass of yolk, which they metabolize to become relatively large hatchlings. Access to the yolk is provided by tissues growing outward from the embryo to cover the surface of the yolk. A key feature of yolk sac development is a dedicated blood vascular system to communicate with the embryo. The best known model for yolk sac development and function of oviparous amniotes is based on numerous studies of birds, primarily domestic chickens. In this model, the vascular yolk sac forms the perimeter of the large yolk mass and is lined by a specialized epithelium, which takes up, processes and transports yolk nutrients to the yolk sac blood vessels. Studies of lizard yolk sac development, dating to more than 100 years ago, report characteristics inconsistent with this model. We compared development of the yolk sac from oviposition to near hatching in embryonic series of three species of oviparous scincid lizards to consider congruence with the pattern described for birds. Our findings reinforce results of prior studies indicating that squamate reptiles mobilize and metabolize the large yolk reserves in their eggs through a process unknown in other amniotes. Development of the yolk sac of lizards differs from birds in four primary characteristics, migration of mesoderm, proliferation of endoderm, vascular development and cellular diversity within the yolk sac cavity. Notably, all of the yolk is incorporated into cells relatively early in development and endodermal cells within the yolk sac cavity align along blood vessels which course throughout the yolk sac cavity. The pattern of uptake of yolk by endodermal cells indicates that the mechanism of yolk metabolism differs between lizards and birds and that the evolution of a fundamental characteristic of embryonic nutrition diverged in these two lineages. Attributes of the yolk sac of squamates reveal the existence of phylogenetic diversity among amniote lineages

  18. Comparison of Antemortem and Environmental Samples for Zebrafish Health Monitoring and Quarantine.

    PubMed

    Crim, Marcus J; Lawrence, Christian; Livingston, Robert S; Rakitin, Andrei; Hurley, Shane J; Riley, Lela K

    2017-07-01

    Molecular diagnostic assays offer both exquisite sensitivity and the ability to test a wide variety of sample types. Various types of environmental sample, such as detritus and concentrated water, might provide a useful adjunct to sentinels in routine zebrafish health monitoring. Similarly, antemortem sampling would be advantageous for expediting zebrafish quarantine, without euthanasia of valuable fish. We evaluated the detection of Mycobacterium chelonae, M. fortuitum, M. peregrinum, Pseudocapillaria tomentosa, and Pseudoloma neurophilia in zebrafish, detritus, pooled feces, and filter membranes after filtration of 1000-, 500-, and 150-mL water samples by real-time PCR analysis. Sensitivity varied according to sample type and pathogen, and environmental sampling was significantly more sensitive than zebrafish sampling for detecting Mycobacterium spp. but not for Pseudocapillaria neurophilia or Pseudoloma tomentosa. The results of these experiments provide strong evidence of the utility of multiple sample types for detecting pathogens according to each pathogen's life cycle and ecological niche within zebrafish systems. In a separate experiment, zebrafish subclinically infected with M. chelonae, M. marinum, Pleistophora hyphessobryconis, Pseudocapillaria tomentosa, or Pseudoloma neurophilia were pair-spawned and individually tested with subsets of embryos from each clutch that received no rinse, a fluidizing rinse, or were surface-disinfected with sodium hypochlorite. Frequently, one or both parents were subclinically infected with pathogen(s) that were not detected in any embryo subset. Therefore, negative results from embryo samples may not reflect the health status of the parent zebrafish.

  19. Comparison of Antemortem and Environmental Samples for Zebrafish Health Monitoring and Quarantine

    PubMed Central

    Crim, Marcus J; Lawrence, Christian; Livingston, Robert S; Rakitin, Andrei; Hurley, Shane J; Riley, Lela K

    2017-01-01

    Molecular diagnostic assays offer both exquisite sensitivity and the ability to test a wide variety of sample types. Various types of environmental sample, such as detritus and concentrated water, might provide a useful adjunct to sentinels in routine zebrafish health monitoring. Similarly, antemortem sampling would be advantageous for expediting zebrafish quarantine, without euthanasia of valuable fish. We evaluated the detection of Mycobacterium chelonae, M. fortuitum, M. peregrinum, Pseudocapillaria tomentosa, and Pseudoloma neurophilia in zebrafish, detritus, pooled feces, and filter membranes after filtration of 1000-, 500-, and 150-mL water samples by real-time PCR analysis. Sensitivity varied according to sample type and pathogen, and environmental sampling was significantly more sensitive than zebrafish sampling for detecting Mycobacterium spp. but not for Pseudocapillaria neurophilia or Pseudoloma tomentosa. The results of these experiments provide strong evidence of the utility of multiple sample types for detecting pathogens according to each pathogen's life cycle and ecological niche within zebrafish systems. In a separate experiment, zebrafish subclinically infected with M. chelonae, M. marinum, Pleistophora hyphessobryconis, Pseudocapillaria tomentosa, or Pseudoloma neurophilia were pair-spawned and individually tested with subsets of embryos from each clutch that received no rinse, a fluidizing rinse, or were surface-disinfected with sodium hypochlorite. Frequently, one or both parents were subclinically infected with pathogen(s) that were not detected in any embryo subset. Therefore, negative results from embryo samples may not reflect the health status of the parent zebrafish. PMID:28724491

  20. The Presence or Absence of Intestinal Microbiota Affects Lipid Deposition and Related Genes Expression in Zebrafish (Danio rerio).

    PubMed

    Sheng, Yi; Ren, Hui; Limbu, Samwel M; Sun, Yuhong; Qiao, Fang; Zhai, Wanying; Du, Zhen-Yu; Zhang, Meiling

    2018-01-01

    Understanding how intestinal microbiota alters energy homeostasis and lipid metabolism is a critical process in energy balance and health. However, the exact role of intestinal microbiota in the regulation of lipid metabolism in fish remains unclear. Here, we used two zebrafish models (germ-free and antibiotics-treated zebrafish) to identify the role of intestinal microbiota in lipid metabolism. Conventional and germ-free zebrafish larvae were fed with egg yolk. Transmission electron microscopy was used to detect the presence of lipid droplets in the intestinal epithelium. The results showed that, microbiota increased lipid accumulation in the intestinal epithelium. The mRNA sequencing technology was used to assess genes expression level. We found majority of the differentially expressed genes were related to lipid metabolism. Due to the limitation of germ-free zebrafish larvae, antibiotics-treated zebrafish were also used to identify the relationship between the gut microbiota and the host lipid metabolism. Oil-red staining showed antibiotics-treated zebrafish had less intestinal lipid accumulation than control group. The mRNA expression of genes related to lipid metabolism in liver and intestine was also quantified by using real-time PCR. The results indicated that apoa4 , hsl , cox15 , slc2a1a , and lss were more related to intestinal bacteria in fish, while the influence of intestinal microbiota on the activity of fabp6 , acsl5 , cd36 , and gpat2 was different between the liver and intestine. This study identified several genes regulated by intestinal microbiota. Furthermore, the advantages and disadvantages of each model have been discussed. This study provides valuable information for exploring host-microbiota interactions in zebrafish in future.

  1. MicroXRF tomographic visualization of zinc and iron in the zebrafish embryo at the onset of the hatching period

    SciT

    Bourassa, Daisy; Gleber, Sophie-Charlotte; Vogt, Stefan

    2016-01-01

    Transition metals such as zinc, copper, and iron play key roles in cellular proliferation, cell differentiation, growth, and development. Over the past decade, advances in synchrotron X-ray fluorescence instrumentation presented new opportunities for the three-dimensional mapping of trace metal distributions within intact specimens. Taking advantage of microXRF tomography, we visualized the 3D distribution of zinc and iron in a zebrafish embryo at the onset of the hatching period. The reconstructed volumetric data revealed distinct differences in the elemental distributions, with zinc predominantly localized to the yolk and yolk extension, and iron to various regions of the brain as well asmore » the myotome extending along the dorsal side of the embryo. The data set complements an earlier tomographic study of an embryo at the pharyngula stage (24 hpf), thus offering new insights into the trace metal distribution at key stages of embryonic development.« less

  2. Automatic zebrafish heartbeat detection and analysis for zebrafish embryos.

    PubMed

    Pylatiuk, Christian; Sanchez, Daniela; Mikut, Ralf; Alshut, Rüdiger; Reischl, Markus; Hirth, Sofia; Rottbauer, Wolfgang; Just, Steffen

    2014-08-01

    A fully automatic detection and analysis method of heartbeats in videos of nonfixed and nonanesthetized zebrafish embryos is presented. This method reduces the manual workload and time needed for preparation and imaging of the zebrafish embryos, as well as for evaluating heartbeat parameters such as frequency, beat-to-beat intervals, and arrhythmicity. The method is validated by a comparison of the results from automatic and manual detection of the heart rates of wild-type zebrafish embryos 36-120 h postfertilization and of embryonic hearts with bradycardia and pauses in the cardiac contraction.

  3. Small heat shock proteins are necessary for heart migration and laterality determination in zebrafish

    PubMed Central

    Lahvic, Jamie L.; Ji, Yongchang; Marin, Paloma; Zuflacht, Jonah P.; Springel, Mark W.; Wosen, Jonathan E.; Davis, Leigh; Hutson, Lara D.; Amack, Jeffrey D.; Marvin, Martha J.

    2013-01-01

    Small heat shock proteins (sHsps) regulate cellular functions not only under stress, but also during normal development, when they are expressed in organ-specific patterns. Here we demonstrate that two small heat shock proteins expressed in embryonic zebrafish heart, hspb7 and hspb12, have roles in the development of left-right asymmetry. In zebrafish, laterality is determined by the motility of cilia in Kupffer’s vesicle (KV), where hspb7 is expressed; knockdown of hspb7 causes laterality defects by disrupting the motility of these cilia. In embryos with reduced hspb7, the axonemes of KV cilia have a 9+0 structure, while control embyros have a predominately 9+2 structure. Reduction of either hspb7 or hspb12 alters the expression pattern of genes that propagate the signals that establish left-right asymmetry: the nodal-related gene southpaw (spaw) in the lateral plate mesoderm, and its downstream targets pitx2, lefty1 and lefty2. Partial depletion of hspb7 causes concordant heart, brain and visceral laterality defects, indicating that loss of KV cilia motility leads causes coordinated but randomized laterality. Reducing hspb12 leads to similar alterations in the expression of downstream laterality genes, but at a lower penetrance. Simultaneous reduction of hspb7 and hspb12 randomizes heart, brain and visceral laterality, suggesting that these two genes have partially redundant functions in the establishment of left-right asymmetry. In addition, both hspb7 and hspb12 are expressed in the precardiac mesoderm and in the yolk syncytial layer, which supports the migration and fusion of mesodermal cardiac precursors. In embryos in which the reduction of hspb7 or hspb12 was limited to the yolk, migration defects predominated, suggesting that the yolk expression of these genes rather than heart expression is responsible for the migration defects. PMID:24140541

  4. Quaternary and tertiary aldoxime antidotes for organophosphate exposure in a zebrafish model system

    SciT

    Schmidt, Hayden R.; Radić, Zoran; Taylor, Palmer

    The zebrafish is rapidly becoming an important model system for screening of new therapeutics. Here we evaluated the zebrafish as a potential pharmacological model for screening novel oxime antidotes to organophosphate (OP)-inhibited acetylcholinesterase (AChE). The k{sub i} values determined for chlorpyrifos oxon (CPO) and dichlorvos (DDVP) showed that CPO was a more potent inhibitor of both human and zebrafish AChE, but overall zebrafish AChE was less sensitive to OP inhibition. In contrast, aldoxime antidotes, the quaternary ammonium 2-PAM and tertiary amine RS-194B, showed generally similar overall reactivation kinetics, k{sub r}, in both zebrafish and human AChE. However, differences between themore » K{sub ox} and k{sub 2} constants suggest that zebrafish AChE associates more tightly with oximes, but has a slower maximal reactivation rate than human AChE. Homology modeling suggests that these kinetic differences result from divergences in the amino acids lining the entrance to the active site gorge. Although 2-PAM had the more favorable in vitro reactivation kinetics, RS-194B was more effective antidote in vivo. In intact zebrafish embryos, antidotal treatment with RS-194B rescued embryos from OP toxicity, whereas 2-PAM had no effect. Dechorionation of the embryos prior to antidotal treatment allowed both 2-PAM and RS-194B to rescue zebrafish embryos from OP toxicity. Interestingly, RS-194B and 2-PAM alone increased cholinergic motor activity in dechorionated embryos possibly due to the reversible inhibition kinetics, K{sub i} and αK{sub i}, of the oximes. Together these results demonstrate that the zebrafish at various developmental stages provides an excellent model for investigating membrane penetrant antidotes to OP exposure. - Highlights: • Zebrafish AChE shares significant structural similarities with human AChE. • OP-inhibited zebrafish and human AChE exhibit similar reactivation kinetics. • The zebrafish chorion is permeable to BBB penetrant

  5. Zebrafish pancreas development.

    PubMed

    Tiso, Natascia; Moro, Enrico; Argenton, Francesco

    2009-11-27

    An accurate understanding of the molecular events governing pancreas development can have an impact on clinical medicine related to diabetes, obesity and pancreatic cancer, diseases with a high impact in public health. Until 1996, the main animal models in which pancreas formation and differentiation could be studied were mouse and, for some instances related to early development, chicken and Xenopus. Zebrafish has penetrated this field very rapidly offering a new model of investigation; by joining functional genomics, genetics and in vivo whole mount visualization, Danio rerio has allowed large scale and fine multidimensional analysis of gene functions during pancreas formation and differentiation.

  6. Embryonic senescence and laminopathies in a progeroid zebrafish model.

    PubMed

    Koshimizu, Eriko; Imamura, Shintaro; Qi, Jie; Toure, Jamal; Valdez, Delgado M; Carr, Christopher E; Hanai, Jun-ichi; Kishi, Shuji

    2011-03-30

    Mutations that disrupt the conversion of prelamin A to mature lamin A cause the rare genetic disorder Hutchinson-Gilford progeria syndrome and a group of laminopathies. Our understanding of how A-type lamins function in vivo during early vertebrate development through aging remains limited, and would benefit from a suitable experimental model. The zebrafish has proven to be a tractable model organism for studying both development and aging at the molecular genetic level. Zebrafish show an array of senescence symptoms resembling those in humans, which can be targeted to specific aging pathways conserved in vertebrates. However, no zebrafish models bearing human premature senescence currently exist. We describe the induction of embryonic senescence and laminopathies in zebrafish harboring disturbed expressions of the lamin A gene (LMNA). Impairments in these fish arise in the skin, muscle and adipose tissue, and sometimes in the cartilage. Reduced function of lamin A/C by translational blocking of the LMNA gene induced apoptosis, cell-cycle arrest, and craniofacial abnormalities/cartilage defects. By contrast, induced cryptic splicing of LMNA, which generates the deletion of 8 amino acid residues lamin A (zlamin A-Δ8), showed embryonic senescence and S-phase accumulation/arrest. Interestingly, the abnormal muscle and lipodystrophic phenotypes were common in both cases. Hence, both decrease-of-function of lamin A/C and gain-of-function of aberrant lamin A protein induced laminopathies that are associated with mesenchymal cell lineages during zebrafish early development. Visualization of individual cells expressing zebrafish progerin (zProgerin/zlamin A-Δ37) fused to green fluorescent protein further revealed misshapen nuclear membrane. A farnesyltransferase inhibitor reduced these nuclear abnormalities and significantly prevented embryonic senescence and muscle fiber damage induced by zProgerin. Importantly, the adult Progerin fish survived and remained fertile with

  7. Type-IV antifreeze proteins are essential for epiboly and convergence in gastrulation of zebrafish embryos.

    PubMed

    Xiao, Qing; Xia, Jian-Hong; Zhang, Xiao-Juan; Li, Zhi; Wang, Yang; Zhou, Li; Gui, Jian-Fang

    2014-01-01

    Many organisms in extremely cold environments such as the Antarctic Pole have evolved antifreeze molecules to prevent ice formation. There are four types of antifreeze proteins (AFPs). Type-IV antifreeze proteins (AFP4s) are present also in certain temperate and even tropical fish, which has raised a question as to whether these AFP4s have important functions in addition to antifreeze activity. Here we report the identification and functional analyses of AFP4s in cyprinid fish. Two genes, namely afp4a and afp4b coding for AFP4s, were identified in gibel carp (Carassius auratus gibelio) and zebrafish (Danio rerio). In both species, afp4a and afp4b display a head-to-tail tandem arrangement and share a common 4-exonic gene structure. In zebrafish, both afp4a and afp4b were found to express specifically in the yolk syncytial layer (YSL). Interestingly, afp4a expression continues in YSL and digestive system from early embryos to adults, whereas afp4b expression is restricted to embryogenesis. Importantly, we have shown by using afp4a-specific and afp4b-specifc morpholino knockdown and cell lineage tracing approaches that AFP4a participates in epiboly progression by stabilizing yolk cytoplasmic layer microtubules, and AFP4b is primarily related to convergence movement. Therefore, both AFP4 proteins are essential for gastrulation of zebrafish embryos. Our current results provide first evidence that AFP such as AFP4 has important roles in regulating developmental processes besides its well-known function as antifreeze factors.

  8. Zebrafish Pronephros Development.

    PubMed

    Naylor, Richard W; Qubisi, Sarah S; Davidson, Alan J

    The pronephros is the first kidney type to form in vertebrate embryos. The first step of pronephrogenesis in the zebrafish is the formation of the intermediate mesoderm during gastrulation, which occurs in response to secreted morphogens such as BMPs and Nodals. Patterning of the intermediate mesoderm into proximal and distal cell fates is induced by retinoic acid signaling with downstream transcription factors including wt1a, pax2a, pax8, hnf1b, sim1a, mecom, and irx3b. In the anterior intermediate mesoderm, progenitors of the glomerular blood filter migrate and fuse at the midline and recruit a blood supply. More posteriorly localized tubule progenitors undergo epithelialization and fuse with the cloaca. The Notch signaling pathway regulates the formation of multi-ciliated cells in the tubules and these cells help propel the filtrate to the cloaca. The lumenal sheer stress caused by flow down the tubule activates anterior collective migration of the proximal tubules and induces stretching and proliferation of the more distal segments. Ultimately these processes create a simple two-nephron kidney that is capable of reabsorbing and secreting solutes and expelling excess water-processes that are critical to the homeostasis of the body fluids. The zebrafish pronephric kidney provides a simple, yet powerful, model system to better understand the conserved molecular and cellular progresses that drive nephron formation, structure, and function.

  9. Zebrafish as tools for drug discovery.

    PubMed

    MacRae, Calum A; Peterson, Randall T

    2015-10-01

    The zebrafish has become a prominent vertebrate model for disease and has already contributed to several examples of successful phenotype-based drug discovery. For the zebrafish to become useful in drug development more broadly, key hurdles must be overcome, including a more comprehensive elucidation of the similarities and differences between human and zebrafish biology. Recent studies have begun to establish the capabilities and limitations of zebrafish for disease modelling, drug screening, target identification, pharmacology, and toxicology. As our understanding increases and as the technologies for manipulating zebrafish improve, it is hoped that the zebrafish will have a key role in accelerating the emergence of precision medicine.

  10. Sperm characteristics following freezing in extenders supplemented with whole egg yolk and different concentrations of low-density lipoproteins in the collared peccary (Pecari tajacu).

    PubMed

    Souza, Ana Liza Paz; Lima, Gabriela Liberalino; Peixoto, Gislayne Christianne Xavier; de Souza Castelo, Thibério; Oliveira, Maria Glaucia Carlos; de Paula, Valéria Veras; Silva, Alexandre Rodrigues

    2015-12-01

    The aim of the current study was to compare sperm quality characteristics of the collared peccary (Pecari tajacu) following freezing in extenders supplemented with whole egg yolk and different concentrations of low-density lipoproteins (LDL). Semen from 11 adult males was obtained by electroejaculation and evaluated for sperm motility, vigor, morphology as well as membrane integrity analyzed by the hypo-osmotic swelling (HOS) test and a fluorescent staining. Moreover, the semen was diluted in a Tris-based extender containing 20% egg yolk (control group) or 5, 10 or 20% LDL (treatment groups). The semen samples were frozen in liquid nitrogen and thawed in a water bath for 60s at 37°C. The treatments did not affect (p>0.05) sperm vigor, morphology or membrane integrity analyzed by the HOS test. However, post-thaw sperm motility was significantly higher (p<0.05) in the extender supplemented with 20% LDL (36.4 ± 5.3%) compared with the egg yolk extender and extender supplemented with 10% LDL. Furthermore, the percentage of membrane-intact frozen-thawed spermatozoa analyzed by the fluorescent staining was significantly higher (p<0.05) in the extender supplemented with 20% LDL (27.4 ± 6.5%) than in the other groups. In conclusion, 20% LDL can be used to substitute the whole egg yolk as a cryoprotective additive for freezing semen of the collared peccary. Copyright © 2015 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  11. Fishy Odor and TMA Content Levels in Duck Egg Yolks.

    PubMed

    Li, Xingzheng; Yuan, Gongjiao; Chen, Xia; Guo, Yuying; Yang, Ning; Pi, Jinsong; Zhang, Hao; Zheng, Jiangxia

    2018-01-01

    The differences between the trimethylamine (TMA) content levels in duck and chicken egg yolks under normal dietary conditions were compared. Moreover, the association between the polymorphisms of the duck FMO3 gene and TMA content levels in duck egg yolks was analyzed. Then, to detect the mutations associated with the fish-flavor trait, duck populations were selected for a high-choline diet experiment, which was followed by full-length sequencing of the FMO3 exons. The results showed that the TMA content levels in duck eggs (3.60 μg/g) were significantly higher than those in chicken eggs (2.35 μg/g) under normal dietary conditions (P < 0.01). With regard to the high-choline diet, the average TMA content levels in duck egg yolks (9.21 μg/g; P < 0.01) increased significantly. Furthermore, 5 SNPs reported in Ensembl database were detected in duck FMO3 exons. However, no mutation loci were found to be significantly associated with the TMA content levels in duck egg yolks. Besides, duck liver FMO3 mRNA expression levels were not associated with the TMA content levels. The results indicated that excessive TMA deposition in duck eggs is one of main factors causing the fishy odor in duck eggs, and the addition of choline in the ducks' diets was responsible for inducing an increase in the TMA content levels in duck eggs. Our study can help to diminish the fishy taste in duck eggs by reducing the amount of supplemented choline. Furthermore, this study laid a solid foundation for revealing the genetic factors involved in the fishy odor in duck eggs. © 2017 Institute of Food Technologists®.

  12. Insulin-egg yolk dispersions in self microemulsifying system.

    PubMed

    Singnurkar, P S; Gidwani, S K

    2008-11-01

    Formulation of insulin into a microemulsion very often presents a physicochemical instability during their preparation and storage. In order to overcome this lack of stability and facilitate the handling of these colloidal systems, stabilization of insulin in presence of hydrophobic components of a microemulsion appears as the most promising strategy. The present paper reports the use of egg yolk for stabilization of insulin in self microemulsifying dispersions. Insulin loaded egg yolk self microemulsifying dispersions were prepared by lyophilization followed by dispersion into self microemulsifying vehicle. The physicochemical characterization of selfmicroemulsifying dispersions includes such as insulin encapsulation efficiency, in vitro stability of insulin in presence of proteolytic enzymes and in vitro release. The biological activity of insulin from the dispersion was estimated by enzyme-linked immunosorbant assay and in vivo using Wistar diabetic rats. The particle size ranged 1.023±0.316 μm in diameter and insulin encapsulation efficiency was 98.2±0.9 %. Insulin hydrophobic self microemulsifying dispersions suppressed insulin release in pH 7.4 phosphate buffer and shown to protect insulin from enzymatic degradation in vitro in presence of chymotripsin. Egg yolk encapsulated insulin was bioactive, demonstrated through both in vivo and in vitro.

  13. Replacing egg yolk with soybean lecithin in the cryopreservation of stallion semen.

    PubMed

    Papa, Frederico Ozanam; Felício, Gabriel Barcelos; Melo-Oña, Cely Marini; Alvarenga, Marco Antonio; De Vita, Bruna; Trinque, Cássio; Puoli-Filho, José Nicolau P; Dell'Aqua, José Antonio

    2011-11-01

    The objective of this study was to determine whether replacing the egg yolk with soybean lecithin in the Botu-Crio® cryodiluent would maintain the fertility of cryopreserved stallion sperm. Two experiments were performed to evaluate cell freezability. In experiment 1, sperm from 15 stallions were frozen in Botu-Crio® (BC) or Botu-Crio® which contained 45g/L soybean lecithin (BCLS45) in place of the egg yolk. In experiment 2, we compared different concentrations of soybean lecithin: 0, 10.0, 12.5, 15.0, 17.5 and 20.0g/L (BC, BCLS10, BCLS12.5, BCLS17.5 and BCLS20, respectively). In experiment 1, sperm frozen in BC and BCLS45 exhibited similar (P>0.05) percentages of total motile sperm (61% and 61%, respectively); progressively motile sperm (27% and 27%, respectively) and sperm with intact plasma membranes (IMP; 53% and 57%, respectively). Similarly, sperm frozen in BC or BC containing any concentration of soybean lecithin maintained similar (P>0.05) percentages of total motile sperm (61-68%) and progressively motile sperm (27-31%). In the first fertility trial, we used cryopreserved semen from a single stallion was inseminated into mares. The semen from the sperm that were frozen in BC diluent resulted in a higher fertility rate (66%, 16/24) compared to the sperm that were frozen in BCLS45 diluent (17%, 5/29; P<0.01). Similarly, in a second fertility trial, the mares that were inseminated with the sperm that were frozen in BC diluent exhibited a higher fertility rate (66%, 16/24) compared to the mares that were inseminated with the sperm that were frozen in BCLS20 (40%, 10/25; P<0.05). Finally, in a third trial, the sperm that were frozen in BC resulted in a higher fertility rate in mares (75%, 18/24) compared to the sperm that were frozen in BCLS10 (41%, 10/24; P<0.05). Although replacing the egg yolk in the BC cryodiluent with soybean lecithin provided similar laboratory results for stallion sperm, after cryopreservation, the sperm that was frozen with soybean

  14. Effect of different concentrations of egg yolk and virgin coconut oil in Tris-based extenders on chilled and frozen-thawed bull semen.

    PubMed

    Tarig, A A; Wahid, H; Rosnina, Y; Yimer, N; Goh, Y M; Baiee, F H; Khumran, A M; Salman, H; Ebrahimi, M

    2017-07-01

    The aim of this study was to evaluate the effects of 8% virgin coconut oil (VCO) combined with different percentages of egg yolk in Tris extender on the quality of chilled and frozen-thawed bull semen. A total of 24 ejaculates from four bulls were collected using an electroejaculator. Semen samples were diluted with 8% VCO in Tris extender which contained different concentrations 0% (control), 4%, 8%, 12%, 16% and 20% egg yolk. The diluted semen samples were divided into two fractions: one was chilled and stored at 4°C until evaluation after 24, 72, and 144h; the second fraction was processed by chilling for 3h at 4°C to equilibrate, then packaged in 0.25ml straws and frozen and stored in liquid nitrogen at -196°C until evaluation after 7 and 14 days. Both chilled and frozen semen samples were then thawed at 37°C and assessed for general motility using computer-assisted semen analysis (CASA), viability, acrosome integrity, and morphology (eosin-nigrosin), membrane integrity (hypo-osmotic swelling test) and lipid peroxidation (thiobarbituric acid-reactive substances (TBARS)). The results indicate treatments with 8%, 12%, 16% and 20% egg yolk with 8% VCO had greater sperm quality (P<0.05) as compared with the control. The treatment with 20% egg yolk had the greatest sperm quality (P<0.05) among the treated groups for both chilled and frozen-thawed semen. In conclusion, the use of 8% VCO combined with 20% egg yolk in a Tris-based extender enhanced the values for chilled and frozen-thawed quality variables of bull sperm. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Substitution of egg yolk by a cyclodextrin-cholesterol complex allows a reduction of the glycerol concentration into the freezing medium of equine sperm.

    PubMed

    Blommaert, Didier; Franck, Thierry; Donnay, Isabelle; Lejeune, Jean-Philippe; Detilleux, Johann; Serteyn, Didier

    2016-02-01

    The aim of this work was to completely replace the egg yolk a classical diluent for freezing equine semen by a cyclodextrin-cholesterol complex. At the same time, the reduction in the glycerol content used for cryopreservation and the incubation time between sperm and the freezing media were evaluated. Horse ejaculates were frozen with four different freezing extenders: a frozen reference medium (IF) containing egg yolk and 2.5% glycerol and media without egg yolk but supplemented with 1.5 mg 2-hydroxypropyl-beta-cyclodextrin cholesterol (HPβCD-C) complex and containing either 1% (G1), 2% (G2) or 3% glycerol (G3). Three incubation times (90, 120 and 180 min) at 4 °C between the fresh semen and the different media were tested before freezing. Viability and motility analyses were performed with computer assisted semen analysis (CASA). Results showed that the freezing media containing the HPβCD-C complex with 1%, 2% and 3% glycerol significantly improve the 3 in vitro parameters of post thawing semen quality (viability, progressive and total mobilities) compared to IF. The best improvement of the parameters was obtained with G1 medium and the longest contact time. The substitution of egg yolk by HPβCD-C complex allows the decrease of protein charge of the medium while favouring the cholesterol supply to membrane spermatozoa offering it a better resistance to osmotic imbalance and a better tolerance to the glycerol toxicity. Our results highlight that the egg yolk of an extender for the freezing of horse semen can be completely substituted by HPβCD-C complex. Copyright © 2015. Published by Elsevier Inc.

  16. A Versatile Mounting Method for Long Term Imaging of Zebrafish Development.

    PubMed

    Hirsinger, Estelle; Steventon, Ben

    2017-01-26

    Zebrafish embryos offer an ideal experimental system to study complex morphogenetic processes due to their ease of accessibility and optical transparency. In particular, posterior body elongation is an essential process in embryonic development by which multiple tissue deformations act together to direct the formation of a large part of the body axis. In order to observe this process by long-term time-lapse imaging it is necessary to utilize a mounting technique that allows sufficient support to maintain samples in the correct orientation during transfer to the microscope and acquisition. In addition, the mounting must also provide sufficient freedom of movement for the outgrowth of the posterior body region without affecting its normal development. Finally, there must be a certain degree in versatility of the mounting method to allow imaging on diverse imaging set-ups. Here, we present a mounting technique for imaging the development of posterior body elongation in the zebrafish D. rerio. This technique involves mounting embryos such that the head and yolk sac regions are almost entirely included in agarose, while leaving out the posterior body region to elongate and develop normally. We will show how this can be adapted for upright, inverted and vertical light-sheet microscopy set-ups. While this protocol focuses on mounting embryos for imaging for the posterior body, it could easily be adapted for the live imaging of multiple aspects of zebrafish development.

  17. Microfluidic device for a rapid immobilization of zebrafish larvae in environmental scanning electron microscopy.

    PubMed

    Akagi, Jin; Zhu, Feng; Skommer, Joanna; Hall, Chris J; Crosier, Philip S; Cialkowski, Michal; Wlodkowic, Donald

    2015-03-01

    Small vertebrate model organisms have recently gained popularity as attractive experimental models that enhance our understanding of human tissue and organ development. Despite a large body of evidence using optical spectroscopy for the characterization of small model organism on chip-based devices, no attempts have been so far made to interface microfabricated technologies with environmental scanning electron microscopy (ESEM). Conventional scanning electron microscopy requires high vacuum environments and biological samples must be, therefore, submitted to many preparative procedures to dehydrate, fix, and subsequently stain the sample with gold-palladium deposition. This process is inherently low-throughput and can introduce many analytical artifacts. This work describes a proof-of-concept microfluidic chip-based system for immobilizing zebrafish larvae for ESEM imaging that is performed in a gaseous atmosphere, under low vacuum mode and without any need for sample staining protocols. The microfabricated technology provides a user-friendly and simple interface to perform ESEM imaging on zebrafish larvae. Presented lab-on-a-chip device was fabricated using a high-speed infrared laser micromachining in a biocompatible poly(methyl methacrylate) thermoplastic. It consisted of a reservoir with multiple semispherical microwells designed to hold the yolk of dechorionated zebrafish larvae. Immobilization of the larvae was achieved by a gentle suction generated during blotting of the medium. Trapping region allowed for multiple specimens to be conveniently positioned on the chip-based device within few minutes for ESEM imaging. © 2014 International Society for Advancement of Cytometry.

  18. Sodium benzoate induced developmental defects, oxidative stress and anxiety-like behaviour in zebrafish larva.

    PubMed

    Gaur, Himanshu; Purushothaman, Srinithi; Pullaguri, Narasimha; Bhargava, Yogesh; Bhargava, Anamika

    2018-07-20

    Sodium benzoate (SB) is a common food preservative. Its FDA described safety limit is 1000 ppm. Lately, increased use of SB has prompted investigations regarding its effects on biological systems. Data regarding toxicity of SB is divergent and controversial with studies reporting both harmful and beneficial effects. Therefore, we did a systematic dose dependent toxicity study of SB using zebrafish vertebrate animal model. We also investigated oxidative stress and anxiety-like behaviour in zebrafish larva treated with SB. Our results indicate that SB induced developmental (delayed hatching), morphological (pericardial edema, yolk sac edema and tail bending), biochemical (oxidative stress) and behavioural (anxiety-like behaviour) abnormalities in developing zebrafish larva. LC 50 of SB induced toxicity was approximately 400 ppm after 48 h of SB exposure. Our study strongly supports its harmful effects on vertebrates at increasing doses. Thus, we suggest caution in the excessive use of this preservative in processed and convenience foods. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Embryotoxicity of nitrophenols to the early life stages of zebrafish (Danio rerio).

    PubMed

    Ceylan, Zeynep; Şişman, Turgay; Yazıcı, Zehra; Altıkat, Aysun Özen

    2016-08-01

    The nitrophenols (NPs) are water-soluble compounds. These compounds pose a significant health threat since they are priority environmental pollutants. In this study, 2-Nitrophenol (2NP) and 2,4-dinitrophenol (DNP) were examined for embryo and early life stage toxicity in zebrafish (Danio rerio). Acute toxicity and teratogenicity of 2NP and DNP were tested for 4 days using zebrafish embryos. The typical lesions observed were no somite formation, incomplete eye and head development, tail curvature, weak pigmentation (≤48 hours postfertilization (hpf)), kyphosis, scoliosis, yolk sac deformity, and nonpigmentation (72 hpf). Also, embryo and larval mortality increased and hatching success decreased. The severity of abnormalities and mortalities were concentration- and compound-dependent. Of the compounds tested, 2,4-DNP was found to be highly toxic to the fish embryos following exposure. The median lethal concentrations and median effective concentrations for 2NP are 18.7 mg/L and 7.9 mg/L, respectively; the corresponding values for DNP are 9.65 mg/L and 3.05 mg/L for 48 h. The chorda deformity was the most sensitive endpoint measured. It is suggested that the embryotoxicity may be mediated by an oxidative phosphorylation uncoupling mechanism. This article is the first to describe the teratogenicity and embryotoxicity of two NPs to the early life stages of zebrafish. © The Author(s) 2014.

  20. Properties of low-fat, low-cholesterol egg yolk prepared by supercritical CO2 extraction.

    PubMed

    Bringe, N A

    1997-01-01

    A dry egg yolk ingredient called Eggcellent has 74% less fat and 90% less cholesterol than liquid egg yolks, when reconstituted on an equal protein basis. The phospholipids and proteins are retained, enabling the ingredient to have the taste and texturizing properties of fresh egg yolk. Using the new yolk, it is possible to significantly improve the acceptability of low-fat, low-cholesterol bakery products, scrambled eggs and mayonnaise dressings without losing nutritional claims. The structures and functional properties of egg yolk components and the conditions required to optimize their benefits in foods are reviewed. The lipoproteins of low-fat, low-cholesterol yolk have valuable properties as flavorants, texturizers, foaming agents, emulsifiers, antioxidants, colorants, and nutraceuticals.

  1. Effect of food additives on egg yolk gelation induced by freezing.

    PubMed

    Primacella, Monica; Fei, Tao; Acevedo, Nuria; Wang, Tong

    2018-10-15

    This study demonstrates technological advances in preventing yolk gelation during freezing and thawing. Gelation negatively affects yolk functionality in food formulation. Preventing gelation using 10% salt or sugar limits the application of the yolk. Novel food additives were tested to prevent gelation induced by freezing. Significant reduction (p < 0.05) in gel hardness of frozen-thawed yolk (45 h freezing at -20 °C) indicates that hydrolyzed carboxymethyl cellulose (HCMC), proline, and hydrolyzed egg white and yolk (HEW and HEY) are effective gelation inhibitors. The mechanisms in which these additives prevented gelation were further studied through measuring the changes in the amount of freezable water, lipoprotein particle size, and protein surface hydrophobicity. Overall, this study provides several alternatives of gelation inhibitor that have great potentials in replacing the use of salt or sugar in commercial operation of freezing egg yolk for shelf-life extension. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Cryopreservation of boar semen by egg yolk-based extenders containing lactose or fructose is better than sorbitol.

    PubMed

    Chanapiwat, Panida; Kaeoket, Kampon; Tummaruk, Padet

    2012-03-01

    The present study determined the effect of different types of sugars (lactose, fructose, glucose and sorbitol) used in egg yolk-based extender on the post-thawed boar semen quality. Twenty-two ejaculates from 6 fertility-proven Yorkshire boars were cryopreserved by liquid nitrogen vapor method. Sperm motility, viability, acrosome integrity and intact functional plasma membrane were determined at 0, 2 and 4 hr after thawing. It was found that the lactose-based extender resulted in a higher percentage of post-thawed sperm motility, viability, intact acrosome and functional plasma membrane than sorbitol-based extender (P<0.05) and fructose-based extender yielded a higher post-thawed sperm motility and viability than sorbitol-based extender (P<0.05). It could be concluded that sorbitol was not an effective sugar for the cryopreservation in boar semen.

  3. Oil exudation and histological structures of duck egg yolks during brining.

    PubMed

    Lai, K M; Chung, W H; Jao, C L; Hsu, K C

    2010-04-01

    Changes in oil exudation and histological structures of salted duck egg yolks during brining up to 5 wk were investigated. During brining, the salt contents of albumen, exterior yolk (hardened portion), and interior yolk (soft or liquid portion) gradually increased accompanied by slight decreases in moisture content. The hardening ratio of salted egg yolks increased rapidly to about 60% during the first week of brining and then reached 100% at the end of brining. After brining, part of the lipids in salted egg yolk became free due to the structural changes of low-density lipoprotein induced by dehydration and increase of salt content, and more free lipids in salted egg yolk were released after the cooking process. With the brining time increased up to 5 wk, the outer region of the cooked salted yolk gradually changed into dark brown, brown, orange, and then dark brown, whereas the center region changed into light yellow, yellow, dark yellow, and then yellow again. The microstructures of cooked salted egg yolks showed that the yolk spheres in the outer and middle regions retained their original shape, with some shrinking and being packed more loosely when brining time increased, and the exuded oil filled the space between the spheres. Furthermore, the yolk spheres in the center region transformed to a round shape but still showed granulation after 4 wk of brining, whereas they were mostly disrupted after 2 to 5 wk of brining. One of the most important characteristics of cooked salted egg yolks, gritty texture, contributed to oil exudation and granulated yolk spheres were observed at the brining time of 4 wk.

  4. The photoreceptive cells of the pineal gland in adult zebrafish (Danio rerio).

    PubMed

    Laurà, Rosaria; Magnoli, Domenico; Zichichi, Rosalia; Guerrera, Maria Cristina; De Carlos, Felix; Suárez, Alberto Álvarez; Abbate, Francesco; Ciriaco, Emilia; Vega, Jose Antonio; Germanà, Antonino

    2012-03-01

    The zebrafish pineal gland plays a fundamental role in the regulation of the circadian rhythm through the melatonin secretion. The pinealocytes, also called photoreceptive cells, are considered the morphofunctional unit of pineal gland. In literature, the anatomical features, the cellular characteristics, and the pinealocytes morphology of zebrafish pineal gland have not been previously described in detail. Therefore, this study was undertaken to analyze the structure and ultrastructure, as well as the immunohistochemical profile of the zebrafish pineal gland with particular reference to the pinealocytes. Here, we demonstrated, using RT-PCR, immunohistochemistry and transmission electron microscopy, the expression of the mRNA for rhodopsin in the pineal gland of zebrafish, as well as its cellular localization exclusively in the pinealocytes of adult zebrafish. Moreover, the ultrastructural observations demonstrated that the pinealocytes were constituted by an outer segment with numerous lamellar membranes, an inner segment with many mitochondria, and a basal pole with the synapses. Our results taken together demonstrated a central role of zebrafish pinealocytes in the control of pineal gland functions. Copyright © 2011 Wiley Periodicals, Inc.

  5. INDUCED AND SPONTANEOUS NEOPLASIA IN ZEBRAFISH.

    EPA Science Inventory

    To address the potential of zebrafish as a cancer model, it is important to determine the susceptibility of zebrafish to tumors, and to compare zebrafish tumors with human tumors. To determine whether the commonly-used germ line mutagen, ethylnitrosourea (ENU) induces tumors, we ...

  6. Super chilling enhances preservation of the freshness of salted egg yolk during long-term storage.

    PubMed

    Yanagisawa, T; Watanuki, C; Ariizumi, M; Shigematsu, Y; Kobayashi, H; Hasegawa, M; Watanabe, K

    2009-03-01

    Pasteurized egg yolk with 10% (w/w) salt was stored at 5, -5, -15, -20, and -30 degrees C for 1 to 6 mo, respectively. Changes in generation of volatiles of the stored samples (5 and -5 degrees C for 6 mo) were analyzed by SPME-GC-MS. Emulsifying properties of egg yolk stored at -5, -15, -20, and -30 degrees C for 1 mo, respectively, were also evaluated by measurement of emulsion particle diameters in model emulsions prepared with the yolk samples. In addition, structural changes in low-density lipoprotein (LDL) in the egg yolks dependent on storage conditions for 6 mo were evaluated by (31)P-NMR. Volatile compounds such as hexanal, 2-methylbutanal, and 3-methylbutanal increased in egg yolk during storage at 5 degrees C; however, volatile compounds hardly increased in any samples stored at -5 degrees C (super chilling). The mean emulsion particle diameter in super chilled egg yolk was significantly smaller than that in egg yolk stored at the other lower temperatures. In addition, the results of (31)P-NMR evaluation suggested that prevention of structural changes of LDL resulted in maintenance of emulsifying properties of egg yolk. Thus, these results indicate that super chilling is an effective means of preserving salted egg yolk during long-term storage.

  7. NAD+ Biosynthesis Ameliorates a Zebrafish Model of Muscular Dystrophy

    PubMed Central

    Goody, Michelle F.; Kelly, Meghan W.; Reynolds, Christine J.; Khalil, Andre; Crawford, Bryan D.; Henry, Clarissa A.

    2012-01-01

    Muscular dystrophies are common, currently incurable diseases. A subset of dystrophies result from genetic disruptions in complexes that attach muscle fibers to their surrounding extracellular matrix microenvironment. Cell-matrix adhesions are exquisite sensors of physiological conditions and mediate responses that allow cells to adapt to changing conditions. Thus, one approach towards finding targets for future therapeutic applications is to identify cell adhesion pathways that mediate these dynamic, adaptive responses in vivo. We find that nicotinamide riboside kinase 2b-mediated NAD+ biosynthesis, which functions as a small molecule agonist of muscle fiber-extracellular matrix adhesion, corrects dystrophic phenotypes in zebrafish lacking either a primary component of the dystrophin-glycoprotein complex or integrin alpha7. Exogenous NAD+ or a vitamin precursor to NAD+ reduces muscle fiber degeneration and results in significantly faster escape responses in dystrophic embryos. Overexpression of paxillin, a cell adhesion protein downstream of NAD+ in this novel cell adhesion pathway, reduces muscle degeneration in zebrafish with intact integrin receptors but does not improve motility. Activation of this pathway significantly increases organization of laminin, a major component of the extracellular matrix basement membrane. Our results indicate that the primary protective effects of NAD+ result from changes to the basement membrane, as a wild-type basement membrane is sufficient to increase resilience of dystrophic muscle fibers to damage. The surprising result that NAD+ supplementation ameliorates dystrophy in dystrophin-glycoprotein complex– or integrin alpha7–deficient zebrafish suggests the existence of an additional laminin receptor complex that anchors muscle fibers to the basement membrane. We find that integrin alpha6 participates in this pathway, but either integrin alpha7 or the dystrophin-glycoprotein complex is required in conjunction with integrin

  8. Maintenance of Zebrafish Lines at the European Zebrafish Resource Center.

    PubMed

    Geisler, Robert; Borel, Nadine; Ferg, Marco; Maier, Jana Viktoria; Strähle, Uwe

    2016-07-01

    We have established a European Zebrafish Resource Center (EZRC) at the KIT. This center not only maintains and distributes a large number of existing mutant and transgenic zebrafish lines but also gives zebrafish researchers access to screening services and technologies such as imaging and high-throughput sequencing, provided by the Institute of Toxicology and Genetics (ITG). The EZRC maintains and distributes the stock collection of the Nüsslein-Volhard laboratory, comprising over 2000 publicly released mutations, as frozen sperm samples. Within the framework of the ZF-HEALTH EU project, the EZRC distributes over 10,000 knockout mutations from the Sanger Institute (United Kingdom), as well as over 100 mutant and transgenic lines from other sources. In this article, we detail the measures we have taken to ensure the health of our fish, including hygiene, quarantine, and veterinary inspections.

  9. 3D MALDI Mass Spectrometry Imaging of a Single Cell: Spatial Mapping of Lipids in the Embryonic Development of Zebrafish

    SciT

    Dueñas, Maria Emilia; Essner, Jeffrey J.; Lee, Young Jin

    The zebrafish ( Danio rerio) has been widely used as a model vertebrate system to study lipid metabolism, the roles of lipids in diseases, and lipid dynamics in embryonic development. Here, we applied high-spatial resolution matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry imaging (MSI) to map and visualize the three-dimensional spatial distribution of phospholipid classes, phosphatidylcholine (PC), phosphatidylethanolamines (PE), and phosphatidylinositol (PI), in newly fertilized individual zebrafish embryos. This is the first time MALDI-MSI has been applied for three dimensional chemical imaging of a single cell. PC molecular species are present inside the yolk in addition to the blastodisc, while PE andmore » PI species are mostly absent in the yolk. Two-dimensional MSI was also studied for embryos at different cell stages (1-, 2-, 4-, 8-, and 16-cell stage) to investigate the localization changes of some lipids at various cell developmental stages. Lastly, four different normalization approaches were compared to find reliable relative quantification in 2D- and 3D- MALDI MSI data sets.« less

  10. 3D MALDI Mass Spectrometry Imaging of a Single Cell: Spatial Mapping of Lipids in the Embryonic Development of Zebrafish

    DOE PAGES

    Dueñas, Maria Emilia; Essner, Jeffrey J.; Lee, Young Jin

    2017-11-02

    The zebrafish ( Danio rerio) has been widely used as a model vertebrate system to study lipid metabolism, the roles of lipids in diseases, and lipid dynamics in embryonic development. Here, we applied high-spatial resolution matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry imaging (MSI) to map and visualize the three-dimensional spatial distribution of phospholipid classes, phosphatidylcholine (PC), phosphatidylethanolamines (PE), and phosphatidylinositol (PI), in newly fertilized individual zebrafish embryos. This is the first time MALDI-MSI has been applied for three dimensional chemical imaging of a single cell. PC molecular species are present inside the yolk in addition to the blastodisc, while PE andmore » PI species are mostly absent in the yolk. Two-dimensional MSI was also studied for embryos at different cell stages (1-, 2-, 4-, 8-, and 16-cell stage) to investigate the localization changes of some lipids at various cell developmental stages. Lastly, four different normalization approaches were compared to find reliable relative quantification in 2D- and 3D- MALDI MSI data sets.« less

  11. In vivo physiological recording from the lateral line of juvenile zebrafish

    PubMed Central

    Olt, Jennifer; Allen, Claire E.

    2016-01-01

    Key points Zebrafish provide a unique opportunity to investigate in vivo sensory transduction in mature hair cells.We have developed a method for studying the biophysical properties of mature hair cells from the lateral line of juvenile zebrafish.The method involves application of the anaesthetic benzocaine and intubation to maintain ventilation and oxygenation through the gills.The same approach could be used for in vivo functional studies in other sensory and non‐sensory systems from juvenile and adult zebrafish. Abstract Hair cells are sensory receptors responsible for transducing auditory and vestibular information into electrical signals, which are then transmitted with remarkable precision to afferent neurons. The zebrafish lateral line is emerging as an excellent in vivo model for genetic and physiological analysis of hair cells and neurons. However, research has been limited to larval stages because zebrafish become protected from the time of independent feeding under European law (from 5.2 days post‐fertilization (dpf) at 28.5°C). In larval zebrafish, the functional properties of most of hair cells, as well as those of other excitable cells, are still immature. We have developed an experimental protocol to record electrophysiological properties from hair cells of the lateral line in juvenile zebrafish. We found that the anaesthetic benzocaine at 50 mg l−1 was an effective and safe anaesthetic to use on juvenile zebrafish. Concentrations up to 300 mg l−1 did not affect the electrical properties or synaptic vesicle release of juvenile hair cells, unlike the commonly used anaesthetic MS‐222, which reduces the size of basolateral membrane K+ currents. Additionally, we implemented a method to maintain gill movement, and as such respiration and blood oxygenation, via the intubation of > 21 dpf zebrafish. The combination of benzocaine and intubation provides an experimental platform to investigate the physiology of mature hair cells from live

  12. In vivo physiological recording from the lateral line of juvenile zebrafish.

    PubMed

    Olt, Jennifer; Allen, Claire E; Marcotti, Walter

    2016-10-01

    Zebrafish provide a unique opportunity to investigate in vivo sensory transduction in mature hair cells. We have developed a method for studying the biophysical properties of mature hair cells from the lateral line of juvenile zebrafish. The method involves application of the anaesthetic benzocaine and intubation to maintain ventilation and oxygenation through the gills. The same approach could be used for in vivo functional studies in other sensory and non-sensory systems from juvenile and adult zebrafish. Hair cells are sensory receptors responsible for transducing auditory and vestibular information into electrical signals, which are then transmitted with remarkable precision to afferent neurons. The zebrafish lateral line is emerging as an excellent in vivo model for genetic and physiological analysis of hair cells and neurons. However, research has been limited to larval stages because zebrafish become protected from the time of independent feeding under European law (from 5.2 days post-fertilization (dpf) at 28.5°C). In larval zebrafish, the functional properties of most of hair cells, as well as those of other excitable cells, are still immature. We have developed an experimental protocol to record electrophysiological properties from hair cells of the lateral line in juvenile zebrafish. We found that the anaesthetic benzocaine at 50 mg l(-1) was an effective and safe anaesthetic to use on juvenile zebrafish. Concentrations up to 300 mg l(-1) did not affect the electrical properties or synaptic vesicle release of juvenile hair cells, unlike the commonly used anaesthetic MS-222, which reduces the size of basolateral membrane K(+) currents. Additionally, we implemented a method to maintain gill movement, and as such respiration and blood oxygenation, via the intubation of > 21 dpf zebrafish. The combination of benzocaine and intubation provides an experimental platform to investigate the physiology of mature hair cells from live zebrafish. More

  13. Requirement of zebrafish pcdh10a and pcdh10b in melanocyte precursor migration.

    PubMed

    Williams, Jason S; Hsu, Jessica Y; Rossi, Christy Cortez; Artinger, Kristin Bruk

    2018-03-29

    Melanocytes derive from neural crest cells, which are a highly migratory population of cells that play an important role in pigmentation of the skin and epidermal appendages. In most vertebrates, melanocyte precursor cells migrate solely along the dorsolateral pathway to populate the skin. However, zebrafish melanocyte precursors also migrate along the ventromedial pathway, in route to the yolk, where they interact with other neural crest derivative populations. Here, we demonstrate the requirement for zebrafish paralogs pcdh10a and pcdh10b in zebrafish melanocyte precursor migration. pcdh10a and pcdh10b are expressed in a subset of melanocyte precursor and somatic cells respectively, and knockdown and TALEN mediated gene disruption of pcdh10a results in aberrant migration of melanocyte precursors resulting in fully melanized melanocytes that differentiate precociously in the ventromedial pathway. Live cell imaging analysis demonstrates that loss of pchd10a results in a reduction of directed cell migration of melanocyte precursors, caused by both increased adhesion and a loss of cell-cell contact with other migratory neural crest cells. Also, we determined that the paralog pcdh10b is upregulated and can compensate for the genetic loss of pcdh10a. Disruption of pcdh10b alone by CRISPR mutagenesis results in somite defects, while the loss of both paralogs results in enhanced migratory melanocyte precursor phenotype and embryonic lethality. These results reveal a novel role for pcdh10a and pcdh10b in zebrafish melanocyte precursor migration and suggest that pcdh10 paralogs potentially interact for proper transient migration along the ventromedial pathway. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Neurochemical measurements in the zebrafish brain

    PubMed Central

    Jones, Lauren J.; McCutcheon, James E.; Young, Andrew M. J.; Norton, William H. J.

    2015-01-01

    The zebrafish is an ideal model organism for behavioral genetics and neuroscience. The high conservation of genes and neurotransmitter pathways between zebrafish and other vertebrates permits the translation of research between species. Zebrafish behavior can be studied at both larval and adult stages and recent research has begun to establish zebrafish models for human disease. Fast scan cyclic voltammetry (FSCV) is an electrochemical technique that permits the detection of neurotransmitter release and reuptake. In this study we have used in vitro FSCV to measure the release of analytes in the adult zebrafish telencephalon. We compare different stimulation methods and present a characterization of neurochemical changes in the wild-type zebrafish brain. This study represents the first FSCV recordings in zebrafish, thus paving the way for neurochemical analysis of the fish brain. PMID:26441575

  15. Genomic Approaches to Zebrafish Cancer

    PubMed Central

    2017-01-01

    The zebrafish has emerged as an important model for studying cancer biology. Identification of DNA, RNA and chromatin abnormalities can give profound insight into the mechanisms of tumorigenesis and the there are many techniques for analyzing the genomes of these tumors. Here, I present an overview of the available technologies for analyzing tumor genomes in the zebrafish, including array based methods as well as next-generation sequencing technologies. I also discuss the ways in which zebrafish tumor genomes can be compared to human genomes using cross-species oncogenomics, which act to filter genomic noise and ultimately uncover central drivers of malignancy. Finally, I discuss downstream analytic tools, including network analysis, that can help to organize the alterations into coherent biological frameworks that can then be investigated further. PMID:27165352

  16. New frontiers for zebrafish management.

    PubMed

    Lawrence, C

    2016-01-01

    The zebrafish (Danio rerio) is a preeminent model organism with a wide and expanding utility for numerous scientific disciplines. The same features that once endeared this small freshwater minnow to developmental biologists combined with its relatively high genetic similarity to mammals and the advent of new, more efficient methods for genome editing are now helping to spur expanded growth in its usage in various fields, including toxicology, drug discovery, transplant biology, disease modeling, and even aquaculture. Continued maturation and adoption of the zebrafish model system in these and other fields of science will require that methods and approaches for husbandry and management of these fish in controlled settings be refined and improved to the extent that, ultimately, zebrafish research becomes more reproducible, defined, cost-effective, and accessible to the masses. Knowledge and technology transfer from laboratory animal science and commercial aquaculture will be a necessary part of this development. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Mayo Clinic Zebrafish Facility Overview.

    PubMed

    Leveque, Ryan E; Clark, Karl J; Ekker, Stephen C

    2016-07-01

    The zebrafish (Danio rerio) is a premier nonmammalian vertebrate model organism. This small aquatic fish is utilized in multiple disciplines in the Mayo Clinic community and by many laboratories around the world because of its biological similarity to humans, its advanced molecular genetics, the elucidation of its genome sequence, and the ever-expanding and outstanding new biological tools now available to the zebrafish researcher. The Mayo Clinic Zebrafish Facility (MCZF) houses ∼2,000 tanks annotated using an in-house, Internet cloud-based bar-coding system tied to our established zfishbook.org web infrastructure. Paramecia are the primary food source for larval fish rearing, using a simplified culture protocol described herein. The MCZF supports the specific ongoing research in a variety of laboratories, while also serving as a local hub for new scientists as they learn to tap into the potential of this model system for understanding normal development, disease, and as models of health.

  18. Phosphatidylcholine from "Healthful" Egg Yolk Varieties: An Organic Laboratory Experience

    NASA Astrophysics Data System (ADS)

    Hodges, Linda C.

    1995-12-01

    I have added an investigative element to a popular undergraduate experiment. the characterization of phosphatidylcholine (PC) from egg yolks. Varieties of eggs are commercially available which have been obtained from chickens fed a diet containing no animal fat. Presumably, less saturated fat in the diet of the chickens could be reflected in the fatty acid composition of various classes of biological lipids, including phospholipids, in the eggs from these chickens. PC is extracted using conventional methods, the extract is further purified by chromatography on silicic acid, and the column fractions are assayed for the presence and purity of PC by TLC. Fractions containing pure PC are pooled, concentrated, hydrolyzed, and esterified to obtain the fatty acid methyl esters (FAME) which are identified by GLC. Comparing FAMEs derived from PC of yolks of regular eggs to those obtained from the other special brands adds a novel twist to the students' work and generates greater student interest and involvement in both the interpretation of data than a simple isolation of a biological compound alone evokes.

  19. Response of amphibian egg non-yolk cytoplasm to gravity orientation

    NASA Technical Reports Server (NTRS)

    Smith, R. C.; Neff, A. W.; Malacinski, G. M.

    1985-01-01

    In order to study amphibian egg cytoplasmic organization and egg symmetrization at the molecular level, a library of seventeen monoclonal antibodies (MoAbs) against Xenopus laevis non-yolk egg proteins was produced. Several of these MoAbs react with non-yolk cytoplasmic antigens which are unevenly distributed in the fertile Xenopus egg.

  20. 9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Procedures for preparing egg yolk... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic... chapter. (a) Under the supervision of an Authorized Agent or State Inspector, the eggs which are used in...

  1. 9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

  2. 9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

  3. 9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

  4. 9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Procedures for preparing egg yolk samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic...

  5. Developmental Toxicity of Zinc Oxide Nanoparticles to Zebrafish (Danio rerio): A Transcriptomic Analysis

    PubMed Central

    Choi, Jin Soo; Kim, Ryeo-Ok; Yoon, Seokjoo

    2016-01-01

    Zinc oxide nanoparticles (ZnO NPs) are being utilized in an increasing number of fields and commercial applications. While their general toxicity and associated oxidative stress have been extensively studied, the toxicological pathways that they induce in developmental stages are still largely unknown. In this study, the developmental toxicity of ZnO NPs to embryonic/larval zebrafish was investigated. The transcriptional expression profiles induced by ZnO NPs were also investigated to ascertain novel genomic responses related to their specific toxicity pathway. Zebrafish embryos were exposed to 0.01, 0.1, 1, and 10 mg/L ZnO NPs for 96 h post-fertilization. The toxicity of ZnO NPs, based on their Zn concentration, was quite similar to that in embryonic/larval zebrafish exposed to corresponding ZnSO4 concentrations. Pericardial edema and yolk-sac edema were the principal malformations induced by ZnO NPs. Gene-expression profiling using microarrays demonstrated 689 genes that were differentially regulated (fold change >1.5) following exposure to ZnO NPs (498 upregulated, 191 downregulated). Several genes that were differentially regulated following ZnO NP exposure shared similar biological pathways with those observed with ZnSO4 exposure, but six genes (aicda, cyb5d1, edar, intl2, ogfrl2 and tnfsf13b) associated with inflammation and the immune system responded specifically to ZnO NPs (either in the opposite direction or were unchanged in ZnSO4 exposure). Real-time reverse-transcription quantitative polymerase chain reaction confirmed that the responses of these genes to ZnO NPs were significantly different from their response to ZnSO4 exposure. ZnO NPs may affect genes related to inflammation and the immune system, resulting in yolk-sac edema and pericardia edema in embryonic/larval developmental stages. These results will assist in elucidating the mechanisms of toxicity of ZnO NPs during development of zebrafish. PMID:27504894

  6. Gene Trapping Using Gal4 in Zebrafish

    PubMed Central

    Balciuniene, Jorune; Balciunas, Darius

    2013-01-01

    Large clutch size and external development of optically transparent embryos make zebrafish an exceptional vertebrate model system for in vivo insertional mutagenesis using fluorescent reporters to tag expression of mutated genes. Several laboratories have constructed and tested enhancer- and gene-trap vectors in zebrafish, using fluorescent proteins, Gal4- and lexA- based transcriptional activators as reporters 1-7. These vectors had two potential drawbacks: suboptimal stringency (e.g. lack of ability to differentiate between enhancer- and gene-trap events) and low mutagenicity (e.g. integrations into genes rarely produced null alleles). Gene Breaking Transposon (GBTs) were developed to address these drawbacks 8-10. We have modified one of the first GBT vectors, GBT-R15, for use with Gal4-VP16 as the primary gene trap reporter and added UAS:eGFP as the secondary reporter for direct detection of gene trap events. Application of Gal4-VP16 as the primary gene trap reporter provides two main advantages. First, it increases sensitivity for genes expressed at low expression levels. Second, it enables researchers to use gene trap lines as Gal4 drivers to direct expression of other transgenes in very specific tissues. This is especially pertinent for genes with non-essential or redundant functions, where gene trap integration may not result in overt phenotypes. The disadvantage of using Gal4-VP16 as the primary gene trap reporter is that genes coding for proteins with N-terminal signal sequences are not amenable to trapping, as the resulting Gal4-VP16 fusion proteins are unlikely to be able to enter the nucleus and activate transcription. Importantly, the use of Gal4-VP16 does not pre-select for nuclear proteins: we recovered gene trap mutations in genes encoding proteins which function in the nucleus, the cytoplasm and the plasma membrane. PMID:24121167

  7. Toxicity Evaluation of Pig Slurry Using Luminescent Bacteria and Zebrafish

    PubMed Central

    Chen, Wenyan; Cai, Qiang; Zhao, Yuan; Zheng, Guojuan; Liang, Yuting

    2014-01-01

    Biogas slurry has become a serious pollution problem and anaerobic digestion is widely applied to pig manure treatment for environmental protection and energy recovery. To evaluate environmental risk of the emission of biogas slurry, luminescent bacteria (Vibrio fischeri), larvae and embryos of zebrafish (Danio rerio) were used to detect the acute and development toxicity of digested and post-treated slurry. Then the ability of treatment process was evaluated. The results showed that digested slurry displayed strong toxicity to both zebrafish and luminescent bacteria, while the EC50 for luminescent bacteria and the LC50 for larvae were only 6.81% (v/v) and 1.95% (v/v) respectively, and embryonic development was inhibited at just 1% (v/v). Slurry still maintained a high level of toxicity although it had been treated by membrane bioreactor (MBR), while the LC50 of larvae was 75.23% (v/v) and there was a little effect on the development of embryos and V. fischeri; the results also revealed that the zebrafish larvae are more sensitive than embryos and luminescent bacteria to pig slurry. Finally, we also found the toxicity removal rate was higher than 90% after the treatment of MBR according to toxicity tests. In conclusion, further treatment should be used in pig slurry disposal or reused of final effluent. PMID:24995598

  8. Developmental Localization of Nephrin in Zebrafish and Medaka Pronephric Glomerulus

    PubMed Central

    Ichimura, Koichiro; Fukuyo, Yayoi; Nakamura, Tomomi; Powell, Rebecca; Sakai, Tatsuo; Janknecht, Ralf

    2013-01-01

    Slit diaphragm (SD) is a highly specialized intercellular junction between podocyte foot processes and plays a crucial role in the formation of the filtration barrier. In this study, we examined the developmental localization of Nephrin, an essential component of SD, in the pronephric glomerulus of zebrafish and medaka. In the mature glomerulus of both fish, Nephrin is localized along the glomerular basement membrane as seen in mammals, indicating that Nephrin is localized at the SD. Interestingly, Nephrin was detected already in immature podocytes before the SD and foot processes started to form in both fish. Nephrin was localized along the cell surface of immature podocytes but as different localization patterns. In zebrafish, Nephrin signal bordered the lateral membrane of podocytes, which were columnar in shape, as in rat immature podocytes. However, in medaka immature podocytes, Nephrin was localized in a punctate pattern among podocyte cell bodies. These findings suggest that Nephrin needs to be integrated to the membrane before the formation of the SD and then moves to the proper site to form the SD. Furthermore, a podocyte-specific marker, such as Nephrin, should be a useful tool for the future analysis of pronephric glomerular development in fish mutants and morphants. PMID:23324868

  9. Validation of visualized transgenic zebrafish as a high throughput model to assay bradycardia related cardio toxicity risk candidates.

    PubMed

    Wen, Dingsheng; Liu, Aiming; Chen, Feng; Yang, Julin; Dai, Renke

    2012-10-01

    Drug-induced QT prolongation usually leads to torsade de pointes (TdP), thus for drugs in the early phase of development this risk should be evaluated. In the present study, we demonstrated a visualized transgenic zebrafish as an in vivo high-throughput model to assay the risk of drug-induced QT prolongation. Zebrafish larvae 48 h post-fertilization expressing green fluorescent protein in myocardium were incubated with compounds reported to induce QT prolongation or block the human ether-a-go-go-related gene (hERG) K⁺ current. The compounds sotalol, indapaminde, erythromycin, ofoxacin, levofloxacin, sparfloxacin and roxithromycin were additionally administrated by microinjection into the larvae yolk sac. The ventricle heart rate was recorded using the automatic monitoring system after incubation or microinjection. As a result, 14 out of 16 compounds inducing dog QT prolongation caused bradycardia in zebrafish. A similar result was observed with 21 out of 26 compounds which block hERG current. Among the 30 compounds which induced human QT prolongation, 25 caused bradycardia in this model. Thus, the risk of compounds causing bradycardia in this transgenic zebrafish correlated with that causing QT prolongation and hERG K⁺ current blockage in established models. The tendency that high logP values lead to high risk of QT prolongation in this model was indicated, and non-sensitivity of this model to antibacterial agents was revealed. These data suggest application of this transgenic zebrafish as a high-throughput model to screen QT prolongation-related cardio toxicity of the drug candidates. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Assessment of Jatropha curcas L. biodiesel seed cake toxicity using the zebrafish (Danio rerio) embryo toxicity (ZFET) test.

    PubMed

    Hallare, Arnold V; Ruiz, Paulo Lorenzo S; Cariño, J C Earl D

    2014-05-01

    Consequent to the growing demand for alternative sources of energy, the seeds from Jatropha curcas remain to be the favorite for biodiesel production. However, a significant volume of the residual organic mass (seed cake) is produced during the extraction process, which raises concerns on safe waste disposal. In the present study, we assessed the toxicity of J. curcas seed cake using the zebrafish (Danio rerio) embryotoxicity test. Within 1-h post-fertilization (hpf), the fertilized eggs were exposed to five mass concentrations of J. curcas seed cake and were followed through 24, 48, and 72 hpf. Toxicity was evaluated based on lethal endpoints induced on zebrafish embryos namely egg coagulation, non-formation of somites, and non-detachment of tail. The lowest concentration tested, 1 g/L, was not able to elicit toxicity on embryos whereas 100 % mortality (based also on lethal endpoints) was recorded at the highest concentration at 2.15 g/L. The computed LC50 for the J. curcas seed cake was 1.61 g/L. No further increase in mortality was observed in the succeeding time points (48 and 72 hpf) indicating that J. curcas seed cake exerted acute toxicity on zebrafish embryos. Sublethal endpoints (yolk sac and pericardial edema) were noted at 72 hpf in zebrafish embryos exposed to higher concentrations. The observed lethal endpoints induced on zebrafish embryos were discussed in relation to the active principles, notably, phorbol esters that have remained in the seed cake even after extraction.

  11. Zebrafish sex: a complicated affair

    PubMed Central

    Liew, Woei Chang

    2014-01-01

    In this review, we provide a detailed overview of studies on the elusive sex determination (SD) and gonad differentiation mechanisms of zebrafish (Danio rerio). We show that the data obtained from most studies are compatible with polygenic sex determination (PSD), where the decision is made by the allelic combinations of several loci. These loci are typically dispersed throughout the genome, but in some teleost species a few of them might be located on a preferential pair of (sex) chromosomes. The PSD system has a much higher level of variation of SD genotypes both at the level of gametes and the sexual genotype of individuals, than that of the chromosomal sex determination systems. The early sexual development of zebrafish males is a complicated process, as they first develop a ‘juvenile ovary’, that later undergoes a transformation to give way to a testis. To date, three major developmental pathways were shown to be involved with gonad differentiation through the modulation of programmed cell death. In our opinion, there are more pathways participating in the regulation of zebrafish gonad differentiation/transformation. Introduction of additional powerful large-scale genomic approaches into the analysis of zebrafish reproduction will result in further deepening of our knowledge as well as identification of additional pathways and genes associated with these processes in the near future. PMID:24148942

  12. Knockdown of prothrombin in zebrafish.

    PubMed

    Day, Kenneth; Krishnegowda, Naveen; Jagadeeswaran, Pudur

    2004-01-01

    Thrombin is a serine protease generated from its zymogen, prothrombin, and plays a central role in the coagulation cascade. It is also important for mammalian development. The zebrafish has now been established as an excellent genetic model for studies on mammalian hemostasis and development. In this report, we used prothrombin-specific antisense morpholinos to knock down the levels of prothrombin to characterize the effects of prothrombin deficiency in the zebrafish embryo. Prothrombin morpholino-injected zebrafish embryos yielded an early phenotype exhibiting severe abnormalities that later showed occasional bleeding. In a second late phenotype, the embryos had no observable morphological abnormalities in early stages, but showed occasional bleeding at later stages. These phenotypes resembled characteristics shown by prothrombin knockout mice. Laser-induced vascular injury on some of the normal appearing phenotypic larvae showed a prolonged time to occlusion, and recombinant zebrafish prothrombin injected into these larvae restored a normal time to occlusion thus showing the specificity of the morpholino effect. The system developed here should be useful for investigation of the role of thrombin in vertebrate development.

  13. Contextual fear conditioning in zebrafish.

    PubMed

    Kenney, Justin W; Scott, Ian C; Josselyn, Sheena A; Frankland, Paul W

    2017-10-01

    Zebrafish are a genetically tractable vertebrate that hold considerable promise for elucidating the molecular basis of behavior. Although numerous recent advances have been made in the ability to precisely manipulate the zebrafish genome, much less is known about many aspects of learning and memory in adult fish. Here, we describe the development of a contextual fear conditioning paradigm using an electric shock as the aversive stimulus. We find that contextual fear conditioning is modulated by shock intensity, prevented by an established amnestic agent (MK-801), lasts at least 14 d, and exhibits extinction. Furthermore, fish of various background strains (AB, Tu, and TL) are able to acquire fear conditioning, but differ in fear extinction rates. Taken together, we find that contextual fear conditioning in zebrafish shares many similarities with the widely used contextual fear conditioning paradigm in rodents. Combined with the amenability of genetic manipulation in zebrafish, we anticipate that our paradigm will prove to be a useful complementary system in which to examine the molecular basis of vertebrate learning and memory. © 2017 Kenney et al.; Published by Cold Spring Harbor Laboratory Press.

  14. Using fluorescent lipids in live zebrafish larvae: From imaging whole animal physiology to subcellular lipid trafficking.

    PubMed

    Anderson, J L; Carten, J D; Farber, S A

    2016-01-01

    Lipids serve essential functions in cells as signaling molecules, membrane components, and sources of energy. Defects in lipid metabolism are implicated in a number of pandemic human diseases, including diabetes, obesity, and hypercholesterolemia. Many aspects of how fatty acids and cholesterol are absorbed and processed by intestinal cells remain unclear and present a hurdle to developing approaches for disease prevention and treatment. Numerous studies have shown that the zebrafish is an excellent model for vertebrate lipid metabolism. In this chapter, we review commercially available fluorescent lipids that can be deployed in live zebrafish to better understand lipid signaling and metabolism. In this chapter, we present criteria one should consider when selecting specific fluorescent lipids for the study of digestive physiology or lipid metabolism in larval zebrafish. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Effect of different dietary energy and protein sources on antioxidant status, fresh yolk fatty acid profile and microstructure of salted yolks in laying ducks.

    PubMed

    Ruan, D; Hu, Y J; Fouad, A M; Lin, C X; Xu, Z P; Chen, W; Fan, Q L; Xia, W G; Wang, S; Wang, Y; Yang, L; Zheng, C T

    2018-01-08

    The study investigated whether different dietary energy and protein sources affect laying performance, antioxidant status, fresh yolk fatty acid profile and quality of salted yolks in laying ducks. In all, 360 19-week-old Longyan ducks were randomly assigned to four diets in a factorial arrangement (2×2). The four diets consisted of two energy sources, corn (CO) or sorghum (SO) and two protein sources, soybean meal (SM) and rapeseed meal with corn distillers dried grains with solubles (RMD), and each treatment contained six replicates of 15 birds each. The experimental diets were isocaloric (metabolizable energy, 10.84 MJ/kg) and isonitrogenous (CP, 17%). The results showed that egg production, average egg weight, egg mass and feed conversion ratio were not affected by diets (P>0.05). Plasma contents of reduced glutathione (GSH), GSH/oxidized glutathione and total antioxidant capacity were lower (P<0.05) in ducks fed the RMD diets compared with those fed SM diets with a substantial increase (P=0.006) in plasma content of malondialdehyde (MDA). Egg yolks from ducks fed SO diets had higher proportions of polyunsaturated fatty acids (PUFA) and lower saturated and monounsaturated fatty acids compared with CO diets (P<0.001). Similarly, ducks fed RMD diets had a higher content of PUFA and n-6/n-3 ratio in fresh yolks (P<0.001), and increased salted yolk MDA, carbonylated proteins content and incidence of hard salted yolks (P<0.05) compared with SM diets. Scanning electron microscopy showed that salted yolks contained rougher polyhedral granules and fewer fat droplets, and were surrounded with a layer of bunchy fibers in ducks fed SO+RMD than those fed CO+SM diet. In conclusion, the current study showed that feeding laying ducks with diets containing SO or RMD reduced antioxidant capacity and increased egg yolk concentrations of PUFA. It appeared that egg yolks from ducks fed these diets were more sensitive to lipid peroxidation and protein oxidation during salting, and

  16. TSH Receptor Function Is Required for Normal Thyroid Differentiation in Zebrafish

    PubMed Central

    Opitz, Robert; Maquet, Emilie; Zoenen, Maxime; Dadhich, Rajesh

    2011-01-01

    TSH is the primary physiological regulator of thyroid gland function. The effects of TSH on thyroid cells are mediated via activation of its membrane receptor [TSH receptor (TSHR)]. In this study, we examined functional thyroid differentiation in zebrafish and characterized the role of TSHR signaling during thyroid organogenesis. Cloning of a cDNA encoding zebrafish Tshr showed conservation of primary structure and functional properties between zebrafish and mammalian TSHR. In situ hybridization confirmed that the thyroid is the major site of tshr expression during zebrafish development. In addition, we identified tpo, iyd, duox, and duoxa as novel thyroid differentiation markers in zebrafish. Temporal analyses of differentiation marker expression demonstrated the induction of an early thyroid differentiation program along with thyroid budding, followed by a delayed onset of duox and duoxa expression coincident with thyroid hormone synthesis. Furthermore, comparative analyses in mouse and zebrafish revealed for the first time a thyroid-enriched expression of cell death regulators of the B-cell lymphoma 2 family during early thyroid morphogenesis. Knockdown of tshr function by morpholino microinjection into embryos did not affect early thyroid morphogenesis but caused defects in later functional differentiation. The thyroid phenotype observed in tshr morphants at later stages comprised a reduction in number and size of functional follicles, down-regulation of differentiation markers, as well as reduced thyroid transcription factor expression. A comparison of our results with phenotypes observed in mouse models of defective TSHR and cAMP signaling highlights the value of zebrafish as a model to enhance the understanding of functional differentiation in the vertebrate thyroid. PMID:21737742

  17. Effect of Freezing, Thermal Pasteurization, and Hydrostatic Pressure on Fractionation and Folate Recovery in Egg Yolk.

    PubMed

    Naderi, Nassim; Pouliot, Yves; House, James D; Doyen, Alain

    2017-09-06

    In this study, the impact of pasteurization and freezing of raw material, as performed at a commercial scale, on egg yolk fractionation and folate recovery was assessed. Freezing induced denaturation of the lipoproteins in egg yolk, which prevented further fractionation of the yolk. Thermal pasteurization of egg yolk at 61.1 °C for 3.5 min as well as high hydrostatic pressure (HHP) treatment (400 MPa for 5 min) did not change (p < 0.05) the composition of egg yolk or yolk fractions after their recovery by centrifugation. Expressed as dry matter, folate in pasteurized yolk was measured to be 599 μg/100 g, while its concentration reached 1969.7 μg/100 g for pasteurized granule and 1902.5 μg/100 g for HHP-treated granule. Folate was not detected in plasma, emphasizing the complete separation of yolk folate into granule. Further, we studied the effect of HHP on different dilutions of egg yolk, which were then fractionated. Egg yolk was diluted with water at different concentrations (0.1, 1.0, 10, 25, and 50%), HHP-treated at 400 MPa for 5 min, and centrifuged. Characterization of the compositions of the separated granule and plasma followed. Folate was stable under the HHP conditions used. However, HHP caused separation of folate from the yolk structure into water-soluble plasma. After HHP processing, the amount of folate detected in the plasma fraction was significantly (p < 0.05) higher (1434.9 μg/100 g) in the 25% diluted samples but was significantly (p < 0.05) lower in HHP-treated granule samples. Native sodium dodecyl sulfate-polyacrylamide gel electrophoresis results showed that phosvitin, α-livetin, and apovitellenin VIa were the proteins most resistant to HHP. This study confirms that dilution of egg yolk before HHP treatment can significantly (p < 0.05) change the composition of granule and plasma fractions after centrifugal fractionation of egg yolk.

  18. Using life-histories to predict and interpret variability in yolk hormones.

    PubMed

    Love, O P; Gilchrist, H G; Bêty, J; Wynne-Edwards, K E; Berzins, L; Williams, T D

    2009-09-01

    Variation in yolk hormones is assumed to provide the plasticity necessary for mothers to individually optimize reproductive decisions via changes in offspring phenotype, the benefit being to maximise fitness. However, rather than routinely expecting adaptive variation within all species, the pattern and magnitude of yolk hormone deposition should theoretically relate to variation in life-histories. Here we present data on intra-clutch variation in yolk corticosterone in three species along a developmental continuum (European starling (Sturnus vulgaris): fully altricial; black guillemot (Cepphus grylle): semi-precocial; common eider (Somateria mollissima): fully precocial) to examine how and why variation in life-histories might relate to the evolution of variation in yolk steroids. Starlings and guillemots showed a significant increase in yolk corticosterone across the laying sequence; however, we found no pattern within eider clutches. Moreover, starlings showed the largest difference (94.6%) in yolk corticosterone between first- and last-laid eggs, whereas guillemots showed a moderate difference (58.9%). Despite these general species-specific patterns, individuals showed marked variation in the intra-clutch patterns of yolk corticosterone within each species indicating potential differences in intra-clutch flexibility among females. It is well documented that exposure to elevated yolk glucocorticoids reduces offspring quality at birth/hatching in many taxa and it has therefore been proposed that elevated yolk levels may modulate offspring competition and/or facilitate brood reduction under harsh conditions in birds. Our data suggests that intra-clutch variation in yolk corticosterone has the potential to act as an adaptive maternal effect in species where modulation of competition between nest-bound offspring would benefit mothers (starlings and guillemots). However, in precocial species where mothers would not benefit from a modulation of offspring quality

  19. Comparative study of P19 EC stem cell differentiation in between conventional hanging drop and the zebrafish chorion as a bio-derived material.

    PubMed

    Dae Seok Na; Lee, Hwang; Sun Uk Kim; Chang Nam Hwang; Sang Ho Lee; Ji Yoon Kang; Jai Kyeong Kim; James Jungho Pak

    2008-07-01

    Various materials including glass and polymers have been widely used for stem cell culture due to their biocompatibility. However, the roles of these materials are fundamentally limited because they cannot realize or imitate the complex biological functions of living tissues, except in very simple cases. Here, the development of a bio-derived material suitable for stem cell culture and improvement of differentiation efficiency to specific cell lineages with no stimulating agents by using a chorion obtained from a fertilized zebrafish egg through the removal of the yolk and embryonic cell mass from the egg is reported. Mouse P19 EC stem cells introduced into the empty chorion form a uniform embryoid body (EB) without addition of any inducing agent. It is demonstrated that the zebrafish chorion with nanopores improves efficiencies greatly in the EB formation, cell proliferation, and lineage-specific differentiations compared to those of the conventional hanging drop culture method.

  20. Behavioural fever in zebrafish larvae.

    PubMed

    Rey, Sonia; Moiche, Visila; Boltaña, Sebastian; Teles, Mariana; MacKenzie, Simon

    2017-02-01

    Behavioural fever has been reported in different species of mobile ectotherms including the zebrafish, Danio rerio, in response to exogenous pyrogens. In this study we report, to our knowledge for the first time, upon the ontogenic onset of behavioural fever in zebrafish (Danio rerio) larvae. For this, zebrafish larvae (from first feeding to juveniles) were placed in a continuous thermal gradient providing the opportunity to select their preferred temperature. The novel thermal preference aquarium was based upon a continuous vertical column system and allows for non-invasive observation of larvae vertical distribution under isothermal (T R at 28 °C) and thermal gradient conditions (T CH : 28-32 °C). Larval thermal preference was assessed under both conditions with or without an immersion challenge, in order to detect the onset of the behavioural fever response. Our results defined the onset of the dsRNA induced behavioural fever at 18-20 days post fertilization (dpf). Significant differences were observed in dsRNA challenged larvae, which prefer higher temperatures (1-4 °C increase) throughout the experimental period as compared to non-challenged larvae. In parallel we measured the abundance of antiviral transcripts; viperin, gig2, irf7, trim25 and Mxb mRNAs in dsRNA challenged larvae under both thermal regimes: T R and T Ch . Significant increases in the abundance of all measured transcripts were recorded under thermal choice conditions signifying that thermo-coupling and the resultant enhancement of the immune response to dsRNA challenge occurs from 18 dpf onwards in the zebrafish. The results are of importance as they identify a key developmental stage where the neuro-immune interface matures in the zebrafish likely providing increased resistance to viral infection. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Real-Time Monitoring and Analysis of Zebrafish Electrocardiogram with Anomaly Detection.

    PubMed

    Lenning, Michael; Fortunato, Joseph; Le, Tai; Clark, Isaac; Sherpa, Ang; Yi, Soyeon; Hofsteen, Peter; Thamilarasu, Geethapriya; Yang, Jingchun; Xu, Xiaolei; Han, Huy-Dung; Hsiai, Tzung K; Cao, Hung

    2017-12-28

    Heart disease is the leading cause of mortality in the U.S. with approximately 610,000 people dying every year. Effective therapies for many cardiac diseases are lacking, largely due to an incomplete understanding of their genetic basis and underlying molecular mechanisms. Zebrafish ( Danio rerio ) are an excellent model system for studying heart disease as they enable a forward genetic approach to tackle this unmet medical need. In recent years, our team has been employing electrocardiogram (ECG) as an efficient tool to study the zebrafish heart along with conventional approaches, such as immunohistochemistry, DNA and protein analyses. We have overcome various challenges in the small size and aquatic environment of zebrafish in order to obtain ECG signals with favorable signal-to-noise ratio (SNR), and high spatial and temporal resolution. In this paper, we highlight our recent efforts in zebrafish ECG acquisition with a cost-effective simplified microelectrode array (MEA) membrane providing multi-channel recording, a novel multi-chamber apparatus for simultaneous screening, and a LabVIEW program to facilitate recording and processing. We also demonstrate the use of machine learning-based programs to recognize specific ECG patterns, yielding promising results with our current limited amount of zebrafish data. Our solutions hold promise to carry out numerous studies of heart diseases, drug screening, stem cell-based therapy validation, and regenerative medicine.

  2. Limb regeneration is impaired in an adult zebrafish model of diabetes mellitus.

    PubMed

    Olsen, Ansgar S; Sarras, Michael P; Intine, Robert V

    2010-01-01

    The zebrafish (Danio rerio) is an established model organism for the study of developmental processes, human disease, and tissue regeneration. We report that limb regeneration is severely impaired in our newly developed adult zebrafish model of type I diabetes mellitus. Intraperitoneal streptozocin injection of adult, wild-type zebrafish results in a sustained hyperglycemic state as determined by elevated fasting blood glucose values and increased glycation of serum protein. Serum insulin levels are also decreased and pancreas immunohistochemisty revealed a decreased amount of insulin signal in hyperglycemic fish. Additionally, the diabetic complications of retinal thinning and glomerular basement membrane thickening (early signs of retinopathy and nephropathy) resulting from the hyperglycemic state were evident in streptozocin-injected fish at 3 weeks. Most significantly, limb regeneration, following caudal fin amputation, is severely impaired in diabetic zebrafish and nonspecific toxic effects outside the pancreas were not found to contribute to impaired limb regeneration. This experimental system using adult zebrafish facilitates a broad spectrum of genetic and molecular approaches to study regeneration in the diabetic background. © 2010 by the Wound Healing Society.

  3. Real-Time Monitoring and Analysis of Zebrafish Electrocardiogram with Anomaly Detection

    PubMed Central

    Lenning, Michael; Fortunato, Joseph; Le, Tai; Clark, Isaac; Sherpa, Ang; Yi, Soyeon; Hofsteen, Peter; Thamilarasu, Geethapriya; Yang, Jingchun; Xu, Xiaolei; Hsiai, Tzung K.; Cao, Hung

    2017-01-01

    Heart disease is the leading cause of mortality in the U.S. with approximately 610,000 people dying every year. Effective therapies for many cardiac diseases are lacking, largely due to an incomplete understanding of their genetic basis and underlying molecular mechanisms. Zebrafish (Danio rerio) are an excellent model system for studying heart disease as they enable a forward genetic approach to tackle this unmet medical need. In recent years, our team has been employing electrocardiogram (ECG) as an efficient tool to study the zebrafish heart along with conventional approaches, such as immunohistochemistry, DNA and protein analyses. We have overcome various challenges in the small size and aquatic environment of zebrafish in order to obtain ECG signals with favorable signal-to-noise ratio (SNR), and high spatial and temporal resolution. In this paper, we highlight our recent efforts in zebrafish ECG acquisition with a cost-effective simplified microelectrode array (MEA) membrane providing multi-channel recording, a novel multi-chamber apparatus for simultaneous screening, and a LabVIEW program to facilitate recording and processing. We also demonstrate the use of machine learning-based programs to recognize specific ECG patterns, yielding promising results with our current limited amount of zebrafish data. Our solutions hold promise to carry out numerous studies of heart diseases, drug screening, stem cell-based therapy validation, and regenerative medicine. PMID:29283402

  4. Vitamin D in the avian egg. Its molecular identity and mechanism of incorporation into yolk.

    PubMed Central

    Fraser, D R; Emtage, J S

    1976-01-01

    The chemical identity of vitamin D in the egg of the domestic fowl was studied by analysing radioactivity in eggs from hens injected with [3H]cholecalciferol. Labelled molecules were found throughout the egg, but the concentration of total radioactivity in albumin was only 5-7% of that in yolk. In lipid extracts of yolk, more than 90% of the radioactivity was as unchanged cholecalciferol and 5% as 25-hydroxycholecalciferol. Only about 3% of the radioactivity in albumin was chloroform-soluble, and of this 40% was 25-hydroxycholecalciferol and 15% was cholecalciferol. Evidence is presented to support the idea that the specific transport of cholecalciferol into yolk is mediated by a cholecalciferol-binding protein in blood. This protein forms a complex with yolk proteins in transit from liver to ovary via the blood. A cholecalciferol-binding protein, chromatographically similar to that from blood, was found in egg yolk. It is postulated that cholecalciferol forms part of a complex with its specific binding protein, Ca2+ and the yolk phosphoprotein, phosvitin. This complex is then incorporated into yolk by the thecal cells of the ovarian follicle. PMID:189757

  5. Patterns of maternal yolk hormones in eastern screech owl eggs (Megascops asio)

    Hahn, D. Caldwell

    2011-01-01

    Owl clutches typically hatch asynchronously, and brood size hierarchies develop. In this study, we describe intra-clutch variation of testosterone, androstenedione, estradiol, and corticosterone in Eastern screech owl egg yolks. In order to assess whether these hormones may have originated in the follicle, we also characterize variation of testosterone, androstenedione, and corticosterone within the exterior, intermediate, and interior regions of the yolk. Concentrations of testosterone and androstenedione were distributed relatively evenly across egg lay order with the exception of first-laid eggs that had significantly lower concentrations of both androgens than eggs later in the laying sequence. Corticosterone and estradiol did not vary with laying order. Our results suggest that when food is abundant, yolk hormones are deposited in patterns that minimize sibling differences except to reduce dominance by the first-hatching chick. Testosterone and androstenedione concentrations varied throughout the yolk, while corticosterone was evenly distributed throughout the yolk. This supports a follicular origin for both yolk androgens, and an adrenal origin for yolk corticosterone.

  6. Vertical Transmission of a Drosophila Endosymbiont Via Cooption of the Yolk Transport and Internalization Machinery

    PubMed Central

    Herren, Jeremy K.; Paredes, Juan C.; Schüpfer, Fanny; Lemaitre, Bruno

    2013-01-01

    ABSTRACT Spiroplasma is a diverse bacterial clade that includes many vertically transmitted insect endosymbionts, including Spiroplasma poulsonii, a natural endosymbiont of Drosophila melanogaster. These bacteria persist in the hemolymph of their adult host and exhibit efficient vertical transmission from mother to offspring. In this study, we analyzed the mechanism that underlies their vertical transmission, and here we provide strong evidence that these bacteria use the yolk uptake machinery to colonize the germ line. We show that Spiroplasma reaches the oocyte by passing through the intercellular space surrounding the ovarian follicle cells and is then endocytosed into oocytes within yolk granules during the vitellogenic stages of oogenesis. Mutations that disrupt yolk uptake by oocytes inhibit vertical Spiroplasma transmission and lead to an accumulation of these bacteria outside the oocyte. Impairment of yolk secretion by the fat body results in Spiroplasma not reaching the oocyte and a severe reduction of vertical transmission. We propose a model in which Spiroplasma first interacts with yolk in the hemolymph to gain access to the oocyte and then uses the yolk receptor, Yolkless, to be endocytosed into the oocyte. Cooption of the yolk uptake machinery is a powerful strategy for endosymbionts to target the germ line and achieve vertical transmission. This mechanism may apply to other endosymbionts and provides a possible explanation for endosymbiont host specificity. PMID:23462112

  7. Improved quality of frozen boer goat semen with the addition of sweet orange essential oil on tris yolk and gentamicin extender

    NASA Astrophysics Data System (ADS)

    Sitepu, S. A.; Zaituni, U.; Jaswandi; Hendri

    2018-02-01

    This research aimed to determine the extent of frozen semen quality Boer Goat by essential oils of sweet orange peel in tris yolk and gentamicin extender. Research has been conducted at the Laboratory Loka Penelitian Kambing Potong Sei Putih, Deli Serdang, North Sumatra in February 2017. This study used a completely randomized design with 4 treatments and 5 replications. Treatments are 0.25; 0.5; 0.75 and 1% essential oils as additional diluent. The parameters were measured percentage Motility, membrane integrity, acrosome integrity and viability Boer Goat frozen semen. The results showed that the addition of essential oils as diluent semen was significant (P <0.01) in the percentage motility, Viability, membrane integrity and acrosome integrity Boer Goat frozen semen. Motility, membrane integrity, acrosome integrity and viability was significantly higher in all treated groups than the control group. The best results of all treatments In the study was the addition of essential oil as much as 1%.

  8. Does the oviparity-viviparity transition alter the partitioning of yolk in embryonic snakes?

    PubMed

    Wu, Yan-Qing; Qu, Yan-Fu; Wang, Xue-Ji; Gao, Jian-Fang; Ji, Xiang

    2017-11-29

    The oviparity-viviparity transition is a major evolutionary event, likely altering the reproductive process of the organisms involved. Residual yolk, a portion of yolk remaining unutilized at hatching or birth as parental investment in care, has been investigated in many oviparous amniotes but remained largely unknown in viviparous species. Here, we used data from 20 (12 oviparous and 8 viviparous) species of snakes to see if the oviparity-viviparity transition alters the partitioning of yolk in embryonic snakes. We used ANCOVA to test whether offspring size, mass and components at hatching or birth differed between the sexes in each species. We used both ordinary least squares and phylogenetic generalized least squares regressions to test whether relationships between selected pairs of offspring components were significant. We used phylogenetic ANOVA to test whether offspring components differed between oviparous and viviparous species and, more specifically, the hypothesis that viviparous snakes invest more in the yolk as parental investment in embryogenesis to produce more well developed offspring that are larger in linear size. In none of the 20 species was sex a significant source of variation in any offspring component examined. Newborn viviparous snakes on average contained proportionally more water and, after accounting for body dry mass, had larger carcasses but smaller residual yolks than did newly hatched oviparous snakes. The rates at which carcass dry mass (CDM) and fat body dry mass (FDM) increased with residual yolk dry mass (YDM) did not differ between newborn oviparous and viviparous snakes. Neither CDM nor FDM differed between newborn oviparous and viviparous snakes after accounting for YDM. Our results are not consistent with the hypothesis that the partitioning of yolk between embryonic and post-embryonic stages differs between snakes that differ in parity mode, but instead show that the partitioning of yolk in embryonic snakes is species

  9. The effect of pigeon yolk sac fluid on the growth behavior of calcium carbonate crystals.

    PubMed

    Song, Juan; Cheng, Haixia; Shen, Xinyu; Tong, Hua

    2015-03-01

    Previous experiments have proved that thermodynamically unstable calcium carbonate vaterite can exist for long periods in the yolk sac of a pigeon embryo. The aim of this article was to demonstrate the effect of in vitro mineralization of yolk sac fluid on calcium carbonate by direct precipitation. Experiments were conducted using pigeon yolk sac fluid and using lecithin extracted from pigeon yolk sac fluid as a control to investigate the regulating effects of the organic components in the embryo on the formation of the calcium carbonate precipitate. Multiple characterization methods were employed to study the various morphological patterns, sizes, crystal growth, and crystal phase transformations of the calcium carbonate precipitates as regulated by the yolk sac fluid extracted at different stages of incubation. The experimental results demonstrate that as the incubation proceeds towards the later stages, the composition and environmental features of the yolk sac fluid become more favorable for the formation of relatively unstable calcium carbonate phases with high energies of the vaterite state. The experiments conducted with extracted lecithin as the template for crystal growth yielded similar results. A large amount of organic molecules with polar functional groups carried by the yolk sac fluid have strong effects and can both initially induce the crystallization and regulate the aggregation of calcium carbonate. Furthermore, this regulation process is found to be closely related to the lecithin contained in yolk sac fluid. These observations confirm the changes in yolk sac fluid composition during incubation have significant effects on the production of vaterite, which implicates the calcium transport during embryo growth. © 2015 Poultry Science Association Inc.

  10. Rheological behaviour of egg white and egg yolk from different poultry specimen

    NASA Astrophysics Data System (ADS)

    Kumbár, V.; Nedomová, Š.; Votava, J.; Buchar, J.

    2017-01-01

    The main goal of this study is differences in rheological behaviour of hen (ISA BROWN), goose (Anser anser f. domestica) and Japanese quail (Coturnix japonica) egg white and egg yolk. The rheological behaviour of egg white and egg yolk was studied using a concentric cylinder viscometer. Rheological behaviour was pseudoplastic and flow curves were fitted by the Herschel-Bulkley model and Ostwald-de Waele model with high values of coeficients of determination R2. The meaning of rheological parameters on friction factors during flow of egg white and egg yolk in real tube has been shown. Preliminary information on time-dependent behaviour of tested liquids has been also obtained.

  11. Patterning mechanisms of the sub-intestinal venous plexus in zebrafish

    PubMed Central

    Goi, Michela; Childs, Sarah J.

    2017-01-01

    Despite considerable interest in angiogenesis, organ-specific angiogenesis remains less well characterized. The vessels that absorb nutrients from the yolk and later provide blood supply to the developing digestive system are primarily venous in origin. In zebrafish, these are the vessels of the Sub-intestinal venous plexus (SIVP) and they represent a new candidate model to gain an insight into the mechanisms of venous angiogenesis. Unlike other vessel beds in zebrafish, the SIVP is not stereotypically patterned and lacks obvious sources of patterning information. However, by examining the area of vessel coverage, number of compartments, proliferation and migration speed we have identified common developmental steps in SIVP formation. We applied our analysis of SIVP development to obd mutants that have a mutation in the guidance receptor PlexinD1. obd mutants show dysregulation of nearly all parameters of SIVP formation. We show that the SIVP responds to a unique combination of pathways that control both arterial and venous growth in other systems. Blocking Shh, Notch and Pdgf signaling has no effect on SIVP growth. However Vegf promotes sprouting of the predominantly venous plexus and Bmp promotes outgrowth of the structure. We propose that the SIVP is a unique model to understand novel mechanisms utilized in organ-specific angiogenesis. PMID:26477558

  12. C2orf71a/pcare1 is important for photoreceptor outer segment morphogenesis and visual function in zebrafish.

    PubMed

    Corral-Serrano, Julio C; Messchaert, Muriël; Dona, Margo; Peters, Theo A; Kamminga, Leonie M; van Wijk, Erwin; Collin, Rob W J

    2018-06-26

    Mutations in C2orf71 are causative for autosomal recessive retinitis pigmentosa and occasionally cone-rod dystrophy. We have recently discovered that the protein encoded by this gene is important for modulation of the ciliary membrane through the recruitment of an actin assembly module, and have therefore renamed the gene to PCARE (photoreceptor cilium actin regulator). Here, we report on the identification of two copies of the c2orf71/pcare gene in zebrafish, pcare1 and pcare2. To study the role of the gene most similar to human PCARE, pcare1, we have generated a stable pcare1 mutant zebrafish model (designated pcare1 rmc100/rmc100 ) in which the coding sequence was disrupted using CRISPR/Cas9 technology. Retinas of both embryonic (5 dpf) and adult (6 mpf) pcare1 rmc100/rmc100 zebrafish display a clear disorganization of photoreceptor outer segments, resembling the phenotype observed in Pcare -/- mice. Optokinetic response and visual motor response measurements indicated visual impairment in pcare1 rmc100/rmc100 zebrafish larvae at 5 dpf. In addition, electroretinogram measurements showed decreased b-wave amplitudes in pcare1 rmc100/rmc100 zebrafish as compared to age- and strain-matched wild-type larvae, indicating a defect in the transretinal current. Altogether, our data show that lack of pcare1 causes a retinal phenotype in zebrafish and indicate that the function of the PCARE gene is conserved across species.

  13. Maternal nodal and zebrafish embryogenesis.

    PubMed

    Bennett, James T; Stickney, Heather L; Choi, Wen-Yee; Ciruna, Brian; Talbot, William S; Schier, Alexander F

    2007-11-08

    In fish and amphibians, the dorsal axis is specified by the asymmetric localization of maternally provided components of the Wnt signalling pathway. Gore et al. suggest that the Nodal signal Squint (Sqt) is required as a maternally provided dorsal determinant in zebrafish. Here we test their proposal and show that the maternal activities of sqt and the related Nodal gene cyclops (cyc) are not required for dorsoventral patterning.

  14. Development of the inverted visceral yolk sac in three species of caviids (Rodentia, Caviomorpha, Caviidae).

    PubMed

    Miglino, M A; Franciolli, A L R; de Oliveira, M F; Ambrósio, C E; Bonatelli, M; Machado, M R F; Mess, A

    2008-08-01

    Guinea pig related rodents possess numerous derived placental characters. We attempt to identify diversity within the visceral yolk sac and its association with the chorioallantoic placenta in three species of caviids, two of them possessing a capsule formed by the decidua that covers the chorioallantoic placenta. The results verify that in early pregnancy all three species have an inverted yolk sac placenta. In advanced pregnancy the species differ: Galea spixii, as representative without a capsule, bear a yolk sac in apposition to the chorioallantoic placenta with signs of exchange activity until term. Galea is similar to other caviomorphs in this respect. In Dasyprocta leporina and Cuniculus paca, the representatives possessing a capsule, the yolk sac endoderm lacks signs of substance exchange. Evidently, the presence of a capsule prevents such an interaction. The variations established here must be considered if animal models for human placentation are required which have restricted access to the chorioallantoic placenta from the outside.

  15. Development and morphology of the inverted yolk sac in the guinea pig (Cavia porcellus).

    PubMed

    Vasconcelos, Bruno Gomes; Favaron, Phelipe Oliveira; Miglino, Maria Angelica; Mess, Andrea Maria

    2013-10-01

    Although the guinea pig is an important animal model for human placentation, aspects of fetal nutrition are not fully understood, especially in regard to the yolk sac that is regarded to be essential for early development of the embryo. We investigated differentiation by means of histology, histochemistry, immunohistochemistry, and transmission electron microscopy. Data suggest that the guinea pig's yolk sac was not sufficiently developed to facilitate substantial fetal nutrition in early pregnancy. On Day 12, it was a flat, inverted, but avascular structure. This was followed by differentiation to form the typical, highly villous and vascularized condition of advanced gestation. Finally, the yolk sac degenerated toward term. We suggest that the guinea pig and other caviomorphs rely predominantly on hemotrophic nutrition via the placenta even in very early pregnancy. In contrast to the general pattern of mammals, histiotrophic nutrition via yolk sac routes seems to be most essential during mid-gestation. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Development of the zebrafish mesonephros.

    PubMed

    Diep, Cuong Q; Peng, Zhenzhen; Ukah, Tobechukwu K; Kelly, Paul M; Daigle, Renee V; Davidson, Alan J

    2015-01-01

    The vertebrate kidney plays an essential role in removing metabolic waste and balancing water and salt. This is carried out by nephrons, which comprise a blood filter attached to an epithelial tubule with proximal and distal segments. In zebrafish, two nephrons are first formed as part of the embryonic kidney (pronephros) and hundreds are formed later to make up the adult kidney (mesonephros). Previous studies have focused on the development of the pronephros while considerably less is known about how the mesonephros is formed. Here, we characterize mesonephros development in zebrafish and examine the nephrons that form during larval metamorphosis. These nephrons, arising from proliferating progenitor cells that express the renal transcription factor genes wt1b, pax2a, and lhx1a, form on top of the pronephric tubules and develop a segmentation pattern similar to pronephric nephrons. We find that the pronephros acts as a scaffold for the mesonephros, where new nephrons fuse with the distal segments of the pronephric tubules to form the final branching network that characterizes the adult zebrafish kidney. © 2015 Wiley Periodicals, Inc.

  17. Development of the zebrafish mesonephros

    PubMed Central

    Diep, Cuong Q.; Peng, Zhenzhen; Ukah, Tobechukwu K.; Kelly, Paul M.; Daigle, Renee V.; Davidson, Alan J.

    2015-01-01

    The vertebrate kidney plays an essential role in removing metabolic waste and balancing water and salt. This is carried out by nephrons, which comprise a blood filter attached to an epithelial tubule with proximal and distal segments. In zebrafish, two nephrons are first formed as part of the embryonic kidney (pronephros) and hundreds are formed later to make up the adult kidney (mesonephros). Previous studies have focused on the development of the pronephros while considerably less is known about how the mesonephros is formed. Here, we characterize mesonephros development in zebrafish and examine the nephrons that form during larval metamorphosis. These nephrons, arising from proliferating progenitor cells that express the renal transcription factor genes wt1b, pax2a, and lhx1a, form on top of the pronephric tubules and develop a segmentation pattern similar to pronephric nephrons. We find that the pronephros acts as a scaffold for the mesonephros, where new nephrons fuse with the distal segments of the pronephric tubules to form the final branching network that characterizes the adult zebrafish kidney. PMID:25677367

  18. Zebrafish Discoveries in Cancer Epigenetics.

    PubMed

    Chernyavskaya, Yelena; Kent, Brandon; Sadler, Kirsten C

    2016-01-01

    The cancer epigenome is fundamentally different than that of normal cells. How these differences arise in and contribute to carcinogenesis is not known, and studies using model organisms such as zebrafish provide an opportunity to address these important questions. Modifications of histones and DNA comprise the complex epigenome, and these influence chromatin structure, genome stability and gene expression, all of which are fundamental to the cellular changes that cause cancer. The cancer genome atlas covers the wide spectrum of genetic changes associated with nearly every cancer type, however, this catalog is currently uni-dimensional. As the pattern of epigenetic marks and chromatin structure in cancer cells is described and overlaid on the mutational landscape, the map of the cancer genome becomes multi-dimensional and highly complex. Two major questions remain in the field: (1) how the epigenome becomes repatterned in cancer and (2) which of these changes are cancer-causing. Zebrafish provide a tractable in vivo system to monitor the epigenome during transformation and to identify epigenetic drivers of cancer. In this chapter, we review principles of cancer epigenetics and discuss recent work using zebrafish whereby epigenetic modifiers were established as cancer driver genes, thus providing novel insights into the mechanisms of epigenetic reprogramming in cancer.

  19. Time dependent effect of chronic embryonic exposure to ethanol on zebrafish: Morphology, biochemical and anxiety alterations.

    PubMed

    Ramlan, Nurul Farhana; Sata, Nurul Syafida Asma Mohd; Hassan, Siti Norhidayah; Bakar, Noraini Abu; Ahmad, Syahida; Zulkifli, Syaizwan Zahmir; Abdullah, Che Azurahanim Che; Ibrahim, Wan Norhamidah Wan

    2017-08-14

    Exposure to ethanol during critical period of development can cause severe impairments in the central nervous system (CNS). This study was conducted to assess the neurotoxic effects of chronic embryonic exposure to ethanol in the zebrafish, taking into consideration the time dependent effect. Two types of exposure regimen were applied in this study. Withdrawal exposure group received daily exposure starting from gastrulation until hatching, while continuous exposure group received daily exposure from gastrulation until behavioural assessment at 6dpf (days post fertilization). Chronic embryonic exposure to ethanol decreased spontaneous tail coiling at 24hpf (hour post fertilization), heart rate at 48hpf and increased mortality rate at 72hpf. The number of apoptotic cells in the embryos treated with ethanol was significantly increased as compared to the control. We also measured the morphological abnormalities and the most prominent effects can be observed in the treated embryos exposed to 1.50% and 2.00%. The treated embryos showed shorter body length, larger egg yolk, smaller eye diameter and heart edema as compared to the control. Larvae received 0.75% continuous ethanol exposure exhibited decreased swimming activity and increased anxiety related behavior, while withdrawal ethanol exposure showed increased swimming activity and decreased anxiety related behavior as compared to the respective control. Biochemical analysis exhibited that ethanol exposure for both exposure regimens altered proteins, lipids, carbohydrates and nucleic acids of the zebrafish larvae. Our results indicated that time dependent effect of ethanol exposure during development could target the biochemical processes thus leading to induction of apoptosis and neurobehavioral deficits in the zebrafish larvae. Thus it raised our concern about the safe limit of alcohol consumption for pregnant mother especially during critical periods of vulnerability for developing nervous system. Copyright © 2017

  20. Treatment with Myf5-morpholino results in somite patterning and brain formation defects in zebrafish.

    PubMed

    Chen, Yau-Hung; Tsai, Huai-Jen

    2002-10-01

    Myf-5 is a stage-dependent transcription factor associated with somitogenesis. To study its biological functions in zebrafish, we injected the Myf5-morpholinos ZMF-MO (antisense nucleotides 28 to 52) and ZMF-OTHER (antisense nucleotides 3 to 27) into zebrafish embryos to establish a myf-5 gene knockdown. No phenotypic abnormalities were observed following injection with 0.2 ng of ZMF-MO, but defects were displayed in 2 of 118 (1.7%) surviving embryos injected with 1 ng ZMF-MO. Morphological defects became more severe with increased dosages: 105 of 270 (38.9%) surviving embryos injected with 4.5 ng of ZMF-MO displayed such abnormalities as the absence of eyes or brains in addition to the following low-dosage defects in 24 hpf embryos: longitudinal yolk sacs, incomplete epiboly coverage, abnormal and suspended tail buds, diffused somite boundaries, and head shrinkage. Similar results were observed in the 4.5 ng ZMF-OTHER injection group. However, when fish were co-injected with 4.5 ng ZMF-MO and 4.5 ng myf-5 mRNA, abnormality rates decreased from 49.6% to 5.5%. Our results show that the brain krox20 gene was down-regulated at rhombomere 3; the pax2.1 gene was completely down-regulated; myoD was expressed normally; myogenin was substantially down-regulated in whole somites; and desmin was partly inhibited in newly forming somites. Our conclusion is that zebrafish Myf-5 may play important roles in brain formation and in the convergence and extension of shield epiblasts and tail buds during early embryogenesis, in addition to its well-understood role as a muscle regulatory factor in somites.

  1. Computer-aided meiotic maturation assay (CAMMA) of zebrafish (danio rerio) oocytes in vitro.

    PubMed

    Lessman, Charles A; Nathani, Ravikanth; Uddin, Rafique; Walker, Jamie; Liu, Jianxiong

    2007-01-01

    We have developed a new technique called Computer-Aided Meiotic Maturation Assay (CAMMA) for imaging large arrays of zebrafish oocytes and automatically collecting image files at regular intervals during meiotic maturation. This novel method uses a transparency scanner interfaced to a computer with macro programming that automatically scans and archives the image files. Images are stacked and analyzed with ImageJ to quantify changes in optical density characteristic of zebrafish oocyte maturation. Major advantages of CAMMA include (1) ability to image very large arrays of oocytes and follow individual cells over time, (2) simultaneously image many treatment groups, (3) digitized images may be stacked, animated, and analyzed in programs such as ImageJ, NIH-Image, or ScionImage, and (4) CAMMA system is inexpensive, costing less than most microscopes used in traditional assays. We have used CAMMA to determine the dose response and time course of oocyte maturation induced by 17alpha-hydroxyprogesterone (HP). Maximal decrease in optical density occurs around 5 hr after 0.1 micro g/ml HP (28.5 degrees C), approximately 3 hr after germinal vesicle migration (GVM) and dissolution (GVD). In addition to changes in optical density, GVD is accompanied by streaming of ooplasm to the animal pole to form a blastodisc. These dynamic changes are readily visualized by animating image stacks from CAMMA; thus, CAMMA provides a valuable source of time-lapse movies for those studying zebrafish oocyte maturation. The oocyte clearing documented by CAMMA is correlated to changes in size distribution of major yolk proteins upon SDS-PAGE, and, this in turn, is related to increased cyclin B(1) protein.

  2. Geographical trends in the yolk carotenoid composition of the pied flycatcher (Ficedula hypoleuca).

    PubMed

    Eeva, Tapio; Ruuskanen, Suvi; Salminen, Juha-Pekka; Belskii, Eugen; Järvinen, Antero; Kerimov, Anvar; Korpimäki, Erkki; Krams, Indrikis; Moreno, Juan; Morosinotto, Chiara; Mänd, Raivo; Orell, Markku; Qvarnström, Anna; Siitari, Heli; Slater, Fred M; Tilgar, Vallo; Visser, Marcel E; Winkel, Wolfgang; Zang, Herwig; Laaksonen, Toni

    2011-02-01

    Carotenoids in the egg yolks of birds are considered to be important antioxidants and immune stimulants during the rapid growth of embryos. Yolk carotenoid composition is strongly affected by the carotenoid composition of the female's diet at the time of egg formation. Spatial and temporal differences in carotenoid availability may thus be reflected in yolk concentrations. To assess whether yolk carotenoid concentrations or carotenoid profiles show any large-scale geographical trends or differences among habitats, we collected yolk samples from 16 European populations of the pied flycatcher, Ficedula hypoleuca. We found that the concentrations and proportions of lutein and some other xanthophylls in the egg yolks decreased from Central Europe northwards. The most southern population (which is also the one found at the highest altitude) also showed relatively low carotenoid levels. Concentrations of β-carotene and zeaxanthin did not show any obvious geographical gradients. Egg yolks also contained proportionally more lutein and other xanthophylls in deciduous than in mixed or coniferous habitats. We suggest that latitudinal gradients in lutein and xanthophylls reflect the lower availability of lutein-rich food items in the northern F. hypoleuca populations and in montane southern populations, which start egg-laying earlier relative to tree phenology than the Central European populations. Similarly, among-habitat variation is likely to reflect the better availability of lutein-rich food in deciduous forests. Our study is the first to indicate that the concentration and profile of yolk carotenoids may show large-scale spatial variation among populations in different parts of the species' geographical range. Further studies are needed to test the fitness effects of this geographical variation.

  3. Vascularization and VEGF expression altered in bovine yolk sacs from IVF and NT technologies.

    PubMed

    Mess, Andrea Maria; Carreira, Ana Claudia Oliveira; Marinovic de Oliveira, Cláudia; Fratini, Paula; Favaron, Phelipe Oliveira; Barreto, Rodrigo da Silva Nunes; Pfarrer, Christiane; Meirelles, Flávio Vieira; Miglino, Maria Angelica

    2017-01-01

    Reproductive technologies are widely used in cattle, although many are associated with high-embryonic mortality, especially during early gestation, when the yolk sac undergoes macroscopic changes in structure. We hypothesized that vasculogenesis and angiogenesis are affected, thereby affecting embryonic and placental differentiation. To test this, we studied yolk sac development and gene expression of the vascular endothelial growth factor system (VEGF-A, VEGFR-1/Flt-1, VEGFR-2/KDR). Samples from Days 25 to 40/41 of pregnancy from control cattle (n = 8) and from pregnancies established with IVF, (n = 7) or somatic cell nuclear transfer/clones (n = 5) were examined by histology, immunohistochemistry, and quantitative reverse transcriptase PCR. Yolk sacs in IVF- and nuclear transfer-derived pregnancies were immature. Development of villi was sparse in IVF yolk sacs, whereas vascularization was barely formed in clones and was associated, in part, with thin or interrupted endothelium. Transcript levels of the genes characterized exceed minimum detection limits for all groups, except in the mentioned clone with interrupted endothelium. Levels of mRNA for VEGF-A and VEGFR-2 were significantly higher in IVF yolk sacs. Clones had substantial individual variation in gene expression (both upregulation and downregulation). Our data confirmed the broad range in expression of VEGF genes. Furthermore, overexpression in IVF yolk sacs may compensate for an immature yolk sac structure, whereas in clones, patchy expression may cause structural alterations of blood vessels. In conclusion, we inferred that disturbances of yolk sac vasculature contributed to increased early embryonic mortality of bovine pregnancies established with reproductive technologies. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Facile, general and template-free construction of monodisperse yolk-shell metal@carbon nanospheres.

    PubMed

    Xu, Fei; Lu, Yuheng; Ma, Junhao; Huang, Zhike; Su, Quanfei; Fu, Ruowen; Wu, Dingcai

    2017-11-07

    Herein, we report a general and template-free protocol to construct novel yolk-shell metal@carbon nanospheres based on confined interfacial copolymerization, which greatly simplifies the synthetic route, yields uniform nanospheres with controllable diameters, and results in highly porous carbon shells. The yolk-shell Au@carbon shows improved adsorption capacity and high catalytic ability due to the synergistic effect of Au and the porous carbon shell.

  5. Transvection Arising from Transgene Interactions in Zebrafish.

    PubMed

    Keefe, Matthew D; Bonkowsky, Joshua L

    2017-02-01

    There has been a rapid expansion in use of transgenic technologies in zebrafish. We report a novel example of transinteractions of genetic elements, or transvection. This interaction led to a novel expression pattern and illustrates a precautionary example regarding use of transgenes in zebrafish.

  6. Effect of hesperidin dietary supplementation on hen performance, egg quality and yolk oxidative stability.

    PubMed

    Goliomytis, M; Orfanou, H; Petrou, E; Charismiadou, M A; Simitzis, P E; Deligeorgis, S G

    2014-02-01

    1. The purpose of this study was to evaluate the effects of dietary supplementation with hesperidin (one or 3 g/kg of feed) for 31 d on the performance, egg quality and yolk oxidative stability of brown and white laying hens (26-wk old). 2. Supplementation with hesperidin did not affect egg production, egg weight and egg quality traits. 3. No hesperidin effect on yolk and plasma cholesterol was observed. A strain effect was found with lower total and per g yolk cholesterol of brown hens in comparison to the white ones. 4. Oxidative stability of egg yolk, expressed as ng MDA/g yolk, was significantly improved in the hesperidin groups even from the first week of supplementation. At the same time, a significant improvement in the oxidative stability of egg yolk due to the incorporation of hesperidin in hens' diet was observed after 30 and 90 d of storage at 20°C and 4°C, respectively. 5. No hesperidin by strain interaction was detected for any of the traits measured. 6. In conclusion, incorporation of hesperidin to laying hens' feed did not affect productive and egg qualitative traits. On the other hand, dietary hesperidin supplementation significantly improved oxidative stability of both fresh and stored eggs. Antioxidant properties of hesperidin seem to make it a promising natural agent for improving the shelf life of eggs.

  7. Detection of egg yolk antibodies reflecting Salmonella enteritidis infections using a surface plasmon resonance biosensor.

    PubMed

    Thomas, Ekelijn; Bouma, Annemarie; van Eerden, Ellen; Landman, Wil J M; van Knapen, Frans; Stegeman, Arjan; Bergwerff, Aldert A

    2006-08-31

    A surface plasmon resonance (SPR) biosensor assay was developed on the basis of a lipopolysaccharide antigen of Salmonella enterica serovar enteritidis (S. enterica serovar enteritidis) to detect egg yolk antibodies against S. enterica serovar enteritidis. This biosensor assay was compared to two commercial ELISA kits based on LPS antigen and flagellar antigen. A number of 163 egg yolk and combined egg white and yolk samples from chickens experimentally infected with S. enterica serovar enteritidis and 90 egg yolk and combined egg white and yolk samples from uninfected chickens were analyzed. Receiver operating characteristic analysis of the data calculated a diagnostic sensitivity of 82% and a diagnostic specificity of 100%. The within-day coefficient of variation of a positive internal-control egg yolk was 1%. The SPR biosensor assay was able to detect antibodies in a significantly higher percentage of known positive samples than the commercial ELISA's. The anticipated use of the SPR biosensor assay is to determine the S. enterica serovar enteritidis serostatus of non-vaccinated layer hens.

  8. High Yolk Testosterone Transfer Is Associated with an Increased Female Metabolic Rate.

    PubMed

    Tschirren, Barbara; Ziegler, Ann-Kathrin; Canale, Cindy I; Okuliarová, Monika; Zeman, Michal; Giraudeau, Mathieu

    2016-01-01

    Yolk androgens of maternal origin are important mediators of prenatal maternal effects. Although in many species short-term benefits of exposure to high yolk androgen concentrations for the offspring have been observed, females differ substantially in the amount of androgens they transfer to their eggs. It suggests that costs for the offspring or the mother constrain the evolution of maternal hormone transfer. However, to date, the nature of these costs remains poorly understood. Unlike most previous work that focused on potential costs for the offspring, we here investigated whether high yolk testosterone transfer is associated with metabolic costs (i.e., a higher metabolic rate) for the mother. We show that Japanese quail (Coturnix japonica) females that deposit higher testosterone concentrations into their eggs have a higher resting metabolic rate. Because a higher metabolic rate is often associated with a shorter life span, this relationship may explain the negative association between yolk testosterone transfer and female longevity observed in the wild. Our results suggest that metabolic costs for the mother can balance the short-term benefits of yolk testosterone exposure for the offspring, thereby contributing to the maintenance of variation in maternal yolk hormone transfer in natural populations.

  9. Application of Zebrafish Model to Environmental Toxicology.

    PubMed

    Komoike, Yuta; Matsuoka, Masato

    2016-01-01

    Recently, a tropical freshwater fish, the zebrafish, has been generally used as a useful model organism in various fields of life science worldwide. The zebrafish model has also been applied to environmental toxicology; however, in Japan, it has not yet become widely used. In this review, we will introduce the biological and historical backgrounds of zebrafish as an animal model and their breeding. We then present the current status of toxicological experiments using zebrafish that were treated with some important environmental contaminants, including cadmium, organic mercury, 2,3,7,8-tetrachlorodibenzo-p-dioxin, and tributyltin. Finally, the future possible application of genetically modified zebrafish to the study of environmental toxicology is discussed.

  10. Zebrafish as a model for apolipoprotein biology: comprehensive expression analysis and a role for ApoA-IV in regulating food intake.

    PubMed

    Otis, Jessica P; Zeituni, Erin M; Thierer, James H; Anderson, Jennifer L; Brown, Alexandria C; Boehm, Erica D; Cerchione, Derek M; Ceasrine, Alexis M; Avraham-Davidi, Inbal; Tempelhof, Hanoch; Yaniv, Karina; Farber, Steven A

    2015-03-01

    Improved understanding of lipoproteins, particles that transport lipids throughout the circulation, is vital to developing new treatments for the dyslipidemias associated with metabolic syndrome. Apolipoproteins are a key component of lipoproteins. Apolipoproteins are proteins that structure lipoproteins and regulate lipid metabolism through control of cellular lipid exchange. Constraints of cell culture and mouse models mean that there is a need for a complementary model that can replicate the complex in vivo milieu that regulates apolipoprotein and lipoprotein biology. Here, we further establish the utility of the genetically tractable and optically clear larval zebrafish as a model of apolipoprotein biology. Gene ancestry analyses were implemented to determine the closest human orthologs of the zebrafish apolipoprotein A-I (apoA-I), apoB, apoE and apoA-IV genes and therefore ensure that they have been correctly named. Their expression patterns throughout development were also analyzed, by whole-mount mRNA in situ hybridization (ISH). The ISH results emphasized the importance of apolipoproteins in transporting yolk and dietary lipids: mRNA expression of all apolipoproteins was observed in the yolk syncytial layer, and intestinal and liver expression was observed from 4-6 days post-fertilization (dpf). Furthermore, real-time PCR confirmed that transcription of three of the four zebrafish apoA-IV genes was increased 4 hours after the onset of a 1-hour high-fat feed. Therefore, we tested the hypothesis that zebrafish ApoA-IV performs a conserved role to that in rat in the regulation of food intake by transiently overexpressing ApoA-IVb.1 in transgenic larvae and quantifying ingestion of co-fed fluorescently labeled fatty acid during a high-fat meal as an indicator of food intake. Indeed, ApoA-IVb.1 overexpression decreased food intake by approximately one-third. This study comprehensively describes the expression and function of eleven zebrafish apolipoproteins and

  11. Electrochemical immunosensor based on ensemble of nanoelectrodes for immunoglobulin IgY detection: application to identify hen's egg yolk in tempera paintings.

    PubMed

    Bottari, Fabio; Oliveri, Paolo; Ugo, Paolo

    2014-02-15

    A nanostructured electrochemical biosensor for detecting proteins of interest in work of art, in particular in tempera paintings, is presented. To determine egg yolk we focus here on the determination of immunoglobulin IgY. The transducers are nanoelectrode ensembles (NEEs), prepared via membrane templated electroless deposition of gold. Because of their geometrical and diffusion characteristics, NEEs are characterized by significantly low detection limits, moreover they display the capability of capturing proteins by interaction with the polycarbonate membrane of the NEE. At first, the proteic component of the paint is extracted by ultrasonication in an aqueous buffer, then IgY is captured by incubation on the NEE. The immunoglobulin is detected by treatment with anti-IgY labeled with horse radish peroxidase (Anti-IgY-HRP). The binding of the Anti-IgY-HRP is detected by recording the electrocatalytic signal caused by addition of H2O2 and methylene blue. The sensor detection capabilities are tested by analyzing both paint models, prepared in the lab, and real samples, from paintings of the XVIII-XX century. Multivariate exploratory analysis is applied to classify the voltammetric patterns, confirming the capability to differentiate egg-yolk tempera from other kind of tempera binders as well as from acrylic or oil paints. © 2013 Elsevier B.V. All rights reserved.

  12. Cardiac metastasis from yolk sac tumor: case report and review.

    PubMed

    Nunes, Maria Carmo Pereira; Moreira, Daniel Ribeiro; Ferrari, Teresa Cristina Abreu

    2013-01-01

    Cardiac metastasis of germ cell tumors is extremely rare, particularly in females. We report a case of a 26-year-old previously healthy woman who presented with a 5-month history of abdominal pain, weight loss, fever, generalized lymphadenopathy, and acanthosis nigricans. Biopsy of cervical lymph nodes revealed a poorly differentiated neoplasm. Immunohistochemical staining was positive for alpha-fetoprotein suggesting the diagnosis of a germ cell tumor. During the investigation, the patient developed heart failure and a mass attached to the right ventricle was detected by the echocardiogram. In a few days, she developed multiple organ failure and died. Post-mortem examination revealed a malignant mixed germ cell tumor of the right ovary with extensive hematogenic and lymphatic dissemination, a polypoid mass attached to the right ventricle, emboli in the endocardial and epicardial vessels, and infiltration surrounding the coronary arteries. To the best of our knowledge this is the third report of grossly visible heart metastases from a yolk sac tumor in a female patient. A summary of all published cases of germ cell tumors with cardiac metastasis over the last 20 years is also presented.

  13. Toxicity evaluation of β-diketone antibiotics on the development of embryo-larval zebrafish (Danio rerio).

    PubMed

    Wang, Huili; Che, Baoguang; Duan, Ailian; Mao, Jingwen; Dahlgren, Randy A; Zhang, Minghua; Zhang, Hongqin; Zeng, Aibing; Wang, Xuedong

    2014-10-01

    This study evaluated the effects of β-diketone antibiotics (DKAs) on the development of embryo-larval zebrafish (Danio rerio). When exposure to DKAs, developmental malformations, such as hatching delay, curved body axis, pericardial edema, uninflated swim bladder and yolk sac edema, were observed at 120 h postfertilization (hpf). The estimated 120 hpf nominal concentrations of no observed effect concentration and lowest observed effect concentration for DKAs were 18.75 and 37.50 mg/L, respectively, suggesting that DKAs have much lower toxicity than other persistent pollutants. Following DKA exposure, embryonic heart rates were significantly reduced as compared to the controls at 48 and 60 hpf. The peak bending motion frequency appeared 1 h earlier than in control embryos. The 2.34 and 9.38-mg/L treatment groups had a higher basal swim rate than control groups at 120 hpf in both light and light-to-dark photoperiod experiments. The occurrence of high speed swim rates was enhanced approximately threefold to sevenfold in the 2.34 and 9.38 mg/L treatments compared to the control. Glutathione (GSH) concentrations in the 2.34 and 9.38-mg/L treatments were significantly higher than the control at 72 hpf, suggesting that GSH production was induced at the end of the hatching period. When exposed to DKAs, zebrafish superoxide dismutase enzyme (SOD) activities were significantly inhibited in the early embryonic period, demonstrating that the clearing ability in zebrafish was lower than the generation rate of free radicals. In summary, the combined DKAs were developmentally toxic to zebrafish in their early life stages and had the ability to impair individual behaviors that are of great importance in the assessment of their ecological fitness. Copyright © 2013 Wiley Periodicals, Inc., a Wiley company.

  14. Offspring sex in a TSD gecko correlates with an interaction between incubation temperature and yolk steroid hormones.

    PubMed

    Ding, Guo-Hua; Yang, Jing; Wang, Jin; Ji, Xiang

    2012-12-01

    We incubated eggs of the Japanese gecko Gekko japonicus at three temperatures, and measured yolk testosterone (T) and 17β-estradiol (E2) levels at three time points in embryonic development (oviposition, 1/3 of incubation, and 2/3 of incubation), to examine whether maternal influence on offspring sex via yolk steroid hormone deposition is significant in the species. Eggs incubated at 24 °C and 32 °C produced mostly females, and eggs incubated at 28 °C almost a 50:50 sex ratio of hatchlings. Female-producing eggs were larger than male-producing eggs. Clutches in which eggs were incubated at the same temperature produced mostly same-sex siblings. Yolk T level at laying was negatively related to eggs mass, and yolk E2/T ratio was positively related to egg mass. Results of two-way ANOVA with incubation temperature and stage as the factors show that: yolk E2 level was higher at 32 °C than at 24 °C; yolk T level was higher, whereas yolk E2/T ratio was smaller, at 28 °C than at 24 °C; yolk E2 and T levels were higher at 2/3 than at 1/3 of incubation. Our data in G. japonucus show that: (1) maternal influence on offspring sex via yolk steroid hormone deposition is significant; (2) incubation temperature affects the dynamics of developmental changes in yolk steroid hormones; (3) influences of yolk steroid hormones on offspring sex are secondary relative to incubation temperature effects; and (4) offspring sex correlates with an interaction between incubation temperature and yolk steroid hormones.

  15. Offspring sex in a TSD gecko correlates with an interaction between incubation temperature and yolk steroid hormones

    NASA Astrophysics Data System (ADS)

    Ding, Guo-Hua; Yang, Jing; Wang, Jin; Ji, Xiang

    2012-12-01

    We incubated eggs of the Japanese gecko Gekko japonicus at three temperatures, and measured yolk testosterone (T) and 17β-estradiol (E2) levels at three time points in embryonic development (oviposition, 1/3 of incubation, and 2/3 of incubation), to examine whether maternal influence on offspring sex via yolk steroid hormone deposition is significant in the species. Eggs incubated at 24 °C and 32 °C produced mostly females, and eggs incubated at 28 °C almost a 50:50 sex ratio of hatchlings. Female-producing eggs were larger than male-producing eggs. Clutches in which eggs were incubated at the same temperature produced mostly same-sex siblings. Yolk T level at laying was negatively related to eggs mass, and yolk E2/T ratio was positively related to egg mass. Results of two-way ANOVA with incubation temperature and stage as the factors show that: yolk E2 level was higher at 32 °C than at 24 °C; yolk T level was higher, whereas yolk E2/T ratio was smaller, at 28 °C than at 24 °C; yolk E2 and T levels were higher at 2/3 than at 1/3 of incubation. Our data in G. japonucus show that: (1) maternal influence on offspring sex via yolk steroid hormone deposition is significant; (2) incubation temperature affects the dynamics of developmental changes in yolk steroid hormones; (3) influences of yolk steroid hormones on offspring sex are secondary relative to incubation temperature effects; and (4) offspring sex correlates with an interaction between incubation temperature and yolk steroid hormones.

  16. Zebrafish Model Systems for Developmental Neurobehavioral Toxicology

    PubMed Central

    Bailey, Jordan; Oliveri, Anthony; Levin, Edward D.

    2014-01-01

    Zebrafish offer many advantages that complement classic mammalian models for the study of normal development as well as for the teratogenic effects of exposure to hazardous compounds. The clear chorion and embryo of the zebrafish allow for continuous visualization of the anatomical changes associated with development, which, along with short maturation times and the capability of complex behavior, makes this model particularly useful for measuring changes to the developing nervous system. Moreover, the rich array of developmental, behavioral, and molecular benefits offered by the zebrafish have contributed to an increasing demand for the use of zebrafish in behavioral teratology. Essential for this endeavor has been the development of a battery of tests to evaluate a spectrum of behavior in zebrafish. Measures of sensorimotor plasticity, emotional function, cognition and social interaction have been used to characterize the persisting adverse effects of developmental exposure to a variety of chemicals including therapeutic drugs, drugs of abuse and environmental toxicants. In this review, we present and discuss such tests and data from a range of developmental neurobehavioral toxicology studies using zebrafish as a model. Zebrafish provide a key intermediate model between high throughput in vitro screens and the classic mammalian models as they have the accessibility of in vitro models and the complex functional capabilities of mammalian models. PMID:23723169

  17. The importance of Zebrafish in biomedical research.

    PubMed

    Tavares, Bárbara; Santos Lopes, Susana

    2013-01-01

    Zebrafish (Danio rerio) is an ideal model organism for the study of vertebrate development. This is due to the large clutches that each couple produces, with up to 200 embryos every 7 days, and to the fact that the embryos and larvae are small, transparent and undergo rapid external development. Using scientific literature research tools available online and the keywords Zebrafish, biomedical research, human disease, and drug screening, we reviewed original studies and reviews indexed in PubMed. In this review we summarized work conducted with this model for the advancement of our knowledge related to several human diseases. We also focused on the biomedical research being performed in Portugal with the zebrafish model. Powerful live imaging and genetic tools are currently available for zebrafish making it a valuable model in biomedical research. The combination of these properties with the optimization of automated systems for drug screening has transformed the zebrafish into "a top model" in biomedical research, drug discovery and toxicity testing. Furthermore, with the optimization of xenografts technology it will be possible to use zebrafish to aide in the choice of the best therapy for each patient. Zebrafish is an excellent model organism in biomedical research, drug development and in clinical therapy.

  18. Zebrafish model systems for developmental neurobehavioral toxicology.

    PubMed

    Bailey, Jordan; Oliveri, Anthony; Levin, Edward D

    2013-03-01

    Zebrafish offer many advantages that complement classic mammalian models for the study of normal development as well as for the teratogenic effects of exposure to hazardous compounds. The clear chorion and embryo of the zebrafish allow for continuous visualization of the anatomical changes associated with development, which, along with short maturation times and the capability of complex behavior, makes this model particularly useful for measuring changes to the developing nervous system. Moreover, the rich array of developmental, behavioral, and molecular benefits offered by the zebrafish have contributed to an increasing demand for the use of zebrafish in behavioral teratology. Essential for this endeavor has been the development of a battery of tests to evaluate a spectrum of behavior in zebrafish. Measures of sensorimotor plasticity, emotional function, cognition and social interaction have been used to characterize the persisting adverse effects of developmental exposure to a variety of chemicals including therapeutic drugs, drugs of abuse and environmental toxicants. In this review, we present and discuss such tests and data from a range of developmental neurobehavioral toxicology studies using zebrafish as a model. Zebrafish provide a key intermediate model between high throughput in vitro screens and the classic mammalian models as they have the accessibility of in vitro models and the complex functional capabilities of mammalian models. Copyright © 2013 Wiley Periodicals, Inc.

  19. Determination of yolk contamination in liquid egg white using Raman spectroscopy.

    PubMed

    Cluff, K; Konda Naganathan, G; Jonnalagada, D; Mortensen, I; Wehling, R; Subbiah, J

    2016-07-01

    Purified egg white is an important ingredient in a number of baked and confectionary foods because of its foaming properties. However, yolk contamination in amounts as low as 0.01% can impede the foaming ability of egg white. In this study, we used Raman spectroscopy to evaluate the hypothesis that yolk contamination in egg white could be detected based on its molecular optical properties. Yolk contaminated egg white samples (n = 115) with contamination levels ranging from 0% to 0.25% (on weight basis) were prepared. The samples were excited with a 785 nm laser and Raman spectra from 250 to 3,200 cm(-1) were recorded. The Raman spectra were baseline corrected using an optimized piecewise cubic interpolation on each spectrum and then normalized with a standard normal variate transformation. Samples were randomly divided into calibration (n = 77) and validation (n = 38) data sets. A partial least squares regression (PLSR) model was developed to predict yolk contamination levels, based on the Raman spectral fingerprint. Raman spectral peaks, in the spectral region of 1,080 and 1,666 cm(-1), had the largest influence on detecting yolk contamination in egg white. The PLSR model was able to correctly predict yolk contamination levels with an R(2) = 0.90 in the validation data set. These results demonstrate the capability of Raman spectroscopy for detection of yolk contamination at very low levels in egg white and present a strong case for development of an on-line system to be deployed in egg processing plants. © 2016 Poultry Science Association Inc.

  20. Inter-species variation in yolk steroid levels and a cowbird-host comparison

    Hahn, D. Caldwell; Hatfield, Jeffrey S.; Abdelnabi, Mahmoud A.; Wu, Julie M.; Igl, Lawrence D.; Ottinger, Mary A.

    2005-01-01

    We examined variability in yolk hormone levels among songbird species and the role of yolk steroids as a mechanism for enhanced exploitation of hosts by the parasitic Brown-headed Cowbird Molothrus ater. Within-clutch variation in yolk steroids has been found in several avian species in single species studies, but few comparisons have been made among species. We found a large range of differences in yolk testosterone among the seven passerine species examined, with significant differences between those at the high end (Song Sparrow Melospiza melodia , Red-winged Blackbird Agelaius phoeniceus, and House Sparrow, Passer domesticus ) and those at the low end (Eastern Phoebe Sayornis phoebe, and House Finch Carpodacus mexicanus ). We also found that the testosterone level in cowbird eggs was intermediate in relation to host species levels and was significantly lower than that in three common cowbird hosts (Song Sparrow, Red-winged Blackbird, and House Sparrow), but not significantly different from three others. Geographical comparisons of yolk testosterone levels in all cowbird subspecies and populations from several regions showed no significant differences, though a trend that deserves further exploration was the pattern of lowest level in the ancestral population of cowbirds in the central prairies and of highest level in the northwestern population where range invasion occurred approximately 40 years ago. The levels of 17 betaestradiol were similar in the seven songbird species examined, which is consistent with current hypotheses that this hormone plays a role in embryonic sexual differentiation. Further investigation is needed to determine whether the large differences observed among species in absolute level of yolk testosterone are the relevant focal point or whether target tissue sensitivity differences mediate the effects of this yolk steroid, particularly between parasitic and non-parasitic species.

  1. Rhesus monkey sperm cryopreservation with TEST-yolk extender in the absence of permeable cryoprotectant.

    PubMed

    Dong, Qiaoxiang; Correa, Liane M; VandeVoort, Catherine A

    2009-02-01

    Recently, there has been increased interest in ultra-rapid freezing with mammalian spermatozoa, especially for vitrification in the absence of cryoprotectants. Sperm cryopreservation in non-human primates has been successful, but the use of frozen-thawed sperm in standard artificial insemination (AI) remains difficult, and removal of permeable cryoprotectant may offer opportunities for increased AI success. The present study intended to explore the possibility of freezing rhesus monkey sperm in the absence of permeable cryoprotectants. Specifically, we evaluated various factors such as presence or absence of egg yolk, the percentage of egg yolk in the extenders, and the effect of cooling and thawing rate on the success of freezing without permeable cryoprotectants. Findings revealed that freezing with TEST in the absence of egg yolk offers little protection (<15% post-thaw motility). Egg yolk of 40% or more in TEST resulted in decreased motility, while egg yolk in the range of 20-30% yielded the most motile sperm. Cooling at a slow rate (29 degrees C/min) reduced post-thaw motility significantly for samples frozen with TEST-yolk alone, but had no effect for controls in the presence of glycerol. Similarly, slow thawing in room temperature air is detrimental for freezing without permeable cryoprotectant (<2% motility). In addition to motility, the ability of sperm to capacitate based on an increase in intracellular calcium levels upon activation with cAMP and caffeine suggested no difference between fresh and frozen-thawed motile sperm, regardless of treatment. In summary, the present study demonstrates that ejaculated and epididymal sperm from rhesus monkeys can be cryopreserved with TEST-yolk (20%) in the absence of permeable cryoprotectant when samples were loaded in a standard 0.25-mL straw, cooled rapidly in liquid nitrogen vapor at 220 degrees C/min, and thawed rapidly in a 37 degrees C water bath. This study also represents the first success of freezing

  2. Detailed lipid analysis of yolk platelets of amphibian (Bufo arenarum) oocytes.

    PubMed

    Buschiazzo, Jorgelina; Bruzzone, Ariana; Alonso, Telma Susana

    2003-06-01

    Yolk platelets, the principal components of amphibian oocytes, have been generally considered as material reservoirs. Their biochemical composition and function during oogenesis and early development have not been fully elucidated. The aim of this study was to carry out a lipidic characterization of yolk platelets from full-grown Bufo arenarum oocytes. Ovarian oocytes were manually obtained and the subcellular fraction was isolated by centrifugation at low velocity. Lipids were separated by thin-layer chromatography. For compositional analysis, they were derived by methanolysis, being identified and quantified in a gas-liquid chromatograph. Phospholipid content indicates that phosphatidylcholine and phosphatidylethanolamine are the main phospholipids followed by phosphatidylinositol, sphingomyelin, phosphatidylserine, and phosphatidic acid. Phospholipidic profile is similar to that in whole oocytes except for the absence of diphosphatidylglycerol in yolk platelets. Oleic, palmitic, and linoleic acids are the main fatty acids in phosphatidylcholine, and oleic acid is the principal one in phosphatidylethanolamine. In phosphatidic acid, palmitic, estearic, palmitoleic, and oleic acids represent 68 mol% of the total acyl groups. Phosphatidylinositol, enriched in arachidonic acid, is the most unsaturated phospholipid while sphingomyelin shows the lowest unsaturation index. The acyl group distribution in triacylglycerols is similar when yolk platelets and whole oocytes are compared. Polar and neutral lipids of yolk platelets determine the lipidic profile of the whole oocyte. The presence of unusual fatty acids as 14:0, 15:0, 15:1, 17:0, and 17:1 in phospholipids and triacylglycerols may indicate an oxidation mechanism different from beta-oxidation in yolk platelets and/or a structural and functional relation with mitochondria. Given that yolk platelets in amphibian oocytes may act in a dynamic fashion in development, their role should be reconsidered.

  3. 2017 Midwest Zebrafish Meeting Report.

    PubMed

    Sandquist, Elizabeth; Petersen, Sarah C; Smith, Cody J

    2017-12-01

    The 2017 Midwest Zebrafish meeting was held from June 16 to 18 at the University of Cincinnati, sponsored by the Cincinnati Children's Hospital Divisions of Developmental Biology, Molecular Cardiovascular Biology, and Gastroenterology, Hepatology, and Nutrition. The meeting, organized by Saulius Sumanas, Joshua Waxman, and Chunyue Yin, hosted >130 attendees from 16 different states. Scientific sessions were focused on morphogenesis, neural development, novel technologies, and disease models, with Steve Ekker, Stephen Potter, and Lila Solnica-Krezel presenting keynote talks. In this article, we highlight the results and emerging themes from the meeting.

  4. Nuclear movement regulated by non-Smad Nodal signaling via JNK is associated with Smad signaling during zebrafish endoderm specification.

    PubMed

    Hozumi, Shunya; Aoki, Shun; Kikuchi, Yutaka

    2017-11-01

    Asymmetric nuclear positioning is observed during animal development, but its regulation and significance in cell differentiation remain poorly understood. Using zebrafish blastulae, we provide evidence that nuclear movement towards the yolk syncytial layer, which comprises extraembryonic tissue, occurs in the first cells fated to differentiate into the endoderm. Nodal signaling is essential for nuclear movement, whereas nuclear envelope proteins are involved in movement through microtubule formation. Positioning of the microtubule-organizing center, which is proposed to be crucial for nuclear movement, is regulated by Nodal signaling and nuclear envelope proteins. The non-Smad JNK signaling pathway, which is downstream of Nodal signaling, regulates nuclear movement independently of the Smad pathway, and this nuclear movement is associated with Smad signal transduction toward the nucleus. Our study provides insight into the function of nuclear movement in Smad signaling toward the nucleus, and could be applied to the control of TGFβ signaling. © 2017. Published by The Company of Biologists Ltd.

  5. Yolk testosterone and corticosterone in hierarchical follicles and laid eggs of Japanese quail exposed to long-term restraint stress.

    PubMed

    Okuliarová, Monika; Sárniková, Bozena; Rettenbacher, Sophie; Skrobánek, Peter; Zeman, Michal

    2010-01-01

    Environmental and behavioural stimuli experienced by egg-laying female birds contribute to intra- and inter-female differences in hormones in the egg yolk with consequences for offspring development. The understanding of physiological mechanisms underlying yolk hormone deposition can aid progress in this field. In our study, we measured the concentration of testosterone and corticosterone in hierarchical follicles and egg yolks of Japanese quail in control and chronic stress conditions. Experimental females were reared under hypodynamia, a model situation for restraint stress, from day 3 to 63 days of age. For yolk hormone analysis, four largest follicles of ovarian hierarchy (F1-F4), eggs present in the oviduct and eggs laid on the day before were collected. In chronically stressed birds, yolk testosterone concentrations decreased from F2 onwards, while yolk corticosterone content was increased from the beginning to the end of egg formation. The follicular profile of hormones suggested testosterone transfer into the yolk directly from granulosa and theca cells, with the highest accumulation during a period 48-72 h before laying the egg. Yolk corticosterone was accumulated from maternal plasma preferentially in early stages of follicular development under control conditions and also in last stages of egg formation under stress conditions. These specific patterns of hormone deposition indicate periods when stimuli experienced by female can substantially modify hormonal content of eggs. Lower testosterone and increased corticosterone yolk concentrations in stressed quail may represent signals mediating information about adverse environmental conditions from the mother to progeny.

  6. Protective effect of egg yolk peptide on bone metabolism.

    PubMed

    Kim, Hye Kyung; Lee, Sena; Leem, Kang-Hyun

    2011-03-01

    Osteoporosis is a major health problem worldwide, and most current therapy used in osteoporosis treatment acts by either increasing bone formation or decreasing bone resorption. However, the adverse effects of these therapies may preclude their long-term use. We examined the effects of egg yolk water-soluble peptide (YPEP) on bone metabolism as an alternative to current therapeutic agents in ovariectomized (OVX) rats. In the first step, the in vitro effects of YPEP on bone loss were determined. The proliferation, collagen content, and alkaline phosphatase activity of preosteoblastic MC3T3-E1 cells and osteoclastogenesis from bone marrow-derived precursor cells were measured. The in vivo experiment confirmed the positive effect of YPEP on bone tissue. Three-month-old female Sprague-Dawley rats were either sham operated or ovariectomized and fed commercial chow diet or 0.1% YPEP-supplemented diet for 3 month. YPEP increased preosteoblastic MC3T3-E1 cell proliferation and alkaline phosphatase activity in a dose-dependent manner. Collagen content was also increased by YPEP treatment. Furthermore, YPEP potently suppressed osteoclastogenesis from bone marrow-derived precursor cells. YPEP (100 μg/mL) abolished the formation of osteoclasts positive for tartrate-resistant acid phosphatase. OVX rats supplemented with YPEP showed an osteoprotective effect, as the bone mineral density and cortical thickness in the tibia were increased compared with the OVX controls. Moreover, histological data indicate that YPEP prevented the cancellous bone loss induced by ovariectomy. None of these protective effects were observed in casein-treated rats. The present study suggests that YPEP is a promising alternative to current therapeutic agents for the management of osteoporosis.

  7. Sprouting Buds of Zebrafish Research in Malaysia: First Malaysia Zebrafish Disease Model Workshop.

    PubMed

    Okuda, Kazuhide Shaun; Tan, Pei Jean; Patel, Vyomesh

    2016-04-01

    Zebrafish is gaining prominence as an important vertebrate model for investigating various human diseases. Zebrafish provides unique advantages such as optical clarity of embryos, high fecundity rate, and low cost of maintenance, making it a perfect complement to the murine model equivalent in biomedical research. Due to these advantages, researchers in Malaysia are starting to take notice and incorporate the zebrafish model into their research activities. However, zebrafish research in Malaysia is still in its infancy stage and many researchers still remain unaware of the full potential of the zebrafish model or have limited access to related tools and techniques that are widely utilized in many zebrafish laboratories worldwide. To overcome this, we organized the First Malaysia Zebrafish Disease Model Workshop in Malaysia that took place on 11th and 12th of November 2015. In this workshop, we showcased how the zebrafish model is being utilized in the biomedical field in international settings as well as in Malaysia. For this, notable international speakers and those from local universities known to be carrying out impactful research using zebrafish were invited to share some of the cutting edge techniques that are used in their laboratories that may one day be incorporated in the Malaysian scientific community.

  8. Automated measurement of zebrafish larval movement

    PubMed Central

    Cario, Clinton L; Farrell, Thomas C; Milanese, Chiara; Burton, Edward A

    2011-01-01

    Abstract The zebrafish is a powerful vertebrate model that is readily amenable to genetic, pharmacological and environmental manipulations to elucidate the molecular and cellular basis of movement and behaviour. We report software enabling automated analysis of zebrafish movement from video recordings captured with cameras ranging from a basic camcorder to more specialized equipment. The software, which is provided as open-source MATLAB functions, can be freely modified and distributed, and is compatible with multiwell plates under a wide range of experimental conditions. Automated measurement of zebrafish movement using this technique will be useful for multiple applications in neuroscience, pharmacology and neuropsychiatry. PMID:21646414

  9. Zebrafish tracking using convolutional neural networks.

    PubMed

    Xu, Zhiping; Cheng, Xi En

    2017-02-17

    Keeping identity for a long term after occlusion is still an open problem in the video tracking of zebrafish-like model animals, and accurate animal trajectories are the foundation of behaviour analysis. We utilize the highly accurate object recognition capability of a convolutional neural network (CNN) to distinguish fish of the same congener, even though these animals are indistinguishable to the human eye. We used data augmentation and an iterative CNN training method to optimize the accuracy for our classification task, achieving surprisingly accurate trajectories of zebrafish of different size and age zebrafish groups over different time spans. This work will make further behaviour analysis more reliable.

  10. Automated measurement of zebrafish larval movement.

    PubMed

    Cario, Clinton L; Farrell, Thomas C; Milanese, Chiara; Burton, Edward A

    2011-08-01

    The zebrafish is a powerful vertebrate model that is readily amenable to genetic, pharmacological and environmental manipulations to elucidate the molecular and cellular basis of movement and behaviour. We report software enabling automated analysis of zebrafish movement from video recordings captured with cameras ranging from a basic camcorder to more specialized equipment. The software, which is provided as open-source MATLAB functions, can be freely modified and distributed, and is compatible with multiwell plates under a wide range of experimental conditions. Automated measurement of zebrafish movement using this technique will be useful for multiple applications in neuroscience, pharmacology and neuropsychiatry.

  11. Zebrafish tracking using convolutional neural networks

    NASA Astrophysics Data System (ADS)

    Xu, Zhiping; Cheng, Xi En

    2017-02-01

    Keeping identity for a long term after occlusion is still an open problem in the video tracking of zebrafish-like model animals, and accurate animal trajectories are the foundation of behaviour analysis. We utilize the highly accurate object recognition capability of a convolutional neural network (CNN) to distinguish fish of the same congener, even though these animals are indistinguishable to the human eye. We used data augmentation and an iterative CNN training method to optimize the accuracy for our classification task, achieving surprisingly accurate trajectories of zebrafish of different size and age zebrafish groups over different time spans. This work will make further behaviour analysis more reliable.

  12. Learning and memory in zebrafish larvae

    PubMed Central

    Roberts, Adam C.; Bill, Brent R.; Glanzman, David L.

    2013-01-01

    Larval zebrafish possess several experimental advantages for investigating the molecular and neural bases of learning and memory. Despite this, neuroscientists have only recently begun to use these animals to study memory. However, in a relatively short period of time a number of forms of learning have been described in zebrafish larvae, and significant progress has been made toward their understanding. Here we provide a comprehensive review of this progress; we also describe several promising new experimental technologies currently being used in larval zebrafish that are likely to contribute major insights into the processes that underlie learning and memory. PMID:23935566

  13. Systematic approaches to toxicology in the zebrafish.

    PubMed

    Peterson, Randall T; Macrae, Calum A

    2012-01-01

    As the current paradigms of drug discovery evolve, it has become clear that a more comprehensive understanding of the interactions between small molecules and organismal biology will be vital. The zebrafish is emerging as a complement to existing in vitro technologies and established preclinical in vivo models that can be scaled for high-throughput. In this review, we highlight the current status of zebrafish toxicology studies, identify potential future niches for the model in the drug development pipeline, and define the hurdles that must be overcome as zebrafish technologies are refined for systematic toxicology.

  14. A review of monoaminergic neuropsychopharmacology in zebrafish.

    PubMed

    Maximino, Caio; Herculano, Anderson Manoel

    2010-12-01

    Monoamine neurotransmitters are the major regulatory mechanisms in the vertebrate brain, involved in the adjustment of motivation, emotion, and cognition. The chemical anatomy of these systems is thought to be highly conserved in the brain of all vertebrates, including zebrafish. Recently, the development of behavioral assays in zebrafish allowed the neuropsychopharmacological investigation of these circuits and its functions. Here we review neuroanatomical, genetic, neurochemical, and psychopharmacological evidence regarding the roles of histaminergic, dopaminergic, noradrenergic, serotonergic, and melatonergic systems in this species. We conclude that, in spite of species differences, zebrafish are suitable for the investigation of neuropsychopharmacology of drugs that affect theses systems; nonetheless, more thorough validation of behavioral methods is still needed.

  15. Exposure to tris(1,3-dichloro-2-propyl) phosphate for Two generations decreases fecundity of zebrafish at environmentally relevant concentrations.

    PubMed

    Zhang, Yongkang; Li, Meng; Li, Shuying; Wang, Qiangwei; Zhu, Guonian; Su, Guanyong; Letcher, Robert J; Liu, Chunsheng

    2018-05-14

    Previous studies reported that exposure to environmentally relevant concentrations of TDCIPP significantly decreased the number of cumulative eggs in zebrafish, but effects on the quantity of eggs and sperms remained unknown. Therefore, in this study, effects of TDCIPP on yolk diameter, surface morphology of eggs, sperm density and total motility were evaluated. First generation (F0) zebrafish larvae (Danio rerio) were exposed to 0, 50, 500 or 5000 ng/L tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) from 14 days post fertilization (dpf) to 120 dpf. The F0 generation of zebrafish were paired and F1 generation of embryos were collected and continuously exposed to the same concentrations of TDCIPP until 150 dpf. TDCIPP bioconcentration in the whole body as well as effects on survival and fecundity were evaluated in F1 generation. Exposure to TDCIPP resulted in an accumulation of the chemical and decreased survival of F1 generation of zebrafish. TDCIPP decreased cumulative production and changed surface morphology of eggs in females. In males, TDCIPP decreased total motility of sperm but did not affect sperm density. These effects on quality of egg and sperm might be responsible for the decreased hatching rates observed in cross mating experiments. Furthermore, TDCIPP exposure resulted in down-regulated gene expression related to gonadal development and maturation of germ cells in females or/and males, and the down-regulation was correlated to decreased fecundity. Taken together, the results suggested that exposure to TDCIPP could decrease the quantity of eggs and sperms by down-regulating the expression of genes related to gonadal development and maturation of germ cells in zebrafish. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Effect of rainbow trout (Oncorhynchus mykiss) seminal plasma on the post-thaw quality of ram semen cryopreserved in a soybean lecithin-based or egg yolk-based extender.

    PubMed

    Ustuner, Burcu; Alcay, Selim; Toker, M Berk; Nur, Zekariya; Gokce, Elif; Sonat, Fusun Ak; Gul, Zulfiye; Duman, Muhammed; Ceniz, Cafer; Uslu, Aydın; Sagirkaya, Hakan; Soylu, M Kemal

    2016-01-01

    The aim of the current study was to evaluate the effects of different concentrations of rainbow trout seminal plasma (RTSP) (0.1%, 1% and 10%) in extenders containing either egg yolk or lecithin for use in Awassi ram semen cryopreservation. Pooled sperm were diluted in a two-step dilution method to a final concentration of 1/5 (semen/extender) in egg yolk or lecithin extender containing no RTSP, 0.1%, 1% or 10% RTSP (v/v). Semen samples were assessed for sperm motility, plasma membrane integrity [hypoosmotic swelling test (HOST) and Hoechst 33258] and defective acrosomes [FITC-conjugated Pisum sativum agglutinin (PSA-FITC)] at the following five time points: after dilution with extender A; after equilibration; and post-thaw at 0h, 3h and 5h. Malondialdehyde (MDA) was examined only after thawing. Freezing and thawing procedures (dilution, equilibration and post-thaw incubation at 0h, 3h and 5h) negatively affected the motility (P<0.001) and acrosome integrity (P<0.001). Additionally, freezing and thawing negatively affected the plasma membrane integrity, as determined by the HOST and Hoechst 33258 (P<0.001). The extender group affected the motility (P<0.001) and the HOST results (P<0.001). Levels of MDA in the egg yolk extender with 1% RTSP group were significantly lower than in the lecithin control group (P<0.05). In conclusion, the egg yolk extender groups that were supplemented with 10% and 1% RTSP provided greater cryoprotective effects for semen survivability during 5h incubation than the other extender groups. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. PhOTO Zebrafish: A Transgenic Resource for In Vivo Lineage Tracing during Development and Regeneration

    PubMed Central

    Dempsey, William P.; Fraser, Scott E.; Pantazis, Periklis

    2012-01-01

    Background Elucidating the complex cell dynamics (divisions, movement, morphological changes, etc.) underlying embryonic development and adult tissue regeneration requires an efficient means to track cells with high fidelity in space and time. To satisfy this criterion, we developed a transgenic zebrafish line, called PhOTO, that allows photoconvertible optical tracking of nuclear and membrane dynamics in vivo. Methodology PhOTO zebrafish ubiquitously express targeted blue fluorescent protein (FP) Cerulean and photoconvertible FP Dendra2 fusions, allowing for instantaneous, precise targeting and tracking of any number of cells using Dendra2 photoconversion while simultaneously monitoring global cell behavior and morphology. Expression persists through adulthood, making the PhOTO zebrafish an excellent tool for studying tissue regeneration: after tail fin amputation and photoconversion of a ∼100µm stripe along the cut area, marked differences seen in how cells contribute to the new tissue give detailed insight into the dynamic process of regeneration. Photoconverted cells that contributed to the regenerate were separated into three distinct populations corresponding to the extent of cell division 7 days after amputation, and a subset of cells that divided the least were organized into an evenly spaced, linear orientation along the length of the newly regenerating fin. Conclusions/Significance PhOTO zebrafish have wide applicability for lineage tracing at the systems-level in the early embryo as well as in the adult, making them ideal candidate tools for future research in development, traumatic injury and regeneration, cancer progression, and stem cell behavior. PMID:22431986

  18. The Ndst Gene Family in Zebrafish: Role of Ndst1b in Pharyngeal Arch Formation

    PubMed Central

    Haitina, Tatjana; Habicher, Judith; Ledin, Johan; Kjellén, Lena

    2015-01-01

    Heparan sulfate (HS) proteoglycans are ubiquitous components of the extracellular matrix and plasma membrane of metazoans. The sulfation pattern of the HS glycosaminoglycan chain is characteristic for each tissue and changes during development. The glucosaminyl N-deacetylase/N-sulfotransferase (NDST) enzymes catalyze N-deacetylation and N-sulfation during HS biosynthesis and have a key role in designing the sulfation pattern. We here report on the presence of five NDST genes in zebrafish. Zebrafish ndst1a, ndst1b, ndst2a and ndst2b represent duplicated mammalian orthologues of NDST1 and NDST2 that arose through teleost specific genome duplication. Interestingly, the single zebrafish orthologue ndst3, is equally similar to tetrapod Ndst3 and Ndst4. It is likely that a local duplication in the common ancestor of lobe-finned fish and tetrapods gave rise to these two genes. All zebrafish Ndst genes showed distinct but partially overlapping expression patterns during embryonic development. Morpholino knockdown of ndst1b resulted in delayed development, craniofacial cartilage abnormalities, shortened body and pectoral fin length, resembling some of the features of the Ndst1 mouse knockout. PMID:25767878

  19. Zebrafish models flex their muscles to shed light on muscular dystrophies.

    PubMed

    Berger, Joachim; Currie, Peter D

    2012-11-01

    Muscular dystrophies are a group of genetic disorders that specifically affect skeletal muscle and are characterized by progressive muscle degeneration and weakening. To develop therapies and treatments for these diseases, a better understanding of the molecular basis of muscular dystrophies is required. Thus, identification of causative genes mutated in specific disorders and the study of relevant animal models are imperative. Zebrafish genetic models of human muscle disorders often closely resemble disease pathogenesis, and the optical clarity of zebrafish embryos and larvae enables visualization of dynamic molecular processes in vivo. As an adjunct tool, morpholino studies provide insight into the molecular function of genes and allow rapid assessment of candidate genes for human muscular dystrophies. This unique set of attributes makes the zebrafish model system particularly valuable for the study of muscle diseases. This review discusses how recent research using zebrafish has shed light on the pathological basis of muscular dystrophies, with particular focus on the muscle cell membrane and the linkage between the myofibre cytoskeleton and the extracellular matrix.

  20. Cell adhesion in zebrafish myogenesis: distribution of intermediate filaments, microfilaments, intracellular adhesion structures and extracellular matrix.

    PubMed

    Costa, Manoel L; Escaleira, Roberta C; Jazenko, Fernanda; Mermelstein, Claudia S

    2008-10-01

    To overcome the limitations of in vitro studies, we have been studying myogenesis in situ in zebrafish embryos, at a sub-cellular level. While in previous works we focused on myofibrillogenesis and some aspects of adhesion structures, here we describe in more detail cell adhesion structures and interactions among cytoskeletal components, membrane and extracellular matrix during zebrafish muscle development. We studied the intermediate filaments, and we describe the full range of desmin distribution in zebrafish development, from perinuclear to striated, until its deposition around the intersomite septa of older somites. This adhesion structure, positive for desmin and actin, has not been previously observed in myogenesis in vitro. We also show that actin is initially located in the intersomite septum region whereas it is confined to the myofibrils later on. While actin localization changes during development, the adhesion complex proteins vinculin, paxillin, talin, dystrophin, laminin and fibronectin always appear exclusively at the intersomite septa, and appear to be co-distributed, even though the extracellular proteins accumulates before the intracellular ones. Contrary to the adhesion proteins, that are continuously distributed, desmin and sarcomeric actin form triangular aggregates among the septa and the cytoskeleton. We studied the cytoskeletal linker plectin as well, and we show that it has a distribution similar to desmin and not to actin. We conclude that the in situ adhesion structures differ from their in vitro counterparts, and that the actual zebrafish embryo myogenesis is quite different than that which occurs in in vitro systems. Copyright 2008 Wiley-Liss, Inc.

  1. Direct Effects of Microalgae and Protists on Herring (Clupea harengus) Yolk Sac Larvae

    PubMed Central

    Illing, Björn; Moyano, Marta; Niemax, Jan; Peck, Myron A.

    2015-01-01

    This study investigated effects of microalgae (Rhodomonas baltica) and heterotrophic protists (Oxyrrhis marina) on the daily growth, activity, condition and feeding success of Atlantic herring (Clupea harengus) larvae from hatch, through the end of the endogenous (yolk sac) period. Yolk sac larvae were reared in the presence and absence of microplankton and, each day, groups of larvae were provided access to copepods. Larvae reared with microalgae and protists exhibited precocious (2 days earlier) and ≥ 60% increased feeding incidence on copepods compared to larvae reared in only seawater (SW). In the absence and presence of microalgae and protists, life span and growth trajectories of yolk sac larvae were similar and digestive enzyme activity (trypsin) and nutritional condition (RNA-DNA ratio) markedly declined in all larvae directly after yolk sac depletion. Thus, microplankton promoted early feeding but was not sufficient to alter life span and growth during the yolk sac phase. Given the importance of early feeding, field programs should place greater emphasis on the protozooplankton-ichthyoplankton link to better understand match-mismatch dynamics and bottom-up drivers of year class success in marine fish. PMID:26035592

  2. Direct Effects of Microalgae and Protists on Herring (Clupea harengus) Yolk Sac Larvae.

    PubMed

    Illing, Björn; Moyano, Marta; Niemax, Jan; Peck, Myron A

    2015-01-01

    This study investigated effects of microalgae (Rhodomonas baltica) and heterotrophic protists (Oxyrrhis marina) on the daily growth, activity, condition and feeding success of Atlantic herring (Clupea harengus) larvae from hatch, through the end of the endogenous (yolk sac) period. Yolk sac larvae were reared in the presence and absence of microplankton and, each day, groups of larvae were provided access to copepods. Larvae reared with microalgae and protists exhibited precocious (2 days earlier) and ≥ 60% increased feeding incidence on copepods compared to larvae reared in only seawater (SW). In the absence and presence of microalgae and protists, life span and growth trajectories of yolk sac larvae were similar and digestive enzyme activity (trypsin) and nutritional condition (RNA-DNA ratio) markedly declined in all larvae directly after yolk sac depletion. Thus, microplankton promoted early feeding but was not sufficient to alter life span and growth during the yolk sac phase. Given the importance of early feeding, field programs should place greater emphasis on the protozooplankton-ichthyoplankton link to better understand match-mismatch dynamics and bottom-up drivers of year class success in marine fish.

  3. Effect of dietary karaya saponin on serum and egg yolk cholesterol in laying hens.

    PubMed

    Afrose, S; Hossain, M S; Tsujii, H

    2010-12-01

    1. The objective of the study was to investigate the effect of dietary karaya saponin on cholesterol deposition in laying hens. 2. A total of 40 Boris Brown hens were randomly assigned at 20 weeks of age to 4 treatment groups and fed on diets supplemented with 0 (control), 25, 50 or 75 mg/kg karaya saponin for an 8-week experimental period. 3. After 8 weeks of dietary supplementation, karaya-saponin-treated groups had significantly lower serum cholesterol (23·0%) and triglycerides but increased high density lipoproteins cholesterol concentration than controls, irrespective of karaya saponin content in the diet. Egg yolk cholesterol and triglycerides were also significantly reduced by dietary karaya saponin. Hepatic cholesterol and triglycerides were significantly reduced by karaya saponin but bile acids concentration in the faeces and liver were significantly increased by karaya saponin. The concentrations of oleic, linoleic and linolenic acids in the yolk were greater in hens receiving karaya saponin than in controls. Karaya saponin significantly increased egg production, feed efficiency and yolk colour compared with controls. Karaya saponin tended to increase egg weight, feed consumption, Haugh units, albumen weight and yolk index. 4. In conclusion, karaya saponin is a potential agent for reducing yolk cholesterol concentration together with an overall increase of production performance and improvement in egg quality.

  4. Effects of karaya saponin and Rhodobacter capsulatus on yolk cholesterol in laying hens.

    PubMed

    Afrose, S; Hossain, M S; Maki, T; Tsujii, H

    2010-06-01

    1. It has been reported that karaya saponin and Rhodobacter capsulatus individually have hypocholesterolaemic activity in laying hens. This study focuses on the effect of adding karaya saponin with R. capsulatus to hen's diet with regard to serum and egg yolk cholesterol and triglycerides. 2. A total of 56 Boris Brown laying hens were divided into 7 groups at 20 weeks of age. Combinations of 25, 50, 75 mg kg(-1) karaya saponin and R. capsulatus 200 and 400 mg kg(-1) were used as treatment groups. 3. After 8 weeks of supplementation, the effects of all the combinations of karaya saponin and R. capsulatus on serum and egg yolk cholesterol, triglycerides, and high-density lipoprotein (HDL)-cholesterol were greater than either karaya saponin or R. capsulatus alone. The combination of karaya saponin 50 mg kg(-1)+ R. capsulatus 400 mg kg(-1) exhibited the greatest reduction of serum (325%) and yolk (225%) cholesterol and the greatest increase of faecal, liver bile acids and yolk fatty acid (oleic, linoleic and linolenic) concentrations. In addition, egg production and yolk colour were significantly improved by the combined use of karaya saponin and R. capsulatus supplementation. 4. Therefore, the dietary supplementation of karaya saponin and R. capsulatus may lead to the production of a low-cholesterol egg, with production performance maintained at a standard level.

  5. Serum and egg yolk antibody detection in chickens infected with low pathogenicity avian influenza virus.

    PubMed

    Sá e Silva, Mariana; Swayne, David E

    2012-09-01

    Surveillance for low pathogenicity avian influenza virus (LPAIV) infections has primarily relied on labor-intensive collection and serological testing of serum, but for many poultry diseases, easier-to-collect yolk samples have replaced serum for surveillance testing. A time-course LPAIV infection study in layers was performed to evaluate the utility of antibody detection in serum vs. egg yolk samples. Layers inoculated with the LPAIV A/Bobwhite Quail/Pennsylvania/20304/98 (H7N2) were tested for antibody levels in the serum and egg yolk by using the agar gel immunodiffusion test (AGID), hemagglutination-inhibition test (HI), and a commercially available enzyme-linked immunosorbent assay (ELISA). Anti-influenza specific antibodies were detected in the serum as early as 7 days postinoculation (DPI), and the majority of the hens remained positive until 42 DPI. Antibodies in the egg yolk were first detected by AGID at 7 DPI, which was also the first day of detection in serum. However, the majority of the eggs were positive by all techniques at 11 DPI and remained positive until 42 DPI, at which time the number of AGID+ and HI+ samples declined slightly as compared to ELISA+ samples. These results suggest that egg yolk can be an alternative to serum for flock serological surveillance against LPAIV infections, and the three methods (AGID, HI, and ELISA) will give similar results for first 42 days after infection, although AGID may give earlier positive response.

  6. Improved fatty acid analysis of conjugated linoleic acid rich egg yolk triacylglycerols and phospholipid species.

    PubMed

    Shinn, Sara; Liyanage, Rohana; Lay, Jack; Proctor, Andrew

    2014-07-16

    Reports from chicken conjugated linoleic acid (CLA) feeding trials are limited to yolk total fatty acid composition, which consistently described increased saturated fatty acids and decreased monounsaturated fatty acids. However, information on CLA triacylglycerol (TAG) and phospholipid (PL) species is limited. This study determined the fatty acid composition of total lipids in CLA-rich egg yolk produced with CLA-rich soy oil, relative to control yolks using gas chromatography with flame ionization detection (GC-FID), determined TAG and PL fatty acid compositions by thin-layer chromatography-GC-FID (TLC-GC-FID), identified intact PL and TAG species by TLC-matrix-assisted laser desorption/ionization mass spectrometry (TLC-MALDI-MS), and determined the composition of TAG and PL species in CLA and control yolks by direct flow infusion electrospray ionization MS (DFI ESI-MS). In total, 2 lyso-phosphatidyl choline (LPC) species, 1 sphingomyelin species, 17 phosphatidyl choline species, 19 TAG species, and 9 phosphatidyl ethanolamine species were identified. Fifty percent of CLA was found in TAG, occurring predominantly in C52:5 and C52:4 TAG species. CLA-rich yolks contained significantly more LPC than did control eggs. Comprehensive lipid profiling may provide insight on relationships between lipid composition and the functional properties of CLA-rich eggs.

  7. A Novel Pattern of Yolk Processing in Developing Snake Eggs (Colubridae: Lampropeltini) and its Functional and Evolutionary Implications.

    PubMed

    Powers, Kathryn G; Blackburn, Daniel G

    2017-07-01

    Early amniotic vertebrates evolved large-yolked eggs that permitted production of well-developed, terrestrial hatchlings. This reproductive pattern required new mechanisms for cellularizing the yolk and mobilizing it for embryonic use. In birds, cells that line the yolk sac cavity phagocytose and digest the yolk material, a pattern that is commonly assumed to be universal among oviparous amniotes. However, recent evidence challenges the assumption that all squamate reptiles conform to the avian developmental pattern. In this paper, scanning electron microscopy and histology were used to study mechanisms of yolk processing in two colubrid snakes, the kingsnake Lampropeltis getula and the milksnake L. triangulum. Endodermal cells from the yolk sac splanchnopleure proliferate massively as they invade the yolk sac cavity, forming elaborate chains of interlinked cells. These cells grow in size as they phagocytose yolk material. Subsequently, vitelline capillaries invade the masses of yolk-laden cells and become coated with the endodermal cells, forming an elaborate meshwork of cell-coated strands. The close association of cells, yolk, and blood vessels allows yolk material to be cellularized, digested, and transported for embryonic use. The overall pattern is like that of the corn snake Pantherophis guttatus, but contrasts markedly with that of birds. Given recent evidence that this developmental pattern may also occur in certain lizards, we postulate that it is ancestral for squamates. Studies of lizards, crocodilians, and turtles are needed to clarify the evolutionary history of this pattern and its implications for the evolution of the amniotic (terrestrial) vertebrate egg. © 2017 Wiley Periodicals, Inc.

  8. Effects of probiotic administration on zebrafish development and reproduction.

    PubMed

    Carnevali, O; Avella, M A; Gioacchini, G

    2013-07-01

    As the consumption of probiotics increases worldwide, scientists focus on identifying bacterial strains able to improve human life quality and evidence the biological pathways affected by probiotic treatment. In this review, some recent observations on the effects of changes of microbiota on zebrafish metabolism were discussed. In addition, the effects of Lactobacillus rhamnosus - a component of the human gut microflora - as a diet supplement on Danio rerio were presented. When administered chronically, L. rhamnosus may affect larval development and the physiology of reproductive system in the zebrafish model. It was hypothesized exogenous L. rhamnosus accelerates larval growth and backbone development by acting on insulin-like growth factors-I (igfI) and -II (igfII), peroxisome proliferator activated receptors-α and -β, (pparα,β) vitamin D receptor-α (vdrα) and retinoic acid receptor-γ (rarγ). Gonadal differentiation was anticipated at 6weeks together with a higher expression of gnrh3 at the larval stage when L. rhamnosus was administered throughout development. Moreover, brood stock alimented with a L. rhamnosus-supplemented diet showed better reproductive performances as per follicles development, ovulated oocytes quantification and embryos quality. A plausible involvement of factors such as leptin, and kiss1 and 2 in the improvements was concluded. The observations made on the physiology of female reproduction were correlated with the gene expression of a gigantic number of factors as the aromatase cytochrome p 19 (cyp19a), the vitellogenin (vtg) and the α isoform of the E2 receptor (erα), luteinizing hormone receptor (lhr), 20-β hydroxysteroid dehydrogenase (20β-hsd), membrane progesterone receptors α and β, cyclin B, activinβA1, smad2, transforming growth factor β1 (tgfβ1), growth differentiation factor9 (gdf9) and bone morphogenetic protein15 (bmp15.) A model in which the exogenous L. rhamnosus in the digestive tract of zebrafish from the

  9. Zebrafish Models for Human Acute Organophosphorus Poisoning.

    PubMed

    Faria, Melissa; Garcia-Reyero, Natàlia; Padrós, Francesc; Babin, Patrick J; Sebastián, David; Cachot, Jérôme; Prats, Eva; Arick Ii, Mark; Rial, Eduardo; Knoll-Gellida, Anja; Mathieu, Guilaine; Le Bihanic, Florane; Escalon, B Lynn; Zorzano, Antonio; Soares, Amadeu M V M; Raldúa, Demetrio

    2015-10-22

    Terrorist use of organophosphorus-based nerve agents and toxic industrial chemicals against civilian populations constitutes a real threat, as demonstrated by the terrorist attacks in Japan in the 1990 s or, even more recently, in the Syrian civil war. Thus, development of more effective countermeasures against acute organophosphorus poisoning is urgently needed. Here, we have generated and validated zebrafish models for mild, moderate and severe acute organophosphorus poisoning by exposing zebrafish larvae to different concentrations of the prototypic organophosphorus compound chlorpyrifos-oxon. Our results show that zebrafish models mimic most of the pathophysiological mechanisms behind this toxidrome in humans, including acetylcholinesterase inhibition, N-methyl-D-aspartate receptor activation, and calcium dysregulation as well as inflammatory and immune responses. The suitability of the zebrafish larvae to in vivo high-throughput screenings of small molecule libraries makes these models a valuable tool for identifying new drugs for multifunctional drug therapy against acute organophosphorus poisoning.

  10. Episodic-like memory in zebrafish.

    PubMed

    Hamilton, Trevor J; Myggland, Allison; Duperreault, Erika; May, Zacnicte; Gallup, Joshua; Powell, Russell A; Schalomon, Melike; Digweed, Shannon M

    2016-11-01

    Episodic-like memory tests often aid in determining an animal's ability to recall the what, where, and which (context) of an event. To date, this type of memory has been demonstrated in humans, wild chacma baboons, corvids (Scrub jays), humming birds, mice, rats, Yucatan minipigs, and cuttlefish. The potential for this type of memory in zebrafish remains unexplored even though they are quickly becoming an essential model organism for the study of a variety of human cognitive and mental disorders. Here we explore the episodic-like capabilities of zebrafish (Danio rerio) in a previously established mammalian memory paradigm. We demonstrate that when zebrafish were presented with a familiar object in a familiar context but a novel location within that context, they spend more time in the novel quadrant. Thus, zebrafish display episodic-like memory as they remember what object they saw, where they saw it (quadrant location), and on which occasion (yellow or blue walls) it was presented.

  11. Matrix metalloproteinase-9 plays a role in protecting zebrafish from lethal infection with Listeria monocytogenes by enhancing macrophage migration.

    PubMed

    Shan, Ying; Zhang, Yikai; Zhuo, Xunhui; Li, Xiaoliang; Peng, Jinrong; Fang, Weihuan

    2016-07-01

    Zebrafish could serve as an alternative animal model for pathogenic bacteria in multiple infectious routes. Our previous study showed that immersion infection in zebrafish with Listeria monocytogenes did not cause lethality but induced transient expression of several immune response genes. We used an Affymetrix gene chip to examine the expression profiles of genes of zebrafish immersion-infected with L. monocytogenes. A total of 239 genes were up-regulated and 56 genes down-regulated compared with uninfected fish. Highest expression (>20-fold) was seen with the mmp-9 gene encoding the matrix metalloproteinase-9 (Mmp-9) known to degrade the extracellular matrix proteins. By morpholino knockdown of mmp-9, we found that the morphants showed rapid death with much higher bacterial load after intravenous or intraventricular (brain ventricle) infection with L. monocytogenes. Macrophages in mmp-9-knockdown morphants had significant defect in migrating to the brain cavity upon intraventricular infection. Decreased migration of murine macrophages with knockdown of mmp-9 and cd44 was also seen in transwell inserts with 8-μm pore polycarbonate membrane, as compared with the scrambled RNA. These findings suggest that Mmp-9 is a protective molecule against infection by L. monocytogenes by engaging in migration of zebrafish macrophages to the site of infection via a non-proteolytic role. Further work is required on the molecular mechanisms governing Mmp-9-driven macrophage migration in zebrafish. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Yolk proteins in the male reproductive system of the fruit fly Drosophila melanogaster: spatial and temporal patterns of expression.

    PubMed

    Majewska, Magdalena M; Suszczynska, Agnieszka; Kotwica-Rolinska, Joanna; Czerwik, Tomasz; Paterczyk, Bohdan; Polanska, Marta A; Bernatowicz, Piotr; Bebas, Piotr

    2014-04-01

    In insects, spermatozoa develop in the testes as clones of single spermatogonia covered by specialized somatic cyst cells (cc). Upon completion of spermatogenesis, spermatozoa are released to the vas deferens, while the cc remain in the testes and die. In the fruit fly Drosophila melanogaster, the released spermatozoa first reach the seminal vesicles (SV), the organ where post-testicular maturation begins. Here, we demonstrate the temporal (restricted to the evening and early night hours) accumulation of membranous vesicles containing proteins in the SV lumen of D. melanogaster. When SV vesicles were isolated from the semen and co-incubated with testis-derived spermatozoa in vitro, their contents bound to the spermatozoa along their tails. The proteins of the SV vesicles were then characterized using 2-D electrophoresis. We identified a prominent protein spot of around 45-47 kDa, which disappears from the SV vesicles in the night, i.e. shortly after they appear in the SV lumen. Sequencing of peptides derived from this spot by mass spectrometry revealed identity with three yolk proteins (YP1-3). This unexpected result was confirmed by western blotting, which demonstrated that SV vesicles contain proteins that are immunoreactive with an antibody against D. melanogaster YP1-3. The expression of all yp genes was shown to be a unique feature of testis tissues. Using RNA probes we found that their transcripts localize exclusively to the cc that cover fully developed spermatozoa in the distal part of each testis. Temporally, the expression of yp genes was found to be restricted to a short period during the day and is followed by the evening accumulation of YP proteins in the cc. Immunohistochemical staining confirmed that cc are the source of SV vesicles containing YPs that are released into the SV lumen. These vesicles interact with spermatozoa and as a result, YPs become extrinsic proteins of the sperm membrane. Thus, we describe for the first time the expression of

  13. Polygenic Sex Determination System in Zebrafish

    PubMed Central

    Liew, Woei Chang; Bartfai, Richard; Lim, Zijie; Sreenivasan, Rajini; Siegfried, Kellee R.; Orban, Laszlo

    2012-01-01

    Background Despite the popularity of zebrafish as a research model, its sex determination (SD) mechanism is still unknown. Most cytogenetic studies failed to find dimorphic sex chromosomes and no primary sex determining switch has been identified even though the assembly of zebrafish genome sequence is near to completion and a high resolution genetic map is available. Recent publications suggest that environmental factors within the natural range have minimal impact on sex ratios of zebrafish populations. The primary aim of this study is to find out more about how sex is determined in zebrafish. Methodology/Principal Findings Using classical breeding experiments, we found that sex ratios across families were wide ranging (4.8% to 97.3% males). On the other hand, repeated single pair crossings produced broods of very similar sex ratios, indicating that parental genotypes have a role in the sex ratio of the offspring. Variation among family sex ratios was reduced after selection for breeding pairs with predominantly male or female offspring, another indication that zebrafish sex is regulated genetically. Further examinations by a PCR-based “blind assay" and array comparative genomic hybridization both failed to find universal sex-linked differences between the male and female genomes. Together with the ability to increase the sex bias of lines by selective breeding, these data suggest that zebrafish is unlikely to utilize a chromosomal sex determination (CSD) system. Conclusions/Significance Taken together, our study suggests that zebrafish sex is genetically determined with limited, secondary influences from the environment. As we have not found any sign for CSD in the species, we propose that the zebrafish has a polygenic sex determination system. PMID:22506019

  14. What is the Thalamus in Zebrafish?

    PubMed Central

    Mueller, Thomas

    2012-01-01

    Current research on the thalamus and related structures in the zebrafish diencephalon identifies an increasing number of both neurological structures and ontogenetic processes as evolutionary conserved between teleosts and mammals. The patterning processes, for example, which during the embryonic development of zebrafish form the thalamus proper appear largely conserved. Yet also striking differences between zebrafish and other vertebrates have been observed, particularly when we look at mature and histologically differentiated brains. A case in point is the migrated preglomerular complex of zebrafish which evolved only within the lineage of ray-finned fish and has no counterpart in mammals or tetrapod vertebrates. Based on its function as a sensory relay station with projections to pallial zones, the preglomerular complex has been compared to specific thalamic nuclei in mammals. However, no thalamic projections to the zebrafish dorsal pallium, which corresponds topologically to the mammalian isocortex, have been identified. Merely one teleostean thalamic nucleus proper, the auditory nucleus, projects to a part of the dorsal telencephalon, the pallial amygdala. Studies on patterning mechanisms identify a rostral and caudal domain in the embryonic thalamus proper. In both, teleosts and mammals, the rostral domain gives rise to GABAergic neurons, whereas glutamatergic neurons originate in the caudal domain of the zebrafish thalamus. The distribution of GABAergic derivatives in the adult zebrafish brain, furthermore, revealed previously overlooked thalamic nuclei and redefined already established ones. These findings require some reconsideration regarding the topological origin of these adult structures. In what follows, I discuss how evolutionary conserved and newly acquired features of the developing and adult zebrafish thalamus can be compared to the mammalian situation. PMID:22586363

  15. [Chemotherapy of yolk sac tumor heterotransplanted to nude mice (author's transl)].

    PubMed

    Sawada, M; Hayakawa, K; Matsui, Y; Nishiura, H; Okudaira, Y

    1980-10-01

    Chemotherapy of yolk sac tumor heterotransplanted to nude mice was studied. 1. Yolk sac tumor of the ovary taken from a 38-year -old woman was transplanted to BALB/c female nude mice. The transplantable tumor cells produce a solid tumor, designated as YST-1 tumor. The YST-1 tumor cells preserve the histological appearance of a human yolk sac tumor and produce x-fetoprotein. The tumors on passage 8 were used for experimental chemotherapy. 2. Anticancer drugs clinically known to be effective for ovarian cancer, such as Adriamycin, Carbazilquinone, 5-Fluorouracil, Cyclophosphamide, Mitomycin C, Chromomycin A3, Vinblastine and Bleomycin were administered intraperitoneally to tumor-bearing nude mice. Tumor size was measured two or three times a week during the course of experiments. Therapeutic effects were evaluated by tumor size and relative tumor size before and after experiments. Among these drugs, Vinblastine and Bleomycin combination showed the significant effect arresting the growth of YST-1 tumor.

  16. A novel isolation method for hen egg yolk antibody, "IgY".

    PubMed

    Hatta, H; Kim, M; Yamamoto, T

    1990-10-01

    A method for isolation of egg yolk immunoglobulin, IgG, a livetin protein, was investigated. Several natural gums (carrageenan and xanthan gum) were found to be effective for removal of yolk lipoprotein as a precipitate. The effect was pronounced with lambda-carrageenan and the lipid content in the supernatant after removal of the resulting precipitate was less than 0.4% of that of egg yolk. IgY remained in this supernatant, with a yield of 86%, and was isolated by chromatography on a column of DEAE-Sephacel followed by salting-out with sodium sulfate. IgY thus isolated was almost pure (98%) and the yield was 70 to 100 mg per egg.

  17. Egg Yolk Factor of Staphylococcus aureus II. Characterization of the Lipase Activity

    PubMed Central

    Shah, D. B.; Wilson, J. B.

    1965-01-01

    Shah, D. B. (University of Wisconsin, Madison), and J. B. Wilson. Egg yolk factor of Staphylococcus aureus. II. Characterization of the lipase activity. J. Bacteriol. 89:949–953. 1965.—The staphylococcal egg yolk factor was characterized as a lipase. The enzyme had an optimal pH of 7.8, but the optimal pH of stability was 7. Substrate specificity data showed that the relative rate of hydrolysis was lowest with triacetin as substrate, was maximal with tributyrin, and decreased as the chain length of the acyl moieties increased. The enzyme showed an absolute requirement for a fatty acid acceptor like calcium, when the acyl moiety of triglyceride was water-insoluble. Magnesium, strontium, and barium functioned equally well as fatty acid acceptors. The enzyme was able to hydrolyze coconut oil, peanut oil, olive oil, and egg yolk oil. PMID:14276120

  18. Improving foaming properties of yolk-contaminated egg albumen by basic soy protein.

    PubMed

    Wang, Guang; Wang, Tong

    2009-10-01

    Yolk contamination of egg white is a common problem in the egg breaking industry. Foaming properties of egg white protein are affected by such contamination, but proteins of basic nature may restore the foaming properties of the yolk-contaminated egg white protein. The purpose of this study was to chemically modify a soy protein, that is, to esterify the acidic groups on the protein and to study the potential of such modified protein in improving foaming. We showed that the modification changed the isoelectric point of soy protein isolate (SPI) from 4.5 to about 10. Sonication was proven to be a very effective means to redisperse the methanol-denatured soy protein during reaction, as shown by the improved solubility profile. Such modified basic protein, that is, the sonicated-modified SPI (SMSPI), when added to the yolk-contaminated (at 0.4% level, as-is basis) egg white, gave significantly improved foaming properties. We have shown that the slight change in pH due to the addition of SMSPI was not the reason for improved foaming performance; instead, the modified protein itself was the main reason for such improvement. Addition of SMSPI increased the foaming performance of both pure egg white and yolk-contaminated egg white. SMSPI consistently performed better than the unmodified SPI for improving foaming. Addition of SMSPI (16%, based on dry egg white, and 1.6% based on liquid egg white) fully restored foam expansion and foam liquid stability of 0.4% yolk-contaminated egg white, and it even out-performed the foaming of pure white protein. Therefore, a feasible solution to restore the foaming properties of yolk-contaminated egg white has been identified. It is expected that such modified SPI can be used as an additive or ingredient in foaming formulation, especially when the egg white protein is suspected of lipid contamination.

  19. Antioxidant and ACE Inhibitory Bioactive Peptides Purified from Egg Yolk Proteins

    PubMed Central

    Yousr, Marwa; Howell, Nazlin

    2015-01-01

    Protein by-products from the extraction of lecithin from egg yolk can be converted into value-added products, such as bioactive hydrolysates and peptides that have potential health enhancing antioxidant, and antihypertensive properties. In this study, the antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of peptides isolated and purified from egg yolk protein were investigated. Defatted egg yolk was hydrolyzed using pepsin and pancreatin and sequentially fractionated by ultrafiltration, followed by gel filtration to produce egg yolk gel filtration fractions (EYGF). Of these, two fractions, EYGF-23 and EYGF-33, effectively inhibited the peroxides and thiobarbituric acid reactive substance (TBARS) in an oxidizing linoleic acid model system. The antioxidant mechanism involved superoxide anion and hydroxyl radicals scavenging and ferrous chelation. The presence of hydrophobic amino acids such as tyrosine (Y) and tryptophan (W), in sequences identified by LC-MS as WYGPD (EYGF-23) and KLSDW (EYGF-33), contributed to the antioxidant activity and were not significantly different from the synthetic BHA antioxidant. A third fraction (EYGF-56) was also purified from egg yolk protein by gel filtration and exhibited high ACE inhibitory activity (69%) and IC50 value (3.35 mg/mL). The SDNRNQGY peptide (10 mg/mL) had ACE inhibitory activity, which was not significantly different from that of the positive control captopril (0.5 mg/mL). In addition, YPSPV in (EYGF-33) (10 mg/mL) had higher ACE inhibitory activity compared with captopril. These findings indicated a substantial potential for producing valuable peptides with antioxidant and ACE inhibitory activity from egg yolk. PMID:26690134

  20. Antioxidant and ACE Inhibitory Bioactive Peptides Purified from Egg Yolk Proteins.

    PubMed

    Yousr, Marwa; Howell, Nazlin

    2015-12-07

    Protein by-products from the extraction of lecithin from egg yolk can be converted into value-added products, such as bioactive hydrolysates and peptides that have potential health enhancing antioxidant, and antihypertensive properties. In this study, the antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of peptides isolated and purified from egg yolk protein were investigated. Defatted egg yolk was hydrolyzed using pepsin and pancreatin and sequentially fractionated by ultrafiltration, followed by gel filtration to produce egg yolk gel filtration fractions (EYGF). Of these, two fractions, EYGF-23 and EYGF-33, effectively inhibited the peroxides and thiobarbituric acid reactive substance (TBARS) in an oxidizing linoleic acid model system. The antioxidant mechanism involved superoxide anion and hydroxyl radicals scavenging and ferrous chelation. The presence of hydrophobic amino acids such as tyrosine (Y) and tryptophan (W), in sequences identified by LC-MS as WYGPD (EYGF-23) and KLSDW (EYGF-33), contributed to the antioxidant activity and were not significantly different from the synthetic BHA antioxidant. A third fraction (EYGF-56) was also purified from egg yolk protein by gel filtration and exhibited high ACE inhibitory activity (69%) and IC50 value (3.35 mg/mL). The SDNRNQGY peptide (10 mg/mL) had ACE inhibitory activity, which was not significantly different from that of the positive control captopril (0.5 mg/mL). In addition, YPSPV in (EYGF-33) (10 mg/mL) had higher ACE inhibitory activity compared with captopril. These findings indicated a substantial potential for producing valuable peptides with antioxidant and ACE inhibitory activity from egg yolk.

  1. Metabolic fate of yolk fatty acids in the developing king penguin embryo.

    PubMed

    Groscolas, René; Fréchard, Françoise; Decrock, Frédéric; Speake, Brian K

    2003-10-01

    This study examines the metabolic fate of total and individual yolk fatty acids (FA) during the embryonic development of the king penguin, a seabird characterized by prolonged incubation (53 days) and hatching (3 days) periods, and a high n-3/n-6 polyunsaturated FA ratio in the egg. Of the approximately 15 g of total FA initially present in the egg lipid, 87% was transferred to the embryo by the time of hatching, the remaining 13% being present in the internalized yolk sac of the chick. During the whole incubation, 83% of the transferred FA was oxidized for energy, with only 17% incorporated into embryo lipids. Prehatching (days 0-49), the fat stores (triacylglycerol) accounted for 58% of the total FA incorporated into embryo lipid. During hatching (days 49-53), 40% of the FA of the fat stores was mobilized, the mobilization of individual FA being nonselective. At hatch, 53% of the arachidonic acid (20:4n-6) of the initial yolk had been incorporated into embryo lipid compared with only 15% of the total FA and 17-24% of the various n-3 polyunsaturated FA. Similarly, only 32% of the yolk's initial content of 20:4n-6 was oxidized for energy during development compared with 72% of the total FA and 58-66% of the n-3 polyunsaturated FA. The high partitioning of yolk FA toward oxidization and the intense mobilization of fat store FA during hatching most likely reflect the high energy cost of the long incubation and hatching periods of the king penguin. The preferential partitioning of 20:4n-6 into the structural lipid of the embryo in the face of its low content in the yolk may reflect the important roles of this FA in tissue function.

  2. PFOS, PFNA, and PFOA Sub-Lethal Exposure to Embryonic Zebrafish Have Different Toxicity Profiles in Terms of Morphometrics, Behavior and Gene Expression

    PubMed Central

    Jantzen, Carrie E.; Annunziato, Kate A.; Bugel, Sean M.; Cooper, Keith R.

    2016-01-01

    Polyfluorinated compounds (PFC) are a class of anthropogenic, persistent and toxic chemicals. PFCs are detected worldwide and consist of fluorinated carbon chains of varying length, terminal groups, and industrial uses. Previous zebrafish studies in the literature as well as our own studies have shown that exposure to these chemicals at a low range of concentrations (0.02 µM – 2.0 µM; 20–2000 ppb) resulted in chemical specific developmental defects and reduced post hatch survival. It was hypothesized that sub-lethal embryonic exposure to perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), or perfluorooctanoic acid (PFOA) would result in different responses with regard to morphometric, behavior, and gene expression in both yolk sac fry and larval zebrafish. Zebrafish were exposed to PFOS, PFOA, and PFNA (0.02, 0.2, 2.0 µM) for the first five days post fertilization (dpf) and analyzed for morphometrics (5 dpf, 14 dpf), targeted gene expression (5 dpf, 14 dpf), and locomotive behavior (14 dpf). All three PFCs commonly resulted in a decrease in total body length, increased tfc3a (muscle development) expression and decreased ap1s (protein transport) expression at 5dpf, and hyperactive locomotor activity 14 dpf. All other endpoints measured at both life-stage time points varied between each of the PFCs. PFOS, PFNA, and PFOA exposure resulted in significantly altered responses in terms of morphometric, locomotion, and gene expression endpoints, which could be manifested in field exposed teleosts. PMID:27058923

  3. Optical micromanipulation of nanoparticles and cells inside living zebrafish.

    PubMed

    Johansen, Patrick Lie; Fenaroli, Federico; Evensen, Lasse; Griffiths, Gareth; Koster, Gerbrand

    2016-03-21

    Regulation of biological processes is often based on physical interactions between cells and their microenvironment. To unravel how and where interactions occur, micromanipulation methods can be used that offer high-precision control over the duration, position and magnitude of interactions. However, lacking an in vivo system, micromanipulation has generally been done with cells in vitro, which may not reflect the complex in vivo situation inside multicellular organisms. Here using optical tweezers we demonstrate micromanipulation throughout the transparent zebrafish embryo. We show that different cells, as well as injected nanoparticles and bacteria can be trapped and that adhesion properties and membrane deformation of endothelium and macrophages can be analysed. This non-invasive micromanipulation inside a whole-organism gives direct insights into cell interactions that are not accessible using existing approaches. Potential applications include screening of nanoparticle-cell interactions for cancer therapy or tissue invasion studies in cancer and infection biology.

  4. Supplementation of different concentrations of Orvus Es Paste (OEP) to ostrich egg yolk lipoprotein extender improves post-thaw boar semen quality.

    PubMed

    Fraser, L; Jasiewicz, E; Kordan, W

    2014-01-01

    This study aimed to compare post-thaw quality of boar semen following freezing in an ostrich egg yolk lipoprotein (LPFo) extender supplemented with 0%, 0.25% and 0.50% Orvus Es Paste (OEP). Sperm assessments included total motility (TMOT), mitochondrial function (MF), plasma membrane integrity (PMI) and acrosome integrity (normal apical ridge, NAR). Considerable variations among boars and OEP treatments had a significant effect (P < 0.001) on post-thaw sperm characteristics. It was observed that post-thaw sperm characteristics were significantly compromised in semen samples frozen in the absence of OEP. By contrast, lactose-LPFo-glycerol extender supplemented with either 0.25% OEP or 0.50% OEP markedly enhanced post-thaw sperm characteristics. In all boars, there were no marked differences in post-thaw sperm TMOT between the freezing extenders supplemented with 0.25% and 0.50% OEP. However, a decline in the percentage of post-thaw motile spermatozoa was more pronounced in the extender supplemented with 0.50% OEP following a 120-min incubation period. Furthermore, the proportions of frozen-thawed spermatozoa with MF, PMI and NAR acrosomes varied significantly among the boars in the OEP-supplemented extenders. The findings of this study indicate that different OEP concentrations, in the presence of ostrich egg yolk lipoproteins, could have varying effects on post-thaw sperm survival.

  5. Cholesterol-lowering activity of plant sterol-egg yolk lipoprotein complex in rats.

    PubMed

    Matsuoka, Ryosuke; Muto, Ayano; Kimura, Mamoru; Hoshina, Ryosuke; Wakamatsu, Toshio; Masuda, Yasunobu

    2008-01-01

    Free plant sterols cannot be dissolved in oil or water. Using free plant sterols and egg yolks, we developed a plant sterol-egg yolk lipoprotein complex (PSY) that can be dispersed in water and considered suitable for use in processed foods. The cholesterol-lowering activity of PSY was equal to that of free plant sterols and plant sterol esters. Consumption of a freeze-dried PSY-containing omelet reduced serum and hepatic cholesterol concentrations. The results suggest that PSY has cholesterol-lowering activity equivalent to that of free plant sterols and plant sterol esters. Moreover, the cholesterol-lowering activity of PSY was maintained in processed foods.

  6. The Effects of Biopolymer Encapsulation on Total Lipids and Cholesterol in Egg Yolk during in Vitro Human Digestion

    PubMed Central

    Hur, Sun-Jin; Kim, Young-Chan; Choi, Inwook; Lee, Si-Kyung

    2013-01-01

    The purpose of this study was to examine the effect of biopolymer encapsulation on the digestion of total lipids and cholesterol in egg yolk using an in vitro human digestion model. Egg yolks were encapsulated with 1% cellulose, pectin, or chitosan. The samples were then passed through an in vitro human digestion model that simulated the composition of mouth saliva, stomach acid, and the intestinal juice of the small intestine by using a dialysis tubing system. The change in digestion of total lipids was monitored by confocal fluorescence microscopy. The digestion rate of total lipids and cholesterol in all egg yolk samples dramatically increased after in vitro human digestion. The digestion rate of total lipids and cholesterol in egg yolks encapsulated with chitosan or pectin was reduced compared to the digestion rate of total lipids and cholesterol in other egg yolk samples. Egg yolks encapsulated with pectin or chitosan had lower free fatty acid content, and lipid oxidation values than samples without biopolymer encapsulation. Moreover, the lipase activity decreased, after in vitro digestion, in egg yolks encapsulated with biopolymers. These results improve our understanding of the effects of digestion on total lipids and cholesterol in egg yolk within the gastrointestinal tract. PMID:23965957

  7. Implications of genetic selection on yolk proportion on the dry matter content of eggs in a White Leghorn population.

    PubMed

    Icken, W; Looft, C; Schellander, K; Cavero, D; Blanco, A; Schmutz, M; Preisinger, R

    2014-01-01

    1. The responses to genetic selection on yolk proportion as a technique for increasing egg dry matter content, an important criterion for the egg-product industry, was investigated in a pedigree flock of White Leghorn hens. 2. Parents were preselected on high and low yolk proportion from a base population. The absolute estimated breeding value for yolk proportion of both groups differed by 3%. The realised selection difference in dry matter content of eggs between groups was more than 1% in the analysed offspring population. 3. Heritability estimates were moderate and dry matter had a lower heritability (h(2) = 0.39) than yolk proportion (h(2) = 0.44). 4. The genetic correlation between yolk proportion and dry matter content was highly positive (rg = 0.91). Genetic correlations with egg weight were negative and would have to be compensated for in a breeding programme (rg = -0.76 with yolk proportion and rg = -0.64 with dry matter content). The genetic correlation between the laying performance and yolk proportion was rg = 0.28 and close to zero (rg = -0.05) for dry matter content. 5. Easy recording and lower undesirable correlations make yolk proportion more suitable for commercial selection compared with egg dry matter content in layer breeding.

  8. Laying-sequence-specific variation in yolk oestrogen levels, and relationship to plasma oestrogen in female zebra finches (Taeniopygia guttata)

    PubMed Central

    Williams, Tony D.; Ames, Caroline E.; Kiparissis, Yiannis; Wynne-Edwards, Katherine E.

    2005-01-01

    We investigated the relationship between plasma and yolk oestrogens in laying female zebra finches (Taeniopygia guttata) by manipulating plasma oestradiol (E2) levels, via injection of oestradiol-17β, in a sequence-specific manner to maintain chronically high plasma levels for later-developing eggs (contrasting with the endogenous pattern of decreasing plasma E2 concentrations during laying). We report systematic variation in yolk oestrogen concentrations, in relation to laying sequence, similar to that widely reported for androgenic steroids. In sham-manipulated females, yolk E2 concentrations decreased with laying sequence. However, in E2-treated females plasma E2 levels were higher during the period of rapid yolk development of later-laid eggs, compared with control females. As a consequence, we reversed the laying-sequence-specific pattern of yolk E2: in E2-treated females, yolk E2 concentrations increased with laying-sequence. In general therefore, yolk E2 levels were a direct reflection of plasma E2 levels. However, in control females there was some inter-individual variability in the endogenous pattern of plasma E2 levels through the laying cycle which could generate variation in sequence-specific patterns of yolk hormone levels even if these primarily reflect circulating steroid levels. PMID:15695208

  9. Cu₂O template synthesis of high-performance PtCu alloy yolk-shell cube catalysts for direct methanol fuel cells.

    PubMed

    Ye, Sheng-Hua; He, Xu-Jun; Ding, Liang-Xin; Pan, Zheng-Wei; Tong, Ye-Xiang; Wu, Mingmei; Li, Gao-Ren

    2014-10-21

    Novel PtCu alloy yolk-shell cubes were fabricated via the disproportionation and displacement reactions in Cu2O yolk-shell cubes, and they exhibit significantly improved catalytic activity and durability for methanol electrooxidation.

  10. Zebrafish neurobehavioral phenomics for aquatic neuropharmacology and toxicology research.

    PubMed

    Kalueff, Allan V; Echevarria, David J; Homechaudhuri, Sumit; Stewart, Adam Michael; Collier, Adam D; Kaluyeva, Aleksandra A; Li, Shaomin; Liu, Yingcong; Chen, Peirong; Wang, JiaJia; Yang, Lei; Mitra, Anisa; Pal, Subharthi; Chaudhuri, Adwitiya; Roy, Anwesha; Biswas, Missidona; Roy, Dola; Podder, Anupam; Poudel, Manoj K; Katare, Deepshikha P; Mani, Ruchi J; Kyzar, Evan J; Gaikwad, Siddharth; Nguyen, Michael; Song, Cai

    2016-01-01

    Zebrafish (Danio rerio) are rapidly emerging as an important model organism for aquatic neuropharmacology and toxicology research. The behavioral/phenotypic complexity of zebrafish allows for thorough dissection of complex human brain disorders and drug-evoked pathological states. As numerous zebrafish models become available with a wide spectrum of behavioral, genetic, and environmental methods to test novel drugs, here we discuss recent zebrafish phenomics methods to facilitate drug discovery, particularly in the field of biological psychiatry. Additionally, behavioral, neurological, and endocrine endpoints are becoming increasingly well-characterized in zebrafish, making them an inexpensive, robust and effective model for toxicology research and pharmacological screening. We also discuss zebrafish behavioral phenotypes, experimental considerations, pharmacological candidates and relevance of zebrafish neurophenomics to other 'omics' (e.g., genomic, proteomic) approaches. Finally, we critically evaluate the limitations of utilizing this model organism, and outline future strategies of research in the field of zebrafish phenomics. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Can Zebrafish be used to Identify Developmentally Neurotoxic Chemicals

    EPA Science Inventory

    Can Zebrafish be Used to Identify Developmentally Neurotoxic Chemicals? The U.S. Environmental Protection Agency is evaluating methods to screen and prioritize large numbers of chemicals for developmental neurotoxicity. We are exploring behavioral methods using zebrafish by desig...

  12. Development of the zebrafish myoseptum with emphasis on the myotendinous junction.

    PubMed

    Charvet, Benjamin; Malbouyres, Marilyne; Pagnon-Minot, Aurélie; Ruggiero, Florence; Le Guellec, Dominique

    2011-12-01

    Zebrafish myosepta connect two adjacent muscle cells and transmit muscular forces to axial structures during swimming via the myotendinous junction (MTJ). The MTJ establishes transmembrane linkages system consisting of extracellular matrix molecules (ECM) surrounding the basement membrane, cytoskeletal elements anchored to sarcolema, and all intermediate proteins that link ECM to actin filaments. Using a series of zebrafish specimens aged between 24 h post-fertilization and 2 years old, the present paper describes at the transmission electron microscope level the development of extracellular and intracellular elements of the MTJ. The transverse myoseptum development starts during the segmentation period by deposition of sparse and loosely organized collagen fibrils. During the hatching period, a link between actin filaments and sarcolemma is established. The basal lamina underlining sarcolemma is well differentiated. Later, collagen fibrils display an orthogonal orientation and fibroblast-like cells invade the myoseptal stroma. A dense network of collagen fibrils is progressively formed that both anchor myoseptal fibroblasts and sarcolemmal basement membrane. The differentiation of a functional MTJ is achieved when sarcolemma interacts with both cytoskeletal filaments and extracellular components. This solid structural link between contractile apparatus and ECM leads to sarcolemma deformations resulting in the formation of regular invaginations, and allows force transmission during muscle contraction. This paper presents the first ultrastructural atlas of the zebrafish MTJ development, which represents an useful tool to analyse the mechanisms of the myotendinous system formation and their disruption in muscle disorders.

  13. Characterization of the fusion core in zebrafish endogenous retroviral envelope protein

    SciT

    Shi, Jian; State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071; Zhang, Huaidong

    2015-05-08

    Zebrafish endogenous retrovirus (ZFERV) is the unique endogenous retrovirus in zebrafish, as yet, containing intact open reading frames of its envelope protein gene in zebrafish genome. Similarly, several envelope proteins of endogenous retroviruses in human and other mammalian animal genomes (such as syncytin-1 and 2 in human, syncytin-A and B in mouse) were identified and shown to be functional in induction of cell–cell fusion involved in placental development. ZFERV envelope protein (Env) gene appears to be also functional in vivo because it is expressible. After sequence alignment, we found ZFERV Env shares similar structural profiles with syncytin and other type Imore » viral envelopes, especially in the regions of N- and C-terminal heptad repeats (NHR and CHR) which were crucial for membrane fusion. We expressed the regions of N + C protein in the ZFERV Env (residues 459–567, including predicted NHR and CHR) to characterize the fusion core structure. We found N + C protein could form a stable coiled-coil trimer that consists of three helical NHR regions forming a central trimeric core, and three helical CHR regions packing into the grooves on the surface of the central core. The structural characterization of the fusion core revealed the possible mechanism of fusion mediated by ZFERV Env. These results gave comprehensive explanation of how the ancient virus infects the zebrafish and integrates into the genome million years ago, and showed a rational clue for discovery of physiological significance (e.g., medicate cell–cell fusion). - Highlights: • ZFERV Env shares similar structural profiles with syncytin and other type I viral envelopes. • The fusion core of ZFERV Env forms stable coiled-coil trimer including three NHRs and three CHRs. • The structural mechanism of viral entry mediated by ZFERV Env is disclosed. • The results are helpful for further discovery of physiological function of ZFERV Env in zebrafish.« less

  14. Inhibition of memory consolidation by antibodies against cell adhesion molecules after active avoidance conditioning in zebrafish.

    PubMed

    Pradel, G; Schachner, M; Schmidt, R

    1999-05-01

    Cell adhesion molecules are expected to play an important role in long-term storage of information in the central nervous system. Several of these glycoproteins, such as NCAM, L1, and the ependymins, express the HNK-1 carbohydrate structure, which is known to be involved in cell-cell and cell-matrix interactions. To investigate the contribution of the HNK-1 epitope and the secretory glycoproteins ependymins to memory formation in zebrafish (Brachydanio rerio), we developed an active avoidance conditioning paradigm. Zebrafish were trained in a shuttle-box to cross a hurdle, to avoid mild electric shocks following a conditioning light signal. One hour after acquisition of the task, zebrafish were injected intracerebroventricularly with monoclonal antibodies against the HNK-1 epitope or polyclonal antibodies against ependymins. Control fish received immunoglobulins G (IgGs) from nonimmune rat serum or the monoclonal antibody C183 against an unrelated cell-surface protein of the cyprinid brain. Two days later, injected zebrafish were tested for recall, and for quantitative evaluation a retention score (RS), ranging from 1.0 for immediate recall to 0.0, indicating no saving, was calculated. The average RS of anti-HNK-1-injected fish (RS = 0.30) and anti-ependymin-injected fish (0.24) were significantly different from the RS of uninjected fish (0.77), of controls injected with nonimmune serum IgGs (0.68), of C183-injected controls (0.78), and of overtrained fish injected with anti-HNK-1 antibodies (0.81). Anti-HNK-1 and anti-ependymin antibodies were characterized by Western blot analyses of subcellular brain fractions and immunohistochemical staining of the zebrafish optic tectum. Our data suggest that the antibodies influence cell recognition events at synaptic membranes and/or associated intracellular signaling cascades, and thereby block memory consolidation.

  15. Mixtures, Metabolites, and Mechanisms: Understanding Toxicology Using Zebrafish

    PubMed Central

    Gamse, Joshua T.

    2016-01-01

    Abstract For more than 60 years, zebrafish have been used in toxicological studies. Due to their transparency, genetic tractability, and compatibility with high-throughput screens, zebrafish embryos are uniquely suited to study the effects of pharmaceuticals and environmental insults on embryonic development, organ formation and function, and reproductive success. This special issue of Zebrafish highlights the ways zebrafish are used to investigate the toxic effects of endocrine disruptors, pesticides, and heavy metals. PMID:27618129

  16. Mixtures, Metabolites, and Mechanisms: Understanding Toxicology Using Zebrafish.

    PubMed

    Gamse, Joshua T; Gorelick, Daniel A

    2016-10-01

    For more than 60 years, zebrafish have been used in toxicological studies. Due to their transparency, genetic tractability, and compatibility with high-throughput screens, zebrafish embryos are uniquely suited to study the effects of pharmaceuticals and environmental insults on embryonic development, organ formation and function, and reproductive success. This special issue of Zebrafish highlights the ways zebrafish are used to investigate the toxic effects of endocrine disruptors, pesticides, and heavy metals.

  17. The toxicity potential of pharmaceuticals found in the Douro River estuary (Portugal)--experimental assessment using a zebrafish embryo test.

    PubMed

    Madureira, Tânia Vieira; Cruzeiro, Catarina; Rocha, Maria João; Rocha, Eduardo

    2011-09-01

    Fish embryos are a particularly vulnerable stage of development, so they represent optimal targets for screening toxicological effects of waterborne xenobiotics. Herein, the toxicity potential of two mixtures of pharmaceuticals was evaluated using a zebrafish embryo test. One of the mixtures corresponds to an environmentally realistic scenario and both have carbamazepine, fenofibric acid, propranolol, trimethoprim and sulfamethoxazole. The results evidenced morphological alterations, such as spinal deformities and yolk-sac oedemas. Moreover, heart rates decreased after both mixture exposures, e.g., at 48hpf, highest mixture versus blank control (47.8±4.9 and 55.8±3.7 beats/30s, respectively). The tail lengths also diminished significantly from 3208±145μm in blank control to 3130±126μm in highest mixture. The toxicological effects were concentration dependent. Mortality, hatching rate and the number of spontaneous movements were not affected. However, the low levels of pharmaceuticals did interfere with the normal development of zebrafish, which indicates risks for wild organisms. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Sept7b is essential for pronephric function and development of left-right asymmetry in zebrafish embryogenesis.

    PubMed

    Dash, Surjya Narayan; Lehtonen, Eero; Wasik, Anita A; Schepis, Antonino; Paavola, Jere; Panula, Pertti; Nelson, W James; Lehtonen, Sanna

    2014-04-01

    The conserved septin family of filamentous small GTPases plays important roles in mitosis, cell migration and cell morphogenesis by forming scaffolds and diffusion barriers. Recent studies in cultured cells in vitro indicate that a septin complex of septin 2, 7 and 9 is required for ciliogenesis and cilia function, but septin function in ciliogenesis in vertebrate organs in vivo is not understood. We show that sept7b is expressed in ciliated cells in different tissues during early zebrafish development. Knockdown of sept7b by using morpholino antisense oligonucleotides caused misorientation of basal bodies and cilia, reduction of apical actin and the shortening of motile cilia in Kupffer's vesicle and pronephric tubules. This resulted in pericardial and yolk sac edema, body axis curvature and hydrocephaly. Notably, in sept7b morphants we detected strong left-right asymmetry defects in the heart and lateral plate mesoderm (situs inversus), reduced fluid flow in the kidney, the formation of kidney cysts and loss of glomerular filtration barrier function. Thus, sept7b is essential during zebrafish development for pronephric function and ciliogenesis, and loss of expression of sept7b results in defects that resemble human ciliopathies.

  19. Modeling Leukemogenesis in the Zebrafish Using Genetic and Xenograft Models.

    PubMed

    Rajan, Vinothkumar; Dellaire, Graham; Berman, Jason N

    2016-01-01

    The zebrafish is a widely accepted model to study leukemia. The major advantage of studying leukemogenesis in zebrafish is attributed to its short life cycle and superior imaging capacity. This chapter highlights using transgenic- and xenograft-based models in zebrafish to study a specific leukemogenic mutation and analyze therapeutic responses in vivo.

  20. Viral Diseases in Zebrafish: What Is Known and Unknown

    PubMed Central

    Crim, Marcus J.; Riley, Lela K.

    2013-01-01

    Naturally occurring viral infections have the potential to introduce confounding variability that leads to invalid and misinterpreted data. Whereas the viral diseases of research rodents are well characterized and closely monitored, no naturally occurring viral infections have been characterized for the laboratory zebrafish (Danio rerio), an increasingly important biomedical research model. Despite the ignorance about naturally occurring zebrafish viruses, zebrafish models are rapidly expanding in areas of biomedical research where the confounding effects of unknown infectious agents present a serious concern. In addition, many zebrafish research colonies remain linked to the ornamental (pet) zebrafish trade, which can contribute to the introduction of new pathogens into research colonies, whereas mice used for research are purpose bred, with no introduction of new mice from the pet industry. Identification, characterization, and monitoring of naturally occurring viruses in zebrafish are crucial to the improvement of zebrafish health, the reduction of unwanted variability, and the continued development of the zebrafish as a model organism. This article addresses the importance of identifying and characterizing the viral diseases of zebrafish as the scope of zebrafish models expands into new research areas and also briefly addresses zebrafish susceptibility to experimental viral infection and the utility of the zebrafish as an infection and immunology model. PMID:23382345

  1. Fetal Membranes-Derived Stem Cells Microenvironment.

    PubMed

    Favaron, Phelipe Oliveira; Miglino, Maria Angelica

    2017-01-01

    Recently, the regenerative medicine has been trying to congregate different areas such as tissue engineering and cellular therapy, in order to offer effective treatments to overcome several human and veterinary medical problems. In this regard, fetal membranes have been proposed as a powerful source for obtainment of multipotent stem cells with low immunogenicity, anti-inflammatory properties and nontumorigenicity properties for the treatment of several diseases, including replacing cells lost due to tissue injuries or degenerative diseases. Morpho-physiological data have shown that fetal membranes, especially the yolk sac and amnion play different functions according to the gestational period, which are direct related to the features of the microenvironment that their cells are subject. The characteristics of the microenvironment affect or controls important cellular events involved with proliferation, division and maintenance of the undifferentiated stage or differentiation, especially acting on the extracellular matrix components. Considering the importance of the microenvironment and the diversity of embryonic and fetal membrane-derived stem cells, this chapter will addressed advances in the isolation, phenotyping, characteristics of the microenvironment, and applications of yolk sac and amniotic membrane-derived stem cells for human and veterinary regenerative medicine.

  2. Muscular contractions in the zebrafish embryo are necessary to reveal thiuram-induced notochord distortions

    SciT

    Teraoka, Hiroki; Urakawa, Satsuki; Nanba, Satomi

    2006-04-01

    Dithiocarbamates form a large group of chemicals that have numerous uses in agriculture and medicine. It has been reported that dithiocarbamates, including thiuram (tetramethylthiuram disulfide), cause wavy distortions of the notochord in zebrafish and other fish embryos. In the present study, we investigated the mechanism underlying the toxicity of thiuram in zebrafish embryos. When embryos were exposed to thiuram (2-1000 nM: 0.48-240 {mu}g/L) from 3 h post fertilization (hpf) (30% epiboly) until 24 hpf (Prim-5), all embryos develop wavy notochords, disorganized somites, and have shortened yolk sac extensions. The thiuram response was specific and did not cause growth retardation ormore » mortality at 24 hpf. The thiuram-dependent responses showed the same concentration dependence with a waterborne EC{sub 5} values of approximately 7 nM. Morphometric measurements revealed that thiuram does not affect the rate of notochord lengthening. However, the rate of overall body lengthening was significantly reduced in thiuram-exposed animals. Other dithiocarbamates, such as ziram, caused similar malformations to thiuram. While expression of genes involved in somitogenesis was not affected, the levels of notochord-specific transcripts were altered after the onset of malformations. Distortion of the notochord started precisely at 18 hpf, which is concomitant with onset of spontaneous rhythmic trunk contractions. Abolishment of spontaneous contractions using tricaine, {alpha}-bungarotoxin, and a paralytic mutant sofa potato, resulted in normal notochord morphology in the presence of thiuram. These results indicate that muscle activity is necessary to reveal the underlying functional deficit and suggest that the developmental target of dithiocarbamates impairs trunk plasticity through an unknown mechanism.« less

  3. Semen Quality of Post-Thawed Local Ram’s in Tris-Egg Yolk Extender with Different Glutathione Level

    NASA Astrophysics Data System (ADS)

    Solihati, N.; Rasad, S. D.; Setiawan, R.; Foziah, E. N.; Wigiyanti, E. T.

    2018-02-01

    The aims of this research were to find out the effect of glutathione level on semen quality of local ram and to find out the glutathione level that provide the best quality of local ram semen. This research use Completely Randomized Design (CRD) with five treatments of glutathione level (0 mM, 4 mM, 5 mM, 6 mM and 7mM) and was repeated for 10 times. Data were analyzed using analysis of varians (ANOVA) and differences between treatment was analyzed using Duncan test. The parameter were semen quality consist of motility, intact plasma membrane (IPM), abnormality, and recovery rate. Result of this research showed that glutathione level significantly (p<0.05) affect on motility, IPM, abnormality and recovery rate. Duncan test result showed that recovery rate from treatment of 5 mM glutathione level have significantly higher than other treatment, whereas for motility, IPM and abnormality were not significant different with 4 mM, and 6 mM. It is concluded that semen quality of local ram was affected by glutathione level, and the level of 5 mM in egg yolk tris extender provide the best quality of local ram semen.

  4. Effects of yolk contamination, shearing, and heating on foaming properties of fresh egg white.

    PubMed

    Wang, G; Wang, T

    2009-03-01

    A series of experiments were conducted to evaluate effects of yolk contamination, shearing, and thermal treatment on foaming properties of liquid egg white. Samples obtained from industrial processing were also evaluated. Whipping and purging methods were both used to assess their effectiveness and sensitivity in evaluating foaming. A concentration as low as 0.022% (as-is basis) of yolk contamination caused significant reductions in foaming capacity and foaming speed. The neutral lipid fraction of egg yolk caused the major detrimental effect on foaming, and phospholipids fraction did not give significant foaming reduction at a concentration as high as 0.1%. High-speed and short-time shearing caused no apparent damage but longer shearing time significantly impaired foaming. Heat-induced foaming change is a function of temperature and holding time. Foaming was significantly reduced at a temperature of 55 degrees C for 10 min, whereas it did not change up to 3 min at a heating temperature of 62 to 64 degrees C. Industrial processing steps (pumping, pipe transfer, and storage) did not produce negative effects on foaming of the final products and the controlled pasteurization was actually beneficial for good foaming performance. Therefore, yolk contamination of the egg white was the major factor in reducing foaming properties of the white protein.

  5. Measurement of Iron in Egg Yolk: An Instrumental Analysis Experiment Using Biochemical Principles

    ERIC Educational Resources Information Center

    Maloney, Kevin M.; Quiazon, Emmanuel M.; Indralingam, Ramee

    2008-01-01

    The generally accepted method to determine iron content in food is by acid digestion or dry ashing and subsequent flame atomic absorption spectrometry or inductively coupled plasma atomic emission spectrometry. We have developed an experiment that chemically extracts the iron from an egg yolk and quantifies it using UV-vis absorption…

  6. Antiproliferative Activity of Egg Yolk Peptides in Human Colon Cancer Cells.

    PubMed

    Yousr, Marwa N; Aloqbi, Akram A; Omar, Ulfat M; Howell, Nazlin K

    2017-01-01

    Egg yolk peptides were successfully prepared from egg yolk protein by-products after lecithin extraction. Defatted egg yolk protein was hydrolyzed with pepsin and pancreatin and purified by gel filtration to produce egg yolk gel filtration fraction (EYGF-33) with antiproliferative activity. The highlight of this study was that the peptide EYGF-33 (1.0 mg/ml) significantly inhibits cell viability of colon cancer cells (Caco-2) with no inhibitory effects on the viability of human colon epithelial normal cells (HCEC) after 48 h. Reduced cell viability can be explained by cell cycle arrest in the S-phase in which DNA replication normally takes place. EYGF-33 significantly enhanced the production of superoxide anions in the mitochondria of Caco-2 cells; this could activate a mitochondrial apoptotic pathway leading to typical Poly Adenosine diphosphate-ribose polymerase (PARP) cleavage as observed in the Western blot result. The induction of apoptotic cell death by EYGF-33 was supported by the externalization of phosphatidylserine (PS). However, further elucidation of the mechanism of EYGF-33-mediated apoptosis would provide further support for its use as a potential therapeutic and chemopreventive agent.

  7. Ruptured-yolk peritonitis and organochlorine residues in a royal tern

    Blus, L.J.; Locke, L.N.; Stafford, C.J.

    1977-01-01

    Ruptured-yolk peritonitis was responsible for the death of a royal tern. Lodgment of eggs in the oviduct was probably due to reverse peristalsis brought about by breakage of the thin-shelled eggs and secondary bacterial infection. The thin shells were apparently not related to the low levels of DDE and other organochlorine pollutants found in tissues and egg contents.

  8. Characterization of calcium carbonate crystals in pigeon yolk sacs with different incubation times.

    PubMed

    Song, Juan; Cheng, Haixia; Shen, Xinyu; Hu, Jingxiao; Tong, Hua

    2014-05-01

    Calcium carbonate crystals are known to form in the yolk sacs of fertile pigeon eggs at late stages of incubation. The composition and structure of these crystals were investigated, the crystallization environment was inspected, and the physical chemistry constants of the yolk fluid were determined through the incubation period. Polarized light microscopy was used to observe the generation and distribution of calcium carbonate crystals in the yolk sac. In addition, X-ray diffraction was employed to analyze the composition and crystal phase of the yolk sac. A decalcification and deproteination method was established to analyze the ultrastructure and composition of the crystals, as well as the internal relationship between inorganic and organic phases of the crystals. Additionally, scanning electron microscopy, transmission electron microscopy, X-ray energy dispersive spectroscopy, and Fourier transform infrared spectroscopy were used to evaluate the characteristics of the crystals. Our results demonstrated that the calcium carbonate crystals were mainly composed of vaterite and calcite, with vaterite being the major component. Vaterite, a type of biomaterial generated by an organic template control, presented as a concentric hierarchical spherical structure. The organic nature of the biomaterial prevented vaterite from transforming into calcite, which is more thermodynamically stable than vaterite. Additionally, the configuration, size, and aggregation of vaterite were also mediated by the organic template. This bio-vaterite was found during the incubation period and is valuable in calcium transport during embryonic development. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Ovarian mixed germ cell tumor with yolk sac and teratomatous components in a dog.

    PubMed

    Robinson, Nicholas A; Manivel, J Carlos; Olson, Erik J

    2013-05-01

    Mixed germ cell tumors of the ovary have rarely been reported in veterinary species. A 3-year-old intact female Labrador Retriever dog was presented for lethargy, abdominal distention, and a midabdominal mass. An exploratory laparotomy revealed a large (23 cm in diameter) left ovarian tumor and multiple small (2-3 cm in diameter) pale tan masses on the peritoneum and abdominal surface of the diaphragm. Histological examination of the left ovary revealed a mixed germ cell tumor with a yolk sac component with rare Schiller-Duval bodies and a teratomatous component comprised primarily of neural differentiation. The abdominal metastases were solely comprised of the yolk sac component. The yolk sac component was diffusely immunopositive for cytokeratin with scattered cells reactive for α-fetoprotein and placental alkaline phosphatase. Within the teratomatous component, the neuropil was diffusely immunopositive for S100, neuron-specific enolase, and neurofilaments with a few glial fibrillary acidic protein immunopositive cells. Ovarian germ cell tumors may be pure and consist of only 1 germ cell element or may be mixed and include more than 1 germ cell element, such as teratoma and yolk sac tumor.

  10. Enzymatic enrichment of egg-yolk phosphatidylcholine with alpha-linolenic acid.

    PubMed

    Chojnacka, A; Gładkowski, W; Kiełbowicz, G; Wawrzeńczyk, C

    2009-05-01

    alpha-Linolenic acid (ALA) was incorporated at 28% into the sn-1 position of egg-yolk phospatidylcholine using Novozyme 435 in one-step transesterification process. Using phospholipase A(2) in a two-step process gave 25% incorporation of ALA into the sn-2 position.

  11. Thermal transitions in the low-density lipoprotein and lipids of the egg yolk of hens.

    PubMed

    Smith, M B; Back, J F

    1975-05-22

    1. Differential sanning calorimetry and light-scattering have been used to investigate temperature-dependent transitions in low-density lipoprotein and in lipids from hens' egg yolk. Yolks of different fatty acid composition were obtained by varying the dietary lipid and by adding methyl sterculate to the hen's diet. 2. Lipoprotein solutions in 50 percent glycerol/water gave characteristic melting curves between -25 degrees C and 50 degrees C, and on cooling showed increases in light-scattering between 10 degrees C and -20 degrees C. The temperatures at which major changes occurred depended on the proportions of saturated and unsaturated fatty acids. 3. The thermal transitions in the intact lipoprotein in glycerol solution were reversible, but with marked hysteresis. Lipid extracted from the lipoprotein did not show temperature hystersis but the transition heats and melting curves similar to those of the intact lipoprotein. The results support the hypothesis of a "lipid-core" structure for low-density lipoproteins. 4. Scanning calorimetry of egg-yolk lecithins indicated a strong dependence of transition temperature on water content in the rane 3 percent-20 percent water. A rise in the mid-temperature of the liquid-crystalline to gel transition as the water content is lowered on freezing may be the primary event in the irreversible gelation of egg yolk and aggregation of lipoprotein.

  12. Penguin chicks benefit from elevated yolk androgen levels under sibling competition.

    PubMed

    Poisbleau, Maud; Müller, Wendt; Carslake, David; Demongin, Laurent; Groothuis, Ton G G; Van Camp, Jeff; Eens, Marcel

    2012-01-01

    Crested penguins (genus Eudyptes) have a peculiar hatching pattern, with the first-laid egg (A-egg) hatching after the second-laid egg (B-egg) and chicks from A-eggs typically having a much lower survival probability. Maternal yolk androgens have been suggested to contribute to the competitive superiority of the B-chick in southern rockhopper penguins Eudyptes chrysocome, given their important role in mediating sibling competition in other species. We therefore increased the yolk androgen levels in freshly-laid eggs and examined the consequences for sibling competition--via effects on embryonic developmental times, chick growth and early survival. We placed one androgen-treated egg and one control egg into each foster nest, matching them for mass, laying date and laying order. The androgen treatment did not significantly affect embryonic developmental times or chick measurements at hatching. However, elevated yolk androgen levels benefitted chick growth in interaction with the number of siblings in a brood. Chicks from androgen-treated eggs had faster growth in the presence of a sibling than chicks from control eggs. Under these circumstances they also had a higher survival probability. Thus maternal androgens appear to reinforce the observed hatching pattern, facilitating brood reduction. This contrasts to most previous studies in other species where yolk androgens have been shown to compensate for the negative consequences of delayed hatching within the brood hierarchy.

  13. Yolk@Shell Nanoarchitectures with Bimetallic Nanocores-Synthesis and Electrocatalytic Applications.

    PubMed

    Guiet, Amandine; Unmüssig, Tobias; Göbel, Caren; Vainio, Ulla; Wollgarten, Markus; Driess, Matthias; Schlaad, Helmut; Polte, Jörg; Fischer, Anna

    2016-10-10

    In the present paper, we demonstrate a versatile approach for the one-pot synthesis of metal oxide yolk@shell nanostructures filled with bimetallic nanocores. This novel approach is based on the principles of hydrophobic nanoreactor soft-templating and is exemplified for the synthesis of various AgAu NP @tin-rich ITO (AgAu@ITO TR ) yolk@shell nanomaterials. Hydrophobic nanoreactor soft-templating thereby takes advantage of polystyrene-block-poly(4-vinylpiridine) inverse micelles as two-compartment nanoreactor template, in which the core and the shell of the micelles serve as metal and metal oxide precursor reservoir, respectively. The composition, size and number of AuAg bimetallic nanoparticles incorporated within the ITO TR yolk@shell can easily be tuned. The conductivity of the ITO TR shell and the bimetallic composition of the AuAg nanoparticles, the as-synthesized AuAg NP @ITO TR yolk@shell materials could be used as efficient electrocatalysts for electrochemical glucose oxidation with improved onset potential when compared to their gold counterpart.

  14. Enantioselectivity in Developmental Toxicity of rac-metalaxyl and R-metalaxyl in Zebrafish (Danio rerio) Embryo.

    PubMed

    Zhang, Yinjun; Zhang, Yi; Chen, An; Zhang, Wei; Chen, Hao; Zhang, Quan

    2016-06-01

    Enantioselectivity of chiral pesticides in environmental safety has attracted more and more attention. In this study, we evaluated the enantioselective toxicity of rac-metalaxyl and R-metalaxyl to zebrafish (Danio rerio) embryos through various malformations including pericardial edema, yolk sac edema, crooked body, and short tails. The results showed that there were significant differences in toxicity to zebrafish embryos caused by rac-metalaxyl and R-metalaxyl, and the LC50 s at 96 h are 416.41 (353.91, 499.29) mg · L(-1) and 320.650 (279.80, 363.46) mg · L(-1) , respectively. In order to explore the possible mechanism of the development defects, the genes involved in the hypothalamic-pituitary-gonadal axis (vtg1, vtg2, cyp17, cyp19a, cyp19b) and hypothalamic-pituitary-thyroid axis (dio1, dio2, nis, tg, tpo) were quantified by quantitative real-time polymerase chain reaction (qRT-PCR). The results revealed that there were no significant differences in the expression of vtg1, vtg2, cyp17, cyp19a, and cyp19b after exposure to rac-metalaxyl. However, the expression of vtg1, cyp19a, and cyp19b decreased significantly after exposure to R-metalaxyl. And likewise, rac-metalaxyl only caused the upregulation of dio2, while R-metalaxyl suppressed the expression of dio1 and tpo and induced the expression of dio2 and nis. The change of gene expression may cause the enantioselectivity in developmental toxicity in zebrafish embryo. The data provided here will be helpful for us to comprehensively understand the potential ecological risks of the currently used chiral fungicides. Chirality 28:489-494, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Cardio-respirometry disruption in zebrafish (Danio rerio) embryos exposed to hydraulic fracturing flowback and produced water.

    PubMed

    Folkerts, Erik J; Blewett, Tamzin A; He, Yuhe; Goss, Greg G

    2017-12-01

    Hydraulic fracturing to extract oil and natural gas reserves is an increasing practice in many international energy sectors. Hydraulic fracturing flowback and produced water (FPW) is a hyper saline wastewater returned to the surface from a fractured well containing chemical species present in the initial fracturing fluid, geogenic contaminants, and potentially newly synthesized chemicals formed in the fracturing well environment. However, information on FPW toxicological mechanisms of action remain largely unknown. Both cardiotoxic and respirometric responses were explored in zebrafish (Danio rerio) embryos after either an acute sediment-free (FPW-SF) or raw/sediment containing (FPW-S) fraction exposure of 24 and 48 h at 2.5% and 5% dilutions. A 48 h exposure to either FPW fraction in 24-72 h post fertilization zebrafish embryos significantly increased occurrences of pericardial edema, yolk-sac edema, and tail/spine curvature. In contrast, larval heart rates significantly decreased after FPW fraction exposures. FPW-S, but not FPW-SF, at 2.5% doses significantly reduced embryonic respiration/metabolic rates (MO 2 ), while for 5% FPW, both fractions reduced MO 2 . Expression of select cardiac genes were also significantly altered in each FPW exposure group, implicating a cardiovascular system compromise as the potential cause for reduced embryonic MO 2 . Collectively, these results support our hypothesis that organics are major contributors to cardiac and respiratory responses to FPW exposure in zebrafish embryos. Our study is the first to investigate cardiac and respiratory sub-lethal effects of FPW exposure, demonstrating that FPW effects extend beyond initial osmotic stressors and verifies the use of respirometry as a potential marker for FPW exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Endotoxin molecule lipopolysaccharide-induced zebrafish inflammation model: a novel screening method for anti-inflammatory drugs.

    PubMed

    Yang, Li-Ling; Wang, Guo-Quan; Yang, Li-Mei; Huang, Zhi-Bing; Zhang, Wen-Qing; Yu, Lin-Zhong

    2014-02-21

    Lipopolysaccharide (LPS), an endotoxin molecule, has been used to induce inflammatory responses. In this study, LPS was used to establish an in vivo inflammation model in zebrafish for drug screening. We present an experimental method that conveniently and rapidly assesses the anti-inflammatory properties of drugs. The yolks of 3-day post-fertilization (dpf) larvae were injected with 0.5 mg/mL LPS to induce fatal inflammation. After LPS stimulation, macrophages were tracked by NR and SB staining and neutrophil migration was observed using the MPO:GFP line. Larval mortality was used as the primary end-point. Expression levels of key cytokines involved in the inflammatory response including IL-1β, IL-6, and TNF-α, were measured using quantitative reverse transcription polymerase chain reaction (RT-PCR). Macrophages and neutrophils were both recruited to the LPS-injected site during the inflammatory response. Mortality was increased by LPS in a dose-dependent manner within 48 h. Analyses of IL-1β, IL-6, and TNF-α expression levels revealed the upregulation of the inflammatory response in the LPS-injected larvae. Further, the anti-inflammatory activity of chlorogenic acid (CA) was evaluated in this zebrafish model to screen for anti-inflammatory drugs. A preliminary result showed that CA revealed a similar effect as the corticosteroid dexamethasone (DEX), which was used as a positive control, by inhibiting macrophage and neutrophil recruitment to the LPS site and improving survival. Our results suggest that this zebrafish screening model could be applied to study inflammation-mediated diseases. Moreover, the Traditional Chinese Medicine CA displays potential anti-inflammatory activity.

  17. Production of Androgenetic Zebrafish (Danio Rerio)

    PubMed Central

    Corley-Smith, G. E.; Lim, C. J.; Brandhorst, B. P.

    1996-01-01

    To help investigate the evolutionary origin of the imprinting (parent-of-origin mono-allelic expression) of paternal genes observed in mammals, we constructed haploid and diploid androgenetic zebrafish (Danio rerio). Haploid androgenotes were produced by fertilizing eggs that had been X-ray irradiated to eliminate the maternal genome. Subsequent inhibition of the first mitotic division of haploid androgenotes by heat shock produced diploid androgenotes. The lack of inheritance of maternal-specific DNA markers (RAPD and SSR) by putative diploid and haploid androgenotes confirmed the androgenetic origin of their genomes. Marker analysis was performed on 18 putative androgenotes (five diploids and 13 haploids) from six families. None of 157 maternal-specific RAPD markers analyzed, some of which were apparently homozygous, were passed on to any of these putative androgenotes. A mean of 7.7 maternal-specific markers were assessed per family. The survival of androgenetic zebrafish suggests that if paternal imprinting occurs in zebrafish, it does not result in essential genes being inactivated when their expression is required for development. Production of haploid androgenotes can be used to determine the meiotic recombination rate in male zebrafish. Androgenesis may also provide useful information about the mechanism of sex determination in zebrafish. PMID:8846903

  18. The zebrafish genome: a review and msx gene case study.

    PubMed

    Postlethwait, J H

    2006-01-01

    Zebrafish is one of several important teleost models for understanding principles of vertebrate developmental, molecular, organismal, genetic, evolutionary, and genomic biology. Efficient investigation of the molecular genetic basis of induced mutations depends on knowledge of the zebrafish genome. Principles of zebrafish genomic analysis, including gene mapping, ortholog identification, conservation of syntenies, genome duplication, and evolution of duplicate gene function are discussed here using as a case study the zebrafish msxa, msxb, msxc, msxd, and msxe genes, which together constitute zebrafish orthologs of tetrapod Msx1, Msx2, and Msx3. Genomic analysis suggests orthologs for this difficult to understand group of paralogs.

  19. Monitoring Toxic Ionic Liquids in Zebrafish ( Danio rerio) with Desorption Electrospray Ionization Mass Spectrometry Imaging (DESI-MSI)

    NASA Astrophysics Data System (ADS)

    Perez, Consuelo J.; Tata, Alessandra; de Campos, Michel L.; Peng, Chun; Ifa, Demian R.

    2017-06-01

    Ambient mass spectrometry imaging has become an increasingly powerful technique for the direct analysis of biological tissues in the open environment with minimal sample preparation and fast analysis times. In this study, we introduce desorption electrospray ionization mass spectrometry imaging (DESI-MSI) as a novel, rapid, and sensitive approach to localize the accumulation of a mildly toxic ionic liquid (IL), AMMOENG 130 in zebrafish ( Danio rerio). The work demonstrates that DESI-MSI has the potential to rapidly monitor the accumulation of IL pollutants in aquatic organisms. AMMOENG 130 is a quaternary ammonium-based IL reported to be broadly used as a surfactant in commercialized detergents. It is known to exhibit acute toxicity to zebrafish causing extensive damage to gill secondary lamellae and increasing membrane permeability. Zebrafish were exposed to the IL in a static 96-h exposure study in concentrations near the LC50 of 1.25, 2.5, and 5.0 mg/L. DESI-MS analysis of zebrafish gills demonstrated the appearance of a dealkylated AMMOENG 130 metabolite in the lowest concentration of exposure identified by a high resolution hybrid LTQ-Orbitrap mass spectrometer as the trimethylstearylammonium ion, [C21H46N]+. With DESI-MSI, the accumulation of AMMOENG 130 and its dealkylated metabolite in zebrafish tissue was found in the nervous and respiratory systems. AMMOENG 130 and the metabolite were capable of penetrating the blood brain barrier of the fish with significant accumulation in the brain. Hence, we report for the first time the simultaneous characterization, distribution, and metabolism of a toxic IL in whole body zebrafish analyzed by DESI-MSI. This ambient mass spectrometry imaging technique shows great promise for the direct analysis of biological tissues to qualitatively monitor foreign, toxic, and persistent compounds in aquatic organisms from the environment. [Figure not available: see fulltext.

  20. The impact of model peptides on structural and dynamic properties of egg yolk lecithin liposomes - experimental and DFT studies.

    PubMed

    Wałęsa, Roksana; Man, Dariusz; Engel, Grzegorz; Siodłak, Dawid; Kupka, Teobald; Ptak, Tomasz; Broda, Małgorzata A

    2015-07-01

    Electron spin resonance (ESR), (1) H-NMR, voltage and resistance experiments were performed to explore structural and dynamic changes of Egg Yolk Lecithin (EYL) bilayer upon addition of model peptides. Two of them are phenylalanine (Phe) derivatives, Ac-Phe-NHMe (1) and Ac-Phe-NMe2 (2), and the third one, Ac-(Z)-ΔPhe-NMe2 (3), is a derivative of (Z)-α,β-dehydrophenylalanine. The ESR results revealed that all compounds reduced the fluidity of liposome's membrane, and the highest activity was observed for compound 2 with N-methylated C-terminal amide bond (Ac-Phe-NMe2 ). This compound, being the most hydrophobic, penetrates easily through biological membranes. This was also observed in voltage and resistance studies. (1) H-NMR studies provided a sound evidence on H-bond interactions between the studied diamides and lecithin polar head. The most significant changes in H-atom chemical shifts and spin-lattice relaxation times T1 were observed for compound 1. Our experimental studies were supported by theoretical calculations. Complexes EYLAc-Phe-NMe2 and EYLAc-(Z)-ΔPhe-NMe2 , stabilized by NH⋅⋅⋅O or/and CH⋅⋅⋅O H-bonds were created and optimized at M06-2X/6-31G(d) level of theory in vacuo and in H2 O environment. According to our molecular-modeling studies, the most probable lecithin site of H-bond interaction with studied diamides is the negatively charged O-atom in phosphate group which acts as H-atom acceptor. Moreover, the highest binding energy to hydrocarbon chains were observed in the case of Ac-Phe-NMe2 (2). Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  1. Effects of lipid extraction on stable isotope ratios in avian egg yolk: Is arithmetic correction a reliable alternative?

    Oppel, S.; Federer, R.N.; O'Brien, D. M.; Powell, A.N.; Hollmén, Tuula E.

    2010-01-01

    Many studies of nutrient allocation to egg production in birds use stable isotope ratios of egg yolk to identify the origin of nutrients. Dry egg yolk contains >50% lipids, which are known to be depleted in 13C. Currently, researchers remove lipids from egg yolk using a chemical lipid-extraction procedure before analyzing the isotopic composition of protein in egg yolk. We examined the effects of chemical lipid extraction on ??13C, ??15N, and ??34S of avian egg yolk and explored the utility of an arithmetic lipid correction model to adjust whole yolk ??13C for lipid content. We analyzed the dried yolk of 15 captive Spectacled Eider (Somateriafischeri) and 20 wild King Eider (S. spectabilis) eggs, both as whole yolk and after lipid extraction with a 2:1 chloroform:methanol solution. We found that chemical lipid extraction leads to an increase of (mean ?? SD) 3.3 ?? 1.1% in ??13C, 1.1 ?? 0.5% in ??15N, and 2.3 ?? 1.1% in ??34S. Arithmetic lipid correction provided accurate values for lipid-extracted S13C in captive Spectacled Eiders fed on a homogeneous high-quality diet. However, arithmetic lipid correction was unreliable for wild King Eiders, likely because of their differential incorporation of macronutrients from isotopically distinct environments during migration. For that reason, we caution against applying arithmetic lipid correction to the whole yolk ??13C of migratory birds, because these methods assume that all egg macronutrients are derived from the same dietary sources. ?? 2010 The American Ornithologists' Union.

  2. Zebrafish heart failure models: opportunities and challenges.

    PubMed

    Shi, Xingjuan; Chen, Ru; Zhang, Yu; Yun, Junghwa; Brand-Arzamendi, Koroboshka; Liu, Xiangdong; Wen, Xiao-Yan

    2018-05-03

    Heart failure is a complex pathophysiological syndrome of pumping functional failure that results from injury, infection or toxin-induced damage on the myocardium, as well as genetic influence. Gene mutations associated with cardiomyopathies can lead to various pathologies of heart failure. In recent years, zebrafish, Danio rerio, has emerged as an excellent model to study human cardiovascular diseases such as congenital heart defects, cardiomyopathy, and preclinical development of drugs targeting these diseases. In this review, we will first summarize zebrafish genetic models of heart failure arose from cardiomyopathy, which is caused by mutations in sarcomere, calcium or mitochondrial-associated genes. Moreover, we outline zebrafish heart failure models triggered by chemical compounds. Elucidation of these models will improve the understanding of the mechanism of pathogenesis and provide potential targets for novel therapies.

  3. Midline signals regulate retinal neurogenesis in zebrafish.

    PubMed

    Masai, I; Stemple, D L; Okamoto, H; Wilson, S W

    2000-08-01

    In zebrafish, neuronal differentiation progresses across the retina in a pattern that is reminiscent of the neurogenic wave that sweeps across the developing eye in Drosophila. We show that expression of a zebrafish homolog of Drosophila atonal, ath5, sweeps across the eye predicting the wave of neuronal differentiation. By analyzing the regulation of ath5 expression, we have elucidated the mechanisms that regulate initiation and spread of neurogenesis in the retina. ath5 expression is lost in Nodal pathway mutant embryos lacking axial tissues that include the prechordal plate. A likely role for axial tissue is to induce optic stalk cells that subsequently regulate ath5 expression. Our results suggest that a series of inductive events, initiated from the prechordal plate and progressing from the optic stalks, regulates the spread of neuronal differentiation across the zebrafish retina.

  4. Tributyltin and Zebrafish: Swimming in Dangerous Water

    PubMed Central

    Berto-Júnior, Clemilson; de Carvalho, Denise Pires; Soares, Paula; Miranda-Alves, Leandro

    2018-01-01

    Zebrafish has been established as a reliable biological model with important insertion in academy (morphologic, biochemical, and pathophysiological studies) and pharmaceutical industry (toxicology and drug development) due to its molecular complexity and similar systems biology that recapitulate those from other organisms. Considering the toxicological aspects, many efforts using zebrafish models are being done in order to elucidate the effects of endocrine disruptors, and some of them are focused on tributyltin (TBT) and its mechanism of action. TBT is an antifouling agent applied in ship’s hull that is constantly released into the water and absorbed by marine organisms, leading to bioaccumulation and biomagnification effects. Thus, several findings of malformations and changes in the normal biochemical and physiologic aspects of these marine animals have been related to TBT contamination. In the present review, we have compiled the most significant studies related to TBT effects in zebrafish, also taking into consideration the effects found in other study models. PMID:29692757

  5. 15 years of zebrafish chemical screening

    PubMed Central

    Rennekamp, Andrew J.; Peterson, Randall T.

    2015-01-01

    In 2000, the first chemical screen using living zebrafish in a multi-well plate was reported. Since then, more than 60 additional screens have been published describing whole-organism drug and pathway discovery projects in zebrafish. To investigate the scope of the work reported in the last 14 years and to identify trends in the field, we analyzed the discovery strategies of 64 primary research articles from the literature. We found that zebrafish screens have expanded beyond the use of developmental phenotypes to include behavioral, cardiac, metabolic, proliferative and regenerative endpoints. Additionally, many creative strategies have been used to uncover the mechanisms of action of new small molecules including chemical phenocopy, genetic phenocopy, mutant rescue, and spatial localization strategies. PMID:25461724

  6. Culturable Gut Microbiota Diversity in Zebrafish

    PubMed Central

    Sørby, Jan Roger Torp; Aleström, Peter; Sørum, Henning

    2012-01-01

    Abstract The zebrafish (Danio rerio) is an increasingly used laboratory animal model in basic biology and biomedicine, novel drug development, and toxicology. The wide use has increased the demand for optimized husbandry protocols to ensure animal health care and welfare. The knowledge about the correlation between culturable zebrafish intestinal microbiota and health in relation to environmental factors and management procedures is very limited. A semi-quantitative level of growth of individual types of bacteria was determined and associated with sampling points. A total of 72 TAB line zebrafish from four laboratories (Labs A–D) in the Zebrafish Network Norway were used. Diagnostic was based on traditional bacterial culture methods and biochemical characterization using commercial kits, followed by 16S rDNA gene sequencing from pure subcultures. Also selected Gram-negative isolates were analyzed for antibiotic susceptibility to 8 different antibiotics. A total of 13 morphologically different bacterial species were the most prevalent: Aeromonas hydrophila, Aeromonas sobria, Vibrio parahaemolyticus, Photobacterium damselae, Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas luteola, Comamonas testosteroni, Ochrobactrum anthropi, Staphylococcus cohnii, Staphylococcus epidermidis, Staphylococcus capitis, and Staphylococcus warneri. Only Lab B had significantly higher levels of total bacterial growth (OR=2.03), whereas numbers from Lab C (OR=1.01) and Lab D (OR=1.12) were found to be similar to the baseline Lab A. Sexually immature individuals had a significantly higher level of harvested total bacterial growth than mature fish (OR=0.82), no statistically significant differences were found between male and female fish (OR=1.01), and the posterior intestinal segment demonstrated a higher degree of culturable bacteria than the anterior segment (OR=4.1). Multiple antibiotic (>3) resistance was observed in 17% of the strains. We propose that a rapid

  7. Culturable gut microbiota diversity in zebrafish.

    PubMed

    Cantas, Leon; Sørby, Jan Roger Torp; Aleström, Peter; Sørum, Henning

    2012-03-01

    The zebrafish (Danio rerio) is an increasingly used laboratory animal model in basic biology and biomedicine, novel drug development, and toxicology. The wide use has increased the demand for optimized husbandry protocols to ensure animal health care and welfare. The knowledge about the correlation between culturable zebrafish intestinal microbiota and health in relation to environmental factors and management procedures is very limited. A semi-quantitative level of growth of individual types of bacteria was determined and associated with sampling points. A total of 72 TAB line zebrafish from four laboratories (Labs A-D) in the Zebrafish Network Norway were used. Diagnostic was based on traditional bacterial culture methods and biochemical characterization using commercial kits, followed by 16S rDNA gene sequencing from pure subcultures. Also selected Gram-negative isolates were analyzed for antibiotic susceptibility to 8 different antibiotics. A total of 13 morphologically different bacterial species were the most prevalent: Aeromonas hydrophila, Aeromonas sobria, Vibrio parahaemolyticus, Photobacterium damselae, Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas luteola, Comamonas testosteroni, Ochrobactrum anthropi, Staphylococcus cohnii, Staphylococcus epidermidis, Staphylococcus capitis, and Staphylococcus warneri. Only Lab B had significantly higher levels of total bacterial growth (OR=2.03), whereas numbers from Lab C (OR=1.01) and Lab D (OR=1.12) were found to be similar to the baseline Lab A. Sexually immature individuals had a significantly higher level of harvested total bacterial growth than mature fish (OR=0.82), no statistically significant differences were found between male and female fish (OR=1.01), and the posterior intestinal segment demonstrated a higher degree of culturable bacteria than the anterior segment (OR=4.1). Multiple antibiotic (>3) resistance was observed in 17% of the strains. We propose that a rapid conventional

  8. Zebrafish embryo developmental toxicology assay.

    PubMed

    Panzica-Kelly, Julieta M; Zhang, Cindy X; Augustine-Rauch, Karen

    2012-01-01

    A promising in vitro zebrafish developmental toxicology assay was generated to test compounds for their teratogenic potential. The assay's predictivity is approximately 87% in AB strain fish (Brannen KC et al., Birth Defects Res B Dev Reprod Toxicol 89:66-77, 2010). The procedure entails exposing dechorionated gastrulation-stage embryos to a range of compound concentrations for 5 days throughout embryonic and larva development. The larvae are evaluated for viability in order to identify an LC25 (the compound concentration in which 25% lethality is observed) and morphological anomalies using a numerical score system to identify the NOAEL (no observed adverse effect level). These values are used to calculate the teratogenic index (LC25/NOAEL ratio) of each compound. If the teratogenic index is equal to or greater than 10 then the compound is classified as a teratogen, and if the ratio is less than 10 then the compound is classified as a nonteratogen (Brannen KC et al., Birth Defects Res B Dev Reprod Toxicol 89:66-77, 2010).

  9. Glyphosate induces neurotoxicity in zebrafish.

    PubMed

    Roy, Nicole M; Carneiro, Bruno; Ochs, Jeremy

    2016-03-01

    Glyphosate based herbicides (GBH) like Roundup(®) are used extensively in agriculture as well as in urban and rural settings as a broad spectrum herbicide. Its mechanism of action was thought to be specific only to plants and thus considered safe and non-toxic. However, mounting evidence suggests that GBHs may not be as safe as once thought as initial studies in frogs suggest that GBHs may be teratogenic. Here we utilize the zebrafish vertebrate model system to study early effects of glyphosate exposure using technical grade glyphosate and the Roundup(®) Classic formulation. We find morphological abnormalities including cephalic and eye reductions and a loss of delineated brain ventricles. Concomitant with structural changes in the developing brain, using in situ hybridization analysis, we detect decreases in genes expressed in the eye, fore and midbrain regions of the brain including pax2, pax6, otx2 and ephA4. However, we do not detect changes in hindbrain expression domains of ephA4 nor exclusive hindbrain markers krox-20 and hoxb1a. Additionally, using a Retinoic Acid (RA) mediated reporter transgenic, we detect no alterations in the RA expression domains in the hindbrain and spinal cord, but do detect a loss of expression in the retina. We conclude that glyphosate and the Roundup(®) formulation is developmentally toxic to the forebrain and midbrain but does not affect the hindbrain after 24 h exposure. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Developmental toxicity and alteration of gene expression in zebrafish embryos exposed to PFOS

    SciT

    Shi Xiongjie; Graduate School of the Chinese Academy of Sciences, Beijing 100039; Du Yongbing

    2008-07-01

    Perfluorooctanesulfonate (PFOS) is a persistent organic pollutant, the potential toxicity of which is causing great concern. In the present study, we employed zebrafish embryos to investigate the developmental toxicity of this compound. Four-hour post-fertilization (hpf) zebrafish embryos were exposed to 0.1, 0.5, 1, 3 and 5 mg/L PFOS. Hatching was delayed and hatching rates as well as larval survivorship were significantly reduced after the embryos were exposed to 1, 3 and 5 mg/L PFOS until 132 hpf. The fry displayed gross developmental malformations, including epiboly deformities, hypopigmentation, yolk sac edema, tail and heart malformations and spinal curvature upon exposure tomore » PFOS concentrations of 1 mg/L or greater. Growth (body length) was significantly reduced in the 3 and 5 mg/L PFOS-treated groups. To test whether developmental malformation was mediated via apoptosis, flow cytometry analysis of DNA content, acridine orange staining and TUNEL assay was used. These techniques indicated that more apoptotic cells were present in the PFOS-treated embryos than in the control embryos. Certain genes related to cell apoptosis, p53 and Bax, were both significantly up-regulated upon exposure to all the concentrations tested. In addition, we investigated the effects of PFOS on marker genes related to early thyroid development (hhex and pax8) and genes regulating the balance of androgens and estrogens (cyp19a and cyp19b). For thyroid development, the expression of hhex was significantly up-regulated at all concentrations tested, whereas pax8 expression was significantly up-regulated only upon exposure to lower concentrations of PFOS (0.1, 0.5, 1 mg/L). The expression of cyp19a and of cyp19b was significantly down-regulated at all exposure concentrations. The overall results indicated that zebrafish embryos constitute a reliable model for testing the developmental toxicity of PFOS, and the gene expression patterns in the embryos were able to reveal some

  11. Oestrogen-related receptor α is required for transepithelial H+ secretion in zebrafish

    PubMed Central

    Guh, Ying-Jey; Yang, Chao-Yew; Liu, Sian-Tai; Huang, Chang-Jen

    2016-01-01

    Oestrogen-related receptor α (ERRα) is an orphan nuclear receptor which is important for adaptive metabolic responses under conditions of increased energy demand, such as cold, exercise and fasting. Importantly, metabolism under these conditions is usually accompanied by elevated production of organic acids, which may threaten the body acid–base status. Although ERRα is known to help regulate ion transport by the renal epithelia, its role in the transport of acid–base equivalents remains unknown. Here, we tested the hypothesis that ERRα is involved in acid–base regulation mechanisms by using zebrafish as the model to examine the effects of ERRα on transepithelial H+ secretion. ERRα is abundantly expressed in H+-pump-rich cells (HR cells), a group of ionocytes responsible for H+ secretion in the skin of developing embryos, and its expression is stimulated by acidic (pH 4) environments. Knockdown of ERRα impairs both basal and low pH-induced H+ secretion in the yolk-sac skin, which is accompanied by decreased expression of H+-secreting-related transporters. The effect of ERRα on H+ secretion is achieved through regulating both the total number of HR cells and the function of individual HR cells. These results demonstrate, for the first time, that ERRα is required for transepithelial H+ secretion for systemic acid–base homeostasis. PMID:26911965

  12. Mitigation in Multiple Effects of Graphene Oxide Toxicity in Zebrafish Embryogenesis Driven by Humic Acid.

    PubMed

    Chen, Yuming; Ren, Chaoxiu; Ouyang, Shaohu; Hu, Xiangang; Zhou, Qixing

    2015-08-18

    Graphene oxide (GO) is a widely used carbonaceous nanomaterial. To date, the influence of natural organic matter (NOM) on GO toxicity in aquatic vertebrates has not been reported. During zebrafish embryogenesis, GO induced a significant hatching delay and cardiac edema. The intensive interactions of GO with the chorion induces damage to chorion protuberances, excessive generation of (•)OH, and changes in protein secondary structure. In contrast, humic acid (HA), a ubiquitous form of NOM, significantly relieved the above adverse effects. HA reduced the interactions between GO and the chorion and mitigated chorion damage by regulating the morphology, structures, and surface negative charges of GO. HA also altered the uptake and deposition of GO and decreased the aggregation of GO in embryonic yolk cells and deep layer cells. Furthermore, HA mitigated the mitochondrial damage and oxidative stress induced by GO. This work reveals a feasible antidotal mechanism for GO in the presence of NOM and avoids overestimating the risks of GO in the natural environment.

  13. Structural effects of naphthalimide-based fluorescent sensor for hydrogen sulfide and imaging in live zebrafish

    NASA Astrophysics Data System (ADS)

    Choi, Seon-Ae; Park, Chul Soon; Kwon, Oh Seok; Giong, Hoi-Khoanh; Lee, Jeong-Soo; Ha, Tai Hwan; Lee, Chang-Soo

    2016-05-01

    Hydrogen sulfide (H2S) is an important biological messenger, but few biologically-compatible methods are available for its detection in aqueous solution. Herein, we report a highly water-soluble naphthalimide-based fluorescent probe (L1), which is a highly versatile building unit that absorbs and emits at long wavelengths and is selective for hydrogen sulfide over cysteine, glutathione, and other reactive sulfur, nitrogen, and oxygen species in aqueous solution. We describe turn-on fluorescent probes based on azide group reduction on the fluorogenic ‘naphthalene’ moiety to fluorescent amines and intracellular hydrogen sulfide detection without the use of an organic solvent. L1 and L2 were synthetically modified to functional groups with comparable solubility on the N-imide site, showing a marked change in turn-on fluorescent intensity in response to hydrogen sulfide in both PBS buffer and living cells. The probes were readily employed to assess intracellular hydrogen sulfide level changes by imaging endogenous hydrogen sulfide signal in RAW264.7 cells incubated with L1 and L2. Expanding the use of L1 to complex and heterogeneous biological settings, we successfully visualized hydrogen sulfide detection in the yolk, brain and spinal cord of living zebrafish embryos, thereby providing a powerful approach for live imaging for investigating chemical signaling in complex multicellular systems.

  14. Evaluation of toxicological endpoints in female zebrafish after bisphenol A exposure.

    PubMed

    Molina, Ana M; Abril, Nieves; Morales-Prieto, Noelia; Monterde, José G; Lora, Antonio J; Ayala, Nahúm; Moyano, Rosario

    2018-02-01

    Given the importance of bisphenol A (BPA) as a xenoestrogen and its potential effects on human and animal health, we evaluated BPA exposure's short-term effects on follicular development, yolk protein vitellogenin (VTG) production and aromatase expression in female zebrafish. Histological modifications were observed along with increased presence of atretic follicles. Whole-body VTG concentration increased with the dose of BPA exposure. In contrast, expression of Cyp19a mRNA in the ovaries of BPA-exposed fish exhibited an apparent non-monotonic response curve, marked by downregulation at 1 μg/L BPA, upregulation at 10 μg/L BPA, and a return to downregulation at 100 μg/L BPA and higher doses. Ovaries only exhibited significant increases in follicular atresia and VTG concentration after exposure to 100 μg/L BPA and higher doses. Ovarian histopathology, aromatase Cyp19a transcript levels and whole-body VTG protein abundance may be good biomarkers for early detection of environmental BPA exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Distribution of selenium in zebrafish larvae after exposure to organic and inorganic selenium forms.

    PubMed

    Dolgova, N V; Hackett, M J; MacDonald, T C; Nehzati, S; James, A K; Krone, P H; George, G N; Pickering, I J

    2016-03-01

    Selenium is an essential micronutrient for many organisms, and in vertebrates has a variety of roles associated with protection from reactive oxygen species. Over the past two decades there have been conflicting reports upon human health benefits and detriments arising from consumption of selenium dietary supplements. Thus, early studies report a decrease in the incidence of certain types of cancer, whereas subsequent studies did not observe any anti-cancer effect, and adverse effects such as increased risks for type 2 diabetes have been reported. A possible contributing factor may be that different chemical forms of selenium were used in different studies. Using larval stage zebrafish (Danio rerio) as a model organism, we report a comparison of the toxicities and tissue selenium distributions of four different chemical forms of selenium. We find that the organic forms of selenium tested (Se-methyl-l-selenocysteine and l-selenomethionine) show considerably more toxicity than inorganic forms (selenite and selenate), and that this appears to be correlated with the level of bioaccumulation. Despite differences in concentrations, the tissue specific pattern of selenium accumulation was similar for the chemical forms tested; selenium was found to be highly concentrated in pigment (melanin) containing tissues especially for the organic selenium treatments, with lower concentrations in eye lens, yolk sac and heart. These results suggest that pigmented tissues might serve as a storage reservoir for selenium.

  16. Influence of the Enteric Nervous System on Gut Motility Patterns in Zebrafish

    NASA Astrophysics Data System (ADS)

    Baker, Ryan; Ganz, Julia; Melancon, Ellie; Eisen, Judith; Parthasarathy, Raghuveer

    The enteric nervous system (ENS), composed of diverse neuronal subtypes and glia, regulates essential gut functions including motility, secretion, and homeostasis. In humans and animals, decreased numbers of enteric neurons lead to a variety of types of gut dysfunction. However, surprisingly little is known about how the number, position, or subtype of enteric neurons affect the regulation of gut peristalsis, due to the lack of good model systems and the lack of tools for the quantitative characterization of gut motion. We have therefore developed a method of quantitative spatiotemporal mapping using differential interference contrast microscopy and particle image velocimetry, and have applied this to investigate intestinal dynamics in normal and mutant larval zebrafish. From movies of gut motility, we obtain a velocity vector field representative of gut motion, from which we can quantify parameters relating to gut peristalsis such as frequency, wave speed, deformation amplitudes, wave duration, and non-linearity of waves. We show that mutants with reduced neuron number have contractions that are more regular in time and reduced in amplitude compared to wild-type (normal) fish. We also show that feeding fish before their yolk is consumed leads to stronger motility patterns. We acknowledge support from NIH awards P50 GM098911 and P01 HD022486.

  17. Dimethyl sulfoxide (DMSO) exacerbates cisplatin-induced sensory hair cell death in zebrafish (Danio rerio).

    PubMed

    Uribe, Phillip M; Mueller, Melissa A; Gleichman, Julia S; Kramer, Matthew D; Wang, Qi; Sibrian-Vazquez, Martha; Strongin, Robert M; Steyger, Peter S; Cotanche, Douglas A; Matsui, Jonathan I

    2013-01-01

    Inner ear sensory hair cells die following exposure to aminoglycoside antibiotics or chemotherapeutics like cisplatin, leading to permanent auditory and/or balance deficits in humans. Zebrafish (Danio rerio) are used to study drug-induced sensory hair cell death since their hair cells are similar in structure and function to those found in humans. We developed a cisplatin dose-response curve using a transgenic line of zebrafish that expresses membrane-targeted green fluorescent protein under the control of the Brn3c promoter/enhancer. Recently, several small molecule screens have been conducted using zebrafish to identify potential pharmacological agents that could be used to protect sensory hair cells in the presence of ototoxic drugs. Dimethyl sulfoxide (DMSO) is typically used as a solvent for many pharmacological agents in sensory hair cell cytotoxicity assays. Serendipitously, we found that DMSO potentiated the effects of cisplatin and killed more sensory hair cells than treatment with cisplatin alone. Yet, DMSO alone did not kill hair cells. We did not observe the synergistic effects of DMSO with the ototoxic aminoglycoside antibiotic neomycin. Cisplatin treatment with other commonly used organic solvents (i.e. ethanol, methanol, and polyethylene glycol 400) also did not result in increased cell death compared to cisplatin treatment alone. Thus, caution should be exercised when interpreting data generated from small molecule screens since many compounds are dissolved in DMSO.

  18. Dimethyl Sulfoxide (DMSO) Exacerbates Cisplatin-induced Sensory Hair Cell Death in Zebrafish (Danio rerio)

    PubMed Central

    Gleichman, Julia S.; Kramer, Matthew D.; Wang, Qi; Sibrian-Vazquez, Martha; Strongin, Robert M.; Steyger, Peter S.; Cotanche, Douglas A.; Matsui, Jonathan I.

    2013-01-01

    Inner ear sensory hair cells die following exposure to aminoglycoside antibiotics or chemotherapeutics like cisplatin, leading to permanent auditory and/or balance deficits in humans. Zebrafish (Danio rerio) are used to study drug-induced sensory hair cell death since their hair cells are similar in structure and function to those found in humans. We developed a cisplatin dose-response curve using a transgenic line of zebrafish that expresses membrane-targeted green fluorescent protein under the control of the Brn3c promoter/enhancer. Recently, several small molecule screens have been conducted using zebrafish to identify potential pharmacological agents that could be used to protect sensory hair cells in the presence of ototoxic drugs. Dimethyl sulfoxide (DMSO) is typically used as a solvent for many pharmacological agents in sensory hair cell cytotoxicity assays. Serendipitously, we found that DMSO potentiated the effects of cisplatin and killed more sensory hair cells than treatment with cisplatin alone. Yet, DMSO alone did not kill hair cells. We did not observe the synergistic effects of DMSO with the ototoxic aminoglycoside antibiotic neomycin. Cisplatin treatment with other commonly used organic solvents (i.e. ethanol, methanol, and polyethylene glycol 400) also did not result in increased cell death compared to cisplatin treatment alone. Thus, caution should be exercised when interpreting data generated from small molecule screens since many compounds are dissolved in DMSO. PMID:23383324

  19. Defective calmodulin-dependent rapid apical endocytosis in zebrafish sensory hair cell mutants.

    PubMed

    Seiler, C; Nicolson, T

    1999-11-15

    Vertebrate mechanosensory hair cells contain a narrow "pericuticular" zone which is densely populated with small vesicles between the cuticular plate and cellular junctions near the apical surface. The presence of many cytoplasmic vesicles suggests that the apical surface of hair cells has a high turnover rate. The significance of intense membrane trafficking at the apical surface is not known. Using a marker of endocytosis, the styryl dye FM1-43, this report shows that rapid apical endocytosis in zebrafish lateral line sensory hair cells is calcium and calmodulin dependent and is partially blocked by the presence of amiloride and dihydrostreptomycin, known inhibitors of mechanotransduction channels. As seen in lateral line hair cells, sensory hair cells within the larval otic capsule also exhibit rapid apical endocytosis. Defects in internalization of the dye in both lateral line and inner ear hair cells were found in five zebrafish auditory/vestibular mutants: sputnik, mariner, orbiter, mercury, and skylab. In addition, lateral line hair cells in these mutants were not sensitive to prolonged exposure to streptomycin, which is toxic to hair cells. The presence of endocytic defects in the majority of zebrafish mechanosensory mutants points to a important role of apical endocytosis in hair cell function. Copyright 1999 John Wiley & Sons, Inc.

  20. Cftr controls lumen expansion and function of Kupffer’s vesicle in zebrafish

    PubMed Central

    Navis, Adam; Marjoram, Lindsay; Bagnat, Michel

    2013-01-01

    Regulated fluid secretion is crucial for the function of most organs. In vertebrates, the chloride channel cystic fibrosis transmembrane conductance regulator (CFTR) is a master regulator of fluid secretion. Although the biophysical properties of CFTR have been well characterized in vitro, little is known about its in vivo role during development. Here, we investigated the function of Cftr during zebrafish development by generating several cftr mutant alleles using TAL effector nucleases. We found that loss of cftr function leads to organ laterality defects. In zebrafish, left-right (LR) asymmetry requires cilia-driven fluid flow within the lumen of Kupffer’s vesicle (KV). Using live imaging we found that KV morphogenesis is disrupted in cftr mutants. Loss of Cftr-mediated fluid secretion impairs KV lumen expansion leading to defects in organ laterality. Using bacterial artificial chromosome recombineering, we generated transgenic fish expressing functional Cftr fusion proteins with fluorescent tags under the control of the cftr promoter. The transgenes completely rescued the cftr mutant phenotype. Live imaging of these transgenic lines showed that Cftr is localized to the apical membrane of the epithelial cells in KV during lumen formation. Pharmacological stimulation of Cftr-dependent fluid secretion led to an expansion of the KV lumen. Conversely, inhibition of ion gradient formation impaired KV lumen inflation. Interestingly, cilia formation and motility in KV were not affected, suggesting that fluid secretion and flow are independently controlled in KV. These findings uncover a new role for cftr in KV morphogenesis and function during zebrafish development. PMID:23487313

  1. Yolk-platelet crystals in three ancient bony fishes: Polypterus bichir (Polypteri), Amia calva L., and Lepisosteus osseus (L.) (Holostei).

    PubMed

    Lange, R H; Grodziński, Z; Kilarski, W

    1982-01-01

    Yolk-platelet crystals in Amia calva L., Lepisosteus osseus (L.) and Polypterus bichir have orthorhombic features with unit-cell dimensions a = 8.3 ... 8.8 nm, b = 16.4 ... 16.9 nm and c = 18.6 ... 19.8 nm as determined in electron-diffracted patterns of fixed, epoxy-resin embedded and thin-sectioned material. Electron-diffraction patterns, crystal projections and the above unit-cell data make them extremely similar to the orthorhombic yolk-platelet crystals known for amphibians and teleosts. This observation fills a gap in yolk-platelet research and supports the view that the general architecture of yolk platelets has been conserved for nearly 400 million years. It follows that the peculiar platelet architecture itself has physiological significance.

  2. Detecting Developmental Neurotoxicants Using Zebrafish Embryos

    EPA Science Inventory

    As part of EPA’s program on the screening and prioritization of chemicals for developmental neurotoxicity, a rapid, cost-effective in vivo vertebrate screen is being developed using an alternative species approach. Zebrafish (Danio rerio), a small freshwater fish with external f...

  3. Teaching Stress Physiology Using Zebrafish ("Danio Rerio")

    ERIC Educational Resources Information Center

    Cooper, Michael; Dhawale, Shree; Mustafa, Ahmed

    2009-01-01

    A straightforward and inexpensive laboratory experiment is presented that investigates the physiological stress response of zebrafish after a 5 degree C increase in water temperature. This experiment is designed for an undergraduate physiology lab and allows students to learn the scientific method and relevant laboratory techniques without causing…

  4. Zebrafish in Toxicology and Environmental Health.

    PubMed

    Bambino, Kathryn; Chu, Jaime

    2017-01-01

    As manufacturing processes and development of new synthetic compounds increase to keep pace with the expanding global demand, environmental health, and the effects of toxicant exposure are emerging as critical public health concerns. Additionally, chemicals that naturally occur in the environment, such as metals, have profound effects on human and animal health. Many of these compounds are in the news: lead, arsenic, and endocrine disruptors such as bisphenol A have all been widely publicized as causing disease or damage to humans and wildlife in recent years. Despite the widespread appreciation that environmental toxins can be harmful, there is limited understanding of how many toxins cause disease. Zebrafish are at the forefront of toxicology research; this system has been widely used as a tool to detect toxins in water samples and to investigate the mechanisms of action of environmental toxins and their related diseases. The benefits of zebrafish for studying vertebrate development are equally useful for studying teratogens. Here, we review how zebrafish are being used both to detect the presence of some toxins as well as to identify how environmental exposures affect human health and disease. We focus on areas where zebrafish have been most effectively used in ecotoxicology and in environmental health, including investigation of exposures to endocrine disruptors, industrial waste byproducts, and arsenic. © 2017 Elsevier Inc. All rights reserved.

  5. Behavorial assessments of larval zebrafish neurotoxicology

    EPA Science Inventory

    Fishes have long been a popular organism in ecotoxicology research, and are increasingly used in human health research as an alternative animal model for chemical screening. Our laboratory incorporates a zebrafish (Danio rerio) embryo/larval assay to screen chemicals for developm...

  6. Functional and Structural Characterization of Zebrafish ASC.

    PubMed

    Li, Yajuan; Huang, Yi; Cao, Xiaocong; Yin, Xueying; Jin, Xiangyu; Liu, Sheng; Jiang, Jiansheng; Jiang, Wei; Xiao, Tsan Sam; Zhou, Rongbin; Cai, Gang; Hu, Bing; Jin, Tengchuan

    2018-05-23

    The zebrafish genome encodes homologs for most of the proteins involved in inflammatory pathways; however, the molecular components and activation mechanisms of fish inflammasomes are largely unknown. ASC (apoptosis-associated speck-like protein containing a caspase-recruitment domain (CARD)) is the only adaptor involved in the formation of multiple types of inflammasomes. Here, we demonstrate that zASC is also involved in inflammasome activation in zebrafish. When overexpressed in vitro and in vivo in zebrafish, both the zASC and zASC pyrin domain (PYD) proteins form speck and filament structures. Importantly, the crystal structures of the N-terminal PYD and C-terminal CARD of zebrafish ASC were determined independently as two separate entities fused to maltose-binding protein (MBP). Structure-guided mutagenesis revealed the functional relevance of the PYD hydrophilic surface found in the crystal lattice. Finally, the fish caspase-1 homolog Caspy, but not the caspase-4/11 homolog Caspy2, interacts with zASC through homotypic PYD-PYD interactions, which differ from those in mammals. These observations establish the conserved and unique structural/functional features of the zASC-dependent inflammasome pathway. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  7. An outbreak of Plesimonus Shigelloides in Zebrafish

    Plesiomonas shigelloides is a flagellated, gram-negative rod that is an emergent pathogen associated with human gastroenteritis. Recently, we experienced a disease outbreak in zebrafish that were obtained from a commercial source. Fourteen days after being held at 27°C in our flow-through quarantine...

  8. Habenular kisspeptin modulates fear in the zebrafish

    PubMed Central

    Ogawa, Satoshi; Nathan, Fatima M.; Parhar, Ishwar S.

    2014-01-01

    Kisspeptin, a neuropeptide encoded by the KISS1/Kiss1, and its cognate G protein-coupled receptor, GPR54 (kisspeptin receptor, Kiss-R), are critical for the control of reproduction in vertebrates. We have previously identified two kisspeptin genes (kiss1 and kiss2) in the zebrafish, of which kiss1 neurons are located in the habenula, which project to the median raphe. kiss2 neurons are located in the hypothalamic nucleus and send axonal projections to gonadotropin-releasing hormone neurons and regulate reproductive functions. However, the physiological significance of the Kiss1 expressed in the habenula remains unknown. Here we demonstrate the role of habenular Kiss1 in alarm substance (AS)-induced fear response in the zebrafish. We found that AS-evoked fear experience significantly reduces kiss1 and serotonin-related genes (plasmacytoma expressed transcript 1 and solute carrier family 6, member 4) in the zebrafish. Furthermore, Kiss1 administration suppressed the AS-evoked fear response. To further evaluate the role of Kiss1 in fear response, zebrafish Kiss1 peptide was conjugated to saporin (SAP) to selectively inactivate Kiss-R1-expressing neurons. The Kiss1-SAP injection significantly reduced Kiss1 immunoreactivity and c-fos mRNA in the habenula and the raphe compared with control. Furthermore, 3 d after Kiss1-SAP injection, the fish had a significantly reduced AS-evoked fear response. These findings provide an insight into the role of the habenular kisspeptin system in inhibiting fear. PMID:24567386

  9. Axonal regeneration in zebrafish spinal cord

    PubMed Central

    Hui, Subhra Prakash

    2018-01-01

    Abstract In the present review we discuss two interrelated events—axonal damage and repair—known to occur after spinal cord injury (SCI) in the zebrafish. Adult zebrafish are capable of regenerating axonal tracts and can restore full functionality after SCI. Unlike fish, axon regeneration in the adult mammalian central nervous system is extremely limited. As a consequence of an injury there is very little repair of disengaged axons and therefore functional deficit persists after SCI in adult mammals. In contrast, peripheral nervous system axons readily regenerate following injury and hence allow functional recovery both in mammals and fish. A better mechanistic understanding of these three scenarios could provide a more comprehensive insight into the success or failure of axonal regeneration after SCI. This review summarizes the present understanding of the cellular and molecular basis of axonal regeneration, in both the peripheral nervous system and the central nervous system, and large scale gene expression analysis is used to focus on different events during regeneration. The discovery and identification of genes involved in zebrafish spinal cord regeneration and subsequent functional experimentation will provide more insight into the endogenous mechanism of myelination and remyelination. Furthermore, precise knowledge of the mechanism underlying the extraordinary axonal regeneration process in zebrafish will also allow us to unravel the potential therapeutic strategies to be implemented for enhancing regrowth and remyelination of axons in mammals. PMID:29721326

  10. Zebrafish in Toxicology and Environmental Health

    PubMed Central

    Bambino, Kathryn; Chu, Jaime

    2018-01-01

    As manufacturing processes and development of new synthetic compounds increase to keep pace with the expanding global demand, environmental health, and the effects of toxicant exposure are emerging as critical public health concerns. Additionally, chemicals that naturally occur in the environment, such as metals, have profound effects on human and animal health. Many of these compounds are in the news: lead, arsenic, and endocrine disruptors such as bisphenol A have all been widely publicized as causing disease or damage to humans and wildlife in recent years. Despite the widespread appreciation that environmental toxins can be harmful, there is limited understanding of how many toxins cause disease. Zebrafish are at the forefront of toxicology research; this system has been widely used as a tool to detect toxins in water samples and to investigate the mechanisms of action of environmental toxins and their related diseases. The benefits of zebrafish for studying vertebrate development are equally useful for studying teratogens. Here, we review how zebrafish are being used both to detect the presence of some toxins as well as to identify how environmental exposures affect human health and disease. We focus on areas where zebrafish have been most effectively used in ecotoxicology and in environmental health, including investigation of exposures to endocrine disruptors, industrial waste byproducts, and arsenic. PMID:28335863

  11. Nanomaterial Toxicity Screening in Developing Zebrafish Embryos

    EPA Science Inventory

    To assess nanomaterial vertebrate toxicity, a high-content screening assay was created using developing zebrafish, Danio rerio. This included a diverse group of nanomaterials (n=42 total) ranging from metallic (Ag, Au) and metal oxide (CeO2, CuO, TiO2, ZnO) nanoparticles, to non...

  12. Axonal regeneration in zebrafish spinal cord.

    PubMed

    Ghosh, Sukla; Hui, Subhra Prakash

    2018-03-01

    In the present review we discuss two interrelated events-axonal damage and repair-known to occur after spinal cord injury (SCI) in the zebrafish. Adult zebrafish are capable of regenerating axonal tracts and can restore full functionality after SCI. Unlike fish, axon regeneration in the adult mammalian central nervous system is extremely limited. As a consequence of an injury there is very little repair of disengaged axons and therefore functional deficit persists after SCI in adult mammals. In contrast, peripheral nervous system axons readily regenerate following injury and hence allow functional recovery both in mammals and fish. A better mechanistic understanding of these three scenarios could provide a more comprehensive insight into the success or failure of axonal regeneration after SCI. This review summarizes the present understanding of the cellular and molecular basis of axonal regeneration, in both the peripheral nervous system and the central nervous system, and large scale gene expression analysis is used to focus on different events during regeneration. The discovery and identification of genes involved in zebrafish spinal cord regeneration and subsequent functional experimentation will provide more insight into the endogenous mechanism of myelination and remyelination. Furthermore, precise knowledge of the mechanism underlying the extraordinary axonal regeneration process in zebrafish will also allow us to unravel the potential therapeutic strategies to be implemented for enhancing regrowth and remyelination of axons in mammals.

  13. Zebrafish Locomotor Responses Predict Irritant Potential of ...

    EPA Pesticide Factsheets

    Over the past few decades, the drying and warming trends of global climate change have increased wildland fire (WF) season length, as well as geographic area impacted. Consequently, exposures to WF fine particulate matter (PM2.5; aerodynamic diameter <2.5 µm) are likely to increase in frequency and duration, contributing to a growing public health burden. Given the influence of fuel type and combustion conditions on WFPM2.5 composition, there is pressing need to identify the biomass fuel sources and emission constituents that drive toxicity. Previously, we reported the utility of 6-day post-fertilization (dpf) zebrafish larvae in evaluating diesel exhaust PM-induced irritation, demonstrating responses analogous to those in mammals. In the present study, combustions, separated by smoldering or flaming conditions, of pine needles, red oak, pine, eucalyptus, and peat were achieved using an automated tube furnace paired with a cryo-trapping apparatus to collect condensates of emissions. The condensates were extracted and prepared for use in zebrafish assays. We hypothesized that 1) the extractable organic fractions of biomass smoke PM will elicit dose-dependent irritant responses in 6-dpf zebrafish larvae, and 2) the relative potencies will vary across biomass emissions, potentially driven by varying chemical composition of fuel sources. Six-dpf zebrafish (n= 28-32/group) were exposed acutely to PM extracts (5 concentrations; 0.3-30 µg/ml; half-log intervals) and

  14. Illuminating Phagocyte Biology: The View from Zebrafish.

    PubMed

    Huang, Cong; Niethammer, Philipp

    2016-07-25

    Many phagocyte behaviors, including vascular rolling and adhesion, migration, and oxidative bursting, are better measured in seconds or minutes than hours or days. Zebrafish is ideally suited for imaging such rapid biology within the intact animal. We discuss how this model has revealed unique insights into various aspects of phagocyte physiology. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Evaluation of Shiga toxin 2e-specific chicken egg yolk immunoglobulin: production and neutralization activity.

    PubMed

    Arimitsu, Hideyuki; Sasaki, Keiko; Kohda, Tomoko; Shimizu, Toshiyasu; Tsuji, Takao

    2014-11-01

    Chicken egg yolk immunoglobulin (IgY) against Shiga toxin 2e (Stx2e), a major cause of swine edema disease, was prepared to evaluate its possible clinical applications. The titer of Stx2e-specific IgY in egg yolk derived from three chickens that had been immunized with an Stx2e toxoid increased 2 weeks after primary immunization and remained high until 90 days after this immunization. Anti-Stx2e IgY was found to neutralize the toxicity of Stx2e by reacting with its A and B subunits, indicating that IgY is a cost-effective agent to develop for prophylactic foods or diagnosis kits for edema disease. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.

  16. [Clear cell carcinoma of the ovary simulating a yolk sac tumor].

    PubMed

    Bahri, Ibticem; Boudawara, Tahya; Khabir, Abdelmajid; Beyrouti, Mohamed Issam; Frikha, Mounir; Jlidi, Rachid

    2003-04-01

    Clear cell carcinoma (CCC) of the ovary is uncommon. In young patients, this tumor may simulate a yolk sac tumor. In this case, the morphologic distinction between these tumors is often difficult but the immunohistochemical staining for CA125 and alpha foeto protein (AFP) and the response to chemotherapy are particularly helpful to resolve this problem of differential diagnosis. We report a case of a 17 year old patient who was operated for a tumor of the right ovary. The diagnosis of a yolk sac tumor was first suggested. However, because of the non response to chemotherapy, a second laparotomy was performed; the definitive pathologic examination concluded to the diagnosis of a CCC of the ovary. The young age and the immunohistochemical staining for AFP are unusual and misleading features for a CCC. Our objective about this particular case is to discuss the anatomoclinical aspects of the CCC of the ovary and to prove the role of immunohistochemistry in the differential diagnosis.

  17. Relationships between yolk androgens and nest density, laying date, and laying order in Western Burrowing Owls (Athene cunicularia hypugaea)

    Welty, J.L.; Belthoff, J.R.; Egbert, J.; Schwabl, H.

    2012-01-01

    Increases in yolk androgens within and among avian clutches have been correlated with decreased incubation time, increased aggression within a nest, increased begging behaviour, decreased immune response, and decreased life span. Although the mechanisms that lead to variability in yolk androgens within and between clutches are not completely known, yolk androgens can be a function of both social and environmental conditions. We were interested in if and how nesting density, laying date, and laying order influenced yolk androgens in Western Burrowing Owls (Athene cunicularia hypugaea (Bonaparte, 1825)) in which nest density varies considerably. In 2006 and 2007, we used radioimmunoassay to quantify the concentrations of testosterone, 5a-dihydrotestosterone, and androstenedione in the egg yolks from one early and one latelaid egg in 47 nests of Burrowing Owls located in the Morley Nelson Snake River Birds of Prey National Conservation Area in southern Idaho. Nesting density had no detectable effect on yolk androgens. Yolk androgens varied temporally and peaked in the middle of the laying season while being low before and after this time period. Within nests, late-laid eggs had higher testosterone and dihydrotestosterone than early-laid eggs; adrostendione exhibited a similar pattern in one but not both years of our study. It is possible that the seasonal pattern in yolk androgens that we observed is related to aspects of mate quality for females or declining chances of fledging success for later nesting females, whereas rises in egg androgens between early and late eggs within clutches could reflect a mechanism to assist nestlings from late-laid eggs that hatch one to several days after their siblings to better compete for resources within the nest or promote survival in the presence of larger siblings.

  18. Egg yolk-free Baird-Parker medium for the accelerated enumeration of foodborne Staphylococcus aureus.

    PubMed Central

    Lachica, R V

    1984-01-01

    A simplified procedure is described for the accelerated enumeration of foodborne Staphylococcus aureus. This involves the replacement of egg yolk in the Baird-Parker medium with Tween 80 and MgCl2. These compounds, along with pyruvate, allow the recovery of stressed cells of S. aureus on a medium which contains potassium tellurite, LiCl, and glycine as selective agents. Black colonies are identified as S. aureus by the simplified thermonuclease test. PMID:6542337

  19. Comparing sugar type supplementation for cryopreservation of boar semen in egg yolk based extender.

    PubMed

    Malo, C; Gil, L; Gonzalez, N; Cano, R; de Blas, I; Espinosa, E

    2010-08-01

    Cryopreservation of boar semen is still considered suboptimal due to lower fertility when compared to fresh semen. The aim of this study was to evaluate the effects of the addition of different sugars (lactose, trehalose and glucose) on boar spermatozoa cryopreserved in an egg yolk based extender. Ejaculates were collected from a boar previously selected and semen samples were processed using the straw freezing procedure. In experiment 1, subsamples of semen were frozen in three different extenders: recommended lactose egg yolk extender (LEY); trehalose egg yolk extender (TEY) and glucose egg yolk extender (GEY). Sperm quality was assessed for motility, viability, acrosome integrity and hypoosmotic swelling test response upon collection, after freezing and thawing and then every hour for 3h. Results showed that total motility at 1 and 3h, progressive motility at 3h, positive hypoosmotic response at 2 and 3h and acrosome integrity at all times were significantly improved when trehalose was added to the extender. In experiment 2, sugar influence was also demonstrated in vitro fertilization. A total of 1691 oocytes were in vitro matured and inseminated with frozen-thawed sperm at 2000:1 sperm:oocyte ratio and coincubated for 6h. Presumptive zygotes were cultured in NCSU-23 medium to assess fertilization parameters and embryo development. Both penetration and monospermy rates were significantly higher for trehalose frozen semen. A significant increase was observed in efficiency and blastocyst formation rates from TEY to the other groups. Our results demonstrated that trehalose extender enhances spermatozoa viability and its in vitro fertilization parameters in boar ejaculates with good sperm freezability. Further studies are necessary to assess the impact of sugars on the entire population. (c) 2010 Elsevier Inc. All rights reserved.

  20. Effect of meiotic maturation on yolk platelet lipids from Bufo arenarum oocytes.

    PubMed

    Buschiazzo, Jorgelina; Alonso, Telma Susana

    2005-09-01

    Progesterone induces the resumption of meiosis in Bufo arenarum full-grown arrested oocytes through a nongenomic mechanism called meiotic maturation. Growing evidence indicates that lipids are involved in the maturation process. They are mainly located in yolk platelets, the principal organelles of amphibian oocytes. The aim of the present study was to analyze the effect of progesterone-induced maturation on lipids from B. arenarum yolk platelets. Ovarian oocytes, manually obtained, were incubated with progesterone to induce maturation. Yolk platelets were isolated by centrifugation at low velocity. Lipids were separated by thin-layer chromatography. For compositional analysis, they were derivatized by methanolysis, and were identified and quantified in a gas-liquid chromatograph. Phospholipid content decreased in progesterone-treated oocytes, mainly as a result of a decrease at the level of phosphatidylcholine (PC). The turnover of this lipid is considered crucial for the completion of meiosis. Sphingomyelin also underwent a decrease that could be related to the important role of ceramide as an inducer of germinal vesicle breakdown. Maturation effect on fatty acid composition registered significant changes in PC whose saturated fatty acids increased. A net increase in arachidonic acid was observed in phosphatidylserine after progesterone treatment. The contents of total triacylglycerols and diacylglycerols were not significantly modified by hormone effect while free fatty acids underwent a significant increase as a result of polyunsaturated fatty acids increase. Altogether, our results demonstrate that yolk platelet lipids are involved in the resumption of the meiotic cell cycle, thus suggesting that these organelles participate in a dynamic role during amphibian development. (c) 2005 Wiley-Liss, Inc.

  1. Characterization of vitellogenin and its derived yolk proteins in cloudy catshark (Scyliorhinus torazame).

    PubMed

    Yamane, Kodai; Yagai, Tomoki; Nishimiya, Osamu; Sugawara, Rieko; Amano, Haruna; Fujita, Toshiaki; Hiramatsu, Naoshi; Todo, Takashi; Matsubara, Takahiro; Hara, Akihiko

    2013-04-01

    Elasmobranchs (sharks and rays) exhibit unique reproductive characteristics and, in contrast to the situation in teleosts, very little is known about the identity, structure and physical characteristics of their egg yolk proteins. The aims of this study were to (1) detect and purify the vitellogenin (Vtg; egg yolk precursor) and yolk proteins (YPs) of the cloudy catshark (Scyliorhinus torazame), (2) examine the relationships between Vtg and YPs and (3) characterize and classify the deduced primary structure of the Vtg transcript (vtg). The apparent molecular weights of purified Vtg and putative Vtg-related YPs (lipovitellin: Lv, phosvitin: Pv) were determined by gel filtration and were ~560, >669 and ~58 kDa, respectively. Following SDS-PAGE, these purified products (i.e., Vtg, Lv and Pv) appeared as bands of ~210, ~110 and ~22 kDa, respectively. On Western blots, antisera against purified Vtg, Lv and Pv recognized the ~210 kDa Vtg band. Catshark Pv, in contrast to teleost Pvs, had a very low serine content. The catshark Vtg cDNA sequence (vtg) appeared to contain an open-reading frame consisting of domains encoding Lv, Pv and β'-component (β'-c). A phylogenetic analysis, with a consideration of genome duplication events, placed catshark vtg into the 'vtgAB type.' It is concluded that at least a single major type of Vtg protein, which is transcribed and translated from catshark vtgAB gene, is the precursor of three egg yolk proteins (Lv, Pv and β'-c) in catshark.

  2. Functionally conserved cis-regulatory elements of COL18A1 identified through zebrafish transgenesis.

    PubMed

    Kague, Erika; Bessling, Seneca L; Lee, Josephine; Hu, Gui; Passos-Bueno, Maria Rita; Fisher, Shannon

    2010-01-15

    Type XVIII collagen is a component of basement membranes, and expressed prominently in the eye, blood vessels, liver, and the central nervous system. Homozygous mutations in COL18A1 lead to Knobloch Syndrome, characterized by ocular defects and occipital encephalocele. However, relatively little has been described on the role of type XVIII collagen in development, and nothing is known about the regulation of its tissue-specific expression pattern. We have used zebrafish transgenesis to identify and characterize cis-regulatory sequences controlling expression of the human gene. Candidate enhancers were selected from non-coding sequence associated with COL18A1 based on sequence conservation among mammals. Although these displayed no overt conservation with orthologous zebrafish sequences, four regions nonetheless acted as tissue-specific transcriptional enhancers in the zebrafish embryo, and together recapitulated the major aspects of col18a1 expression. Additional post-hoc computational analysis on positive enhancer sequences revealed alignments between mammalian and teleost sequences, which we hypothesize predict the corresponding zebrafish enhancers; for one of these, we demonstrate functional overlap with the orthologous human enhancer sequence. Our results provide important insight into the biological function and regulation of COL18A1, and point to additional sequences that may contribute to complex diseases involving COL18A1. More generally, we show that combining functional data with targeted analyses for phylogenetic conservation can reveal conserved cis-regulatory elements in the large number of cases where computational alignment alone falls short. Copyright 2009 Elsevier Inc. All rights reserved.

  3. [Specific odor component produced by Mycobacterium lepraemurium on Ogawa yolk medium].

    PubMed

    Mori, T; Aishima, T

    1992-11-01

    When Mycobacterium lepraemurium is grown on the 1% Ogawa yolk medium, it produces a specific odor. This odor was not observed in other easily cultivable acid-fast bacilli. Therefore, identification of the components responsible for the specific odor produced by M. lepraemurium was attempted. The odor components were extracted for overnight with sterilized and distilled water from the Ogawa yolk medium on which M. lepraemurium had been cultivated for two months. The odor components in the extract was adsorbed on refined charcoal. After washing with distilled water for three times, the charcoal was dried. Then the odor components were eluted from the charcoal with ethanol and the eluate was condensed under nitrogen gas flow at 40 degrees C. The condensate was analyzed by Gas-Chromatography-Mass-Spectrum (GC-MS). Phenylethanol and phenylacetic acid were identified as major odor components. A mixture of authentic phenylacetic acid, its methyl and ethyl esters, smelled similar to the odor of cultivated medium of M. lepraemurium. Thus, phenylacetic acid was identified as the key odor component produced by M. lepraemurium. When initial isolation culture of M. lepraemurium from murine leproma was cultivated on the Ogawa yolk medium by adding phenylacetic acid, growth inhibition was brought by the compound.

  4. Yolk hormones influence in ovo chemosensory learning, growth, and feeding behavior in domestic chicks.

    PubMed

    Bertin, Aline; Meurisse, Maryse; Arnould, Cécile; Leterrier, Christine; Constantin, Paul; Cornilleau, Fabien; Vaudin, Pascal; Burlot, Thierry; Delaveau, Joel; Rat, Christophe; Calandreau, Ludovic

    2016-03-01

    In this study, we assessed whether prenatal exposure to elevated yolk steroid hormones can influence in ovo chemosensory learning and the behavior of domestic chicks. We simulated a maternal environmental challenge by experimentally enhancing yolk progesterone, testosterone, and estradiol concentrations in hen eggs prior to incubation. The embryos from these hormones-treated eggs (HO) as well as sham embryos (O) that had received the vehicle-only were exposed to the odor of fish oil (menhaden) between embryonic Days 11 and 20. An additional group of control embryos (C) was not exposed to the odor. All chicks were tested following hatching for their feeding preferences between foods that were or were not odorized with the menhaden odor. In the 3-min choice tests, the behavior of O chicks differed significantly according to the type of food whereas C and HO chicks showed no preference between odorized and non-odorized food. Our result suggests weaker response in HO chicks. In addition, HO chicks showed impaired growth and reduced intake of an unfamiliar food on the 24-h time scale compared to controls. Our data suggest that embryonic exposure to increased yolk hormone levels can alter growth, chemosensory learning, and the development of feeding behaviors. © 2015 Wiley Periodicals, Inc.

  5. Improving adjuvant systems for polyclonal egg yolk antibody (IgY) production in laying hens in terms of productivity and animal welfare.

    PubMed

    Marcq, Christopher; Marlier, Didier; Beckers, Yves

    2015-05-15

    The antibody production in the egg yolks of immunized laying hens is seen as a way of improving animal welfare compared with conventional production by mammals. Immunoglobulin Y (IgY) technology, however, has still to address welfare issues linked to the widespread use of an adjuvant in vaccines. Currently, Freund's adjuvants, complete (FCA) or incomplete (FIA), remain the standard. This study sought to evaluate various approaches used to enhance egg yolk antibody production in terms of both productivity and avian welfare. The outer membrane protein (OMP) of Salmonella Typhimurium was used as the prototype antigen. At 20 weeks of age, 56 ISA Brown hens, with specific-Salmonella-free status, were divided into seven groups (n=8) and received an initial intramuscular immunization. Hens in the two negative control groups received phosphate buffered saline (PBS) or FIA alone. Hens in the other groups received 80μg of Salmonella OMP emulsified with one of the following adjuvants: 200μl of FIA alone (T1); 200μl of FIA supplemented with 8μg of C-phosphate-guanosine oligodeoxynucleotides (CpG-ODN) (T2); and 280μl of Montanide ISA 70 VG (T4). Birds in the T3 group received the antigen in emulsion with FIA and were given the tested immunostimulatory component (l-carnitine) via their feed (100mg/kg). A positive control group (PC) received FCA for the first and final immunizations and FIA for the other boosters. Immunization was repeated after 20, 46, 82 and 221 days. Eggs were collected regularly until 242 days after the first immunization and the anti-Salmonella Typhimurium activities in the yolk were determined by ELISA. After 242 days, the birds were euthanized and the injection sites were evaluated for gross and microscopic lesions. Among the tested immunostimulatory approaches, supplementation of FIA with CpG-ODN led to a significant and long-lasting enhancement of the specific antibody response. This treatment was even higher than the positive benchmark using FCA in

  6. Analysis of Lethality and Malformations During Zebrafish (Danio rerio) Development.

    PubMed

    Raghunath, Azhwar; Perumal, Ekambaram

    2018-01-01

    The versatility offered by zebrafish (Danio rerio) makes it a powerful and an attractive vertebrate model in developmental toxicity and teratogenicity assays. Apart from the newly introduced chemicals as drugs, xenobiotics also induce abnormal developmental abnormalities and congenital malformations in living organisms. Over the recent decades, zebrafish embryo/larva has emerged as a potential tool to test teratogenicity potential of these chemicals. Zebrafish responds to compounds as mammals do as they share similarities in their development, metabolism, physiology, and signaling pathways with that of mammals. The methodology used by the different scientists varies enormously in the zebrafish embryotoxicity test. In this chapter, we present methods to assess lethality and malformations during zebrafish development. We propose two major malformations scoring systems: binomial and relative morphological scoring systems to assess the malformations in zebrafish embryos/larvae. Based on the scoring of the malformations, the test compound can be classified as a teratogen or a nonteratogen and its teratogenic potential is evaluated.

  7. Biosecurity and Health Monitoring at the Zebrafish International Resource Center

    PubMed Central

    Varga, Zoltán M.; Kent, Michael L.

    2016-01-01

    Abstract The Zebrafish International Resource Center (ZIRC) is a repository and distribution center for mutant, transgenic, and wild-type zebrafish. In recent years annual imports of new zebrafish lines to ZIRC have increased tremendously. In addition, after 15 years of research, we have identified some of the most virulent pathogens affecting zebrafish that should be avoided in large production facilities, such as ZIRC. Therefore, while importing a high volume of new lines we prioritize safeguarding the health of our in-house fish colony. Here, we describe the biosecurity and health-monitoring program implemented at ZIRC. This strategy was designed to prevent introduction of new zebrafish pathogens, minimize pathogens already present in the facility, and ensure a healthy zebrafish colony for in-house uses and shipment to customers. PMID:27031282

  8. Adhesion and growth inhibitory effect of chicken egg yolk antibody (IgY) on Salmonella enterica serovars Enteritidis and Typhimurium in vitro.

    PubMed

    Chalghoumi, Raja; Théwis, André; Beckers, Yves; Marcq, Christopher; Portetelle, Daniel; Schneider, Yves-Jacques

    2009-06-01

    The protective effects of powder preparation of egg yolk immunoglobulin Y (IgY), specific to Salmonella Enteritidis and Salmonella Typhimurium outer membrane proteins (OMP), against these two Salmonella sp. serovars were investigated in vitro in two different assays: adhesion-prevention and growth-inhibition. The adhesion-prevention assay was conducted using polarized monolayers of the human intestinal epithelial Caco-2 cell line. First, the conditions of Salmonella adherence to Caco-2 cells were optimized, and interferences of bacteria with the transepithelial electrical resistance (TER) of fully differentiated Caco-2 cell monolayers and the lactate dehydrogenase release upon exposure of the cells to Salmonella were evaluated. Both Salmonella sp. serovars were able to adhere to Caco-2 cells and decreased TER. Results from the adhesion-prevention assay demonstrated that specific IgY reduced the decrease in TER of the infected Caco-2 cell monolayers and blocked the Salmonella sp. adhesion in a concentration-dependent manner (p < 0.05). Nonspecific IgY also exhibited an inhibitory effect on these two parameters, but to a lesser extent than that of the specific IgY (p < 0.05). The protective effect of nonspecific IgY could be attributed to the low-density lipoprotein component of the water-soluble fraction of egg yolks that may not have been eliminated during ultrafiltration. The growth-inhibition assay revealed that specific IgY had an inhibitory effect on the bacterial growth, markedly during the late exponential phase, whereas nonspecific IgY failed to do so. Taken together, these results suggest that the in vitro growth inhibitory effect of specific IgY on Salmonella spp. resulted from the specific binding activity of these IgY to Salmonella sp. OMP. Passive immunization with Salmonella sp. OMP-specific IgY could thus be useful to prevent Salmonella colonization in broiler chickens and the subsequent carcass contamination during processing.

  9. A simple method for isolating chicken egg yolk immunoglobulin using effective delipidation solution and ammonium sulfate.

    PubMed

    Tong, Chenyao; Geng, Fang; He, Zhenjiao; Cai, Zhaoxia; Ma, Meihu

    2015-01-01

    Chicken egg yolk immunoglobulin (IgY) is a superior alternative to mammalian immunoglobulin. However, the practical application of IgY in research, diagnostics, and functional food is limited due to complex or time-consuming purification procedures. The objective of this study was to develop a simple, safe, large-scale separation method for IgY from egg yolk. Egg yolk was diluted with 6-fold delipidation solutions made of different types (pectin, λ-carrageenan, carboxymethylcellulose, methylcellulose, and dextran sulfate) and concentrations (0.01, 0.05, 0.1, 0.15, and 0.2%) of polysaccharides, respectively. The yolk solution was adjusted to pH 5.0, and then kept overnight at 4°C before being centrifuged at 4°C. The resulting supernatant was added to 35% (w/v) (NH4)2SO4 and then centrifuged. The precipitant, which contained IgY, was dissolved in distilled water and then dialyzed. SDS-PAGE and Western blotting were utilized to conduct qualitative analysis of IgY; high-performance liquid chromatography (HPLC) was used for quantitative analysis. The immunoreactivity of IgY was measured by ELISA. The results showed that yield, purity, and immunoreactivity varied with types and concentrations of polysaccharides. The optimal isolation of IgY for pectin, λ-carrageenan, dextran sulfate, and carboxymethylcellulose was at the concentration of 0.1%; for methylcellulose, optimal isolation was at 0.15%. The best results were obtained in the presence of 0.1% pectin. In this condition, yield and purity can reach 8.36 mg/mL egg yolk and 83.3%, respectively, and the negative effect of IgY on immunoreactivity can be minimized. The procedure of isolation was simplified to 2 steps with a higher yield of IgY, avoiding energy- and time-consuming methods. Therefore, the isolation condition under study has a great potential for food industry production of IgY on a large scale. © 2014 Poultry Science Association Inc.

  10. A morphological analysis of the transition between the embryonic primitive intestine and yolk sac in bovine embryos and fetuses.

    PubMed

    Mançanares, Celina A F; Leiser, Rudolf; Favaron, Phelipe O; Carvalho, Ana F; Oliveira, Vanessa C De; Santos, José M Dos; Ambrósio, Carlos E; Miglino, Maria A

    2013-07-01

    The yolk sac (YS) is the main source of embryonic nutrition during the period when the placenta has not yet formed. It is also responsible for hematopoiesis because the blood cells develop from it as part of the primitive embryonic circulation. The objective of this study was to characterize the transitional area between the YS and primitive gut using the techniques of light microscopy, transmission electron microscopy, and immunohistochemistry to detect populations of pluripotent cells by labeling with Oct4 antibody. In all investigated embryos, serial sections were made to permit the identification of this small, restricted area. We identified the YS connection with the primitive intestine and found that it is composed of many blood islands, which correspond to the vessels covered by vitelline and mesenchymal cells. We identified large numbers of hemangioblasts inside the vessels. The mesenchymal layer was thin and composed of elongated cells, and the vitelline endodermal membrane was composed of large, mono- or binucleated cells. The epithelium of the primitive intestine comprised stratified columnar cells and undifferentiated mesenchymal cells. The transitional area between the YS and the primitive intestine was very thin and composed of cells with irregular shapes, which formed a delicate lumen containing hemangioblasts. In the mesenchyme of the transitional area, there were a considerable number of small vessels containing hemangioblasts. Using Oct4 as a primary antibody, we identified positive cells in the metanephros, primordial gonad, and hepatic parenchyma as well as in YS cells, suggesting that these regions contain populations of pluripotent cells. Copyright © 2013 Wiley Periodicals, Inc.

  11. Biologically inspired robots elicit a robust fear response in zebrafish

    NASA Astrophysics Data System (ADS)

    Ladu, Fabrizio; Bartolini, Tiziana; Panitz, Sarah G.; Butail, Sachit; Macrı, Simone; Porfiri, Maurizio

    2015-03-01

    We investigate the behavioral response of zebrafish to three fear-evoking stimuli. In a binary choice test, zebrafish are exposed to a live allopatric predator, a biologically-inspired robot, and a computer-animated image of the live predator. A target tracking algorithm is developed to score zebrafish behavior. Unlike computer-animated images, the robotic and live predator elicit a robust avoidance response. Importantly, the robotic stimulus elicits more consistent inter-individual responses than the live predator. Results from this effort are expected to aid in hypothesis-driven studies on zebrafish fear response, by offering a valuable approach to maximize data-throughput and minimize animal subjects.

  12. Automatic multiple zebrafish larvae tracking in unconstrained microscopic video conditions.

    PubMed

    Wang, Xiaoying; Cheng, Eva; Burnett, Ian S; Huang, Yushi; Wlodkowic, Donald

    2017-12-14

    The accurate tracking of zebrafish larvae movement is fundamental to research in many biomedical, pharmaceutical, and behavioral science applications. However, the locomotive characteristics of zebrafish larvae are significantly different from adult zebrafish, where existing adult zebrafish tracking systems cannot reliably track zebrafish larvae. Further, the far smaller size differentiation between larvae and the container render the detection of water impurities inevitable, which further affects the tracking of zebrafish larvae or require very strict video imaging conditions that typically result in unreliable tracking results for realistic experimental conditions. This paper investigates the adaptation of advanced computer vision segmentation techniques and multiple object tracking algorithms to develop an accurate, efficient and reliable multiple zebrafish larvae tracking system. The proposed system has been tested on a set of single and multiple adult and larvae zebrafish videos in a wide variety of (complex) video conditions, including shadowing, labels, water bubbles and background artifacts. Compared with existing state-of-the-art and commercial multiple organism tracking systems, the proposed system improves the tracking accuracy by up to 31.57% in unconstrained video imaging conditions. To facilitate the evaluation on zebrafish segmentation and tracking research, a dataset with annotated ground truth is also presented. The software is also publicly accessible.

  13. Investigating How the Microbiome Interacts With Environmental Chemicals in Zebrafish

    EPA Pesticide Factsheets

    This internship will use an innovative experimental system comprised of colonized and microbe-free zebrafish to learn how microbial colonization status affects the toxicity of environmental chemicals.

  14. A Zebrafish Heart Failure Model for Assessing Therapeutic Agents.

    PubMed

    Zhu, Xiao-Yu; Wu, Si-Qi; Guo, Sheng-Ya; Yang, Hua; Xia, Bo; Li, Ping; Li, Chun-Qi

    2018-03-20

    Heart failure is a leading cause of death and the development of effective and safe therapeutic agents for heart failure has been proven challenging. In this study, taking advantage of larval zebrafish, we developed a zebrafish heart failure model for drug screening and efficacy assessment. Zebrafish at 2 dpf (days postfertilization) were treated with verapamil at a concentration of 200 μM for 30 min, which were determined as optimum conditions for model development. Tested drugs were administered into zebrafish either by direct soaking or circulation microinjection. After treatment, zebrafish were randomly selected and subjected to either visual observation and image acquisition or record videos under a Zebralab Blood Flow System. The therapeutic effects of drugs on zebrafish heart failure were quantified by calculating the efficiency of heart dilatation, venous congestion, cardiac output, and blood flow dynamics. All 8 human heart failure therapeutic drugs (LCZ696, digoxin, irbesartan, metoprolol, qiliqiangxin capsule, enalapril, shenmai injection, and hydrochlorothiazide) showed significant preventive and therapeutic effects on zebrafish heart failure (p < 0.05, p < 0.01, and p < 0.001) in the zebrafish model. The larval zebrafish heart failure model developed and validated in this study could be used for in vivo heart failure studies and for rapid screening and efficacy assessment of preventive and therapeutic drugs.

  15. Role of Pgrmc1 in estrogen maintenance of meiotic arrest in zebrafish oocytes through Gper/Egfr.

    PubMed

    Aizen, Joseph; Thomas, Peter

    2015-04-01

    The regulation of receptor trafficking to the cell surface and its effect on responses of target cells to growth factors and hormones remain poorly understood. Initial evidence has been recently obtained using cancer cells that surface expression of the epidermal growth factor receptor (EGFR) is dependent on its association with progesterone receptor membrane component 1 (PGRMC1). Estrogen inhibition of oocyte maturation (OM) in zebrafish is mediated through G-protein-coupled estrogen membrane receptor 1 (Gper1) and involves activation of Egfr. Therefore, in this study, the potential roles of Pgrmc1 in the cell surface expression and functions of Egfr in normal cells were investigated in this in vitro OM model of Egfr action using an inhibitor of PGMRC1 signaling, AG205. A single ∼60 kDa protein band, which corresponds to the size of the Pgrmc1 dimer, was detected on plasma membranes of fully grown oocytes by western blotting. Co-treatment with the PGRMC1 inhibitor AG205 (20 μM) blocked the inhibitory effects of 100 nM estradiol-17β and the GPER agonist, G-1, on spontaneous maturation of denuded zebrafish oocytes. Moreover, reversal of these estrogen effects on OM by the EGFR inhibitors AG1478 and AG825 (50 μM) was prevented by co-incubation with the PGRMC1 inhibitor. Inhibition of Pgrmc1 signaling with AG205 also caused a decrease in Egfr-dependent signaling and Egfr expression on oocyte cell membranes. These results indicate that maintenance of Pgrmc1 signaling is required for Egfr expression on zebrafish oocyte cell membranes and for conserving the functions of Egfr in maintaining meiotic arrest through estrogen activation of Gper. © 2015 Society for Endocrinology.

  16. Low-density Lipoprotein Improves Motility and Plasma Membrane Integrity of Cryopreserved Canine Epididymal Spermatozoa

    PubMed Central

    Prapaiwan, N.; Tharasanit, T.; Punjachaipornpol, S.; Yamtang, D.; Roongsitthichai, A.; Moonarmart, W.; Kaeoket, K.; Manee-in, S.

    2016-01-01

    Cryopreservation of caudal epididymal spermatozoa is an effective technique to conserve genetic potentials of superior dogs when it is not possible to collect ejaculated spermatozoa. Although hen egg yolk is commonly supplemented into the semen extender, active substances within the egg yolk which protect sperm against cryoinjury remain to be discovered. Among its compositions, low-density lipoprotein (LDL) has been reported to have a cryoprotective property for sperm cryopreservation. However, the effects of LDL on dog epididymal spermatozoa during cryopreservation have not yet been investigated. This study aimed to investigate the effects of LDL on epididymal spermatozoa quality following cryopreservation and thawing. After routine castration of 12 dogs, caudal epididymides from individuals were separated from the testes and cut into a few pieces in a Tris-buffer. Spermatozoa recovered from each sample were examined at once for sperm quality and divided into six groups of extender: no LDL, 20% egg yolk, 4%, 8%, 16%, and 24% LDL, before cryopreservation. The sperm aliquots were then equilibrated and conventionally frozen. After thawing, sperm motility, morphology, plasma membrane integrity, and acrosome integrity were evaluated. The results revealed that 4% LDL and 20% egg yolk yielded significantly higher sperm motility (57.69% and 52.69%, respectively, p<0.05) than other LDLs. In addition, 4% LDL yielded the significantly highest plasma membrane integrity (70.54%, p<0.05). In conclusion, the supplementation of 4% LDL in Tris-glucose extender could be applied for cryopreservation of canine epididymal spermatozoa. PMID:26954170

  17. Low-density Lipoprotein Improves Motility and Plasma Membrane Integrity of Cryopreserved Canine Epididymal Spermatozoa.

    PubMed

    Prapaiwan, N; Tharasanit, T; Punjachaipornpol, S; Yamtang, D; Roongsitthichai, A; Moonarmart, W; Kaeoket, K; Manee-In, S

    2016-05-01

    Cryopreservation of caudal epididymal spermatozoa is an effective technique to conserve genetic potentials of superior dogs when it is not possible to collect ejaculated spermatozoa. Although hen egg yolk is commonly supplemented into the semen extender, active substances within the egg yolk which protect sperm against cryoinjury remain to be discovered. Among its compositions, low-density lipoprotein (LDL) has been reported to have a cryoprotective property for sperm cryopreservation. However, the effects of LDL on dog epididymal spermatozoa during cryopreservation have not yet been investigated. This study aimed to investigate the effects of LDL on epididymal spermatozoa quality following cryopreservation and thawing. After routine castration of 12 dogs, caudal epididymides from individuals were separated from the testes and cut into a few pieces in a Tris-buffer. Spermatozoa recovered from each sample were examined at once for sperm quality and divided into six groups of extender: no LDL, 20% egg yolk, 4%, 8%, 16%, and 24% LDL, before cryopreservation. The sperm aliquots were then equilibrated and conventionally frozen. After thawing, sperm motility, morphology, plasma membrane integrity, and acrosome integrity were evaluated. The results revealed that 4% LDL and 20% egg yolk yielded significantly higher sperm motility (57.69% and 52.69%, respectively, p<0.05) than other LDLs. In addition, 4% LDL yielded the significantly highest plasma membrane integrity (70.54%, p<0.05). In conclusion, the supplementation of 4% LDL in Tris-glucose extender could be applied for cryopreservation of canine epididymal spermatozoa.

  18. Macrophage-expressed perforins mpeg1 and mpeg1.2 have an anti-bacterial function in zebrafish.

    PubMed

    Benard, Erica L; Racz, Peter I; Rougeot, Julien; Nezhinsky, Alexander E; Verbeek, Fons J; Spaink, Herman P; Meijer, Annemarie H

    2015-01-01

    Macrophage-expressed gene 1 (MPEG1) encodes an evolutionarily conserved protein with a predicted membrane attack complex/perforin domain associated with host defence against invading pathogens. In vertebrates, MPEG1/perforin-2 is an integral membrane protein of macrophages, suspected to be involved in the killing of intracellular bacteria by pore-forming activity. Zebrafish have 3 copies of MPEG1; 2 are expressed in macrophages, whereas the third could be a pseudogene. The mpeg1 and mpeg1.2 genes show differential regulation during infection of zebrafish embryos with the bacterial pathogens Mycobacterium marinum and Salmonella typhimurium. While mpeg1 is downregulated during infection with both pathogens, mpeg1.2 is infection inducible. Upregulation of mpeg1.2 is partially dependent on the presence of functional Mpeg1 and requires the Toll-like receptor adaptor molecule MyD88 and the transcription factor NFκB. Knockdown of mpeg1 alters the immune response to M. marinum infection and results in an increased bacterial burden. In Salmonella typhimurium infection, both mpeg1 and mpeg1.2 knockdown increase the bacterial burdens, but mpeg1 morphants show increased survival times. The combined results of these two in vivo infection models support the anti-bacterial function of the MPEG1/perforin-2 family and indicate that the intricate cross-regulation of the two mpeg1 copies aids the zebrafish host in combatting infection of various pathogens. © 2014 S. Karger AG, Basel.

  19. Specific binding of Clostridium perfringens enterotoxin fragment to Claudin-b and modulation of zebrafish epidermal barrier.

    PubMed

    Zhang, Jingjing; Ni, Chen; Yang, Zhenguo; Piontek, Anna; Chen, Huapu; Wang, Sijie; Fan, Yiming; Qin, Zhihai; Piontek, Joerg

    2015-08-01

    Claudins (Cldn) are the major components of tight junctions (TJs) sealing the paracellular cleft in tissue barriers of various organs. Zebrafish Cldnb, the homolog of mammalian Cldn4, is expressed at epithelial cell-cell contacts and is important for regulating epidermal permeability. The bacterial toxin Clostridium perfringens enterotoxin (CPE) has been shown to bind to a subset of mammalian Cldns. In this study, we used the Cldn-binding C-terminal domain of CPE (194-319 amino acids, cCPE 194-319 ) to investigate its functional role in modulating zebrafish larval epidermal barriers. In vitro analyses show that cCPE 194-319 removed Cldn4 from epithelial cells and disrupted the monolayer tightness, which could be rescued by the removal of cCPE 194-319. Incubation of zebrafish larvae with cCPE 194-319 removed Cldnb specifically from the epidermal cell membrane. Dye diffusion analysis with 4-kDa fluorescent dextran indicated that the permeability of the epidermal barrier increased due to cCPE 194-319 incubation. Electron microscopic investigation revealed reversible loss of TJ integrity by Cldnb removal. Collectively, these results suggest that cCPE 194-319 could be used as a Cldnb modulator to transiently open the epidermal barrier in zebrafish. In addition, zebrafish might be used as an in vivo system to investigate the capability of cCPE to enhance drug delivery across tissue barriers. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Promising Loci and Genes for Yolk and Ovary Weight in Chickens Revealed by a Genome-Wide Association Study.

    PubMed

    Sun, Congjiao; Lu, Jian; Yi, Guoqiang; Yuan, Jingwei; Duan, Zhongyi; Qu, Lujiang; Xu, Guiyun; Wang, Kehua; Yang, Ning

    2015-01-01

    Because it serves as the cytoplasm of the oocyte and provides a large amount of reserves, the egg yolk has biological significance for developing embryos. The ovary and its hierarchy of follicles are the main reproductive organs responsible for yolk deposition in chickens. However, the genetic architecture underlying the yolk and ovarian follicle weights remains elusive. Here, we measured the yolk weight (YW) at 11 age points from onset of egg laying to 72 weeks of age and measured the follicle weight (FW) and ovary weight (OW) at 73 weeks as part of a comprehensive genome-wide association study (GWAS) in 1,534 F2 hens derived from reciprocal crosses between White Leghorn (WL) and Dongxiang chickens (DX). For all ages, YWs exhibited moderate single nucleotide polymorphism (SNP)-based heritability estimates (0.25-0.38), while the estimates for FW (0.16) and OW (0.20) were relatively low. Independent univariate genome-wide screens for each trait identified 12, 3, and 31 novel significant associations with YW, FW, and OW, respectively. A list of candidate genes such as ZAR1, STARD13, ACER1b, ACSBG2, and DHRS12 were identified for having a plausible function in yolk and follicle development. These genes are important to the initiation of embryogenesis, lipid transport, lipoprotein synthesis, lipid droplet promotion, and steroid hormone metabolism, respectively. Our study provides for the first time a genome-wide association (GWA) analysis for follicle and ovary weight. Identification of the promising loci as well as potential candidate genes will greatly advance our understanding of the genetic basis underlying dynamic yolk weight and ovarian follicle development and has practical significance in breeding programs for the alteration of yolk weight at different age points.

  1. OECD validation study to assess intra- and inter-laboratory reproducibility of the zebrafish embryo toxicity test for acute aquatic toxicity testing.

    PubMed

    Busquet, François; Strecker, Ruben; Rawlings, Jane M; Belanger, Scott E; Braunbeck, Thomas; Carr, Gregory J; Cenijn, Peter; Fochtman, Przemyslaw; Gourmelon, Anne; Hübler, Nicole; Kleensang, André; Knöbel, Melanie; Kussatz, Carola; Legler, Juliette; Lillicrap, Adam; Martínez-Jerónimo, Fernando; Polleichtner, Christian; Rzodeczko, Helena; Salinas, Edward; Schneider, Katharina E; Scholz, Stefan; van den Brandhof, Evert-Jan; van der Ven, Leo T M; Walter-Rohde, Susanne; Weigt, Stefan; Witters, Hilda; Halder, Marlies

    2014-08-01

    The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were analytically confirmed for 11 chemicals. Newly fertilised zebrafish eggs (20/concentration and control) were exposed for 96h to chemicals. Four apical endpoints were recorded daily as indicators of acute lethality: coagulation of the embryo, lack of somite formation, non-detachment of the tail bud from the yolk sac and lack of heartbeat. Results (LC50 values for 48/96h exposure) show that the ZFET is a robust method with a good intra- and inter-laboratory reproducibility (CV<30%) for most chemicals and laboratories. The reproducibility was lower (CV>30%) for some very toxic or volatile chemicals, and chemicals tested close to their limit of solubility. The ZFET is now available as OECD Test Guideline 236. Considering the high predictive capacity of the ZFET demonstrated by Belanger et al. (2013) in their retrospective analysis of acute fish toxicity and fish embryo acute toxicity data, the ZFET is ready to be considered for acute fish toxicity for regulatory purposes. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Effects of Fab' fragments of specific egg yolk antibody (IgY-Fab') against Shewanella putrefaciens on the preservation of refrigerated turbot.

    PubMed

    Zhang, Qian; Lin, Hong; Sui, Jianxin; Wang, Jingxue; Cao, Limin

    2015-01-01

    In our previous studies the specific egg yolk antibody (IgY) against Shewanella putrefaciens (one of the specific spoilage organisms for marine products during aerobic chilling storage) demonstrated significant activity to prolong the shelf life of refrigerated fish. The exploitation of the antigen-binding fragment plus the hinge region (IgY-Fab') is now considered a promising method for improving the efficiency of such natural antimicrobial agents. The antimicrobial activity of IgY-Fab' against S. putrefaciens was investigated using refrigerated turbot as samples. By microbial, chemical and sensory tests, it was shown to be able to effectively inhibit bacterial growth and prolong the shelf life of samples, with an efficiency evaluated significantly higher than that of whole IgY with the same molarity. The interaction between IgY agents and S. putrefaciens cells was also investigated, and the IgY-Fab' showed a much greater ability to damage cell membranes than the whole IgY. Compared to whole IgY with the same molarity, IgY-Fab' demonstrated higher and more durable antimicrobial efficiency. Such a result was assumed to be closely related to its structural properties (such as the much lower molecular weight), which may enhance its ability to influence physiological activities of antigen bacteria, especially the property or/and structure of cell membranes. © 2014 Society of Chemical Industry.

  3. Deposition of carotenoids in egg yolk by short-term supplement of coloured carrot (Daucus carota) varieties as forage material for egg-laying hens.

    PubMed

    Hammershøj, Marianne; Kidmose, Ulla; Steenfeldt, Sanna

    2010-05-01

    Supplying egg-laying hens with different forage materials may influence egg production and quality. The aim of this study was to examine the short-term effects of standard feed plus 70 g day(-1) per hen of three coloured carrot varieties (orange, yellow and purple) as forage material in comparison with a standard feed control on egg production, egg yolk colour and deposition of carotenoids in the yolk. Carrot supplementation reduced feed intakes significantly, but not on a dry matter basis. Orange carrot treatment significantly reduced egg mass production, whereas yellow and purple carrot treatments did not differ from the control. Egg and yolk weights of all carrot-supplemented treatments were significantly lower than those of the control, but yolk percentages were similar. Yolk redness increased significantly in the order control < yellow < orange < purple. A similar trend was seen for yolk yellowness, but yellow and orange carrots reached the same level. Yolk colour and carotenoid contents correlated positively and significantly. In particular, purple carrot treatment increased the yolk content of lutein (>1.5-fold) and beta-carotene (>100-fold) compared with the control. Supplementing the feed of egg-laying hens with coloured carrots efficiently increased yolk colour parameters and carotenoid contents, which gives opportunities for improved nutritional value of eggs from forage material-supplemented hens.

  4. The nature of exocytosis in the yolk trophoblastic layer of silver arowana (Osteoglossum bicirrhosum) juvenile, the representative of ancient teleost fishes.

    PubMed

    Jaroszewska, Marta; Dabrowski, Konrad

    2009-11-01

    We have chosen the silver arowana (Osteoglossum bicirrhosum), a representative of the most ancient teleost family Osteoglossidae, to address the question of yolk nutrients utilization. Silver arowana have particularly large eggs (1-1.5 cm of diameter) and a unique morphology of the yolk. We present evidence that the yolk cytoplasmic zone (ycz) in the "yolksac juveniles" is a very complex structure involved in sequential processes of yolk hydrolysis, lipoprotein particles synthesis, their transport, and exocytosis. Vacuoles filled with yolk granules in different stages of digestion move from the vitellolysis zone through the ycz to be emptied into the microvillar interspace in the process of exocytosis. The area of the ycz with the abundance of the mitochondria must play an important role in providing energy for both the transport of vacuoles and the release of their contents. Therefore, we postulate that the function of yolk syncytial layer (ysl) as the "early embryonic patterning center" transforms in fish larvae or yolksac juveniles into a predominantly specialized role as the yolk trophoblastic layer (ytl) involved in yolk nutrients utilization. In addition to discovering the mechanism of transformation of the ysl function into ytl function, we suggest that the machinery involved in nutrient mobilization and exocytosis in yolk of arowana yolksac juveniles can be very attractive system for studies of regulatory processes in almost all secretory pathways in animal cells.

  5. The effect of polyunsaturated fatty acids on the homeostasis of yolk lipoprotein in C. elegans examined by CARS and two-photon excitation fluorescence (TPE-F) microscopy

    NASA Astrophysics Data System (ADS)

    Chen, Wei-Wen; Yi, Yung-Hsiang; Chien, Cheng-Hao; Hsiung, Kuei-Ching; Lin, Yi-Chun; Ma, Tian-Hsiang; Lo, Szecheng J.; Chang, Ta-Chau

    2016-03-01

    Yolk lipoprotein constitutes the major source of energy and the materials for synthesizing signaling factors for the development of oocytes and embryos in C. elegans. Polyunsaturated fatty acids (PUFAs) packed in yolk lipoprotein have been recently recognized as critical molecules for fertilization and reproduction.1 However, the relation between PUFAs and the homeostasis of yolk lipoprotein is not clear. Here we use coherent anti-Stokes Raman scattering (CARS) microscopy and two-photon excitation fluorescence (TPE-F) microscopy to examine the transportation of yolk lipoprotein. We demonstrate that CARS microscopy is a more sensitive method than the traditional Nile Red staining method in probing the abnormal accumulation of yolk lipoprotein in the body cavity of C. elegans. It is found that the accumulation of yolk lipoprotein is a time-dependent process. In addition, a negative correlation (r = -0.955) between reproductive aging and abnormal accumulation of yolk lipoprotein is established. We further examine wild-type, fat-1, and fat-2 worms with or without the expression of GFP-tagged yolk lipoprotein (VIT-2-GFP). Our data reveal that PUFAs have a positive effect on the synthesis and endocytosis of yolk lipoprotein, confirming the model proposed by Edmonds et al.2

  6. Membranous nephropathy

    MedlinePlus

    ... glomerulonephritis; Membranous GN; Extramembranous glomerulonephritis; Glomerulonephritis - membranous; MGN Images Kidney anatomy References Appel GB, Radhakrishnan J. Glomerular disorders and nephrotic syndromes. In: Goldman L, ...

  7. The Morphogenesis of Cranial Sutures in Zebrafish

    PubMed Central

    Topczewska, Jolanta M.; Shoela, Ramy A.; Tomaszewski, Joanna P.; Mirmira, Rupa B.; Gosain, Arun K.

    2016-01-01

    Using morphological, histological, and TEM analyses of the cranium, we provide a detailed description of bone and suture growth in zebrafish. Based on expression patterns and localization, we identified osteoblasts at different degrees of maturation. Our data confirm that, unlike in humans, zebrafish cranial sutures maintain lifelong patency to sustain skull growth. The cranial vault develops in a coordinated manner resulting in a structure that protects the brain. The zebrafish cranial roof parallels that of higher vertebrates and contains five major bones: one pair of frontal bones, one pair of parietal bones, and the supraoccipital bone. Parietal and frontal bones are formed by intramembranous ossification within a layer of mesenchyme positioned between the dermal mesenchyme and meninges surrounding the brain. The supraoccipital bone has an endochondral origin. Cranial bones are separated by connective tissue with a distinctive architecture of osteogenic cells and collagen fibrils. Here we show RNA in situ hybridization for col1a1a, col2a1a, col10a1, bglap/osteocalcin, fgfr1a, fgfr1b, fgfr2, fgfr3, foxq1, twist2, twist3, runx2a, runx2b, sp7/osterix, and spp1/ osteopontin, indicating that the expression of genes involved in suture development in mammals is preserved in zebrafish. We also present methods for examining the cranium and its sutures, which permit the study of the mechanisms involved in suture patency as well as their pathological obliteration. The model we develop has implications for the study of human disorders, including craniosynostosis, which affects 1 in 2,500 live births. PMID:27829009

  8. Ethanol Exposure Causes Muscle Degeneration in Zebrafish

    PubMed Central

    Coffey, Elizabeth C.; Pasquarella, Maggie E.; Goody, Michelle F.

    2018-01-01

    Alcoholic myopathies are characterized by neuromusculoskeletal symptoms such as compromised movement and weakness. Although these symptoms have been attributed to neurological damage, EtOH may also target skeletal muscle. EtOH exposure during zebrafish primary muscle development or adulthood results in smaller muscle fibers. However, the effects of EtOH exposure on skeletal muscle during the growth period that follows primary muscle development are not well understood. We determined the effects of EtOH exposure on muscle during this phase of development. Strikingly, muscle fibers at this stage are acutely sensitive to EtOH treatment: EtOH induces muscle degeneration. The severity of EtOH-induced muscle damage varies but muscle becomes more refractory to EtOH as muscle develops. NF-kB induction in muscle indicates that EtOH triggers a pro-inflammatory response. EtOH-induced muscle damage is p53-independent. Uptake of Evans blue dye shows that EtOH treatment causes sarcolemmal instability before muscle fiber detachment. Dystrophin-null sapje mutant zebrafish also exhibit sarcolemmal instability. We tested whether Trichostatin A (TSA), which reduces muscle degeneration in sapje mutants, would affect EtOH-treated zebrafish. We found that TSA and EtOH are a lethal combination. EtOH does, however, exacerbate muscle degeneration in sapje mutants. EtOH also disrupts adhesion of muscle fibers to their extracellular matrix at the myotendinous junction: some detached muscle fibers retain beta-Dystroglycan indicating failure of muscle end attachments. Overexpression of Paxillin, which reduces muscle degeneration in zebrafish deficient for beta-Dystroglycan, is not sufficient to rescue degeneration. Taken together, our results suggest that EtOH exposure has pleiotropic deleterious effects on skeletal muscle. PMID:29615556

  9. Expression of Glycosaminoglycan Epitopes During Zebrafish Skeletogenesis

    PubMed Central

    Hayes, Anthony J; Mitchell, Ruth E; Bashford, Andrew; Reynolds, Scott; Caterson, Bruce; Hammond, Chrissy L

    2013-01-01

    Background: The zebrafish is an important developmental model. Surprisingly, there are few studies that describe the glycosaminoglycan composition of its extracellular matrix during skeletogenesis. Glycosaminoglycans on proteoglycans contribute to the material properties of musculo skeletal connective tissues, and are important in regulating signalling events during morphogenesis. Sulfation motifs within the chain structure of glycosaminoglycans on cell-associated and extracellular matrix proteoglycans allow them to bind and regulate the sequestration/presentation of bioactive signalling molecules important in musculo-skeletal development. Results: We describe the spatio-temporal expression of different glycosaminoglycan moieties during zebrafish skeletogenesis with antibodies recognising (1) native sulfation motifs within chondroitin and keratan sulfate chains, and (2) enzyme-generated neoepitope sequences within the chain structure of chondroitin sulfate (i.e., 0-, 4-, and 6-sulfated isoforms) and heparan sulfate glycosaminoglycans. We show that all the glycosaminoglycan moieties investigated are expressed within the developing skeletal tissues of larval zebrafish. However, subtle changes in their patterns of spatio-temporal expression over the period examined suggest that their expression is tightly and dynamically controlled during development. Conclusions: The subtle differences observed in the domains of expression between different glycosaminoglycan moieties suggest differences in their functional roles during establishment of the primitive analogues of the skeleton. Developmental Dynamics 242:778–789, 2013. © 2013 Wiley Periodicals, Inc. Key Findings The developing zebrafish skeleton expresses many different glycosaminoglycan modifications. Multiple different glycosaminoglycan epitopes are dynamically expressed in the craniofacial skeleton. Expression of chondroitin sulfate moieties are dynamically expressed in the vertebral column and precede

  10. BDE 49 and developmental toxicity in zebrafish

    PubMed Central

    McClain, Valerie; Stapleton, Heather M.; Gallagher, Evan

    2011-01-01

    The polybrominated diphenyl ethers (PBDEs) are a group of brominated flame retardants. Human health concerns of these agents have largely centered upon their potential to elicit reproductive and developmental effects. Of the various congeners, BDE 49 (2,2’,4,5’-tetrabromodiphenyl ether) has been poorly studied, despite the fact that it is often detected in the tissues of fish and wildlife species. Furthermore, we have previously shown that BDE 49 is a metabolic debromination product of BDE 99 hepatic metabolism in salmon, carp and trout, underscoring the need for a better understanding of biological effects. In the current study, we investigated the developmental toxicity of BDE 49 using the zebrafish (Danio rerio) embryo larval model. Embryo and larval zebrafish were exposed to BDE 49 at either 5 hours post fertilization (hpf) or 24 hpf and monitored for developmental and neurotoxicity. Exposure to BDE 49 at concentrations of 4 µM- 32 µM caused a dose-dependent loss in survivorship at 6 days post fertilization (dpf). Morphological impairments were observed prior to the onset of mortality, the most striking of which included severe dorsal curvatures of the tail. The incidence of dorsal tail curvatures was dose and time dependent. Exposure to BDE 49 caused cardiac toxicity as evidenced by a significant reduction in zebrafish heart rates at 6 dpf but not earlier, suggesting that cardiac toxicity was non-specific and associated with physiological stress. Neurobehavioral injury from BDE 49 was evidenced by an impairment of touch-escape responses observed at 5 dpf. Our results indicate that BDE 49 is a developmental toxicant in larval zebrafish that can cause morphological abnormalities and adversely affect neurobehavior. The observed toxicities from BDE 49 were similar in scope to those previously reported for the more common tetrabrominated congener, BDE 47, and also for other lower brominated PBDEs, suggest that these compounds may share similarities in risk to

  11. Social dominance modulates eavesdropping in zebrafish

    PubMed Central

    Abril-de-Abreu, Rodrigo; Cruz, Ana S.; Oliveira, Rui F.

    2015-01-01

    Group living animals may eavesdrop on signalling interactions between conspecifics and integrate it with their own past social experience in order to optimize the use of relevant information from others. However, little is known about this interplay between public (eavesdropped) and private social information. To investigate it, we first manipulated the dominance status of bystander zebrafish. Next, we either allowed or prevented bystanders from observing a fight. Finally, we assessed their behaviour towards the winners and losers of the interaction, using a custom-made video-tracking system and directional analysis. We found that only dominant bystanders who had seen the fight revealed a significant increase in directional focus (a measure of attention) towards the losers of the fights. Furthermore, our results indicate that information about the fighters' acquired status was collected from the signalling interaction itself and not from post-interaction status cues, which implies the existence of individual recognition in zebrafish. Thus, we show for the first time that zebrafish, a highly social model organism, eavesdrop on conspecific agonistic interactions and that this process is modulated by the eavesdroppers' dominance status. We suggest that this type of integration of public and private information may be ubiquitous in social learning processes. PMID:26361550

  12. Use of zebrafish to study Shigella infection

    PubMed Central

    Duggan, Gina M.

    2018-01-01

    ABSTRACT Shigella is a leading cause of dysentery worldwide, responsible for up to 165 million cases of shigellosis each year. Shigella is also recognised as an exceptional model pathogen to study key issues in cell biology and innate immunity. Several infection models have been useful to explore Shigella biology; however, we still lack information regarding the events taking place during the Shigella infection process in vivo. Here, we discuss a selection of mechanistic insights recently gained from studying Shigella infection of zebrafish (Danio rerio), with a focus on cytoskeleton rearrangements and cellular immunity. We also discuss how infection of zebrafish can be used to investigate new concepts underlying infection control, including emergency granulopoiesis and the use of predatory bacteria to combat antimicrobial resistance. Collectively, these insights illustrate how Shigella infection of zebrafish can provide fundamental advances in our understanding of bacterial pathogenesis and vertebrate host defence. This information should also provide vital clues for the discovery of new therapeutic strategies against infectious disease in humans. PMID:29590642

  13. Cell Migration During Heart Regeneration in Zebrafish

    PubMed Central

    Tahara, Naoyuki; Brush, Michael; Kawakami, Yasuhiko

    2018-01-01

    Zebrafish possess the remarkable ability to regenerate injured hearts as adults, which contrasts the very limited ability in mammals. Although very limited, mammalian hearts do in fact have measurable levels of cardiomyocyte regeneration. Therefore, elucidating mechanisms of zebrafish heart regeneration would provide information of naturally occurring regeneration to potentially apply to mammalian studies, in addition to addressing this biologically interesting phenomenon in itself. Studies over the past 13 years have identified processes and mechanisms of heart regeneration in zebrafish. After heart injury, preexisting cardiomyocytes dedifferentiate, enter the cell cycle, and repair the injured myocardium. This process requires interaction with epicardial cells, endocardial cells, and vascular endothelial cells. Epicardial cells envelope the heart, while endocardial cells make up the inner lining of the heart. They provide paracrine signals to cardiomyocytes to regenerate the injured myocardium, which is vascularized during heart regeneration. In addition, accumulating results suggest that local migration of these major cardiac cell types have roles in heart regeneration. In this review, we summarize the characteristics of various heart injury methods used in the research community and regeneration of the major cardiac cell types. Then, we discuss local migration of these cardiac cell types and immune cells during heart regeneration. PMID:27085002

  14. Cell migration during heart regeneration in zebrafish.

    PubMed

    Tahara, Naoyuki; Brush, Michael; Kawakami, Yasuhiko

    2016-07-01

    Zebrafish possess the remarkable ability to regenerate injured hearts as adults, which contrasts the very limited ability in mammals. Although very limited, mammalian hearts do in fact have measurable levels of cardiomyocyte regeneration. Therefore, elucidating mechanisms of zebrafish heart regeneration would provide information of naturally occurring regeneration to potentially apply to mammalian studies, in addition to addressing this biologically interesting phenomenon in itself. Studies over the past 13 years have identified processes and mechanisms of heart regeneration in zebrafish. After heart injury, pre-existing cardiomyocytes dedifferentiate, enter the cell cycle, and repair the injured myocardium. This process requires interaction with epicardial cells, endocardial cells, and vascular endothelial cells. Epicardial cells envelope the heart, while endocardial cells make up the inner lining of the heart. They provide paracrine signals to cardiomyocytes to regenerate the injured myocardium, which is vascularized during heart regeneration. In addition, accumulating results suggest that local migration of these major cardiac cell types have roles in heart regeneration. In this review, we summarize the characteristics of various heart injury methods used in the research community and regeneration of the major cardiac cell types. Then, we discuss local migration of these cardiac cell types and immune cells during heart regeneration. Developmental Dynamics 245:774-787, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Zebrafish heart regeneration: 15 years of discoveries

    PubMed Central

    González‐Rosa, Juan Manuel; Burns, Caroline E.

    2017-01-01

    Abstract Cardiovascular disease is the leading cause of death worldwide. Compared to other organs such as the liver, the adult human heart lacks the capacity to regenerate on a macroscopic scale after injury. As a result, myocardial infarctions are responsible for approximately half of all cardiovascular related deaths. In contrast, the zebrafish heart regenerates efficiently upon injury through robust myocardial proliferation. Therefore, deciphering the mechanisms that underlie the zebrafish heart's endogenous regenerative capacity represents an exciting avenue to identify novel therapeutic strategies for inducing regeneration of the human heart. This review provides a historical overview of adult zebrafish heart regeneration. We summarize 15 years of research, with a special focus on recent developments from this fascinating field. We discuss experimental findings that address fundamental questions of regeneration research. What is the origin of regenerated muscle? How is regeneration controlled from a genetic and molecular perspective? How do different cell types interact to achieve organ regeneration? Understanding natural models of heart regeneration will bring us closer to answering the ultimate question: how can we stimulate myocardial regeneration in humans? PMID:28979788

  16. Disease modeling in genetic kidney diseases: zebrafish.

    PubMed

    Schenk, Heiko; Müller-Deile, Janina; Kinast, Mark; Schiffer, Mario

    2017-07-01

    Growing numbers of translational genomics studies are based on the highly efficient and versatile zebrafish (Danio rerio) vertebrate model. The increasing types of zebrafish models have improved our understanding of inherited kidney diseases, since they not only display pathophysiological changes but also give us the opportunity to develop and test novel treatment options in a high-throughput manner. New paradigms in inherited kidney diseases have been developed on the basis of the distinct genome conservation of approximately 70 % between zebrafish and humans in terms of existing gene orthologs. Several options are available to determine the functional role of a specific gene or gene sets. Permanent genome editing can be induced via complete gene knockout by using the CRISPR/Cas-system, among others, or via transient modification by using various morpholino techniques. Cross-species rescues succeeding knockdown techniques are employed to determine the functional significance of a target gene or a specific mutation. This article summarizes the current techniques and discusses their perspectives.

  17. Effect of PMA-induced protein kinase C activation on development and apoptosis in early zebrafish embryos.

    PubMed

    Hrubik, Jelena; Glisic, Branka; Samardzija, Dragana; Stanic, Bojana; Pogrmic-Majkic, Kristina; Fa, Svetlana; Andric, Nebojsa

    2016-12-01

    Protein kinase C (PKC) isoforms have been implicated in several key steps during early development, but the consequences of xenobiotic-induced PKC activation during early embryogenesis are still unknown. In this study, zebrafish embryos were exposed to a range of phorbol 12-myristate 13-acetate (PMA) concentrations (0-200μg/L) at different time points after fertilization. Results showed that 200μgPMA/L caused development of yolk bags, cardiac edema, slow blood flow, pulsating blood flow, slow pulse, elongated heart, lack of tail fins, curved tail, and coagulation. PMA exposure decreased survival rate of the embryos starting within the first 24h and becoming more pronounced after prolonged exposure (96h). PMA increased the number of apoptotic cells in the brain region as demonstrated by acridine orange staining and caused up-regulation of caspase 9 (casp9) and p53 up-regulated modulator of apoptosis (puma) mRNA in whole embryos. PMA caused oxidative stress in the embryos as demonstrated by decreased mRNA expression of catalase and superoxide dismutase 2. Inhibition of Pkc with GF109203X improved overall survival rate, reduced apoptosis in the brain and decreased expression of casp9 and puma in the PMA-exposed embryos. However, Pkc inhibition neither prevented development of deformities nor reversed oxidative stress in the PMA-exposed embryos. These data suggest that direct over-activation of Pkc during early embryogenesis of zebrafish is associated with apoptosis and decreased survival rate of the embryos. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. An approach to clarify the effect mechanism of glyphosate on body malformations during embryonic development of zebrafish (Daino rerio).

    PubMed

    Sulukan, Ekrem; Köktürk, Mine; Ceylan, Hamid; Beydemir, Şükrü; Işik, Mesut; Atamanalp, Muhammed; Ceyhun, Saltuk Buğrahan

    2017-08-01

    In this study, it has been investigated that the effects of glyphosate, which is a herbicide within organophosphate and unselective widely used in agriculture on enzyme activity of carbonic anhydrase, production of reactive oxygen species, cell apoptosis and body morphology during the embryonic development of zebrafish. To this end, it has been treated embryo with 1, 5, 10 and 100 mg/L gyphosate at 96 h. The embryos treated with glyphosate from 4 hpf were evaluated by considering the survival rates, hatching rates, body malformations under the stereo microscope in 24, 48, 72 and 96th hours. In order to clarify the mechanism of the abnormalities ROS, enzyme activity of carbonic anhydrase and cellular death were detected end of the 96th hour. The data obtained in the present study have shown that glyphosate treatment inhibited CA activity, caused production of ROS especially branchial regions, triggered cellular apoptosis and caused several types of malformations including pericardial edema, yolk sac edema, spinal curvature and body malformation in a dose-dependent manner. As a conclusion, in light of present and previous studies, we can deduce that (1) the probable reason of ROS production was CA inhibition via decreasing of CO 2 extraction and developing respiratory acidosis (however, one needs to clarify), (2) abundance of ROS triggered cellular apoptosis and (3) as a result of cellular apoptosis malformations increased. These data will enable us to further understand potential toxic mechanism of glyphosate on embryonic development stage of zebrafish and may be useful for assessment in the toxicology studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Toxicity of effluents from gasoline stations oil-water separators to early life stages of zebrafish Danio rerio.

    PubMed

    Alves, Romulo Nepomuceno; Mariz, Célio Freire; Paulo, Driele Ventura de; Carvalho, Paulo S M

    2017-07-01

    Used petroleum hydrocarbons and gasoline stations runoff are significant sources of polycyclic aromatic hydrocarbons (PAHs) to aquatic ecosystems. Samples of the final effluent of oil-water-separators were collected at gasoline stations in the metropolitan region of Recife, Brazil, before release to sewage or rainwater systems. Effluent soluble fractions (ESF) were prepared and bioassays were performed according to the Fish Embryo Toxicity Test. The test involved exposing zebrafish Danio rerio embryos to dilutions of the ESFs for 96 h, with daily examination of lethality and sublethal morphological effects integrated through the General Morphology Score (GMS), based on the achievement of developmental hallmarks. Frequencies of abnormalities were recorded after exposures. ESF LC50-96h (lethal concentration to 50% of exposed embryos) in the most toxic effluent achieved 8.9% (v/v), equivalent to 11 μg phenanthrene equivalents L -1 . GMS scores indicated significantly delayed embryo-larval development at ESF dilutions of 10% and 20% from effluents of all gas stations. Major abnormalities detected after the 96 h exposure included the presence of a yolk sac not fully absorbed coupled with the lack of an inflated swim bladder, lack of both pectoral fins, and the failure to develop a protruding mouth. Effective equivalent PAH concentrations that induce a 50% frequency of larvae without an inflated swim bladder (EC50) were 4.9 μg phenanthrene L -1 , 21.8 μg naphthalene L -1 , and 34.1 μg chrysene L -1 . This study shows that PAHs in ESFs from gas stations oil water separators are toxic to zebrafish, contributing to the toxicity of urban storm waters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. The potency of chicken egg yolk immunoglobulin (IgY) specific as immunotherapy to Mycobacterium tuberculosis infection

    PubMed Central

    Sudjarwo, Sri Agus; Eraiko, Koerniasari; Sudjarwo, Giftania Wardani; Koerniasari

    2017-01-01

    The aim of this study was to characterize of chicken egg yolk immunoglobulins (IgYs) specific as immunotherapy to Mycobacterium tuberculosis complex (MTBC) infection. Lohmann laying hens were immunized intramuscularly with antigenic of MTBC. Egg yolk was separated from egg white, and IgY antibody was then purified by multiple polyethylene glycols 6000 extraction and ammonium sulfate purification steps. The IgY anti-MTBC concentration in egg yolk increased at 2 weeks and it reached a maximum at 4 weeks after immunization. After 6 weeks, the levels of IgY anti-MTBC decreased gradually. The antibody of MTBC was detected and produces a specific line of precipitation in agar gel precipitation test beginning the week 2 after the first immunization. Analysis of results obtained with ELISA showed a significant increase in the MTBC specific antibodies after 2 weeks and reached a plateau at 4 weeks from the booster immunization. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the IgY preparation to be pure and dissociated into protein bands with molecular weights of 112, 78, 69, 49, and 28 kDa and Western blot analysis shown the presence of anti-MTBC IgY in egg yolks, with molecular weights of approximately 78 kDa. These results suggested that egg yolk could be a practical strategy in large-scale production of specific anti-MTBC IgY for immunotherapy of TBC. PMID:28795022

  1. The potency of chicken egg yolk immunoglobulin (IgY) specific as immunotherapy to Mycobacterium tuberculosis infection.

    PubMed

    Sudjarwo, Sri Agus; Eraiko, Koerniasari; Sudjarwo, Giftania Wardani; Koerniasari

    2017-01-01

    The aim of this study was to characterize of chicken egg yolk immunoglobulins (IgYs) specific as immunotherapy to Mycobacterium tuberculosis complex (MTBC) infection. Lohmann laying hens were immunized intramuscularly with antigenic of MTBC. Egg yolk was separated from egg white, and IgY antibody was then purified by multiple polyethylene glycols 6000 extraction and ammonium sulfate purification steps. The IgY anti-MTBC concentration in egg yolk increased at 2 weeks and it reached a maximum at 4 weeks after immunization. After 6 weeks, the levels of IgY anti-MTBC decreased gradually. The antibody of MTBC was detected and produces a specific line of precipitation in agar gel precipitation test beginning the week 2 after the first immunization. Analysis of results obtained with ELISA showed a significant increase in the MTBC specific antibodies after 2 weeks and reached a plateau at 4 weeks from the booster immunization. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the IgY preparation to be pure and dissociated into protein bands with molecular weights of 112, 78, 69, 49, and 28 kDa and Western blot analysis shown the presence of anti-MTBC IgY in egg yolks, with molecular weights of approximately 78 kDa. These results suggested that egg yolk could be a practical strategy in large-scale production of specific anti-MTBC IgY for immunotherapy of TBC.

  2. Liposome encapsulated soy lecithin and cholesterol can efficiently replace chicken egg yolk in human semen cryopreservation medium.

    PubMed

    Mutalik, Srinivas; Salian, Sujith Raj; Avadhani, Kiran; Menon, Jyothsna; Joshi, Haritima; Hegde, Aswathi Raju; Kumar, Pratap; Kalthur, Guruprasad; Adiga, Satish Kumar

    2014-06-01

    Cryopreservation of spermatozoa plays a significant role in reproductive medicine and fertility preservation. Chicken egg yolk is used as an extender in cryopreservation of human spermatozoa using glycerol egg yolk citrate (GEYC) buffered medium. Even though 50% survival of spermatozoa is generally achieved with this method, the risk of high levels of endotoxins and transmission pathogens from chicken egg yolk is a matter of concern. In the present study we attempted to establish a chemically defined cryopreservation medium which can replace the chicken egg yolk without affecting sperm survival. Ejaculates from 28 men were cryopreserved with GEYC based freezing medium or liposome encapsulated soy lecithin-cholesterol based freezing medium (LFM). The semen samples were subjected to rapid thawing after 14 days of storage in liquid nitrogen. Post-thaw analysis indicated significantly higher post-thaw motility and sperm survival in spermatozoa cryopreserved with LFM compared to conventional GEYC freezing medium. The soy lecithin and cholesterol at the ratio of 80:20 with sucrose showed the highest percentage of post-thaw motility and survival compared to the other compositions. In conclusion, chemically defined cryopreservation medium with liposome encapsulated soy lecithin and cholesterol can effectively replace the chicken egg yolk from human semen cryopreservation medium without compromising post-thaw outcome.

  3. Multi-shelled ZnCo2O4 yolk-shell spheres for high-performance acetone gas sensor

    NASA Astrophysics Data System (ADS)

    Xiong, Ya; Zhu, Zongye; Ding, Degong; Lu, Wenbo; Xue, Qingzhong

    2018-06-01

    In the present study, multi-shelled ZnCo2O4 yolk-shell spheres have been successfully prepared by using carbonaceous microspheres as templates. It is found that the multi-shelled ZnCo2O4 yolk-shell spheres based sensor shows optimal sensing performances (response value of 38.2, response/recovery time of 19 s/71 s) toward 500 ppm acetone at 200 °C. In addition, this sensor exhibits a low detection limit of 0.5 ppm acetone (response value of 1.36) and a good selectivity toward hydrogen, methane, ethanol, ammonia and carbon dioxide. Furthermore, it is demonstrated that acetone gas response of multi-shelled ZnCo2O4 yolk-shell spheres is significantly better than that of ZnCo2O4 nanotubes and ZnCo2O4 nanosheets. High acetone response of the multi-shelled ZnCo2O4 yolk-shell spheres is attributed to the enhanced gas accessibility of the multi-shell morphology caused by the small crystalline size and high specific surface area while the short response/recovery time is mainly related to the rapid gas diffusion determined by the highly porous structure. Our work puts forward an exciting opportunity in designing various yolk-shelled structures for multipurpose applications.

  4. Sex-biased investment in yolk androgens depends on female quality and laying order in zebra finches (Taeniopygia guttata)

    NASA Astrophysics Data System (ADS)

    Gilbert, Lucy; Rutstein, Alison N.; Hazon, Neil; Graves, Jefferson A.

    2005-04-01

    The Trivers-Willard hypothesis predicts sex biases in parental investment according to parental condition. In addition, parents may need to sex bias their investment if there is an asymmetry between the sexes in offspring fitness under different conditions. For studying maternal differential investment, egg resources are ideal subjects because they are self contained and allocated unequivocally by the female. Recent studies show that yolk androgens can be beneficial to offspring, so here we test for sex-biased investment with maternal investment of yolk testosterone (T) in zebra finch (Taeniopygia guttata) eggs. From the Trivers-Willard hypothesis, we predicted females to invest more in male eggs in optimum circumstances (e.g. good-condition mother, early-laid egg), and more in female eggs under suboptimal conditions (e.g. poor-condition mother, late-laid egg). This latter prediction is also because in this species there is a female nestling disadvantage in poor conditions and we expected mothers to help compensate for this in female eggs. Indeed, we found more yolk T in female than male eggs. Moreover, in accordance with our predictions, yolk T in male eggs increased with maternal quality relative to female eggs, and decreased with laying order relative to female eggs. This supports our predictions for the different needs and value of male and female offspring in zebra finches. Our results support the idea that females may use yolk androgens as a tool to adaptively manipulate the inequalities between different nestlings.

  5. Biofortified orange maize enhances β-cryptoxanthin concentrations in egg yolks of laying hens better than tangerine peel fortificant.

    PubMed

    Heying, Emily K; Tanumihardjo, Jacob P; Vasic, Vedran; Cook, Mark; Palacios-Rojas, Natalia; Tanumihardjo, Sherry A

    2014-12-10

    The xanthophyll β-cryptoxanthin provides vitamin A and has other purported health benefits. Laying hens deposit xanthophyll carotenoids into egg yolk. Hens (n = 8/group) were fed conventional-bred high β-cryptoxanthin biofortified (orange) maize, tangerine peel-fortified white maize, lutein-fortified yellow maize, or white maize for 40 d to investigate yolk color changes using L*a*b* scales, yolk carotenoid enhancement, and hen vitamin A status. Yolks from hens fed orange maize had scores indicating a darker, orange color and mean higher β-cryptoxanthin, zeaxanthin, and β-carotene concentrations (8.43 ± 1.82, 23.1 ± 4.8, 0.16 ± 0.08 nmol/g, respectively) than other treatments (P < 0.0001). Yolk retinol concentrations (mean: 14.4 ± 3.42 nmol/g) were similar among groups and decreased with time (P < 0.0001). Hens fed orange maize had higher liver retinol (0.53 ± 0.20 μmol/g liver) than other groups (P < 0.0001). β-Cryptoxanthin-biofortified eggs could be another choice for consumers, providing enhanced color through a provitamin A carotenoid and supporting eggs' status as a functional food.

  6. Au@TiO2 yolk-shell nanostructures for enhanced performance in both photoelectric and photocatalytic solar conversion

    NASA Astrophysics Data System (ADS)

    He, Qinrong; Sun, Hang; Shang, Yinxing; Tang, Yanan; She, Ping; Zeng, Shan; Xu, Kongliang; Lu, Guolong; Liang, Song; Yin, Shengyan; Liu, Zhenning

    2018-05-01

    Solar energy conversion is an important field gaining increasing interest. Herein, bio-inspired Au@TiO2 yolk-shell nanoparticles (NPs) have been prepared via a facial one-pot hydrothermal approach. The Au@TiO2 yolk-shell NPs can self-assemble into 3D-structure to form photoelectrode for photoelectric conversion. The obtained photoelectrode demonstrates a swift and stable photocurrent of 3.5 μA/cm2, which is 4.2 and 1.6 times higher than those of the photocurrents generated by the counterparts of commercial TiO2 and Au@TiO2 core-shell NPs, respectively. Moreover, compared to the commercial TiO2 and Au@TiO2 core-shell NPs, the Au@TiO2 yolk-shell NPs also exhibit superior photocatalytic activity, delivering a H2 evolution rate of 4.92 mmol/g h. The performance improvement observed for the Au@TiO2 yolk-shell NPs is likely contributed by two synergistic factors, i.e. the incorporation of AuNPs and the unique hollow structure, which benefit the activity by simultaneously enhancing light utilization, charge separation and reaction site accessibility. The rational design and fabrication of Au@TiO2 yolk-shell NPs hold great promise for future application in efficient solar energy conversion.

  7. Smooth muscle tension induces invasive remodeling of the zebrafish intestine.

    PubMed

    Seiler, Christoph; Davuluri, Gangarao; Abrams, Joshua; Byfield, Fitzroy J; Janmey, Paul A; Pack, Michael

    2012-01-01

    The signals that initiate cell invasion are not well understood, but there is increasing evidence that extracellular physical signals play an important role. Here we show that epithelial cell invasion in the intestine of zebrafish meltdown (mlt) mutants arises in response to unregulated contractile tone in the surrounding smooth muscle cell layer. Physical signaling in mlt drives formation of membrane protrusions within the epithelium that resemble invadopodia, matrix-degrading protrusions present in invasive cancer cells. Knockdown of Tks5, a Src substrate that is required for invadopodia formation in mammalian cells blocked formation of the protrusions and rescued invasion in mlt. Activation of Src-signaling induced invadopodia-like protrusions in wild type epithelial cells, however the cells did not migrate into the tissue stroma, thus indicating that the protrusions were required but not sufficient for invasion in this in vivo model. Transcriptional profiling experiments showed that genes responsive to reactive oxygen species (ROS) were upregulated in mlt larvae. ROS generators induced invadopodia-like protrusions and invasion in heterozygous mlt larvae but had no effect in wild type larvae. Co-activation of oncogenic Ras and Wnt signaling enhanced the responsiveness of mlt heterozygotes to the ROS generators. These findings present the first direct evidence that invadopodia play a role in tissue cell invasion in vivo. In addition, they identify an inducible physical signaling pathway sensitive to redox and oncogenic signaling that can drive this process.

  8. Characterization and classification of zebrafish brain morphology mutants

    PubMed Central

    Lowery, Laura Anne; De Rienzo, Gianluca; Gutzman, Jennifer H.; Sive, Hazel

    2010-01-01

    The mechanisms by which the vertebrate brain achieves its three-dimensional structure are clearly complex, requiring the functions of many genes. Using the zebrafish as a model, we have begun to define genes required for brain morphogenesis, including brain ventricle formation, by studying 16 mutants previously identified as having embryonic brain morphology defects. We report the phenotypic characterization of these mutants at several time-points, using brain ventricle dye injection, imaging, and immunohistochemistry with neuronal markers. Most of these mutants display early phenotypes, affecting initial brain shaping, while others show later phenotypes, affecting brain ventricle expansion. In the early phenotype group, we further define four phenotypic classes and corresponding functions required for brain morphogenesis. Although we did not use known genotypes for this classification, basing it solely on phenotypes, many mutants with defects in functionally related genes clustered in a single class. In particular, class 1 mutants show midline separation defects, corresponding to epithelial junction defects; class 2 mutants show reduced brain ventricle size; class 3 mutants show midbrain-hindbrain abnormalities, corresponding to basement membrane defects; and class 4 mutants show absence of ventricle lumen inflation, corresponding to defective ion pumping. Later brain ventricle expansion requires the extracellular matrix, cardiovascular circulation, and transcription/splicing-dependent events. We suggest that these mutants define processes likely to be used during brain morphogenesis throughout the vertebrates. PMID:19051268

  9. Smooth Muscle Tension Induces Invasive Remodeling of the Zebrafish Intestine

    PubMed Central

    Seiler, Christoph; Davuluri, Gangarao; Abrams, Joshua; Byfield, Fitzroy J.; Janmey, Paul A.; Pack, Michael

    2012-01-01

    The signals that initiate cell invasion are not well understood, but there is increasing evidence that extracellular physical signals play an important role. Here we show that epithelial cell invasion in the intestine of zebrafish meltdown (mlt) mutants arises in response to unregulated contractile tone in the surrounding smooth muscle cell layer. Physical signaling in mlt drives formation of membrane protrusions within the epithelium that resemble invadopodia, matrix-degrading protrusions present in invasive cancer cells. Knockdown of Tks5, a Src substrate that is required for invadopodia formation in mammalian cells blocked formation of the protrusions and rescued invasion in mlt. Activation of Src-signaling induced invadopodia-like protrusions in wild type epithelial cells, however the cells did not migrate into the tissue stroma, thus indicating that the protrusions were required but not sufficient for invasion in this in vivo model. Transcriptional profiling experiments showed that genes responsive to reactive oxygen species (ROS) were upregulated in mlt larvae. ROS generators induced invadopodia-like protrusions and invasion in heterozygous mlt larvae but had no effect in wild type larvae. Co-activation of oncogenic Ras and Wnt signaling enhanced the responsiveness of mlt heterozygotes to the ROS generators. These findings present the first direct evidence that invadopodia play a role in tissue cell invasion in vivo. In addition, they identify an inducible physical signaling pathway sensitive to redox and oncogenic signaling that can drive this process. PMID:22973180

  10. Termination of pregnancy at very early gestation without visible yolk sac on ultrasound.

    PubMed

    Heller, Rebecca; Cameron, Sharon

    2015-04-01

    Requests for termination of pregnancy (TOP) at very early gestation (≤6 weeks) can prove challenging for abortion services as the ultrasound feature usually accepted as definitive evidence of an intrauterine pregnancy (IUP), the presence of a yolk sac within a gestational sac, may not yet be evident. In 2011 the Edinburgh TOP service introduced a protocol permitting women to proceed to treatment without further investigations provided that ultrasound showed the features of an eccentrically placed gestational sac (≥3 mm) with a decidual reaction, and there were no signs, symptoms or risk factors for ectopic pregnancy. A retrospective audit was conducted of outcomes of women presenting for TOP at ≤6 weeks' gestation over a 2-year period using the hospital computerised database. A total of 1155 women presented for TOP with an ultrasound gestational age of ≤6 weeks. Of these, 1030 (89%) had ultrasound evidence of a yolk sac. Eighty-seven women (7.5%) had an eccentrically placed gestational sac with a decidual reaction. All 87 women fulfilled our criteria to proceed to medical TOP, and 66 did so. In the remaining 21 cases, further investigations were performed before they proceeded to medical TOP. Two (0.17%) medical TOPs failed, both in women whose initial ultrasound had shown a yolk sac. Women with ultrasound features consistent with a very early IUP (≥3 mm eccentrically placed gestational sac with a decidual reaction) and without signs, symptoms or risk factors for ectopic pregnancy can proceed directly to medical TOP without the need for delay for further ultrasonography. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  11. Preparation of immunoglobulin Y from egg yolk using ammonium sulfate precipitation and ion exchange chromatography.

    PubMed

    Ko, K Y; Ahn, D U

    2007-02-01

    The objective of this study was to develop an economical, simple, and large-scale separation method for IgY from egg yolk. Egg yolk diluted with 9 volumes of cold water was centrifuged after adjusting the pH to 5.0. The supernatant was added with 0.01% charcoal or 0.01% carrageenan and centrifuged at 2,800 x g for 30 min. The supernatant was filtered through a Whatman no. 1 filter paper and then the filtrate was concentrated to 20% original volume using ultrafiltration. The concentrated solution was further purified using either cation exchange chromatography or ammonium sulfate precipitation. For the cation exchange chromatography method, the concentrated sample was loaded onto a column equilibrated with 20 mM citrate-phosphate buffer at pH 4.8 and eluted with 200 mM citrate-phosphate buffer at pH 6.4. For the ammonium sulfate precipitation method, the concentrated sample was twice precipitated with 40% ammonium sulfate solution at pH 9.0. The yield and purity of IgY were determined by ELISA and electrophoresis. The yield of IgY from the cation exchange chromatography method was 30 to 40%, whereas that of the ammonium sulfate precipitation was 70 to 80%. The purity of IgY from the ammonium sulfate method was higher than that of the cation exchange chromatography. The cation exchange chromatography could handle only a small amount of samples, whereas the ammonium sulfate precipitation could handle a large volume of samples. This suggests that ammonium sulfate precipitation was a more efficient and useful purification method than cation exchange chromatography for the large-scale preparation of IgY from egg yolk.

  12. Evaluation of suspension array analysis for detection of egg yolk antibodies against Salmonella Enteritidis.

    PubMed

    Thomas, M E; Klinkenberg, D; Bergwerff, A A; van Eerden, E; Stegeman, J A; Bouma, A

    2010-06-01

    Salmonella enterica serovar Enteritidis (SE) is an important source of food-related diarrhoea in humans, and table eggs are considered the primordial source of contamination of the human food chain. Using eggs collected at egg-packing stations as samples could be a convenient strategy to detect colonization of layer flocks. The aim of this study was to evaluate egg yolk anti-Salmonella antibody detection using suspension array analysis. An egg yolk panel from contact-infected and non-colonized laying hens was used for the evaluation. Receiver Operating Characteristic (ROC) curves were generated to define a cut-off value and to assess the overall accuracy of the assay. The diagnostic sensitivity and specificity were estimated by maximum likelihood. Sensitivity was quantified on hen level and on sample level, and also quantified as a function of time since colonization. The area under the ROC curve was estimated at 0.984 (se 0.006, P<0.001). Of all colonized contact-infected hens, 67.6% [95% CI: 46.8, 100] developed an antibody response, which was detectable 17.4 days [14.3, 26.9] after colonization. In total, 98% [95.4, 99.4] of the 'immunopositive' hens had test positive eggs. The overall sensitivity of the immunological test was 66.7% [45.9, 98.7] and the specificity was 98.5% [97.8, 99.1]. This study provided essential parameters for optimizing surveillance programs based on detection of antibodies, and indicates that immunology based on examination of egg yolk gives important information about the Salmonella status of the flock. (c) 2010 Elsevier B.V. All rights reserved.

  13. Protection Efficacy of Multivalent Egg Yolk Immunoglobulin against Eimeria tenella Infection in Chickens

    PubMed Central

    Xu, JJ; Ren, CZ; Wang, SS; Liu, DD; Cao, LQ; Tao, JP

    2013-01-01

    Background To control avian coccidiosis with drug-independent strategy effectively and safely, multivalent hyperimmune egg yolk immunoglobulin (IgY) was prepared and its ability to protect against Eimeria tenella infection was evaluated. Methods Hens were orally immunized with live oocysts of 5 species of Eimeria for six times, antibody titers in serum and yolk were monitored by indirect enzyme-linked immunosorbent assay. The specific IgY was isolated, purified and lyophilized. IgY powder was orally administrated as dietary supplement in newly hatched chicks at various dosages. Birds were orally challenged with 10000 sporulated oocysts of E. tenella at 10 days of age, weighed and killed at 8 days post challenge, and the protective effect was assessed. Results The averge yeid of IgY was 9.2 mg/ml yolk, the antibody titer of IgY reached to 1:163840 per mg with the purity up to 98%. Chickens fed IgY resulted in reduced mortality, increased body weight gain (BWG), reduced oocyst shedding, reduced caecal lesion score and increased anti-coccidial index. In terms of BWG and caecal lesion, IgY significantly enhanced the resistance of bird at ≥ 0.05% of IgY in the diet when compared with the challenged control group (P<0.05). No significant difference was observed at dosage ≥ 0.5% and 1.0% when BWG and caecal lesion were compared with the sodium salinomycin control group, respectively (P>0.05). Conclusion Supplementing newly hatched chicks with Eimeria-specific IgY represents a promising strategy to prevent avian coccidiosis. PMID:24454440

  14. A bioenergetic model for zebrafish Danio rerio (Hamilton)

    Chizinski, C.J.; Sharma, Bibek; Pope, K.L.; Patino, R.

    2008-01-01

    A bioenergetics model was developed from observed consumption, respiration and growth rates for zebrafish Danio rerio across a range (18-32?? C) of water temperatures, and evaluated with a 50 day laboratory trial at 28?? C. No significant bias in variable estimates was found during the validation trial; namely, predicted zebrafish mass generally agreed with observed mass. ?? 2008 The Authors.

  15. Mapping the zebrafish brain methylome using reduced representation bisulfite sequencing

    PubMed Central

    Chatterjee, Aniruddha; Ozaki, Yuichi; Stockwell, Peter A; Horsfield, Julia A; Morison, Ian M; Nakagawa, Shinichi

    2013-01-01

    Reduced representation bisulfite sequencing (RRBS) has been used to profile DNA methylation patterns in mammalian genomes such as human, mouse and rat. The methylome of the zebrafish, an important animal model, has not yet been characterized at base-pair resolution using RRBS. Therefore, we evaluated the technique of RRBS in this model organism by generating four single-nucleotide resolution DNA methylomes of adult zebrafish brain. We performed several simulations to show the distribution of fragments and enrichment of CpGs in different in silico reduced representation genomes of zebrafish. Four RRBS brain libraries generated 98 million sequenced reads and had higher frequencies of multiple mapping than equivalent human RRBS libraries. The zebrafish methylome indicates there is higher global DNA methylation in the zebrafish genome compared with its equivalent human methylome. This observation was confirmed by RRBS of zebrafish liver. High coverage CpG dinucleotides are enriched in CpG island shores more than in the CpG island core. We found that 45% of the mapped CpGs reside in gene bodies, and 7% in gene promoters. This analysis provides a roadmap for generating reproducible base-pair level methylomes for zebrafish using RRBS and our results provide the first evidence that RRBS is a suitable technique for global methylation analysis in zebrafish. PMID:23975027

  16. Characterization of behavioral and endocrine effects of LSD on zebrafish.

    PubMed

    Grossman, Leah; Utterback, Eli; Stewart, Adam; Gaikwad, Siddharth; Chung, Kyung Min; Suciu, Christopher; Wong, Keith; Elegante, Marco; Elkhayat, Salem; Tan, Julia; Gilder, Thomas; Wu, Nadine; Dileo, John; Cachat, Jonathan; Kalueff, Allan V

    2010-12-25

    Lysergic acid diethylamide (LSD) is a potent hallucinogenic drug that strongly affects animal and human behavior. Although adult zebrafish (Danio rerio) are emerging as a promising neurobehavioral model, the effects of LSD on zebrafish have not been investigated previously. Several behavioral paradigms (the novel tank, observation cylinder, light-dark box, open field, T-maze, social preference and shoaling tests), as well as modern video-tracking tools and whole-body cortisol assay were used to characterize the effects of acute LSD in zebrafish. While lower doses (5-100 microg/L) did not affect zebrafish behavior, 250 microg/L LSD increased top dwelling and reduced freezing in the novel tank and observation cylinder tests, also affecting spatiotemporal patterns of activity (as assessed by 3D reconstruction of zebrafish traces and ethograms). LSD evoked mild thigmotaxis in the open field test, increased light behavior in the light-dark test, reduced the number of arm entries and freezing in the T-maze and social preference test, without affecting social preference. In contrast, LSD affected zebrafish shoaling (increasing the inter-fish distance in a group), and elevated whole-body cortisol levels. Overall, our findings show sensitivity of zebrafish to LSD action, and support the use of zebrafish models to study hallucinogenic drugs of abuse. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  17. Identifying Structural Alerts Based on Zebrafish Developmental Morphological Toxicity (TDS)

    EPA Science Inventory

    Zebrafish constitute a powerful alternative animal model for chemical hazard evaluation. To provide an in vivo complement to high-throughput screening data from the ToxCast program, zebrafish developmental toxicity screens were conducted on the ToxCast Phase I (Padilla et al., 20...

  18. DRUG EFFECTS ON THE LOCOMOTOR ACTIVITY OF LARVAL ZEBRAFISH.

    EPA Science Inventory

    As part of an effort to develop a rapid in vivo screen for EPA’s prioritization of toxic chemicals, we have begun to characterize the locomotor activity of zebrafish (Danio rerio) larvae and the effects of prototype drugs. Zebrafish larvae (6-7 days post-fertilization) were indiv...

  19. Yolk protein is expressed in the insect testis and interacts with sperm

    PubMed Central

    Bebas, Piotr; Kotwica, Joanna; Joachimiak, Ewa; Giebultowicz, Jadwiga M

    2008-01-01

    Background Male and female gametes follow diverse developmental pathways dictated by their distinct roles in fertilization. While oocytes of oviparous animals accumulate yolk in the cytoplasm, spermatozoa slough off most of their cytoplasm in the process of individualization. Mammalian spermatozoa released from the testis undergo extensive modifications in the seminal ducts involving a variety of glycoproteins. Ultrastructural studies suggest that glycoproteins are involved in sperm maturation in insects; however, their characterization at the molecular level is lacking. We reported previously that the circadian clock controls sperm release and maturation in several insect species. In the moth, Spodoptera littoralis, the secretion of glycoproteins into the seminal fluid occurs in a daily rhythmic pattern. The purpose of this study was to characterize seminal fluid glycoproteins in this species and elucidate their role in the process of sperm maturation. Results We collected seminal fluid proteins from males before and after daily sperm release. These samples were separated by 2-D gel electrophoresis, and gels were treated with a glycoprotein-detecting probe. We observed a group of abundant glycoproteins in the sample collected after sperm release, which was absent in the sample collected before sperm release. Sequencing of these glycoproteins by mass spectroscopy revealed peptides bearing homology with components of yolk, which is known to accumulate in developing oocytes. This unexpected result was confirmed by Western blotting demonstrating that seminal fluid contains protein immunoreactive to antibody against yolk protein YP2 produced in the follicle cells surrounding developing oocytes. We cloned the fragment of yp2 cDNA from S. littoralis and determined that it is expressed in both ovaries and testes. yp2 mRNA and YP2 protein were detected in the somatic cyst cells enveloping sperm inside the testis. During the period of sperm release, YP2 protein appears in

  20. [Laser Raman and infrared spectrum analysis of low-density lipoproteins purified from hen egg yolk].

    PubMed

    Xue, Hui-jun; Sun, Run-guang; Wang, Xiao-mei; Chang, Yi-guang

    2010-11-01

    During the experiment, diversified proteins were separated from hen egg yolk by ammonium sulphate rapid fractionation, and pure LDL was obtained after filtrating through Sephadex G-200 chromatography. After the qualitative detection of SDS-PAGE, the authors discovered that LDL consists of five major apoprotein. The Raman and infrared spectrum showed CH2 asymmetric stretching and symmetric stretching mode. However, the authors found C==O stretching vibrations of protein peptide bonds and N+ (CH3)3 asymmetric stretching vibration from the choline group in phospholipids. Laser Raman and infrared spectrum analysis of LDL provided useful information for studying their structure.

  1. Zebrafish models for translational neuroscience research: from tank to bedside

    PubMed Central

    Stewart, Adam Michael; Braubach, Oliver; Spitsbergen, Jan; Gerlai, Robert; Kalueff, Allan V.

    2014-01-01

    The zebrafish (Danio rerio) is emerging as a new important species for studying mechanisms of brain function and dysfunction. Focusing on selected central nervous system (CNS) disorders (brain cancer, epilepsy, and anxiety) and using them as examples, we discuss the value of zebrafish models in translational neuroscience. We further evaluate the contribution of zebrafish to neuroimaging, circuit level, and drug discovery research. Outlining the role of zebrafish in modeling a wide range of human brain disorders, we also summarize recent applications and existing challenges in this field. Finally, we emphasize the potential of zebrafish models in behavioral phenomics and high-throughput genetic/small molecule screening, which is critical for CNS drug discovery and identifying novel candidate genes. PMID:24726051

  2. Heart Repair and Regeneration: Recent Insights from Zebrafish Studies

    PubMed Central

    Lien, Ching-Ling; Harrison, Michael R.; Tuan, Tai-Lan; Starnes, Vaughn A

    2012-01-01

    Cardiovascular disease is the leading cause of death in United States and worldwide. Failure to properly repair or regenerate damaged cardiac tissues after myocardial infarction is a major cause of heart failure. In contrast to humans and other mammals, zebrafish hearts regenerate after substantial injury or tissue damage. Here, we review recent progress in studying zebrafish heart regeneration, addressing the molecular and cellular responses in the three tissue layers of the heart: myocardium, epicardium, and endocardium. We also compare different injury models utilized to study zebrafish heart regeneration, and discuss the differences in responses to injury between mammalian and zebrafish hearts. By learning how zebrafish hearts regenerate naturally, we can better design therapeutic strategies for repairing human hearts after myocardial infarction. PMID:22818295

  3. Physical exercise improves learning in zebrafish, Danio rerio.

    PubMed

    Luchiari, Ana Carolina; Chacon, Diana Marques Martins

    2013-11-01

    Zebrafish is an ideal vertebrate model for neuroscience studies focusing on learning and memory. Although genetic manipulation of zebrafish is available, behavioral protocols are often lacking. In this study we tested whether physical activity can facilitate zebrafish's learning process in an associative conditioning task. Learning was inferred by the approach of the feeding area just after the conditioned stimulus (light). Unexercised zebrafish showed conditioning response from the 5th testing day while fish previously submitted to swim against the water current showed learning by the 3rd day of testing. It seems that physical activity may accelerate associative learning response in zebrafish, indicating the benefits of exercise for cognitive processes. We suggest that this preliminary work could be useful for high throughput screening. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Advancing epilepsy treatment through personalized genetic zebrafish models.

    PubMed

    Griffin, A; Krasniak, C; Baraban, S C

    2016-01-01

    With an increase in the number of disease causing genetic mutations identified from epilepsy cohorts, zebrafish are proving to be an attractive vertebrate model for functional analysis of these allele variants. Not only do zebrafish have conserved gene functions, but larvae harboring mutations in identified human epileptic genes show spontaneous seizure activity and mimic the convulsive behavioral movements observed in humans. With zebrafish being compatible with medium to high-throughput screening, they are also proving to be a unique and powerful system for early preclinical drug screening, including novel target identification, pharmacology, and toxicology. Additionally, with recent advances in genomic engineering technologies, it is now possible to study the precise pathophysiology of patient-specific gene mutations in zebrafish. The following sections highlight how the unique attributes of zebrafish, in combination with genetic modifications, are continuing to transform our understanding of epilepsy and help identify personalized therapeutics for specific patient cohorts. © 2016 Elsevier B.V. All rights reserved.

  5. Development of sensory systems in zebrafish (Danio rerio)

    NASA Technical Reports Server (NTRS)

    Moorman, S. J.

    2001-01-01

    Zebrafish possess all of the classic sensory modalities: taste, tactile, smell, balance, vision, and hearing. For each sensory system, this article provides a brief overview of the system in the adult zebrafish followed by a more detailed overview of the development of the system. By far the majority of studies performed in each of the sensory systems of the zebrafish have involved some aspect of molecular biology or genetics. Although molecular biology and genetics are not major foci of the paper, brief discussions of some of the mutant strains of zebrafish that have developmental defects in each specific sensory system are included. The development of the sensory systems is only a small sampling of the work being done using zebrafish and provides a mere glimpse of the potential of this model for the study of vertebrate development, physiology, and human disease.

  6. Macrophage–Microbe Interactions: Lessons from the Zebrafish Model

    PubMed Central

    Yoshida, Nagisa; Frickel, Eva-Maria; Mostowy, Serge

    2017-01-01

    Macrophages provide front line defense against infections. The study of macrophage–microbe interplay is thus crucial for understanding pathogenesis and infection control. Zebrafish (Danio rerio) larvae provide a unique platform to study macrophage–microbe interactions in vivo, from the level of the single cell to the whole organism. Studies using zebrafish allow non-invasive, real-time visualization of macrophage recruitment and phagocytosis. Furthermore, the chemical and genetic tractability of zebrafish has been central to decipher the complex role of macrophages during infection. Here, we discuss the latest developments using zebrafish models of bacterial and fungal infection. We also review novel aspects of macrophage biology revealed by zebrafish, which can potentiate development of new therapeutic strategies for humans. PMID:29250076

  7. Examination of a Palatogenic Gene Program in Zebrafish

    PubMed Central

    Swartz, Mary E.; Sheehan-Rooney, Kelly; Dixon, Michael J.; Eberhart, Johann K.

    2011-01-01

    Human palatal clefting is debilitating and difficult to rectify surgically. Animal models enhance our understanding of palatogenesis and are essential in strategies designed to ameliorate palatal malformations in humans. Recent studies have shown that the zebrafish palate, or anterior neurocranium, is under similar genetic control to the amniote palatal skeleton. We extensively analyzed palatogenesis in zebrafish to determine the similarity of gene expression and function across vertebrates. By 36 hpf palatogenic cranial neural crest cells reside in homologous regions of the developing face compared to amniote species. Transcription factors and signaling molecules regulating mouse palatogenesis are expressed in similar domains during palatogenesis in zebrafish. Functional investigation of a subset of these genes, fgf10a, tgfb2, pax9 and smad5 revealed their necessity in zebrafish palatogenesis. Collectively, these results suggest that the gene regulatory networks regulating palatogenesis may be conserved across vertebrate species, demonstrating the utility of zebrafish as a model for palatogenesis. PMID:22016187

  8. Membrane stabilizer

    DOEpatents

    Mingenbach, W.A.

    1988-02-09

    A device is provided for stabilizing a flexible membrane secured within a frame, wherein a plurality of elongated arms are disposed radially from a central hub which penetrates the membrane, said arms imposing alternately against opposite sides of the membrane, thus warping and tensioning the membrane into a condition of improved stability. The membrane may be an opaque or translucent sheet or other material. 10 figs.

  9. UNUSUAL FINDINGS IN ZEBRAFISH, DANIO RERIO, FROM TOXICOLOGICAL STUDIES AND THE ZEBRAFISH INTERNATIONAL RESOURCE CENTER DIAGNOSTIC SERVICE

    EPA Science Inventory

    A number of interesting and unusual lesions have been diagnosed in zebrafish that have been evaluated from toxicological studies or submitted as cases to the Diagnostic Service at Oregon State University. Lesions were observed in various wild-type and mutant lines of zebrafish an...

  10. Epididymal sperm from Spix's yellow-toothed cavies sperm successfully cryopreserved in Tris extender with 6% glycerol and 20% egg yolk.

    PubMed

    Silva, Andréia M; Praxedes, Erica C G; Campos, Lívia B; Bezerra, Luana G P; Moreira, Samara S J; Maia, Keilla M; Souza, Ana L P; Silva, Alexandre R

    2018-04-01

    As a non-threatened hystricognath rodent species, Spix's yellow-toothed cavies can be used as a model for the development of assisted reproductive techniques for the conservation of closely related species. The objective was to establish a functional protocol for cryopreservation of epididymal sperm from these cavies. Twelve sexually mature males, ∼2 y old and weighing ∼300 g, were euthanized. Sperm were recovered by retrograde flushing of the vas deferens and cauda epididymis with Tris extender. Thereafter, sperm were extended in Tris plus 20% egg yolk, with 3%, 6% or 9% glycerol or dimethyl sulfoxide (DMSO), placed in 0.25 mL straws and cryopreserved in liquid nitrogen. Sperm concentration, motility (using computer-assisted sperm analysis; CASA), plasma membrane integrity, osmotic response, morphology and sperm binding-ability were determined in fresh and frozen-thawed sperm. For most sperm endpoints, glycerol was a more desirable cryoprotectant than DMSO. Data (mean ± SEM) were similar with use of 3%, 6%, and 9% glycerol (P > 0.05) in osmotic response (40.66 ± 6.3%, 42.5 ± 7.1%, and 39.5 ± 5.0% respectably), and membrane integrity (55.17 ± 5.5%, 68.4 ± 4.1%, and 59.1 ± 4.9% respectably). Among concentrations assessed, the use of 6% glycerol resulted in the greatest (P < 0.05) post-thaw values for total motility (60.9 ± 4.4%), rapid subpopulation motility (27.7 ± 3.1%) and sperm-binding capability (227.0 ± 20.2). In conclusion, epididymal sperm from the Spix's yellow-toothed cavies (G. spixii) are optimally cryopreserved in Tris extender with 6% glycerol and 20% egg yolk. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Effects of ammonium-based ionic liquids and 2,4-dichlorophenol on the phospholipid fatty acid composition of zebrafish embryos.

    PubMed

    Piotrowska, Aleksandra; Syguda, Anna; Wyrwas, Bogdan; Chrzanowski, Lukasz; Luckenbach, Till; Heipieper, Hermann J

    2018-01-01

    Ionic liquids consisting of a combination of herbicidal anions with a quaternary ammonium cation act as efficient herbicides, which are under consideration to be used in the agriculture. In the present study, we used embryos of the zebrafish (Danio rerio) as a model to assess the toxic potential of ammonium-based ionic liquids for aquatic organisms. As we assumed interference of the partially hydrophobic ionic liquid cation with lipids, we investigated the adaptation response in the lipid composition of the zebrafish embryos, triggered by the ionic compound. Therefore, the impact of ammonium-based ionic liquids with different lengths of the alkyl chain ([C6,C6,C1,C1N][Br], [C8,C8,C1,C1N][Br]) on the phospholipid fatty acid (PLFA) profile of zebrafish embryos up to 72 hours post fertilization (hpf) was examined. Furthermore, the changes in the unsaturation index (UI) of PLFAs, as the sum parameter of membrane fluidity in eukaryotic cells, were presented. The PLFA's UI in the zebrafish embryos upon exposure to quaternary ammonium salts was compared to the UI of the embryos upon exposure to nonionic 2,4-dichlorophenol, which has a similar hydrophobicity but is structurally different to [C8,C8,C1,C1N][Br]. It was shown that for ammonium-based ionic liquid precursors non-specific mode of action occurs and the toxic effect on lipid composition of zebrafish embryos can be well predicted based on chemical properties, like hydrophobicity. Furthermore, the changes in PLFAs, expressed by the UI, can be useful to study toxic effects of organic contamination. However, for zebrafish embryos, after ionic liquids and 2,4-DCP exposure, the changes were observed at high lethal concentrations, which caused the incidence of lethality of 30 and 50% of a group of test animals.

  12. Effects of ammonium-based ionic liquids and 2,4-dichlorophenol on the phospholipid fatty acid composition of zebrafish embryos

    PubMed Central

    Piotrowska, Aleksandra; Syguda, Anna; Wyrwas, Bogdan; Chrzanowski, Lukasz; Luckenbach, Till

    2018-01-01

    Ionic liquids consisting of a combination of herbicidal anions with a quaternary ammonium cation act as efficient herbicides, which are under consideration to be used in the agriculture. In the present study, we used embryos of the zebrafish (Danio rerio) as a model to assess the toxic potential of ammonium-based ionic liquids for aquatic organisms. As we assumed interference of the partially hydrophobic ionic liquid cation with lipids, we investigated the adaptation response in the lipid composition of the zebrafish embryos, triggered by the ionic compound. Therefore, the impact of ammonium-based ionic liquids with different lengths of the alkyl chain ([C6,C6,C1,C1N][Br], [C8,C8,C1,C1N][Br]) on the phospholipid fatty acid (PLFA) profile of zebrafish embryos up to 72 hours post fertilization (hpf) was examined. Furthermore, the changes in the unsaturation index (UI) of PLFAs, as the sum parameter of membrane fluidity in eukaryotic cells, were presented. The PLFA’s UI in the zebrafish embryos upon exposure to quaternary ammonium salts was compared to the UI of the embryos upon exposure to nonionic 2,4-dichlorophenol, which has a similar hydrophobicity but is structurally different to [C8,C8,C1,C1N][Br]. It was shown that for ammonium-based ionic liquid precursors non-specific mode of action occurs and the toxic effect on lipid composition of zebrafish embryos can be well predicted based on chemical properties, like hydrophobicity. Furthermore, the changes in PLFAs, expressed by the UI, can be useful to study toxic effects of organic contamination. However, for zebrafish embryos, after ionic liquids and 2,4-DCP exposure, the changes were observed at high lethal concentrations, which caused the incidence of lethality of 30 and 50% of a group of test animals. PMID:29342167

  13. Protection of rats against dental caries by passive immunization with hen-egg-yolk antibody (IgY).

    PubMed

    Otake, S; Nishihara, Y; Makimura, M; Hatta, H; Kim, M; Yamamoto, T; Hirasawa, M

    1991-03-01

    Hen-egg-yolk antibody (IgY) was prepared against Streptococcus mutans MT8148 serotype c that was cultivated in medium containing sucrose, and it was used in passive caries-immunity studies. Specific pathogen-free rats infected with S. mutans MT8148 (c) and fed with a cariogenic diet containing more than 2% immune yolk powder developed significantly lower caries scores than did the ones infected with the same strain and fed with a diet containing only control yolk powder obtained from non-immunized hens. Similar results were obtained in an experiment with rats infected with S. mutans JC-2 (c) strain. Rats provided a diet supplemented with 0.5% immune water-soluble protein fraction containing S. mutans-specific IgY and challenged with S. mutans MT8148 exhibited significantly fewer caries lesions, compared with control rats on the normal diet.

  14. Yolk embolism associated with trauma in vitellogenic sea turtles in Florida (USA): a review of 11 cases.

    PubMed

    Stacy, Brian A; Foley, Allen; Garner, Michael M; Mettee, Nancy

    2013-12-01

    Case information and postmortem examination findings are presented for 11 adult female sea turtles in reproductive form that died in Florida, USA. All had abundant, large vitellogenic follicles, and most were either gravid or had recently nested. Species included six loggerheads (Caretta caretta) and five green turtles (Chelonia mydas). Identified proximate causes of death included falls or entrapment by obstructions on nesting beaches, burial under collapsed dunes, and other traumatic injuries of different causes. Evidence of yolk embolization was found in 10 cases and suspected in an 11th turtle. Ten turtles also had various amounts of free intracoelomic yolk. Although the effects of yolk embolization are uncertain at this time, precedence of pathologic importance in other species suggests that embolism may complicate traumatic injuries, including seemingly minor events.

  15. An evaluation of soybean lecithin as an alternative to avian egg yolk in the cryopreservation of fish sperm.

    PubMed

    Yildiz, Cengiz; Bozkurt, Yusuf; Yavas, Ilker

    2013-08-01

    Plant-derived lecithin has been used as a more sanitary alternative to avian egg yolk in livestock sperm cryopreservation protocols but its efficacy for cryopreserving fish sperm has not previously been tested comparatively. Here various concentrations of soybean lecithin were evaluated for the cryopreservation of carp (Cyprinus carpio) sperm. Sexually mature fish were induced to spermiation and ovulation with ovopel. The extenders were prepared by using 300 mM glucose, 10% DMSO, supplemented with different ratios of lecithin (5%, 10%, 15%, and 20%) and 10% egg yolk (control I). Negative control was made without egg yolk and soybean lecithin (control II). The pooled semen was diluted separately at ratio of 1:3 (v/v) by using egg yolk and soybean-based extenders. Diluted semen placed into 0.25 ml straws were equilibrated at 4 °C for 15 min and frozen in liquid nitrogen vapor. Fertilization was conducted using a ratio of 1 × 10(5)spermatozoa/egg. Supplementation of 10% lecithin to extender showed the best cryoprotective effect for sperm motility and duration of motility against freezing damage compared to 15%, 20% and control II groups (p<0.05). Cryopreserved sperm with extender containing 10% lecithin provided a greater result in terms of fertilization success when compared to extenders containing 20% lecithin or control II (p<0.05). It is concluded that the animal protein-free extender containing 10% soybean lecithin has a similar cryoprotective actions with conventional egg yolk-based extender against freezing damages and fertilization. Therefore, soybean lecithin is a suitable alternative to avian egg yolk for the cryopreservation of fish sperm. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. In vitro comparison of egg yolk-based and soybean lecithin-based extenders for cryopreservation of ram semen.

    PubMed

    Forouzanfar, M; Sharafi, M; Hosseini, S M; Ostadhosseini, S; Hajian, M; Hosseini, L; Abedi, P; Nili, N; Rahmani, H R; Nasr-Esfahani, M H

    2010-03-01

    Substitution of egg yolk with soybean lecithin may reduce hygienic risks in extenders. Though a few studies have been performed on the effect of soybean lecithin in bull, to date evaluation of ram semen in vitro fertility after cryopreservation with use of soybean lecithin has not been studied. This study assessed the effect of 1% or 2% (wt/vol) soybean lecithin (L1 or L2) or 15% or 20% (vol/vol) egg yolk (E15 or E20) supplemented with 5% or 7% glycerol (G5 or G7) in a Tris-based medium for cryopreservation of ram (Oviss arries) semen. Although no significant difference was observed in pattern of capacitation, the best results in terms of sperm motility, viability postthaw, and cleavage rates were observed with L1G7 (51.9+/-4.8%, 48.1+/-3.5%, and 79.6+/-3.9%, respectively) and E20G7 (51.8+/-2.9%, 46.7+/-4.0%, and 72.9+/-6.4%, respectively). Our results also showed that 1% lecithin and 20% egg yolk was superior to 2% lecithin and 15% egg yolk. In terms of cleavage rate, 7% glycerol was superior to 5% glycerol. No significant difference was obtained between groups in terms of blastocysts rate per cleaved embryo. Therefore, we concluded that the optimal concentration of lecithin and egg yolk is 1% and 20%, respectively, along with 7% glycerol. In addition, our results suggest that lecithin can be used as a substitute for egg yolk. Copyright 2010 Elsevier Inc. All rights reserved.

  17. Chemical Compositions of Egg Yolks and Egg Quality of Laying Hens Fed Prebiotic, Probiotic, and Synbiotic Diets.

    PubMed

    Tang, Shirley Gee Hoon; Sieo, Chin Chin; Kalavathy, Ramasamy; Saad, Wan Zuhainis; Yong, Su Ting; Wong, Hee Kum; Ho, Yin Wan

    2015-08-01

    A 16-wk feeding experiment was conducted to investigate the effects of a prebiotic, isomaltooligosaccharide (IMO), a probiotic, PrimaLac®, and their combination as a synbiotic on the chemical compositions of egg yolks and the egg quality of laying hens. One hundred and sixty 16-wk-old Hisex Brown pullets were randomly assigned to 4 dietary treatments: (i) basal diet (control), (ii) basal diet + 1% IMO (PRE), (iii) basal diet + 0.1% PrimaLac® (PRO), and (iv) basal diet + 1% IMO + 0.1% PrimaLac® (SYN). PRE, PRO, or SYN supplementation not only significantly (P < 0.05) decreased the egg yolk cholesterol (24- and 28-wk-old) and total saturated fatty acids (SFA; 28-, 32-, and 36-wk-old), but also significantly (P < 0.05) increased total unsaturated fatty acids (UFA; 28-, 32-, and 36-wk-old), total omega 6 and polyunsaturated fatty acids (PUFA), including linoleic and alpha-linolenic acid levels in the eggs (28-wk-old). However, the total lipids, carotenoids, and tocopherols in the egg yolks were similar among all dietary treatments in the 24-, 28-, 32-, and 36-wk-old hens. Egg quality (Haugh unit, relative weights of the albumen and yolk, specific gravity, shell thickness, and yolk color) was not affected by PRE, PRO, or SYN supplementation. The results indicate that supplementations with IMO and PrimaLac® alone or in combination as a synbiotic might be useful for improving the cholesterol content and modifying the fatty acid compositions of egg yolk without affecting the quality of eggs from laying hens between 24 and 36 wk of age. © 2015 Institute of Food Technologists®

  18. Yolk-shell structured Sb@C anodes for high energy Na-ion batteries

    SciT

    Song, Junhua; Yan, Pengfei; Luo, Langli

    Despite great advances in sodium-ion battery developments, the search for high energy and stable anode materials remains a challenge. Alloy or conversion-typed anode materials are attractive candidates of high specific capacity and low voltage potential, yet their applications are hampered by the large volume expansion and hence poor electrochemical reversibility and fast capacity fade. Here, we use antimony (Sb) as an example to demonstrate the use of yolk-shell structured anodes for high energy Na-ion batteries. The Sb@C yolk-shell structure prepared by controlled reduction and selective removal of Sb2O3 from carbon coated Sb2O3 nanoparticles can accommodate the Sb swelling upon sodiationmore » and improve the structural/electrical integrity against pulverization. It delivers a high specific capacity of ~554 mAh•g-1, good rate capability (315 mhA•g-1 at 10C rate) and long cyclability (92% capacity retention over 200 cycles). Full-cells of O3-Na0.9[Cu0.22Fe0.30Mn0.48]O2 cathodes and Sb@C-hard carbon composite anodes demonstrate a high specific energy of ~130 Wh•kg-1 (based on the total mass of cathode and anode) in the voltage range of 2.0-4.0 V, ~1.5 times energy of full-cells with similar design using hard carbon anodes.« less

  19. Yolk-shell structured Sb@C anodes for high energy Na-ion batteries

    SciT

    Song, Junhua; Yan, Pengfei; Luo, Langli

    Despite great advances in sodium-ion battery developments, the search for high energy and stable anode materials remains a challenge. Alloy or conversion-typed anode materials are attractive candidates of high specific capacity and low voltage potential, yet their applications are hampered by the large volume expansion and hence poor electrochemical reversibility and fast capacity fade. Here in this paper, we use antimony (Sb) as an example to demonstrate the use of yolk-shell structured anodes for high energy Na-ion batteries. The Sb@C yolk-shell structure prepared by controlled reduction and selective removal of Sb 2O 3 from carbon coated Sb 2O 3 nanoparticlesmore » can accommodate the Sb swelling upon sodiation and improve the structural/electrical integrity against pulverization. It delivers a high specific capacity of ~ 554 mAh g -1, good rate capability (315 mhA g-1 at 10 C rate) and long cyclability (92% capacity retention over 200 cycles). Full-cells of O3-Na 0.9[Cu0.22Fe 0.30Mn 0.48]O 2 cathodes and Sb@C-hard carbon composite anodes demonstrate a high specific energy of ~ 130 Wh kg-1 (based on the total mass of cathode and anode) in the voltage range of 2.0–4.0 V, ~ 1.5 times energy of full-cells with similar design using hard carbon anodes.« less

  20. Green synthesis and characterisation of platinum nanoparticles using quail egg yolk

    NASA Astrophysics Data System (ADS)

    Nadaroglu, Hayrunnisa; Gungor, Azize Alayli; Ince, Selvi; Babagil, Aynur

    2017-02-01

    Nanotechnology is extensively used in all parts today. Therefore, nano synthesis is also significant in all explored areas. The results of studies conducted have revealed that nanoparticle synthesis is performed by using both chemical and physical methods. It is well known that these syntheses are carried out at high charge, pressure and temperature in harsh environments. Therefore, this study investigated green synthesis method that sustains more mild conditions. In this study, quail egg yolk having high vitamin and protein content was prepared for green synthesis reaction and used for the synthesis of platinum nanoparticles in the reaction medium. Reaction situations were optimised as a function of pH, temperature, time and concentration by using quail egg yolk. The results showed that the highest platinum nanoparticles were synthesised at 20 °C and pH 6.0 for 4 h. Also, optimal concentration of metal ions was established as 0.5 mM. The synthesised platinum nanoparticles were characterised by using UV spectrum, X-ray diffraction and scanning electron microscope.

  1. Successful treatment of mixed yolk sac tumor and mature teratoma in the spinal cord: case report.

    PubMed

    Mukasa, Akitake; Yanagisawa, Shunsuke; Saito, Kuniaki; Tanaka, Shota; Takai, Keisuke; Shibahara, Junji; Ikegami, Masachika; Nakao, Yusuke; Takeshita, Katsushi; Matsutani, Masao; Saito, Nobuhito

    2017-03-01

    Primary spinal germ cell tumors are rare, and spinal nongerminomatous germ cell tumors represent an even rarer subset for which no standard therapy has been established. The authors report the case of a 24-year-old woman with multifocal primary spinal germ cell tumors scattered from T-12 to L-5 that consisted of yolk sac tumor and mature teratoma. After diagnostic partial resection, the patient was treated with 30 Gy of craniospinal irradiation and 30 Gy of local spinal irradiation, followed by 8 courses of chemotherapy based on ifosfamide, cisplatin, and etoposide (ICE). Salvage surgery was also performed for residual mature teratoma components after the third course of ICE chemotherapy. Chemotherapy was continued after the operation, but ifosfamide was entirely eliminated from the ICE regimen because severe myelosuppression was observed after previous courses. The patient remains recurrence free as of more than 5 years after the completion of chemotherapy. This case suggests that this treatment strategy is an effective option for primary spinal yolk sac tumor.

  2. Mass spectrometry characterization for N-glycosylation of immunoglobulin Y from hen egg yolk.

    PubMed

    Sheng, Long; He, Zhenjiao; Liu, Yaping; Ma, Meihu; Cai, Zhaoxia

    2018-03-01

    Immunoglobulin Y (IgY) is a new therapeutic antibody that exists in hen egg yolk. It is a glycoprotein, not much is known about its N-glycan structures, site occupancy and site-specific N-glycosylation. In this study, purified protein from hen egg yolk was identified as IgY based on SDS-PAGE and MALDI-TOF/TOF MS. N-glycan was released from IgY using peptide-N4-(N-acetyl-beta-glucosaminyl) asparagine-amidase treatment, and the molecular weight of IgY was calculated using the difference between the molecular weight of IgY and deglycosylated IgY. Two potential N-Glycosylation sites (ASN 308 and ASN 409 ) were detected on IgY by nanoLC-ESI MS. Sugar chains were separated using normal phase liquid chromatography after fluorescence labeling, and 17 N-glycan structures were confirmed using ESI-MS. The sugar chain pattern contained high-mannose oligosaccharide, hybrid oligosaccharide and complex oligosaccharide. These results could lead to other important information regarding IgY glycosylation. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Identification of a major yolk protein as an allergen in sea urchin roe.

    PubMed

    Yamasaki, Ayako; Higaki, Hiromi; Nakashima, Keiko; Yamamoto, Osamu; Hein, Kyaw Zaw; Takahashi, Hitoshi; Chinuki, Yuko; Morita, Eishin

    2010-05-01

    Anaphylaxis after eating sea urchin roe has been reported. However, its major allergens have not yet been identified. The aim of this study was to identify the major allergens of sea urchin roe. Proteins of sea urchin roe were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and two-dimensional electrophoresis (2-DE). An immunoglobulin (Ig)E-binding protein was detected by immunoblotting using the patient's serum. An allergen isolated from 2DE-gel was identified by peptide mass fingerprinting using matrix-assisted laser desorption/ionization-time of flight-mass spectrometry. Immunoblot analysis of sea urchin extracts showed that a 160-kDa protein at pI 6-7 was recognized by the patient's IgE. Peptide mass fingerprint analysis revealed that the protein was the major yolk protein (152 kDa, pI 6.9) of sea urchins. The results show that a major allergen of sea urchin roe is the major yolk protein.

  4. Response surface optimization of pH and ionic strength for emulsion characteristics of egg yolk.

    PubMed

    Kurt, S; Zorba, O

    2009-11-01

    Effects of pH (3.5, 4.5, 6.0, 7.5, and 8.5) and ionic strength (0.05, 0.15, 0.30, 0.45, and 0.55 M NaCl) on emulsion capacity, emulsion stability (ES), apparent yield stress of emulsion (AYS), and emulsion density (ED) of egg yolk were studied by using a model system. Ionic strength and pH had significant (P < 0.01) effects on the emulsion characteristics of egg yolk. Their interaction effects also have been found significant on ES, AYS, and ED. Predicted solutions of ES, emulsion capacity, and ED were minimum. The critical point of ES was determined to be at pH 6.08 and an ionic strength of 0.49 (M NaCl). Predicted solution for AYS was a maximum, which was determined to be at pH 6.04 and an ionic strength of 0.29 (M NaCl). Optimum values of pH and ionic strenght were 4.61 to 7.43 and 0.10 to 0.47, respectively.

  5. Arsanilic acid modified superparamagnetic iron oxide nanoparticles for Purification of alkaline phosphatase from hen's egg yolk.

    PubMed

    Farzi-Khajeh, Hamed; Safa, Kazem D; Dastmalchi, Siavoush

    2017-09-01

    Recent studies of magnetic carrier technology have focused on its applications in separation and purification technologies, due to easy separation of the target from the reaction medium by applying an external magnetic field. In the present study, Fe 3 O 4 superparamagnetic nanoparticles were prepared to utilize a chemical co-precipitation method, then the surfaces of the nanoparticles were modified with arsanilic acid derivatives which were used as the specific nanocarriers for the affinity purification of alkaline phosphatase from the hen's egg yolk. The six different types of magnetic nanocarriers with varied lengths of the linkers were obtained. All samples were characterized step by step and validated using FTIR, SEM, EDX, VSM and XRD analysis methods As the results were shown, the use of inflexible tags with long linkers on the surface of the nanocarrier could lead to better results for separation of alkaline phosphatase from the hen's egg yolk with 76.2% recovery and 1361.7-fold purification. The molecular weight of the purified alkaline phosphatase was estimated to be 68kDa by SDS-PAGE. The results of this study showed that the novel magnetic nanocarriers were capable of purifying alkaline phosphatase in a practically time and cost effective way. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Yolk-shell structured Sb@C anodes for high energy Na-ion batteries

    DOE PAGES

    Song, Junhua; Yan, Pengfei; Luo, Langli; ...

    2017-09-04

    Despite great advances in sodium-ion battery developments, the search for high energy and stable anode materials remains a challenge. Alloy or conversion-typed anode materials are attractive candidates of high specific capacity and low voltage potential, yet their applications are hampered by the large volume expansion and hence poor electrochemical reversibility and fast capacity fade. Here in this paper, we use antimony (Sb) as an example to demonstrate the use of yolk-shell structured anodes for high energy Na-ion batteries. The Sb@C yolk-shell structure prepared by controlled reduction and selective removal of Sb 2O 3 from carbon coated Sb 2O 3 nanoparticlesmore » can accommodate the Sb swelling upon sodiation and improve the structural/electrical integrity against pulverization. It delivers a high specific capacity of ~ 554 mAh g -1, good rate capability (315 mhA g-1 at 10 C rate) and long cyclability (92% capacity retention over 200 cycles). Full-cells of O3-Na 0.9[Cu0.22Fe 0.30Mn 0.48]O 2 cathodes and Sb@C-hard carbon composite anodes demonstrate a high specific energy of ~ 130 Wh kg-1 (based on the total mass of cathode and anode) in the voltage range of 2.0–4.0 V, ~ 1.5 times energy of full-cells with similar design using hard carbon anodes.« less

  7. The anxiolytic activity of n-3 PUFAs enriched egg yolk phospholipids in rat behavioral studies.

    PubMed

    Rutkowska, M; Słupski, W; Trocha, M; Szandruk, M; Rymaszewska, J

    2016-11-02

    Phospholipids play an important role in the biochemical and physiological processes of cells. An association between disturbed phospholipids metabolism in neuronal tissue and anxiety it was shown. The aim of this study was to examine the anxiolytic properties of phospholipids obtained from a new generation of eggs enriched in n-3 PUFA and its effect on locomotor activity in rat behavioral studies N-3 PUFA-enriched egg yolk phospholipids ("super lecithin") were added to the standard feed. Rats were fed by chow without (control group) or with (experimental group) addition of phospholipids. After six weeks of supplementation, the effect of phospholipids on locomotor activity in the open field test and anxiolytic properties in elevated plus maze and Vogel conflict test were examined. In the open field test the total distance traveled in the experimental group was similar to the control group. In the elevated plus maze test a six weeks phospholipids' administration significantly prolonged the time spent on the open arms by rats from experimental group compared to control group. The number of entries into the open arms was also increased but the difference was not statistically significant. The number of punished drinking water in the Vogel conflict test increased significantly in experimental versus control group. The obtained results suggest that the phospholipids isolated from n-3 PUFA enriched egg yolk have a specific anxiolytic effect, without general sedative influence.

  8. Expression and immunolocalisation of the endocytic receptors megalin and cubilin in the human yolk sac and placenta across gestation☆

    PubMed Central

    Burke, K.A.; Jauniaux, E.; Burton, G.J.; Cindrova-Davies, T.

    2013-01-01

    Megalin and cubilin are multifunctional endocytic receptors associated with many transporting epithelia. They play an essential role in transport of nutrients through the visceral yolk sac of rodents during embryogenesis. Here, we immunolocalise them to the endodermal layer of the human yolk sac, and to the syncytiotrophoblast and cytotrophoblast cells of placental villi. In villi, the protein level of both receptors increased with gestation. The mRNA for megalin remained constant, while that encoding cubilin increased with gestation. These results suggest megalin and cubilin may be important in human maternal–fetal transfer, and that they increase across gestation to facilitate this function. PMID:23978537

  9. Zebrafish: an animal model for research in veterinary medicine.

    PubMed

    Nowik, N; Podlasz, P; Jakimiuk, A; Kasica, N; Sienkiewicz, W; Kaleczyc, J

    2015-01-01

    The zebrafish (Danio rerio) has become known as an excellent model organism for studies of vertebrate biology, vertebrate genetics, embryonal development, diseases and drug screening. Nevertheless, there is still lack of detailed reports about usage of the zebrafish as a model in veterinary medicine. Comparing to other vertebrates, they can lay hundreds of eggs at weekly intervals, externally fertilized zebrafish embryos are accessible to observation and manipulation at all stages of their development, which makes possible to simplify the research techniques such as fate mapping, fluorescent tracer time-lapse lineage analysis and single cell transplantation. Although zebrafish are only 2.5 cm long, they are easy to maintain. Intraperitoneal and intracerebroventricular injections, blood sampling and measurement of food intake are possible to be carry out in adult zebrafish. Danio rerio is a useful animal model for neurobiology, developmental biology, drug research, virology, microbiology and genetics. A lot of diseases, for which the zebrafish is a perfect model organism, affect aquatic animals. For a part of them, like those caused by Mycobacterium marinum or Pseudoloma neutrophila, Danio rerio is a natural host, but the zebrafish is also susceptible to the most of fish diseases including Itch, Spring viraemia of carp and Infectious spleen and kidney necrosis. The zebrafish is commonly used in research of bacterial virulence. The zebrafish embryo allows for rapid, non-invasive and real time analysis of bacterial infections in a vertebrate host. Plenty of common pathogens can be examined using zebrafish model: Streptococcus iniae, Vibrio anguillarum or Listeria monocytogenes. The steps are taken to use the zebrafish also in fungal research, especially that dealing with Candida albicans and Cryptococcus neoformans. Although, the zebrafish is used commonly as an animal model to study diseases caused by external agents, it is also useful in studies of metabolic

  10. Functional Characterization of G12, a Gene Required for Mitotic Progression during Gastrulation in Zebrafish

    NASA Technical Reports Server (NTRS)

    Reinsch, Sigrid; Conway, Gregory; Dalton, Bonnie P. (Technical Monitor)

    2002-01-01

    In a differential RNA display screen we have isolated a zebrafish gene, G12, for which homologs can only be found in DNA databases for vertebrates, but not invertebrates. This suggests that this is a gene required specifically in vertebrates. G12 expression is upregulated at mid-blastula transition (MBT). Morpholino inactivation of this gene by injection into 1-cell embryos results in mitotic defects and apoptosis shortly after MBT. Nuclei in morpholino treated embryos also display segregation defects. We have characterized the localization of this gene as a GFP fusion in live and fixed embryos. Overexpression of G12-GFP is non-toxic. Animals retain GFP expression for at least 7 days with no developmental defects, Interestingly in these animals G12-GFP is never detectable in blood cells though blood is present. In the deep cells of early embryos, G 12GFP is localized to nuclei and cytoskeletal elements in interphase and to the centrosome and spindle apparatus during mitosis. In the EVL, G12-GFP shows additional localization to the cell periphery, especially in mitosis. In the yolk syncytium, G12-GFP again localizes to nuclei and strongly to cytoplasmic microtubules of migrating nuclei at the YSL margin. Morpholinc, injection specifically into the YSL after cellularization blocks epiboly and nuclei of the YSL show mitotic defects while deep cells show no mitotic defects and continue to divide. Rescue experiments in which morpholino and G12-GFP RNA are co-injected indicate partial rescue by the G12-GFP. The rescue is cell autonomous; that is, regions of the embryo with higher G12-GFP expression show fewer mitotic defects. Spot 14, the human bomolog of G12, has been shown to be amplified in aggressive breast tumors. This finding, along with our functional and morphological data suggest that G12 and spot 14 are vertebrate-specific and may function either as mitotic checkpoints or as structural components of the spindle apparatus.

  11. Comparisons among serum, egg albumin and yolk concentrations of corticosterone as biomarkers of basal and stimulated adrenocortical activity of laying hens.

    PubMed

    Cook, N J; Renema, R; Wilkinson, C; Schaefer, A L

    2009-09-01

    1. Serial blood samples from individual birds were analysed for corticosterone concentrations under basal and stimulated conditions, and matched to eggs from the same birds for comparison to albumin and yolk concentrations of corticosterone. 2. Serum corticosterone exhibited increases in response to stimulation by ACTH and Handling stress. There were no significant increases in egg albumin or yolk concentrations of corticosterone following stimulation. 3. Several significant correlations were observed between the mean and area under the curve (AUC) measurements of serum corticosterone concentrations with albumin and yolk corticosterone concentrations in eggs laid from 1 to 2 d later. 4. The results demonstrated a relationship between endogenous concentrations of serum corticosterone that reflected daily adrenocortical output with albumin and yolk corticosterone concentrations in eggs laid the following day. 5. The results do not support the concept of albumin and yolk concentrations of corticosterone as biomarkers of acute adrenocortical responses to stimulation.

  12. The zebrafish bozozok locus encodes Dharma, a homeodomain protein essential for induction of gastrula organizer and dorsoanterior embryonic structures.

    PubMed

    Fekany, K; Yamanaka, Y; Leung, T; Sirotkin, H I; Topczewski, J; Gates, M A; Hibi, M; Renucci, A; Stemple, D; Radbill, A; Schier, A F; Driever, W; Hirano, T; Talbot, W S; Solnica-Krezel, L

    1999-04-01

    The dorsal gastrula organizer plays a fundamental role in establishment of the vertebrate axis. We demonstrate that the zebrafish bozozok (boz) locus is required at the blastula stages for formation of the embryonic shield, the equivalent of the gastrula organizer and expression of multiple organizer-specific genes. Furthermore, boz is essential for specification of dorsoanterior embryonic structures, including notochord, prechordal mesendoderm, floor plate and forebrain. We report that boz mutations disrupt the homeobox gene dharma. Overexpression of boz in the extraembryonic yolk syncytial layer of boz mutant embryos is sufficient for normal development of the overlying blastoderm, revealing an involvement of extraembryonic structures in anterior patterning in fish similarly to murine embryos. Epistatic analyses indicate that boz acts downstream of beta-catenin and upstream to TGF-beta signaling or in a parallel pathway. These studies provide genetic evidence for an essential function of a homeodomain protein in beta-catenin-mediated induction of the dorsal gastrula organizer and place boz at the top of a hierarchy of zygotic genes specifying the dorsal midline of a vertebrate embryo.

  13. Immunostaining of dissected zebrafish embryonic heart.

    PubMed

    Yang, Jingchun; Xu, Xiaolei

    2012-01-10

    Zebrafish embryo becomes a popular in vivo vertebrate model for studying cardiac development and human heart diseases due to its advantageous embryology and genetics. About 100-200 embryos are readily available every week from a single pair of adult fish. The transparent embryos that develop ex utero make them ideal for assessing cardiac defects. The expression of any gene can be manipulated via morpholino technology or RNA injection. Moreover, forward genetic screens have already generated a list of mutants that affect different perspectives of cardiogenesis. Whole mount immunostaining is an important technique in this animal model to reveal the expression pattern of the targeted protein to a particular tissue. However, high resolution images that can reveal cellular or subcellular structures have been difficult, mainly due to the physical location of the heart and the poor penetration of the antibodies. Here, we present a method to address these bottlenecks by dissecting heart first and then conducting the staining process on the surface of a microscope slide. To prevent the loss of small heart samples and to facilitate solution handling, we restricted the heart samples within a circle on the surface of the microscope slides drawn by an immEdge pen. After the staining, the fluorescence signals can be directly observed by a compound microscope. Our new method significantly improves the penetration for antibodies, since a heart from an embryonic fish only consists of few cell layers. High quality images from intact hearts can be obtained within a much reduced procession time for zebrafish embryos aged from day 2 to day 6. Our method can be potentially extended to stain other organs dissected from either zebrafish or other small animals. Copyright © 2012 Journal of Visualized Experiments

  14. GROWTH AND BEHAVIOR OF LARVAL ZEBRAFISH Danio ...

    EPA Pesticide Factsheets

    Because Zebrafish (Danio rerio) have become a popular and important model for scientific research, the capability to rear larval zebrafish to adulthood is of great importance. Recently research examining the effects of diet (live versus processed) have been published. In the current study we examined whether the larvae can be reared on a processed diet alone, live food alone, or the combination while maintaining normal locomotor behavior, and acceptable survival, length and weight at 14 dpf in a static system. A 14 day feeding trial was conducted in glass crystallizing dishes containing 500 ml of 4 ppt Instant Ocean. On day 0 pdf 450 embryos were selected as potential study subjects and placed in a 26○C incubator on a 14:10 (light:dark) light cycle. At 4 dpf 120 normally developing embryos were selected per treatment and divided into 3 bowls of 40 embryos (for an n=3 per treatment; 9 bowls total). Treatment groups were: G (Gemma Micro 75 only), R (L-type marine rotifers (Brachionus plicatilis) only) or B (Gemma and rotifers). Growth (length), survival, water quality and rotifer density were monitored on days 5-14. On day 14, weight of larva in each bowl was measured and 8 larva per bowl were selected for use in locomotor testing. This behavior paradigm tests individual larval zebrafish under both light and dark conditions in a 24-well plate.After 14 dpf, survival among the groups was not different (92-98%). By days 7 -14 R and B larvae were ~2X longer

  15. Cholinergic innervation of the zebrafish olfactory bulb.

    PubMed

    Edwards, Jeffrey G; Greig, Ann; Sakata, Yoko; Elkin, Dimitry; Michel, William C

    2007-10-20

    A number of fish species receive forebrain cholinergic input but two recent reports failed to find evidence of cholinergic cell bodies or fibers in the olfactory bulbs (OBs) of zebrafish. In the current study we sought to confirm these findings by examining the OBs of adult zebrafish for choline acetyltransferase (ChAT) immunoreactivity. We observed a diffuse network of varicose ChAT-positive fibers associated with the nervus terminalis ganglion innervating the mitral cell/glomerular layer (MC/GL). The highest density of these fibers occurred in the anterior region of the bulb. The cellular targets of this cholinergic input were identified by exposing isolated OBs to acetylcholine receptor (AChR) agonists in the presence of agmatine (AGB), a cationic probe that permeates some active ion channels. Nicotine (50 microM) significantly increased the activity-dependent labeling of mitral cells and juxtaglomerular cells but not of tyrosine hydroxlase-positive dopaminergic neurons (TH(+) cells) compared to control preparations. The nAChR antagonist mecamylamine, an alpha7-nAChR subunit-specific antagonist, calcium-free artificial cerebrospinal fluid, or a cocktail of ionotropic glutamate receptor (iGluR) antagonists each blocked nicotine-stimulated labeling, suggesting that AGB does not enter the labeled neurons through activated nAChRs but rather through activated iGluRs following ACh-stimulated glutamate release. Deafferentation of OBs did not eliminate nicotine-stimulated labeling, suggesting that cholinergic input is primarily acting on bulbar neurons. These findings confirm the presence of a functioning cholinergic system in the zebrafish OB.

  16. Novel biomarkers of perchlorate exposure in zebrafish

    Mukhi, S.; Carr, J.A.; Anderson, T.A.; Patino, R.

    2005-01-01

    Perchlorate inhibits iodide uptake by thyroid follicles and lowers thyroid hormone production. Although several effects of perchlorate on the thyroid system have been reported, the utility of these pathologies as markers of environmental perchlorate exposures has not been adequately assessed. The present study examined time-course and concentration-dependent effects of perchlorate on thyroid follicle hypertrophy, colloid depletion, and angiogenesis; alterations in whole-body thyroxine (T4) levels; and somatic growth and condition factor of subadult and adult zebrafish. Changes in the intensity of the colloidal T4 ring previously observed in zebrafish also were examined immunohistochemically. Three-month-old zebrafish were exposed to ammonium perchlorate at measured perchlorate concentrations of 0, 11, 90, 1,131, and 11,480 ppb for 12 weeks and allowed to recover in clean water for 12 weeks. At two weeks of exposure, the lowest-observed-effective concentrations (LOECs) of perchlorate that induced angiogenesis and depressed the intensity of colloidal T4 ring were 90 and 1,131 ppb, respectively; other parameters were not affected (whole-body T4 was not determined at this time). At 12 weeks of exposure, LOECs for colloid depletion, hypertrophy, angiogenesis, and colloidal T4 ring were 11,480, 1,131, 90, and 11 ppb, respectively. All changes were reversible, but residual effects on angiogenesis and colloidal T4 ring intensity were still present after 12 weeks of recovery (LOEC, 11,480 ppb). Whole-body T 4 concentration, body growth (length and weight), and condition factor were not affected by perchlorate. The sensitivity and longevity of changes in colloidal T4 ring intensity and angiogenesis suggest their usefulness as novel markers of perchlorate exposure. The 12-week LOEC for colloidal T4 ring is the lowest reported for any perchlorate biomarker in aquatic vertebrates. ?? 2005 SETAC.

  17. Learning and memory in zebrafish (Danio rerio).

    PubMed

    Gerlai, R

    2016-01-01

    Learning and memory are defining features of our own species inherently important to our daily lives and to who we are. Without our memories we cease to exist as a person. Without our ability to learn individuals and collectively our society would cease to function. Diseases of the mind still remain incurable. The interest in understanding of the mechanisms of learning and memory is thus well founded. Given the complexity of such mechanisms, concerted efforts have been made to study them under controlled laboratory conditions, ie, with laboratory model organisms. The zebrafish, although new in this field, is one such model organism. The rapidly developing forward- and reverse genetic methods designed for the zebrafish and the increasing use of pharmacological tools along with numerous neurobiology techniques make this species perhaps the best model for the analysis of the mechanisms of complex central nervous system characteristics. The fact that it is an evolutionarily ancient and simpler vertebrate, but at the same time it possesses numerous conserved features across multiple levels of biological organization makes this species an excellent tool for the analysis of the mechanisms of learning and memory. The bottleneck lies in our understanding of its cognitive and mnemonic features, the topic of this chapter. The current paper builds on a chapter published in the previous edition and continues to focus on associative learning, but now it extends the discussion to other forms of learning and to recent discoveries on memory-related features and findings obtained both in adults and larval zebrafish. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Adaptive Locomotor Behavior in Larval Zebrafish

    PubMed Central

    Portugues, Ruben; Engert, Florian

    2011-01-01

    In this study we report that larval zebrafish display adaptive locomotor output that can be driven by unexpected visual feedback. We develop a new assay that addresses visuomotor integration in restrained larval zebrafish. The assay involves a closed-loop environment in which the visual feedback a larva receives depends on its own motor output in a way that resembles freely swimming conditions. The experimenter can control the gain of this closed feedback loop, so that following a given motor output the larva experiences more or less visual feedback depending on whether the gain is high or low. We show that increases and decreases in this gain setting result in adaptive changes in behavior that lead to a generalized decrease or increase of motor output, respectively. Our behavioral analysis shows that both the duration and tail beat frequency of individual swim bouts can be modified, as well as the frequency with which bouts are elicited. These changes can be implemented rapidly, following an exposure to a new gain of just 175 ms. In addition, modifications in some behavioral parameters accumulate over tens of seconds and effects last for at least 30 s from trial to trial. These results suggest that larvae establish an internal representation of the visual feedback expected from a given motor output and that the behavioral modifications are driven by an error signal that arises from the discrepancy between this expectation and the actual visual feedback. The assay we develop presents a unique possibility for studying visuomotor integration using imaging techniques available in the larval zebrafish. PMID:21909325

  19. Adaptive locomotor behavior in larval zebrafish.

    PubMed

    Portugues, Ruben; Engert, Florian

    2011-01-01

    In this study we report that larval zebrafish display adaptive locomotor output that can be driven by unexpected visual feedback. We develop a new assay that addresses visuomotor integration in restrained larval zebrafish. The assay involves a closed-loop environment in which the visual feedback a larva receives depends on its own motor output in a way that resembles freely swimming conditions. The experimenter can control the gain of this closed feedback loop, so that following a given motor output the larva experiences more or less visual feedback depending on whether the gain is high or low. We show that increases and decreases in this gain setting result in adaptive changes in behavior that lead to a generalized decrease or increase of motor output, respectively. Our behavioral analysis shows that both the duration and tail beat frequency of individual swim bouts can be modified, as well as the frequency with which bouts are elicited. These changes can be implemented rapidly, following an exposure to a new gain of just 175 ms. In addition, modifications in some behavioral parameters accumulate over tens of seconds and effects last for at least 30 s from trial to trial. These results suggest that larvae establish an internal representation of the visual feedback expected from a given motor output and that the behavioral modifications are driven by an error signal that arises from the discrepancy between this expectation and the actual visual feedback. The assay we develop presents a unique possibility for studying visuomotor integration using imaging techniques available in the larval zebrafish.

  20. Toxicity of chlorine to zebrafish embryos

    PubMed Central

    Kent, Michael L.; Buchner, Cari; Barton, Carrie; Tanguay, Robert L.

    2014-01-01

    Surface disinfection of fertilized fish eggs is widely used in aquaculture to reduce extraovum pathogens that may be released from brood fish during spawning, and this is routinely used in zebrafish (Danio rerio) research laboratories. Most laboratories use approximately 25 – 50 ppm unbuffered chlorine solution for 5 – 10 min. Treatment of embryos with chlorine has significant germicidal effects for many Gram-negative bacteria, viruses, and trophozoite stages of protozoa, it has reduced efficacy against cyst or spore stages of protozoa and certain Mycobacterium spp. Therefore, we evaluated the toxicity of unbufferred and buffered chlorine solution to embryos exposed at 6 or 24 hours post-fertilization (hpf) to determine if higher concentrations can be used for treating zebrafish embryos. Most of our experiments entailed using an outbred line (5D), with both mortality and malformations as endpoints. We found that 6 hpf embryos consistently were more resistant than 24 hpf embryos to the toxic effects of chlorine. Chlorine is more toxic and germicidal at lower pHs, and chlorine causes elevated pH. Consistent with this, we found that unbufferred chlorine solutions (pH ca 8–9) were less toxic at corresponding concentrations than solutions buffered to pH 7. Based on our findings here, we recommend treating 6 hpf embryos for 10 min and 24 hpf for 5 min with unbuffered chlorine solution at 100 ppm. One trial indicated that AB fish, a popular outbred line, are more susceptible to toxicity than 5Ds. This suggests that variability between zebrafish lines occurs, and researchers should evaluate each line or strain under their particular laboratory conditions for selection of the optimum chlorine treatment procedure. PMID:24429474

  1. Zebrafish: A Versatile Animal Model for Fertility Research.

    PubMed

    Hoo, Jing Ying; Kumari, Yatinesh; Shaikh, Mohd Farooq; Hue, Seow Mun; Goh, Bey Hing

    2016-01-01

    The utilization of zebrafish in biomedical research is very common in the research world nowadays. Today, it has emerged as a favored vertebrate organism for the research in science of reproduction. There is a significant growth in amount numbers of scientific literature pertaining to research discoveries in reproductive sciences in zebrafish. It has implied the importance of zebrafish in this particular field of research. In essence, the current available literature has covered from the very specific brain region or neurons of zebrafish, which are responsible for reproductive regulation, until the gonadal level of the animal. The discoveries and findings have proven that this small animal is sharing a very close/similar reproductive system with mammals. More interestingly, the behavioral characteristics and along with the establishment of animal courtship behavior categorization in zebrafish have laid an even stronger foundation and firmer reason on the suitability of zebrafish utilization in research of reproductive sciences. In view of the immense importance of this small animal for the development of reproductive sciences, this review aimed at compiling and describing the proximate close similarity of reproductive regulation on zebrafish and human along with factors contributing to the infertility, showing its versatility and its potential usage for fertility research.

  2. Effectiveness of recommended euthanasia methods in larval zebrafish (Danio rerio).

    PubMed

    Strykowski, Jennifer L; Schech, Joseph M

    2015-01-01

    The popularity of zebrafish and its use as a model organism in biomedical research including genetics, development, and toxicology, has increased over the past 20 y and continues to grow. However, guidelines for euthanasia remain vague, and the responsibility of creating appropriate euthanasia protocols essentially falls on individual facilities. To reduce variation in experimental results among labs, a standard method of euthanasia for zebrafish would be useful. Although various euthanasia methods have been compared, few studies focus on the effectiveness of euthanasia methods for larval zebrafish. In this study, we exposed larval zebrafish to each of 3 euthanasia agents (MS222, eugenol, and hypothermic shock) and assessed the recovery rate. Hypothermic shock appeared to be the most effective method for euthanizing zebrafish at 14 d after fertilization; however, this method may not be considered an efficient method for large numbers of larval zebrafish. Exposure to chemicals, such as MS222 and eugenol, were ineffective methods for euthanasia at this stage of development. When these agents are used, secondary measures should be taken to ensure death. Choosing a euthanasia method that is effective, efficient, and humane can be challenging. Determining a method of euthanasia that is suitable for fish of all stages will bring the zebrafish community closer to meeting this challenge.

  3. Effectiveness of Recommended Euthanasia Methods in Larval Zebrafish (Danio rerio)

    PubMed Central

    Strykowski, Jennifer L; Schech, Joseph M

    2015-01-01

    The popularity of zebrafish and its use as a model organism in biomedical research including genetics, development, and toxicology, has increased over the past 20 y and continues to grow. However, guidelines for euthanasia remain vague, and the responsibility of creating appropriate euthanasia protocols essentially falls on individual facilities. To reduce variation in experimental results among labs, a standard method of euthanasia for zebrafish would be useful. Although various euthanasia methods have been compared, few studies focus on the effectiveness of euthanasia methods for larval zebrafish. In this study, we exposed larval zebrafish to each of 3 euthanasia agents (MS222, eugenol, and hypothermic shock) and assessed the recovery rate. Hypothermic shock appeared to be the most effective method for euthanizing zebrafish at 14 d after fertilization; however, this method may not be considered an efficient method for large numbers of larval zebrafish. Exposure to chemicals, such as MS222 and eugenol, were ineffective methods for euthanasia at this stage of development. When these agents are used, secondary measures should be taken to ensure death. Choosing a euthanasia method that is effective, efficient, and humane can be challenging. Determining a method of euthanasia that is suitable for fish of all stages will bring the zebrafish community closer to meeting this challenge. PMID:25651096

  4. The zebrafish world of colors and shapes: preference and discrimination.

    PubMed

    Oliveira, Jessica; Silveira, Mayara; Chacon, Diana; Luchiari, Ana

    2015-04-01

    Natural environment imposes many challenges to animals, which have to use cognitive abilities to cope with and exploit it to enhance their fitness. Since zebrafish is a well-established model for cognitive studies and high-throughput screening for drugs and diseases that affect cognition, we tested their ability for ambient color preference and 3D objects discrimination to establish a protocol for memory evaluation. For the color preference test, zebrafish were observed in a multiple-chamber tank with different environmental color options. Zebrafish showed preference for blue and green, and avoided yellow and red. For the 3D objects discrimination, zebrafish were allowed to explore two equal objects and then observed in a one-trial test in which a new color, size, or shape of the object was presented. Zebrafish showed discrimination for color, shape, and color+shape combined, but not size. These results imply that zebrafish seem to use some categorical system to discriminate items, and distracters affect their ability for discrimination. The type of variables available (color and shape) may favor zebrafish objects perception and facilitate discrimination processing. We suggest that this easy and simple memory test could serve as a useful screening tool for cognitive dysfunction and neurotoxicological studies.

  5. Designing and Testing of Self-Cleaning Recirculating Zebrafish Tanks.

    PubMed

    Nema, Shubham; Bhargava, Yogesh

    2016-08-01

    Maintenance of large number of zebrafish in captive conditions is a daunting task. This can be eased by the use of recirculating racks with self-cleaning zebrafish tanks. Commercially available systems are costly, and compatibility of intercompany products has never been investigated. Although various cost-effective designs and methods of construction of custom-made recirculating zebrafish racks are available in literature, the design of self-cleaning zebrafish tanks is still not available. In this study, we report the design and method of construction of the self-cleaning unit, which can be fitted in any zebrafish tank. We validated the design by investigating sediment cleaning process in rectangular and cylindrical tank geometries using time lapse imaging. Our results suggest that for both tank geometries, the tanks fitted with self-cleaning unit provided superior sediment cleaning than the tanks fitted with overflow-drain unit. Although the self-cleaning unit could clean the sediment completely from both geometries over prolonged period, the cleaning of sediments was faster in the cylindrical tank than the rectangular tank. In conclusion, cost and efforts of zebrafish maintenance could be significantly reduced through the installation of our self-cleaning unit in any custom-made zebrafish tank.

  6. An assay for lateral line regeneration in adult zebrafish.

    PubMed

    Pisano, Gina C; Mason, Samantha M; Dhliwayo, Nyembezi; Intine, Robert V; Sarras, Michael P

    2014-04-08

    Due to the clinical importance of hearing and balance disorders in man, model organisms such as the zebrafish have been used to study lateral line development and regeneration. The zebrafish is particularly attractive for such studies because of its rapid development time and its high regenerative capacity. To date, zebrafish studies of lateral line regeneration have mainly utilized fish of the embryonic and larval stages because of the lower number of neuromasts at these stages. This has made quantitative analysis of lateral line regeneration/and or development easier in the earlier developmental stages. Because many zebrafish models of neurological and non-neurological diseases are studied in the adult fish and not in the embryo/larvae, we focused on developing a quantitative lateral line regenerative assay in adult zebrafish so that an assay was available that could be applied to current adult zebrafish disease models. Building on previous studies by Van Trump et al. that described procedures for ablation of hair cells in adult Mexican blind cave fish and zebrafish (Danio rerio), our assay was designed to allow quantitative comparison between control and experimental groups. This was accomplished by developing a regenerative neuromast standard curve based on the percent of neuromast reappearance over a 24 hr time period following gentamicin-induced necrosis of hair cells in a defined region of the lateral line. The assay was also designed to allow extension of the analysis to the individual hair cell level when a higher level of resolution is required.

  7. Computerized image analysis for quantitative neuronal phenotyping in zebrafish.

    PubMed

    Liu, Tianming; Lu, Jianfeng; Wang, Ye; Campbell, William A; Huang, Ling; Zhu, Jinmin; Xia, Weiming; Wong, Stephen T C

    2006-06-15

    An integrated microscope image analysis pipeline is developed for automatic analysis and quantification of phenotypes in zebrafish with altered expression of Alzheimer's disease (AD)-linked genes. We hypothesize that a slight impairment of neuronal integrity in a large number of zebrafish carrying the mutant genotype can be detected through the computerized image analysis method. Key functionalities of our zebrafish image processing pipeline include quantification of neuron loss in zebrafish embryos due to knockdown of AD-linked genes, automatic detection of defective somites, and quantitative measurement of gene expression levels in zebrafish with altered expression of AD-linked genes or treatment with a chemical compound. These quantitative measurements enable the archival of analyzed results and relevant meta-data. The structured database is organized for statistical analysis and data modeling to better understand neuronal integrity and phenotypic changes of zebrafish under different perturbations. Our results show that the computerized analysis is comparable to manual counting with equivalent accuracy and improved efficacy and consistency. Development of such an automated data analysis pipeline represents a significant step forward to achieve accurate and reproducible quantification of neuronal phenotypes in large scale or high-throughput zebrafish imaging studies.

  8. Making Waves: New Developments in Toxicology With the Zebrafish.

    PubMed

    Horzmann, Katharine A; Freeman, Jennifer L

    2018-05-01

    The laboratory zebrafish (Danio rerio) is now an accepted model in toxicologic research. The zebrafish model fills a niche between in vitro models and mammalian biomedical models. The developmental characteristics of the small fish are strategically being used by scientists to study topics ranging from high-throughput toxicity screens to toxicity in multi- and transgenerational studies. High-throughput technology has increased the utility of zebrafish embryonic toxicity assays in screening of chemicals and drugs for toxicity or effect. Additionally, advances in behavioral characterization and experimental methodology allow for observation of recognizable phenotypic changes after xenobiotic exposure. Future directions in zebrafish research are predicted to take advantage of CRISPR-Cas9 genome editing methods in creating models of disease and interrogating mechanisms of action with fluorescent reporters or tagged proteins. Zebrafish can also model developmental origins of health and disease and multi- and transgenerational toxicity. The zebrafish has many advantages as a toxicologic model and new methodologies and areas of study continue to expand the usefulness and application of the zebrafish.

  9. Zebrafish xenograft models of cancer and metastasis for drug discovery.

    PubMed

    Brown, Hannah K; Schiavone, Kristina; Tazzyman, Simon; Heymann, Dominique; Chico, Timothy Ja

    2017-04-01

    Patients with metastatic cancer suffer the highest rate of cancer-related death, but existing animal models of metastasis have disadvantages that limit our ability to understand this process. The zebrafish is increasingly used for cancer modelling, particularly xenografting of human cancer cell lines, and drug discovery, and may provide novel scientific and therapeutic insights. However, this model system remains underexploited. Areas covered: The authors discuss the advantages and disadvantages of the zebrafish xenograft model for the study of cancer, metastasis and drug discovery. They summarise previous work investigating the metastatic cascade, such as tumour-induced angiogenesis, intravasation, extravasation, dissemination and homing, invasion at secondary sites, assessing metastatic potential and evaluation of cancer stem cells in zebrafish. Expert opinion: The practical advantages of zebrafish for basic biological study and drug discovery are indisputable. However, their ability to sufficiently reproduce and predict the behaviour of human cancer and metastasis remains unproven. For this to be resolved, novel mechanisms must to be discovered in zebrafish that are subsequently validated in humans, and for therapeutic interventions that modulate cancer favourably in zebrafish to successfully translate to human clinical studies. In the meantime, more work is required to establish the most informative methods in zebrafish.

  10. Zebrafish: A Versatile Animal Model for Fertility Research

    PubMed Central

    Hoo, Jing Ying; Kumari, Yatinesh; Shaikh, Mohd Farooq; Hue, Seow Mun

    2016-01-01

    The utilization of zebrafish in biomedical research is very common in the research world nowadays. Today, it has emerged as a favored vertebrate organism for the research in science of reproduction. There is a significant growth in amount numbers of scientific literature pertaining to research discoveries in reproductive sciences in zebrafish. It has implied the importance of zebrafish in this particular field of research. In essence, the current available literature has covered from the very specific brain region or neurons of zebrafish, which are responsible for reproductive regulation, until the gonadal level of the animal. The discoveries and findings have proven that this small animal is sharing a very close/similar reproductive system with mammals. More interestingly, the behavioral characteristics and along with the establishment of animal courtship behavior categorization in zebrafish have laid an even stronger foundation and firmer reason on the suitability of zebrafish utilization in research of reproductive sciences. In view of the immense importance of this small animal for the development of reproductive sciences, this review aimed at compiling and describing the proximate close similarity of reproductive regulation on zebrafish and human along with factors contributing to the infertility, showing its versatility and its potential usage for fertility research. PMID:27556045

  11. Functional Analysis of Nuclear Estrogen Receptors in Zebrafish Reproduction by Genome Editing Approach.

    PubMed

    Lu, Huijie; Cui, Yong; Jiang, Liwen; Ge, Wei

    2017-07-01

    Estrogens signal through both nuclear and membrane receptors with most reported effects being mediated via the nuclear estrogen receptors (nERs). Although much work has been reported on nERs in the zebrafish, there is a lack of direct genetic evidence for their functional roles and importance in reproduction. To address this issue, we undertook this study to disrupt all three nERs in the zebrafish, namely esr1 (ERα), esr2a (ERβII), and esr2b (ERβI), by the genome-editing technology clustered regularly interspaced short palindromic repeats and its associated nuclease (CRISPR/Cas9). Using this loss-of-function genetic approach, we successfully created three mutant zebrafish lines with each nER knocked out. In addition, we also generated all possible double and triple knockouts of the three nERs. The phenotypes of these mutants in reproduction were analyzed in all single, double, and triple nER knockouts in both females and males. Surprisingly, all three single nER mutant fish lines display normal reproductive development and function in both females and males, suggesting functional redundancy among these nERs. Further analysis of double and triple knockouts showed that nERs, especially Esr2a and Esr2b, were essential for female reproduction, and loss of these two nERs led to an arrest of folliculogenesis at previtellogenic stage II followed by sex reversal from female to male. In addition, the current study also revealed a unique role for Esr2a in follicle cell proliferation and transdifferentiation, follicle growth, and chorion formation. Taken together, this study provides the most comprehensive genetic analysis for differential functions of esr1, esr2a, and esr2b in fish reproduction. Copyright © 2017 Endocrine Society.

  12. Transgene manipulation in zebrafish by using recombinases.

    PubMed

    Dong, Jie; Stuart, Gary W

    2004-01-01

    Although much remains to be done, our results to date suggest that efficient and precise genome engineering in zebrafish will be possible in the future by using Cre recombinase and SB transposase in combination with their respective target sites. In this study, we provide the first evidence that Cre recombinase can mediate effective site-specific deletion of transgenes in zebrafish. We found that the efficiency of target site utilization could approach 100%, independent of whether the target site was provided transiently by injection or stably within an integrated transgene. Microinjection of Cre mRNA appeared to be slightly more effective for this purpose than microinjection of Cre-expressing plasmid DNA. Our work has not yet progressed to the point where SB-mediated mobilization of our transgene constructs would be observed. However, a recent report has demonstrated that SB can enhance transgenesis rates sixfold over conventional methods by efficiently mediating multiple single-copy insertion of transgenes into the zebrafish genome (Davidson et al., 2003). Therefore, it seems likely that a combined system should eventually allow both SB-mediated transgene mobilization and Cre-mediated transgene modification. Our goal is to validate methods for the precise reengineering of the zebrafish genome by using a combination of Cre-loxP and SB transposon systems. These methods can be used to delete, replace, or mobilize large pieces of DNA or to modify the genome only when and where required by the investigator. For example, it should be possible to deliver particular RNAi genes to well-expressed chromosomal loci and then exchange them easily with alternative RNAi genes for the specific suppression of alternative targets. As a nonviral vector for gene therapy, the transposon component allows for the possibility of highly efficient integration, whereas the Cre-loxP component can target the integration and/or exchange of foreign DNA into specific sites within the genome. The

  13. Larval rearing of zebrafish at suboptimal temperatures.

    PubMed

    Delomas, Thomas A; Dabrowski, Konrad

    2018-05-01

    Temperature-sensitive mutants have been widely utilized in single-cell and invertebrate model systems, particularly to study the function of essential genes. Few temperature-sensitive mutants have been identified in zebrafish, likely due to the difficulty of raising zebrafish at low temperatures. We describe a novel rearing protocol that allows rapid growth of larval and juvenile zebrafish at 23 °C compared to previous data in the literature. Embryos collected from four breeding pairs were maintained at 28.5 ± 0.5 °C until 5 days post-fertilization (dpf) - the onset of exogenous feeding. Larvae were then divided to six tanks and three tanks were cooled to 23 ± 0.2 °C. Fish were fed a live diet (marine rotifers Brachionus plicatilis and Artemia nauplii) and maintained under a set of environmental parameters shown to increase growth rate: continuous light, low salinity (3ppt), and algal turbidity. Mean total length and weight of fish at 21dpf were 12.7 ± 0.3 mm and 20.5 ± 1.5 mg for the 23 °C treatment and 18.5 ± 0.4 mm and 67.3 ± 3.4 mg for the 28.5 °C control. By 35 dpf, the fish raised at 23 °C had reached a mean length and weight of 18.9 ± 0.7 mm and 76.4 ± 6.7 mg, approximately the size control fish reached at 21 dpf. At 35 dpf, water temperature was raised to 28 °C and fish were reared to maturity (75 dpf) under standard conditions (freshwater, 13 L:11D photoperiod, dry diet, no added algal turbidity). Sex ratio and fertility were assessed and compared between temperature groups. There were no significant differences in sex ratio, fertilization rate, embryo viability at 1 dpf, clutch size, or relative fecundity. This rearing protocol will allow for efficient utilization of temperature-sensitive mutations in the zebrafish model system. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Zebrafish scarb2a insertional mutant reveals a novel function for the Scarb2/Limp2 receptor in notochord development.

    PubMed

    Diaz-Tellez, Abigail; Zampedri, Cecilia; Ramos-Balderas, Jose L; García-Hernández, Fernando; Maldonado, Ernesto

    2016-04-01

    Scarb2 or Limp2 belong to a subfamily of Scavenger receptors described as lysosomal transmembrane glycosylated receptors, that are mutated in the human syndrome AMRF (action myoclonus-renal failure). The zebrafish insertional mutant scarb2a(hi1463Tg) has notochord defects, the notochord is a defining feature of chordates running along the center of the longitudinal axis and it is essential for forming the spinal column in all vertebrates. There are three paralogous scarb2 genes in zebrafish; scarb2a, scarb2b, and scarb2c. Both Scarb2a and Scarb2b proteins lack the classical di-leucine motif. We found that scarb2a(hi1463Tg) homozygous zebrafish embryos have a null mutation impairing vacuole formation in the notochord and simultaneously disrupting proper formation of the basement membrane resulting in its thickening at the ventral side of the notochord, which may be the cause for the anomalous upward bending observed in the trunk. Through whole-mount in situ hybridization, we detected scarb2a mRNA expression in the notochord and in the brain early in development. However, it is puzzling that scarb2a notochord mRNA expression is short-lived in the presumptive notochord and precedes the complete differentiation of the notochord. This work describes a novel function for the Scarb2 receptor as an essential glycoprotein for notochord development. © 2016 Wiley Periodicals, Inc.

  15. Influence of soy oil source and dietary supplementation of vitamins E and C on the oxidation status of serum and egg yolk, and the lipid profile of egg yolk.

    PubMed

    Irandoust, H; Ahn, D U

    2015-11-01

    An experiment was conducted to determine the effects of adding vitamins E and C to diets containing 3.5% refined soy oil (SO), recycled soy oil (RSO), or acidulated soy oil soapstocks (ASS) on 1) fatty acid (FA) profile, and cholesterol, triglyceride (TG) and α-tocopherol (α-T) concentrations of yolk, and 2) the oxidation status of serum and yolk. Twelve dietary treatments, using 3 oil sources, 2 levels of vitamin E (0 vs. 250 mg/kg), and 2 levels of vitamin C (0 vs. 250 mg/kg), were prepared. A total of 300 W36 Hy-line laying hens, from 44 to 56 weeks of age, were placed in 60 cages (5 birds/cage) and 5 cages were randomly assigned to one of the 12 diets. Blood samples and eggs were collected after 84 d on trial. No interactions among main effects were found for any of the traits studied. Oil sources had little effects on the FA profile of the yolk, except for C18:3 that was higher (P-value of < 0.01) in the hens fed SO than those fed RSO or ASS. Vitamin E supplementation significantly (P-value of < 0.05) increased the concentration of C16:0, C18:0, and C16:1 but decreased that of C18:2 and C22:6n3 in the yolk. Vitamin C supplementation significantly (P-value of < 0.05) increased C18:0 and C18:3 concentrations in the yolk but decreased the n6 to n3 FA ratio. The concentrations of cholesterol and triglyceride in serum and yolk were not affected by dietary treatment but α-tocopherol concentration increased (P-value of < 0.01) by the dietary vitamin E. Compared with the hens fed the SO diets, malondialdehyde (MDA) concentration in serum was higher with RSO diet but lower with ASS diet. Vitamin E and vitamin C supplementation decreased (P-value of < 0.05) serum MDA. Yolk FA profile was affected not only by the FA profile of the oil source used in diet, but also by the supplementation of vitamin E and C. The results showed that triglyceride profile, but not cholesterol content, of egg was affected by fatty acid profile of the supplemental oil and the vitamin C and E

  16. Identification of oocyte progenitor cells in the zebrafish ovary.

    PubMed

    Draper, Bruce W

    2012-01-01

    Zebrafish breed year round and females are capable of producing thousands of eggs during their lifetime. This amazing fecundity is due to the fact that the adult ovary, contains premeiotic oocyte progenitor cells, called oogonia, which produce a continuous supply of new oocytes throughout adult life. Oocyte progenitor cells can be easily identified based on their expression of Vasa, and their characteristic nuclear morphology. Thus, the zebrafish ovary provides a unique and powerful system to study the genetic regulation of oocyte production in a vertebrate animal. A method is presented here for identifying oocyte progenitor cells in the zebrafish ovary using whole-mount confocal immunofluorescence that is simple and accurate.

  17. Method for somatic cell nuclear transfer in zebrafish.

    PubMed

    Siripattarapravat, Kannika; Cibelli, Jose B

    2011-01-01

    Somatic cell nuclear transfer (SCNT) has been a well-known technique for decades and widely applied to generate identical animals, including ones with genetic alterations. The system has been demonstrated successfully in zebrafish. The elaborated requirements of SCNT, however, limit reproducibility of the established model to a few groups in zebrafish research community. In this chapter, we meticulously outline each step of the published protocol as well as preparations of equipments and reagents used in zebrafish SCNT. All describable detailed-tips are elaborated in texts and figures. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Light-Addressable Measurement of in Vivo Tissue Oxygenation in an Unanesthetized Zebrafish Embryo via Phase-Based Phosphorescence Lifetime Detection

    PubMed Central

    Huang, Shih-Hao; Yu, Chu-Hung; Chien, Yi-Lung

    2015-01-01

    We have developed a digital light modulation system that utilizes a modified commercial projector equipped with a laser diode as a light source for quantitative measurements of in vivo tissue oxygenation in an unanesthetized zebrafish embryo via phase-based phosphorescence lifetime detection. The oxygen-sensitive phosphorescent probe (Oxyphor G4) was first inoculated into the bloodstream of 48 h post-fertilization (48 hpf) zebrafish embryos via the circulation valley to rapidly disperse probes throughout the embryo. The unanesthetized zebrafish embryo was introduced into the microfluidic device and immobilized on its lateral side by using a pneumatically actuated membrane. By controlling the illumination pattern on the digital micromirror device in the projector, the modulated excitation light can be spatially projected to illuminate arbitrarily-shaped regions of tissue of interest for in vivo oxygen measurements. We have successfully measured in vivo oxygen changes in the cardiac region and cardinal vein of a 48 hpf zebrafish embryo that experience hypoxia and subsequent normoxic conditions. Our proposed platform provides the potential for the real-time investigation of oxygen distribution in tissue microvasculature that relates to physiological stimulation and diseases in a developing organism. PMID:25856326

  19. Observations using Phosphorus-31 nuclear magnetic resonance (31P-NMR) of structural changes in freeze-thawed hen egg yolk.

    PubMed

    Wakamatsu, Hiroki; Handa, Akihiro; Chiba, Kazuhiro

    2018-04-01

    Hen egg yolk (EY) has a complicated structure consisting of lipids and proteins, and its structure is deeply related with its functional properties. 31 P-NMR is an efficient technique to non-destructively detect the dynamic behaviour of phospholipids, the main component of bio-membranes. We determined conditions for measuring the 31 P NMR spectra of EY and identified the components. 31 P-NMR was used to detect phosvitin, inorganic phosphate, and lipoprotein as well as structural changes such as granule collapse and freeze-thaw denaturation as signal changes. Freeze-thaw denaturation generated a new denaturation peak. We separated aggregates of LDL from freeze-thawed plasma using centrifugation. TEM and 31 P-NMR observations revealed that the denaturation peak corresponded to LDL aggregates. The 31 P-NMR spectra suggested the formation of multiple forms of LDL aggregates in which the head groups of phospholipid molecules adopt a face-to-face orientation, similar to that observed following the flocculation of lipoproteins or in the lamellar-like structures of phospholipids. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Fertility results using bovine semen cryopreserved with extenders based on egg yolk and soy bean extract.

    PubMed

    van Wagtendonk-de Leeuw, A M; Haring, R M; Kaal-Lansbergen, L M; den Daas, J H

    2000-07-01

    Semen extenders containing components such as egg yolk and skim milk are difficult to standardize and they introduce the risk of microbial contamination. A well-defined extender not originating from animal tissues would present a valuable contribution to the AI industry. We evaluated the fertility of bovine semen cryopreserved with 3 different extenders: 1) TRIS-Standard, prepared at 2 local AI laboratories, containing 20% (v/v) pasteurized egg yolk, 2) TRIS-Concentrate, prepared by adding 20% (v/v) pasteurized egg yolk and 1:5 (v/v) nonpyrogenic water, and 3) Biociphos Plus, a soybean extract containing extender, prepared by adding 1:5 nonpyrogenic water. Ejaculates of 4 Holstein bulls were split into 3 aliquots and cryopreserved with the 3 extenders. Prior to this study, the semen dose-response curve for each of the 4 bulls was developed in a field trial by freezing the semen and randomly distributing the straws throughout the Netherlands for insemination. Optimal semen doses were thus established to detect the effect of extenders on fertility, evaluated by 56-day non-return rate (NR56), and by the estimated conception rate and the calving rate, given a conception. We used the multiphasic model developed by Grossman et al. (7). A total of 22,246 first and second inseminations were recorded. The NR56 ranged among bulls from 67.0 to 70.1% for Tris-Standard, from 67.5 to 69.9% for Tris-Concentrate and from 60.2 to 66.7% for Biociphos Plus. No significant differences in NR56 were detected between Tris-Standard and Tris-Concentrate (P=0.54), whereas Biociphos Plus resulted in a significantly lower NR56 than Tris-Standard and Tris-Concentrate (P<0.05). Estimated conception rate was 72.1, 73.6 and 69.6% and estimated calving rate, given a conception was 80.6, 78.3 and 77.1 for Tris-Standard, Tris-Concentrate and Biociphos Plus, respectively. These results indicate that 1) semen extended with a custom made TRIS-Concentrate can be succesfully used in the field resulting

  1. Multiplication of Salmonella Enteritidis in egg yolks after inoculation outside, on, and inside vitelline membranes and storage at different temperatures

    Prompt refrigeration to restrict bacterial growth is a widely acknowledged practice for reducing the risk of egg-borne transmission of Salmonella Enteritidis to consumers. A recently published federal regulation for S. Enteritidis control requires eggs to be refrigerated within 36 after they are la...

  2. Effects of in-feed egg yolk antibodies on Salmonella shedding, bacterial antibiotic resistance, and health of pigs.

    PubMed

    Mathew, Alan G; Rattanatabtimtong, Sukanya; Nyachoti, Charles M; Fang, Lin

    2009-02-01

    To determine effects of anti-Salmonella egg yolk antibodies on shedding and antibiotic resistance of Salmonella enterica Typhimurium, newly weaned pigs were randomly assigned to six dietary treatments. These treatment groups were (i) a control (basal) diet without additives and similar diets with (ii) egg yolk powder derived from chickens challenged with Salmonella Typhimurium antigens, (iii) a commercial egg yolk powder control, (iv) apramycin for 14 days followed by carbadox, (v) oxytetracycline, or (vi) spray-dried plasma protein. Treatments were provided beginning on day 3 of the trial, and all pigs were challenged with 5 ml of 10(8) CFU/ml Salmonella Typhimurium on day 7. Fecal samples were collected on days 0, 7, 8, 12, 14, 21, 58, 88, and 118 for isolation of Salmonella and Escherichia coli to determine shedding and antibiotic resistance patterns. Body weights, white blood cell counts, and plasma concentrations of anti-Salmonella immunoglobulin G and porcine interleukin 1beta were analyzed as indicators of animal health. The percentage of pigs shedding Salmonella was lower for antibiotic treatment groups compared with other groups; however, resistance was greater in E. coli from pigs fed antibiotics than in pigs in other treatment groups. Health and performance indicators (pig weight gains, white blood cell counts, and plasma concentrations of anti-Salmonella antibodies) did not differ between treatment groups. These studies indicate that feeding egg yolk containing anti-Salmonella immunoglobulin Y may not be effective in controlling shedding of Salmonella in pigs.

  3. Super-hydrophobic yolk-shell nanostructure with enhanced catalytic performance in the reduction of hydrophobic nitroaromatic compounds.

    PubMed

    Shi, Song; Wang, Min; Chen, Chen; Gao, Jin; Ma, Hong; Ma, Jiping; Xu, Jie

    2013-10-25

    A self-templating method to fabricate a super-hydrophobic yolk-shell nano-reactor was reported. Metal nanoparticles were encapsulated in the porous super-hydrophobic shell. This super-hydrophobic catalyst showed excellent performance in the reduction of nitroaromatic compounds in aqueous phase and a positive correlation was found between the reaction rate and the hydrophobicity of the substrate.

  4. Supplementation of laying-hen feed with palm tocos and algae astaxanthin for egg yolk nutrient enrichment.

    PubMed

    Walker, Laurie A; Wang, Tong; Xin, Hongwei; Dolde, David

    2012-02-29

    Adding supplements to hen feed can increase egg nutritional value. Astaxanthin, tocotrienols, and tocopherols are potent antioxidants that provide health benefits to humans. We hypothesized that the addition of these nutrients to hen feed would result in an increased nutrient content in egg yolk with minimum changes in functional properties. Laying hens (Hy-Line W-36 breed) were fed four diets with different supplementation levels of palm toco concentrate and algae biomass containing astaxanthin for 8 weeks. Egg yolks were analyzed for physical, chemical, and functional properties. The feed with the highest nutrient concentration was also studied for stability of these antioxidants using the Arrhenius approach. No significant differences were observed in functional properties except for emulsification capacity and sensory characteristics among eggs from different diet treatments. Changes in egg yolk color reached the maximum values at day 8. Incorporation of tocopherols and tocotrienols increased until day 8, astaxanthin incorporation increased until day 10, and all decreased thereafter. Feed nutrients resulted in a dose-response relationship of these compounds in the egg yolk. The transfer efficiency ranged from 0 to 9.9% for tocotrienols and tocopherols and from 7.6 to 14.9% for astaxanthin at their peak values. Results of the Arrhenius accelerated stability study showed significant differences in the shelf life of various nutrients, and these results can be used to properly formulate and store the feed materials.

  5. [Separation and identification of red pigments in natural red yolk of duck's eggs by HPLC-MS-MS].

    PubMed

    Liu, Liangzhong; Zhang, Min; Peng, Guanghua; Wang, Haibin; Zhang, Shenghua

    2004-05-01

    The natural red yolk of duck's eggs is produced by the laying duck in the lake areas in southward of China. In the laying duck breeding areas such as Honghu, Jianli, Xiantao, Tianmen and Hanchuan citys in Hubei Province, the culturists are used to feeding fresh pondweeds to the laying ducks. The yolk of duck's eggs is natural red with the chrominance reaching up to and/or above RCF (Roche Yolk Color Fan) 15. The red pigment components of natural red yolk of duck's eggs were separated and identified by thin layer chromatography (TLC), high performance liquid chromatography-mass spectrometry-mass spectrometry (HPLC-MS-MS) and high resolution electron impact-mass spectrometry (EI-MS). Four isomers of red pigments were separated by HPLC on a RP-C18 column with methanol-water (99.5:0.5, v/v) as mobile phase. The lambda(max) of the four components were 482, 488, 496, 501 nm, respectively, and all of them were single peak on chromatogram. They had the same molecular mass (Mr = 562), and had the same fragment peaks of MS2 with rhodoxanthin. The molecular formula of red pigments was determined as C40H50O2 by high resolution EI-MS. The results indicate that the red pigment is rhodoxanthin, and they are all cis-isomers of rhodoxanthin.

  6. Passive immunization with hyperimmune egg yolk IgY as prophylaxis and therapy for poultry diseases---A review

    Passive immunization with pathogen-specific egg yolk antibodies (IgY) is emerging as a potential alternative to antibiotics for the treatment and prevention of various human and animal diseases. Laying hens are an excellent source of high-quality polyclonal antibodies, which can be collected noninv...

  7. Effects of dietary supplementation with Gynura procumbens (Merr.) on egg yolk cholesterol, excreta microflora and laying hen performance.

    PubMed

    Lokhande, A; Ingale, S L; Lee, S H; Sen, S; Khong, C; Chae, B J; Kwon, I K

    2014-01-01

    Abstract 1. The present study investigated the effects of dietary supplementation with Gynura procumbens on egg yolk and serum cholesterol and triglycerides, excreta microflora, laying performance and egg quality. 2. A total of 160 Hy-Line Brown layers (45 weeks old) were randomly assigned into 4 treatments on the basis of laying performance. Each treatment had 4 replicates with 10 birds each. 3. Dietary treatments were basal diet supplemented with 0 (control), 2.5, 5.0 and 7.5 g/kg diet G. procumbens during 56-d feeding period. 4. Serum (d 21, 42 and 56) and egg yolk (d 28, 42 and 56) cholesterol and triglycerides concentrations were linearly reduced with increasing dietary concentrations of G. procumbens. 5. Increasing dietary concentrations of G. procumbens linearly reduced the excreta total anaerobic bacteria (d 28), Clostridium sp. and Escherichia coli (d 28 and 56) populations. 6. Overall egg production and egg mass were linearly increased, and overall feed efficiency was linearly improved with increase in dietary G. procumbens. 7. Dietary increasing concentrations of G. procumbens linearly improved egg yolk colour (d 28 and 56) and breaking strength of eggs (d 56). 8. The results obtained in the present experiment indicate that dietary supplementation with G. procumbens could reduce the egg yolk cholesterol, suppresses harmful excreta microflora and improves layers performance.

  8. Yolk-sac larval development of the substrate-brooding cichlid Archocentrus nigrofasciatus in relation to temperature.

    PubMed

    Vlahos, Nikolaos; Vasilopoulos, Michael; Mente, Eleni; Hotos, George; Katselis, George; Vidalis, Kosmas

    2015-09-01

    In order to conserve and culture the cichlid fish Archocentrus nigrofasciatus, more information about its reproductive biology and its larval behavior and morphogenesis is necessary. Currently, temperatures ranging from 21 to 27 °C are used in ornamental aquaculture hatcheries. Lower temperatures are preferred to reduce the costs of water heating, and 23 °C is usually the selected temperature. However, there is limited information on culturing protocols for ornamental species and most of the information generated on this topic remains scarce. Thus, the present study examines the morphological development of Archocentrus nigrofasciatus during the yolk-sac period up to the age of 100 h post-hatching in relation to 2 temperature regimes used in ornamental aquaculture: a temperature of 27 °C (thermal optimum) and a decreased temperature of 23 °C (thermal tolerance). The results of this study suggest that the 27 °C temperature generates intense morphological changes in yolk-sac development in a shorter period. This has advantages as it reduces the time of yolk-sac larval development, and, thus, minimizes the transition phase to exogenous feeding and maximizes the efficiency at which yolk is converted into body tissues. The present paper provides necessary information to produce freshwater ornamental fish with better practices so as to increase larval survival and capitalize on time for growth. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  9. Study on development of Vipera lebetina snake anti-venom in chicken egg yolk for passive immunization

    PubMed Central

    Zolfagharian, Hossein; Dounighi, Naser Mohammadpour

    2015-01-01

    Chicken egg yolk antibodies against Vipera lebetina venom were evaluated for their antivenom potential. White leghorn hens were immunized with detoxified V. lebetina venom (γ-irradiated venom). The detoxified venom (200 μg) was mixed with an equal volume of complete Freund's adjuvant and was injected intramuscularly into the hens. The antibodies showed high activity (1.6 LD50/mL) in egg yolks after 12 d of venom injection. The eggs were collected after 12 days, and the egg yolks were removed and washed with purified water to remove any contamination with egg whites. The purification was performed using a method described by Maya Devi et al., followed by gel filtration (Sephadex G-50). The purity and molecular weight of antivenom antibodies (IgY) were determined using electrophoresis, and the molecular weight was found to be approximately 185 kDa. The potency of IgY was 6 LD50/mL (mice), i.e., 1 mL of IgY could neutralize 43.8 μg of standard V. lebetina venom). Our results showed that chicken egg yolk antibodies were effective in neutralizing the lethality and several pharmacological effects of V. lebetina venom and could be used for developing effective antivenom. PMID:25700656

  10. Effects of dietary fats on egg quality and lipid parameters in serum and yolks of Shan Partridge Duck.

    PubMed

    Du, Xue; Liu, Yali; Lu, Lizhi; Wang, Weiqun; Zeng, Tao; Tian, Yong; Xu, Xiaoqin; Shen, Jianliang; Niu, Dong; Lu, Yingru

    2017-05-01

    The effects of different dietary fats with variable levels of polyunsaturated fatty acids (PUFAs) on egg quality of Shan Partridge Duck, serum, and yolk lipid parameters were examined in this study. A flock of 585 optimal produced ducks were selected and diets enriched with 0.5%, 1%, or 2% fish oil (F)/flaxseed oil (FL)/rapeseed oil (R)/tallow (T) plus basal diet were supplied through a 28-d period. Supplemental fat source and fat level had no effects on egg qualities. Proportions of yolk total cholesterol (TC), saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) were reduced (P < 0.001), while polyunsaturated fatty acids (PUFAs), ω-6 polyunsaturated fatty acids (n-6 PUFAs), ω-3 polyunsaturated fatty acids (n-3 PUFAs), Docosahexaenoic Acid (DHA), and Eicosapentaenoic Acid (EPA) were increased by fish oil, flaxseed oil, or rapeseed oil. Effects of supplementation increasing DHA and EPA were detected in F, FL, and R. Compared with C, fish oil significantly increased low-density lipoprotein cholesterol (LDL-C) in serum, flaxseed oil significantly reduced TC and increased very low-density lipoprotein cholesterol (VLDL-C), rapeseed oil significantly reduced TC and LDL-C in serum and increased VLDL-C, tallow significantly increased LDL-C. It is concluded that unsaturated fatty acids rich diets (fish oil, flaxseed oil, and rapeseed oil) might increase yolk PUFAs, reduce yolk cholesterol, and change serum lipid parameters without evident effect on egg qualities. © 2016 Poultry Science Association Inc.

  11. Evolutionary implications of interspecific variation in a maternal effect: a meta-analysis of yolk testosterone response to competition

    PubMed Central

    Navara, Kristen J.

    2016-01-01

    Competition between conspecifics during the breeding season can result in behavioural and physiological programming of offspring via maternal effects. For birds, in which maternal effects are best studied, it has been claimed that exposure to increased competition causes greater deposition of testosterone into egg yolks, which creates faster growing, more aggressive offspring; such traits are thought to be beneficial for high-competition environments. Nevertheless, not all species show a positive relationship between competitive interactions and yolk testosterone, and an explanation for this interspecific variation is lacking. We here test if the magnitude and direction of maternal testosterone allocated to eggs in response to competition can be explained by life-history traits while accounting for phylogenetic relationships. We performed a meta-analysis relating effect size of yolk testosterone response to competition with species coloniality, nest type, parental effort and mating type. We found that effect size was moderated by coloniality and nest type; colonial species and those with open nests allocate less testosterone to eggs when in more competitive environments. Applying a life-history perspective helps contextualize studies showing little or negative responses of yolk testosterone to competition and improves our understanding of how variation in this maternal effect may have evolved. PMID:28018636

  12. Comparison of hatching egg characteristics, embryo development, yolk absorption, hatch window, and hatchability of Pekin Duck eggs of different weights.

    PubMed

    Ipek, A; Sozcu, A

    2017-10-01

    This study was carried out to determine the hatching egg characteristics, embryo development and yolk absorption during incubation, hatch window, and hatchability of Pekin duck eggs of different weights. A total of 960 hatching eggs was obtained from a breeder flock 35 to 36 wk of age. The eggs were classed into 3 weight categories: "light" (L; <75 g), "medium" (M; 76 to 82 g), and "heavy" (H; >83 g). The albumen weight was the highest in the heavy eggs, whereas the yolk weight was higher in the medium and heavy eggs. Egg breaking strength was the highest with a value of 2.5 kg/cm2 in light eggs, whereas the thinnest eggshell (0.3862 mm) was observed in heavy eggs. pH of albumen and yolk was similar and ranged from 8.8 to 8.9 and 5.9 to 6.0, respectively.