WorldWideScience

Sample records for embryonic limb development

  1. Mechanobiology of embryonic limb development.

    Science.gov (United States)

    Nowlan, Niamh C; Murphy, Paula; Prendergast, Patrick J

    2007-04-01

    Considerable evidence exists to support the hypothesis that mechanical forces have an essential role in healthy embryonic skeletal development. Clinical observations and experimental data indicate the importance of muscle contractions for limb development. However, the influence of these forces is seldom referred to in biological descriptions of bone development, and perhaps this is due to the fact that the hypothesis that mechanical forces are essential for normal embryonic skeletal development is difficult to test and elaborate experimentally in vivo, particularly in humans. Computational modeling has the potential to address this issue by simulating embryonic growth under a range of loading conditions but the potential of such models has yet to be fully exploited. In this article, we review the literature on mechanobiology of limb development in three main sections: (a) experimental alteration of the mechanical environment, (b) mechanical properties of embryonic tissues, and (c) the use of computational models. Then we analyze the main issues, and suggest how experimental and computational fields could work closer together to enhance our understanding of mechanobiology of the embryonic skeleton.

  2. Manic fringe is not required for embryonic development, and fringe family members do not exhibit redundant functions in the axial skeleton, limb, or hindbrain

    Science.gov (United States)

    Moran, Jennifer L.; Shifley, Emily T.; Levorse, John M.; Mani, Shyamala; Ostmann, Kristin; Perez-Balaguer, Ariadna; Walker, Dawn M.; Vogt, Thomas F.; Cole, Susan E.

    2009-01-01

    Tight regulation of Notch pathway signaling is important in many aspects of embryonic development. Notch signaling can be modulated by expression of fringe genes, encoding glycosyltransferases that modify EGF repeats in the Notch receptor. Although Lunatic fringe (Lfng) has been shown to play important roles in vertebrate segmentation, comparatively little is known regarding the developmental functions of the other vertebrate fringe genes, Radical fringe (Rfng) and Manic fringe (Mfng). Here we report that Mfng expression is not required for embryonic development. Further, we find that despite significant overlap in expression patterns, we detect no obvious synergistic defects in mice in the absence of two, or all three, fringe genes during development of the axial skeleton, limbs, hindbrain and cranial nerves. PMID:19479951

  3. The Mouse Limb Anatomy Atlas: An interactive 3D tool for studying embryonic limb patterning

    Directory of Open Access Journals (Sweden)

    DeLaurier April

    2008-09-01

    Full Text Available Abstract Background The developing mouse limb is widely used as a model system for studying tissue patterning. Despite this, few references are available that can be used for the correct identification of developing limb structures, such as muscles and tendons. Existing textual references consist of two-dimensional (2D illustrations of the adult rat or mouse limb that can be difficult to apply when attempting to describe the complex three-dimensional (3D relationship between tissues. Results To improve the resources available in the mouse model, we have generated a free, web-based, interactive reference of limb muscle, tendon, and skeletal structures at embryonic day (E 14.5 http://www.nimr.mrc.ac.uk/3dlimb/. The Atlas was generated using mouse forelimb and hindlimb specimens stained using immunohistochemistry to detect muscle and tendon. Limbs were scanned using Optical Projection Tomography (OPT, reconstructed to make 3D models and annotated using computer-assisted segmentation tools in Amira 3D Visualisation software. The annotated dataset is visualised using Java, JAtlasView software. Users click on the names of structures and view their shape, position and relationship with other structures within the 3D model and also in 2D virtual sections. Conclusion The Mouse Limb Anatomy Atlas provides a novel and valuable tool for researchers studying limb development and can be applied to a range of research areas, including the identification of abnormal limb patterning in transgenic lines and studies of models of congenital limb abnormalities. By using the Atlas for "virtual" dissection, this resource offers an alternative to animal dissection. The techniques we have developed and employed are also applicable to many other model systems and anatomical structures.

  4. File list: DNS.Emb.10.AllAg.Embryonic_limb [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Emb.10.AllAg.Embryonic_limb mm9 DNase-seq Embryo Embryonic limb SRX191032,SRX19...1037 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Emb.10.AllAg.Embryonic_limb.bed ...

  5. File list: InP.Emb.50.AllAg.Embryonic_limb [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Emb.50.AllAg.Embryonic_limb mm9 Input control Embryo Embryonic limb SRX804047,S...69,SRX083262,SRX083272 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Emb.50.AllAg.Embryonic_limb.bed ...

  6. Gravity and embryonic development

    Science.gov (United States)

    Young, R. S.

    1976-01-01

    The relationship between the developing embryo (both plant and animal) and a gravitational field has long been contemplated. The difficulty in designing critical experiments on the surface of the earth because of its background of 1 g, has been an obstacle to a resolution of the problem. Biological responses to gravity (particularly in plants) are obvious in many cases; however, the influence of gravity as an environmental input to the developing embryo is not as obvious and has proven to be extremely difficult to define. In spite of this, over the years numerous attempts have been made using a variety of embryonic materials to come to grips with the role of gravity in development. Three research tools are available: the centrifuge, the clinostat, and the orbiting spacecraft. Experimental results are now available from all three sources. Some tenuous conclusions are drawn, and an attempt at a unifying theory of gravitational influence on embryonic development is made.

  7. Cell to cell signalling during vertebrate limb bud development

    NARCIS (Netherlands)

    Panman, Lia

    2004-01-01

    Communication between cells is essential during embryonic development. The vertebrate limb bud provides us a model to study signalling interactions between cells during patterning of embryonic tissues and organogenesis. In chapter 1 I give an introduction about limb bud development that is focussed

  8. The Evolution of Lineage-Specific Regulatory Activities in the Human Embryonic Limb

    OpenAIRE

    Cotney, Justin; Leng, Jing; Yin, Jun; Reilly, Steven K.; DeMare, Laura E.; Emera, Deena; Ayoub, Albert E.; Rakic, Pasko; Noonan, James P.

    2013-01-01

    The evolution of human anatomical features likely involved changes in gene regulation during development. However, the nature and extent of human-specific developmental regulatory functions remain unknown. We obtained a genome-wide view of cis-regulatory evolution in human embryonic tissues by comparing the histone modification H3K27ac, which provides a quantitative readout of promoter and enhancer activity, during human, rhesus, and mouse limb development. Based on increased H3K27ac, we find...

  9. Embryonic development during chronic acceleration

    Science.gov (United States)

    Smith, A. H.; Abbott, U. K.

    1982-01-01

    Experiments carried out on chicken eggs indicate that the embryo is affected during very early development, especially over the first four days, and during hatching. In the first four days, the brain develops as well as the anlage for all other organs. In addition, the heart commences to function and the extraembryonic membranes that compartmentalize the egg contents form. The latter require an appreciable extension and folding of tissue which may be disrupted by the mechanical load. Observations of embryonic abnormalities that occur during chronic acceleration suggest an inhibition of development of the axial skeleton, which is rarely seen otherwise, a general retardation of embryonic growth, and circulatory problems. The final stages of development (after 18 days) involve the uptake of fluids, the transition to aerial respiration, and the reorientation of the embryo into a normal hatching position. At 4 G mortality is very high during this period, with a majority of embryos failing to reorient into the normal hatching position.

  10. Differentiation of cartilaginous anlage in entire embryonic mouse limbs cultured in a rotating bioreactor.

    Science.gov (United States)

    Duke, P.; Oakley, C.; Montufar-Solis, D.

    The embryonic mammalian limb is sensitive both in vivo and in vitro to changes in gravitational force. Hypergravity of centrifugation and microgravity of space decreased size of elements due to precocious or delayed chondrogenesis respectively. In recapitulating spaceflight experiments, premetatarsals were cultured in suspension in a low stress, low sheer rotating bioreactor, and found to be shorter than those cultured in standard culture dishes, and cartilage development was delayed. This study only measured length of the metatarsals, and did not account for possible changes in width and/or in form of the skeletal elements. Shorter cartilage elements in limbbuds cultured in the bioreactor may be due to the ability of the system to reproduce a more in vivo 3D shape than traditional organ cultures. Tissues subjected to traditional organ cultures become flattened by their own weight, attachment to the filter, and restrictions imposed by nutrient diffusion. The purpose of the current experiment was to determine if entire limb buds could be successfully cultured in the bioreactor, and to compare the effects on 3D shape with that of culturing in a culture dish system. Fore and hind limbs from E11-E13 ICR mouse embryos were placed either in the bioreactor, in Trowell culture, or fixed as controls. Limbbuds were cultured for six days, fixed, and processed either as whole mounts or embedded for histology. Qualitative analysis revealed that the Trowell culture specimens were flattened, while bioreactor culture specimens had a more in vivo-like 3D limb shape. Sections of limbbuds from both types of cultures had excellent cartilage differentiation, with apparently more cell maturation, and hypertrophy in the specimens cultured in the bioreactor. Morphometric quantitation of the cartilaginous elements for comparisons of the two culture systems was complicated due to some limb buds fusing together during culture. This problem was especially noticeable in the younger limbs, and

  11. Mechanisms of embryonic stomach development.

    Science.gov (United States)

    McCracken, Kyle W; Wells, James M

    2017-06-01

    The stomach is a digestive organ that has important roles in human physiology and pathophysiology. The developmental origin of the stomach is the embryonic foregut, which also gives rise a number of other structures. There are several signaling pathways and transcription factors that are known to regulate stomach development at different stages, including foregut patterning, stomach specification, and gastric regionalization. These developmental events have important implications in later homeostasis and disease in the adult stomach. Here we will review the literature that has shaped our current understanding of the molecular mechanisms that coordinate gastric organogenesis. Further we will discuss how developmental paradigms have guided recent efforts to differentiate stomach tissue from pluripotent stem cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Learning about Vertebrate Limb Development

    Science.gov (United States)

    Liang, Jennifer O.; Noll, Matthew; Olsen, Shayna

    2014-01-01

    We have developed an upper-level undergraduate laboratory exercise that enables students to replicate a key experiment in developmental biology. In this exercise, students have the opportunity to observe live chick embryos and stain the apical ectodermal ridge, a key tissue required for development of the vertebrate limb. Impressively, every…

  13. Chondrogenesis in aggregates of embryonic limb cells grown in a rotating wall vessel

    Science.gov (United States)

    Duke, J.; Daane, E.; Arizpe, J.; Montufar-Solis, D.

    Previous studies in this lab have shown that chondrogenesis is affected in growth plates of rats exposed to microgravity, and in micromass cultures of embryonic limb mesenchyme differentiating in space. In order to provide a three dimensional aspect not seen in the micromass system, and a tissue homogeneity not possible with explants of limb or limb elements, and to alleviate certain difficulties regarding crew time and stowage, we began culturing embryonic limb cells in Rotating Wall Vessels (RWV). First, these cells were attached to beads, and grown for up to 65 days in a type of RWV known as STLV at the Johnson Space Center. During this time, the cells and beads aggregated and the aggregates continued to increase in size, and differentiated into Alcian blue staining chondrocytes. Because our intent was to use these aggregates for implanting into bony defects in addition to their use in studies of chondrogenic regulation at 1g and mug, aggregates of these cells without beads were grown in the commercially available version of the STLV, and their ability to ossify when subcutaneously implanted assessed.

  14. Embryonic Development In Clarias gariepinus (Buchell, 1822 ...

    African Journals Online (AJOL)

    The embryonic development in Clarias gariepinus was studied under laboratory conditions. The development stages of eggs starting from first cleavage to hatching were examined microscopically. The accurate timing and detailed description of each stage were recorded. Photomicrograph of important stages, segmentation ...

  15. Limb development: a paradigm of gene regulation.

    Science.gov (United States)

    Petit, Florence; Sears, Karen E; Ahituv, Nadav

    2017-04-01

    The limb is a commonly used model system for developmental biology. Given the need for precise control of complex signalling pathways to achieve proper patterning, the limb is also becoming a model system for gene regulation studies. Recent developments in genomic technologies have enabled the genome-wide identification of regulatory elements that control limb development, yielding insights into the determination of limb morphology and forelimb versus hindlimb identity. The modulation of regulatory interactions - for example, through the modification of regulatory sequences or chromatin architecture - can lead to morphological evolution, acquired regeneration capacity or limb malformations in diverse species, including humans.

  16. Development and the evolvability of human limbs.

    Science.gov (United States)

    Young, Nathan M; Wagner, Günter P; Hallgrímsson, Benedikt

    2010-02-23

    The long legs and short arms of humans are distinctive for a primate, the result of selection acting in opposite directions on each limb at different points in our evolutionary history. This mosaic pattern challenges our understanding of the relationship of development and evolvability because limbs are serially homologous and genetic correlations should act as a significant constraint on their independent evolution. Here we test a developmental model of limb covariation in anthropoid primates and demonstrate that both humans and apes exhibit significantly reduced integration between limbs when compared to quadrupedal monkeys. This result indicates that fossil hominins likely escaped constraints on independent limb variation via reductions to genetic pleiotropy in an ape-like last common ancestor (LCA). This critical change in integration among hominoids, which is reflected in macroevolutionary differences in the disparity between limb lengths, facilitated selection for modern human limb proportions and demonstrates how development helps shape evolutionary change.

  17. Embryonic development of Pelteobagrus fulvidraco (Richardson, 1846)

    Science.gov (United States)

    Wang, Weimin; Abbas, Khalid; Yan, Ansheng

    2006-12-01

    For production enhancement and procedure upgrade, the developmental phases of laboratory-reared eggs of catfish Pelteobagrus fulvidraco were investigated. Twenty mature females and 10 males were collected from Dadongmen wholesale fisheries market in Wuhan City on May 8, 2003. Zygotes were stripped from mature fish after hormone-induced ovulation, fertilized, and incubated through whole embryonic development. The fertilized eggs were stocked in density of 100 eggs/L in white square tanks of 10 L. Incubation water was dechlorinated tap water with continuous aeration. The tanks were lit directly with 60 W fluorescent bulbs with a 12 light: 12 dark photoperiod. Water temperature, dissolved oxygen and pH were 29.0±0.5°C, 6.7±0.4 mg/L and 7.4±2, respectively. The results showed that the eggs of P. fulvidraco were yellow, sticky and contained much yolk. The mean diameter of fertilized eggs was 2.03 mm. At the water temperature of 29.0±0.5°C, the ontogenesis spent about 33 h after fertilization. From fertilization to hatching, the embryonic development can be divided into 30 40 phases, which varies in the emphasis and direction of development. The detailed embryonic movement was also described.

  18. Development and the evolvability of human limbs

    OpenAIRE

    Young, Nathan M.; Wagner, Günter P.; Hallgrímsson, Benedikt

    2010-01-01

    The long legs and short arms of humans are distinctive for a primate, the result of selection acting in opposite directions on each limb at different points in our evolutionary history. This mosaic pattern challenges our understanding of the relationship of development and evolvability because limbs are serially homologous and genetic correlations should act as a significant constraint on their independent evolution. Here we test a developmental model of limb covariation in anthropoid primate...

  19. Different regulation of limb development by p63 transcript variants.

    Directory of Open Access Journals (Sweden)

    Manabu Kawata

    Full Text Available The apical ectodermal ridge (AER, located at the distal end of each limb bud, is a key signaling center which controls outgrowth and patterning of the proximal-distal axis of the limb through secretion of various molecules. Fibroblast growth factors (FGFs, particularly Fgf8 and Fgf4, are representative molecules produced by AER cells, and essential to maintain the AER and cell proliferation in the underlying mesenchyme, meanwhile Jag2-Notch pathway negatively regulates the AER and limb development. p63, a transcription factor of the p53 family, is expressed in the AER and indispensable for limb formation. However, the underlying mechanisms and specific roles of p63 variants are unknown. Here, we quantified the expression of p63 variants in mouse limbs from embryonic day (E 10.5 to E12.5, and found that ΔNp63γ was strongly expressed in limbs at all stages, while TAp63γ expression was rapidly increased in the later stages. Fluorescence-activated cell sorting analysis of limb bud cells from reporter mouse embryos at E11.5 revealed that all variants were abundantly expressed in AER cells, and their expression was very low in mesenchymal cells. We then generated AER-specific p63 knockout mice by mating mice with a null and a flox allele of p63, and Msx2-Cre mice (Msx2-Cre;p63Δ/fl. Msx2-Cre;p63Δ/fl neonates showed limb malformation that was more obvious in distal elements. Expression of various AER-related genes was decreased in Msx2-Cre;p63Δ/fl limb buds and embryoid bodies formed by p63-knockdown induced pluripotent stem cells. Promoter analyses and chromatin immunoprecipitation assays demonstrated Fgf8 and Fgf4 as transcriptional targets of ΔNp63γ, and Jag2 as that of TAp63γ. Furthermore, TAp63γ overexpression exacerbated the phenotype of Msx2-Cre;p63Δ/fl mice. These data indicate that ΔNp63 and TAp63 control limb development through transcriptional regulation of different target molecules with different roles in the AER. Our findings

  20. Retinoic acid signalling in the development of the epidermis, the limbs and the secondary palate

    NARCIS (Netherlands)

    Mammadova, A.; Zhou, H.; Carels, C.E.L.; Hoff, J.W. Von den

    2016-01-01

    Retinoic acid (RA), the active derivative of vitamin A, is one of the major regulators of embryonic development, including the development of the epidermis, the limbs and the secondary palate. In the embryo, RA levels are tightly regulated by the activity of RA synthesizing and degrading enzymes.

  1. Embryonic development of the cricket Gryllus bimaculatus.

    Science.gov (United States)

    Donoughe, Seth; Extavour, Cassandra G

    2016-03-01

    Extensive research into Drosophila melanogaster embryogenesis has improved our understanding of insect developmental mechanisms. However, Drosophila development is thought to be highly divergent from that of the ancestral insect and arthropod in many respects. We therefore need alternative models for arthopod development that are likely to be more representative of basally-branching clades. The cricket Gryllus bimaculatus is such a model, and currently has the most sophisticated functional genetic toolkit of any hemimetabolous insect. The existing cricket embryonic staging system is fragmentary, and it is based on morphological landmarks that are not easily visible on a live, undissected egg. To address this problem, here we present a complementary set of "egg stages" that serve as a guide for identifying the developmental progress of a cricket embryo from fertilization to hatching, based solely on the external appearance of the egg. These stages were characterized using a combination of brightfield timelapse microscopy, timed brightfield micrographs, confocal microscopy, and measurements of egg dimensions. These egg stages are particularly useful in experiments that involve egg injection (including RNA interference, targeted genome modification, and transgenesis), as injection can alter the speed of development, even in control treatments. We also use 3D reconstructions of fixed embryo preparations to provide a comprehensive description of the morphogenesis and anatomy of the cricket embryo during embryonic rudiment assembly, germ band formation, elongation, segmentation, and appendage formation. Finally, we aggregate and schematize a variety of published developmental gene expression patterns. This work will facilitate further studies on G. bimaculatus development, and serve as a useful point of reference for other studies of wild type and experimentally manipulated insect development in fields from evo-devo to disease vector and pest management. Copyright

  2. Mathematical modeling of vertebrate limb development.

    Science.gov (United States)

    Zhang, Yong-Tao; Alber, Mark S; Newman, Stuart A

    2013-05-01

    In this paper, we review the major mathematical and computational models of vertebrate limb development and their roles in accounting for different aspects of this process. The main aspects of limb development that have been modeled include outgrowth and shaping of the limb bud, establishment of molecular gradients within the bud, and formation of the skeleton. These processes occur interdependently during development, although (as described in this review), there are various interpretations of the biological relationships among them. A wide range of mathematical and computational methods have been used to study these processes, including ordinary and partial differential equation systems, cellular automata and discrete, stochastic models, finite difference methods, finite element methods, the immersed boundary method, and various combinations of the above. Multiscale mathematical modeling and associated computational simulation have become integrated into the study of limb morphogenesis and pattern formation to an extent with few parallels in the field of developmental biology. These methods have contributed to the design and analysis of experiments employing microsurgical and genetic manipulations, evaluation of hypotheses for limb bud outgrowth, interpretation of the effects of natural mutations, and the formulation of scenarios for the origination and evolution of the limb skeleton. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Hyaluronic acid in the tail and limb of amphibians and lizards recreates permissive embryonic conditions for regeneration due to its hygroscopic and immunosuppressive properties.

    Science.gov (United States)

    Alibardi, Lorenzo

    2017-12-01

    The present review focuses on the role of hyaluronate (hyaluronic acid; HA) during limb and tail regeneration in amphibians and lizards mainly in relation to cells of the immune system. This non-sulfated glycosaminoglycan (GAG) increases in early stages of wound healing and blastema formation, like during limb or tail embryogenesis, when the immune system is still immature. The formation of a regenerating blastema occurs by the accumulation of mesenchymal cells displaying embryonic-like antigens and HA. This GAG adsorbs large amount of water and generates a soft tissue over 80% hydrated where mesenchymal and epithelial cells can move and interact, an obligatory passage for organ regeneration. GAGs and HA in particular rise to a high amount and coat plasma membranes of blastema cells forming a shield that likely impedes to the circulating immune cells to elicit an immune reaction against the embryonic-like antigens present on blastema cells. The evolution of limb-tail regeneration in amphibians dates back to the Devonian-Carboniferous, while tail regeneration in lizards is a more recent evolution process, possibly occurred since the Jurassic, which is unique among amniotes. Both processes are associated with the reactivation of proliferating embryonic programs that involve the upregulation of genes for Wnt, non-coding RNAs, and HA synthesis in an immune-suppress organ, the regenerative blastema. Failure of maintaining a lasting HA synthesis for the formation of a highly hydrated blastema leads to scarring, the common healing process of amniotes equipped with an efficient immune system. The study of amphibian and lizard regeneration indicates that attempts to stimulate organ regeneration in other vertebrates require the induction of a highly hydrated and immune-depressed, HA-rich environment, similar to the extracellular environment present during development. © 2017 Wiley Periodicals, Inc.

  4. Avian embryonic development in hyperdynamic environments

    Science.gov (United States)

    Abbott, U. K.; Smith, A. H.

    1983-01-01

    Embryos which developed for 24 hours in the oviduct of hens maintained at 2 G and which were subsequently incubated at Earth gravity had a 14% reduction in hatchability. Increased mortality during the first 4 days, and an increase in embryonic abnormalities were of the types usually found during the first mortality peak (2-3 days). Embryos in eggs that were produced at Earth gravity and continued their development on the centrifuge at fields of 2 G or less did not appear to be greatly affected by the treatment. At 4 G, 91% of the embryos died, mostly on the first and second days of incubation. Abnormalities prominent in the centrifuged eggs include: (a) a failure of the primitive streak to develop; (b) interference with the development of the axial skeleton; (c) multiple hemorrhages, mostly petechial which is consistent with capillary fragility; and (d) retardation of embryo growth, possibly caused by an interference with gaseous diffusion, the result of an acceleration-induced increase in gas density in the centrifuging incubator.

  5. Evolution of embryonic development in nematodes

    Directory of Open Access Journals (Sweden)

    Schulze Jens

    2011-09-01

    Full Text Available Abstract Background Nematodes can be subdivided into basal Enoplea (clades 1 and 2 and more derived Chromadorea (clades 3 to 12. Embryogenesis of Caenorhabditis elegans (clade 9 has been analyzed in most detail. Their establishment of polarity and asymmetric cleavage requires the differential localization of PAR proteins. Earlier studies on selected other nematodes revealed that embryonic development of nematodes is more diverse than the essentially invariant development of C. elegans and the classic study object Ascaris had suggested. To obtain a more detailed picture of variations and evolutionary trends we compared embryonic cell lineages and pattern formation in embryos of all 12 nematode clades. Methods The study was conducted using 4-D microscopy and 3-D modeling of developing embryos. Results We found dramatic differences compared to C. elegans in Enoplea but also considerable variations among Chromadorea. We discovered 'Polarity Organizing Centers' (POCs that orient cleavage spindles along the anterior-posterior axis in distinct cells over consecutive cell generations. The resulting lineally arranged blastomeres represent a starting point for the establishment of bilateral symmetry within individual lineages. We can discern six different early cleavage types and suggest that these variations are due to modifications in the activity of the POCs in conjunction with changes in the distribution of PAR proteins. In addition, our studies indicate that lineage complexity advanced considerably during evolution, that is we observe trends towards an increase of somatic founder cells, from monoclonal to polyclonal lineages and from a variable (position-dependent to an invariable (lineage-dependent way of cell fate specification. In contrast to the early phase of embryogenesis, the second half ('morphogenesis' appears similar in all studied nematodes. Comparison of early cleavage between the basal nematode Tobrilus stefanskii and the tardigrade

  6. Chondrogenesis of embryonic limb bud cells in micromass culture progresses rapidly to hypertrophy and is modulated by hydrostatic pressure.

    Science.gov (United States)

    Saha, Anurati; Rolfe, Rebecca; Carroll, Simon; Kelly, Daniel J; Murphy, Paula

    2017-04-01

    Chondrogenesis in vivo is precisely controlled in time and space. The entire limb skeleton forms from cells at the core of the early limb bud that condense and undergo chondrogenic differentiation. Whether they form stable cartilage at the articular surface of the joint or transient cartilage that progresses to hypertrophy as endochondral bone, replacing the cartilage template of the skeletal rudiment, is spatially controlled over several days in the embryo. Here, we follow the differentiation of cells taken from the early limb bud (embryonic day 11.5), grown in high-density micromass culture and show that a self-organising pattern of evenly spaced cartilage nodules occurs spontaneously in growth medium. Although chondrogenesis is enhanced by addition of BMP6 to the medium, the spatial pattern of nodule formation is disrupted. We show rapid progression of the entire nodule to hypertrophy in culture and therefore loss of the local signals required to direct formation of stable cartilage. Dynamic hydrostatic pressure, which we have previously predicted to be a feature of the forming embryonic joint region, had a stabilising effect on chondrogenesis, reducing expression of hypertrophic marker genes. This demonstrates the use of micromass culture as a relatively simple assay to compare the effect of both biophysical and molecular signals on spatial and temporal control of chondrogenesis that could be used to examine the response of different types of progenitor cell, both adult- and embryo-derived.

  7. Programmed cell senescence during mammalian embryonic development.

    Science.gov (United States)

    Muñoz-Espín, Daniel; Cañamero, Marta; Maraver, Antonio; Gómez-López, Gonzalo; Contreras, Julio; Murillo-Cuesta, Silvia; Rodríguez-Baeza, Alfonso; Varela-Nieto, Isabel; Ruberte, Jesús; Collado, Manuel; Serrano, Manuel

    2013-11-21

    Cellular senescence disables proliferation in damaged cells, and it is relevant for cancer and aging. Here, we show that senescence occurs during mammalian embryonic development at multiple locations, including the mesonephros and the endolymphatic sac of the inner ear, which we have analyzed in detail. Mechanistically, senescence in both structures is strictly dependent on p21, but independent of DNA damage, p53, or other cell-cycle inhibitors, and it is regulated by the TGF-β/SMAD and PI3K/FOXO pathways. Developmentally programmed senescence is followed by macrophage infiltration, clearance of senescent cells, and tissue remodeling. Loss of senescence due to the absence of p21 is partially compensated by apoptosis but still results in detectable developmental abnormalities. Importantly, the mesonephros and endolymphatic sac of human embryos also show evidence of senescence. We conclude that the role of developmentally programmed senescence is to promote tissue remodeling and propose that this is the evolutionary origin of damage-induced senescence. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Development of rat embryonic spinal ganglion cells in damaged nerve.

    Science.gov (United States)

    Petrova, E S; Isaeva, E N; Korzhevskii, D E

    2014-09-01

    The development of dissociated cells from rat embryonic spinal ganglion after transplantation to damaged nerve of adult animals was studied using immunohistochemical differentiation markers of neural and glial cells. The cell suspension obtained after dissociation of rat embryonic spinal ganglia (embryonic day 15) was injected into the proximal segment of crushed sciatic nerve. The nerve was damaged by ligation for 40 sec. Progenitor cells were labeled with 5-bromo-2'-deoxyuridine (BrdU) before transplantation. BrdU-immunopositive cells were detected in the nerve trunks of recipients on days 1, 21, and 28 after transplantation. Dissociated cells of rat embryonic spinal ganglion (embryonic day 15) survived for at least 4 weeks after transplantation to the nerve and differentiate into NeuN-immunopositive neurons with morphological properties of sensory neurons and satellite cells containing S100 protein.

  9. Extracellular matrix, cell skeletons, and embryonic development.

    Science.gov (United States)

    Hay, E D

    1989-09-01

    During embryonic development, the extracellular matrix (ECM) promotes the production of differentiated products by epithelial cells and the migration of mesenchymal cells, and probably also plays a role in epithelial-mesenchymal transformation. Here we examine the role of the cell skeleton (actin, microtubules, intermediate filaments) in mediating matrix effects on mesenchymal cell morphology, migration, and formation. The interaction of both epithelial cells and mesenchymal cells with ECM seems to involve the actin cortex, which is best developed in the base of the epithelial cell, where it attaches to underlying matrix via membrane-intercalated receptors. To interact with the matrix, the fibroblast has appropriate ECM receptors and an actin cortex around the whole cell. The actin cortex is absolutely required for assumption of bipolar shape, elongation, and movement through the matrix. Since the cortex seems to be anchored to the matrix, it is unlikely that it moves during cell migration. A new hypothesis states that the microtubule- and intermediate filament-rich endoplasm, containing the nucleus, moves past the actin cortex-receptor-matrix complex into the newly synthesized front end of the mesenchymal cell to effect forward movement. When epithelial cells transform into mesenchyme in the embryo, or when they are induced to do this in vitro, they switch from the keratin intermediate filament profile to one rich in vimentin, and the effect of cell matrix interaction on cell shape is profoundly altered. Vimentin-actin interactions with ECM may be a major factor in the ability of a cell to become mesenchymal.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Function of JARID2 in bovines during early embryonic development

    Directory of Open Access Journals (Sweden)

    Yao Fu

    2017-12-01

    Full Text Available Histone lysine modifications are important epigenetic modifications in early embryonic development. JARID2, which is a member of the jumonji demethylase protein family, is a regulator of early embryonic development and can regulate mouse development and embryonic stem cell (ESC differentiation by modifying histone lysines. JARID2 can affect early embryonic development by regulating the methylation level of H3K27me3, which is closely related to normal early embryonic development. To investigate the expression pattern of JARID2 and the effect of JARID2-induced H3K27 methylation in bovine oocytes and early embryonic stages, JARID2 mRNA expression and localization were detected in bovine oocytes and early embryos via qRT-PCR and immunofluorescence in the present study. The results showed that JARID2 is highly expressed in the germinal vesicle (GV, MII, 2-cell, 4-cell, 8-cell, 16-cell and blastocyst stages, but the relative expression level of JARID2 in bovine GV oocytes is significantly lower than that at other oocyte/embryonic stages (p < 0.05, and JARID2 is expressed primarily in the nucleus. We next detected the mRNA expression levels of embryonic development-related genes (OCT4, SOX2 and c-myc after JARID2 knockdown through JARID2-2830-siRNA microinjection to investigate the molecularpathwayunderlying the regulation of H3K27me3 by JARID2 during early embryonic development. The results showed that the relative expression levels of these genes in 2-cell embryos weresignificantly higher than those in the blastocyst stage, and expression levels were significantly increased after JARID2 knockdown. In summary, the present study identified the expression pattern of JARID2 in bovine oocytes and at each early embryonic stage, and the results suggest that JARID2 plays a key role in early embryonic development by regulating the expression of OCT4, SOX2 and c-myc via modification of H3K27me3 expression. This work provides new data for improvements in the

  11. A trade-off between embryonic development rate and immune function of avian offspring is concealed by embryonic temperature

    Science.gov (United States)

    Martin, Thomas E.; Arriero, Elena; Majewska, Ania

    2011-01-01

    Long embryonic periods are assumed to reflect slower intrinsic development that are thought to trade off to allow enhanced physiological systems, such as immune function. Yet, the relatively rare studies of this trade-off in avian offspring have not found the expected trade-off. Theory and tests have not taken into account the strong extrinsic effects of temperature on embryonic periods of birds. Here, we show that length of the embryonic period did not explain variation in two measures of immune function when temperature was ignored, based on studies of 34 Passerine species in tropical Venezuela (23 species) and north temperate Arizona (11 species). Variation in immune function was explained when embryonic periods were corrected for average embryonic temperature, in order to better estimate intrinsic rates of development. Immune function of offspring trades off with intrinsic rates of embryonic development once the extrinsic effects of embryonic temperatures are taken into account.

  12. Embryonic development of Anodontites trapesialis (Lamarck, 1819) (Bivalvia: Mycetopodidae)

    OpenAIRE

    Silva-Souza,AT.; Guardia-Felipi,P.; Arrebola,NR.

    2011-01-01

    The phases of embryonic development of Anodontites trapesialis lasidia are described for the first time. Adult specimens were obtained from two fish farms located in Londrina, Paraná, Brazil. The internal demibranchs of 120 individuals were studied using a routine histological technique; 70 of these carried eggs and/or larvae in the marsupium and were utilized for the description of the phases of embryonic development. The demibranchs of five specimens were evaluated by scanning electron micr...

  13. Stepwise development of hematopoietic stem cells from embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Kenji Matsumoto

    Full Text Available The cellular ontogeny of hematopoietic stem cells (HSCs remains poorly understood because their isolation from and their identification in early developing small embryos are difficult. We attempted to dissect early developmental stages of HSCs using an in vitro mouse embryonic stem cell (ESC differentiation system combined with inducible HOXB4 expression. Here we report the identification of pre-HSCs and an embryonic type of HSCs (embryonic HSCs as intermediate cells between ESCs and HSCs. Both pre-HSCs and embryonic HSCs were isolated by their c-Kit(+CD41(+CD45(- phenotype. Pre-HSCs did not engraft in irradiated adult mice. After co-culture with OP9 stromal cells and conditional expression of HOXB4, pre-HSCs gave rise to embryonic HSCs capable of engraftment and long-term reconstitution in irradiated adult mice. Blast colony assays revealed that most hemangioblast activity was detected apart from the pre-HSC population, implying the early divergence of pre-HSCs from hemangioblasts. Gene expression profiling suggests that a particular set of transcripts closely associated with adult HSCs is involved in the transition of pre-HSC to embryonic HSCs. We propose an HSC developmental model in which pre-HSCs and embryonic HSCs sequentially give rise to adult types of HSCs in a stepwise manner.

  14. Wnt-3a is critical for caudal embryonic development

    Energy Technology Data Exchange (ETDEWEB)

    Camper, S.A.; Greco, T.L.; Newhouse, M.M. [Univ. of Michigan Medical School, Ann Arbor, MI (United States)] [and others

    1994-09-01

    Skeletal and neural tube defects represent an important class of birth defects. The majority of mouse mutants with neural tube defects also have malformations of the tail. Vestigial tail (vt) is an autosomal recessive mouse mutation characterized by reduction or absence of the tail, vertebral abnormalities, and reduced fertility. The phenotype has been described as the result of failure of cell migration through the primitive streak, causing abnormalities in the development of the neural tube and a reduction in the ventral ectodermal ridge. Wnt3a is an excellent candidate gene for vt because Wnt3a is expressed in the primitive streak and in the embryonic mesoderm, and it is thought to be involved in cell-to-cell communication and formation of the dorsal-ventral axis in the CNS. A lack of Wnt3a might be expected to result in overdorsalization of the neural tube and reduction of the ventral ectodermal ridge characteristic of vt/vt embryos. In a high resolution backcross segregating vt, we observed no recombination between vt and Wnt3a in 363 individuals analyzed. In vt/vt mice, Southern blot analysis revealed no abnormalities in the Wnt3a gene, and the Wnt3a cDNA sequence does not encode any amino acid changes. Whole mount in situ hybridization analysis demonstrated that Wnt3a expression is severely reduced in the developing tailbud of day 9.5 vt/vt embryos, suggestive of a lesion in the regulation on Wnt3a expression. An alleleism test, carried out by mating vt/vt males with Wnt3a +/Wnt3a- females, demonstrated that vt and Wnt3a are noncomplementing alleles. All of the compound heterozygotes exhibited severe tail defects, including occasional examples of hind limb parlaysis and spina bifida. The vertebral defects are intermediate between those of vt and Wnt3a homozygotes, suggesting that the concentration of Wnt3a correlates with the severity of the defect.

  15. Synthetic strategies for studying embryonic development.

    Science.gov (United States)

    Ouyang, Xiaohu; Chen, James K

    2010-06-25

    Developmental biology has evolved from a descriptive science to one based on genetic principles and molecular mechanisms. Although molecular biology and genetic technologies have been the primary drivers of this transformation, synthetic strategies have been increasingly utilized to interrogate the mechanisms of embryonic patterning with spatial and temporal precision. In this review, we survey how chemical tools and engineered proteins have been used to perturb developmental processes at the DNA, RNA, protein, and cellular levels. We discuss the design principles, experimental capabilities, and limitations of each method, as well as future challenges for the chemical and developmental biology communities.

  16. Contributions of Noncanonical Smoothened Signaling During Embryonic Development.

    Science.gov (United States)

    Pandit, Tanushree; Ogden, Stacey K

    2017-01-01

    The Sonic Hedgehog (Shh) signaling pathway is active during embryonic development in metazoans, and provides instructional cues necessary for proper tissue patterning. The pathway signal transducing component, Smoothened (Smo), is a G protein-coupled receptor (GPCR) that has been demonstrated to signal through at least two effector routes. The first is a G protein-independent canonical route that signals to Gli transcriptional effectors to establish transcriptional programs specifying cell fate during early embryonic development. The second, commonly referred to as the noncanonical Smo signal, induces rapid, transcription-independent responses that are essential for establishing and maintaining distinct cell behaviors during development. Herein, we discuss contributions of this noncanonical route during embryonic development. We also highlight important open questions regarding noncanonical Smo signal route selection during development, and consider implications of noncanonical signal corruption in disease.

  17. Contributions of Noncanonical Smoothened Signaling During Embryonic Development

    Directory of Open Access Journals (Sweden)

    Tanushree Pandit

    2017-10-01

    Full Text Available The Sonic Hedgehog (Shh signaling pathway is active during embryonic development in metazoans, and provides instructional cues necessary for proper tissue patterning. The pathway signal transducing component, Smoothened (Smo, is a G protein-coupled receptor (GPCR that has been demonstrated to signal through at least two effector routes. The first is a G protein–independent canonical route that signals to Gli transcriptional effectors to establish transcriptional programs specifying cell fate during early embryonic development. The second, commonly referred to as the noncanonical Smo signal, induces rapid, transcription-independent responses that are essential for establishing and maintaining distinct cell behaviors during development. Herein, we discuss contributions of this noncanonical route during embryonic development. We also highlight important open questions regarding noncanonical Smo signal route selection during development, and consider implications of noncanonical signal corruption in disease.

  18. High efficiency transfection of embryonic limb mesenchyme with plasmid DNA using square wave pulse electroporation and sucrose buffer.

    Science.gov (United States)

    Bobick, Brent E; Alexander, Peter G; Tuan, Rocky S

    2014-01-01

    Micromass cultures of primary embryonic limb mesenchyme are a valuable model system for studying cartilage formation in vitro. However, high efficiency introduction of plasmid DNA into this hard-to-transfect cell type typically results in considerable cell death and significantly impeded chondrogenesis when the cells are subsequently plated in high density micromass. Here, we describe a novel method in which square wave pulse electroporation of chick embryo wing bud mesenchyme suspended in protective sucrose buffer results in high efficiency transfection without substantially affecting micromass culture cell viability or chondrogenic differentiation potential. Furthermore, we show that this protocol can be employed, along with effector gene expression vectors, to generate observable changes in the amount of cartilage tissue formed in micromass, unlike lower efficiency, higher cytotoxicity techniques that require co-transfection of reporter plasmids to monitor changes in the extent of chondrogenesis and correct for differences in cell viability.

  19. Endolymphatic potassium of the chicken vestibule during embryonic development.

    Science.gov (United States)

    Masetto, Sergio; Zucca, Giampiero; Bottà, Luisa; Valli, Paolo

    2005-08-01

    The endolymph fills the lumen of the inner ear membranous labyrinth. Its ionic composition is unique in vertebrates as an extracellular fluid for its high-K(+)/low-Na(+) concentration. The endolymph is actively secreted by specialized cells located in the vestibular and cochlear epithelia. We have investigated the early phases of endolymph secretion by measuring the endolymphatic K(+) concentration in the chicken vestibular system during pre-hatching development. Measurements were done by inserting K(+)-selective microelectrodes in chicken embryo ampullae dissected at different developmental stages from embryonic day 9 up to embryonic day 21 (day of hatching). We found that the K(+) concentration is low (<10mM/L) up to embryonic day 11, afterward it increases steeply to reach a plateau level of about 140 mM/L at embryonic day 19--21. We have developed a short-term in vitro model of endolymph secretion by culturing vestibular ampullae dissected from embryonic day 11 chicken embryos for a few days. The preparation reproduced a double compartment system where the luminal K(+) concentration increased along with the days of culturing. This model could be important for (1) investigating the development of cellular mechanisms contributing to endolymph homeostasis and (2) testing compounds that influence those mechanisms.

  20. Are there factors preventing cancer development during embryonic life

    International Nuclear Information System (INIS)

    Einhorn, L.

    1983-01-01

    On the basis of the following literature observations, a hypothesis is advanced that the development of cancer is actively inhibited during embryonic life. Although the processes of cell differentiation and proliferation are - without comparison - most pronounced during embryonic life, cancer is rarely found in the newborn and is seldom a cause of neonatal death or spontaneous abortion. Attempts to induce cancer in early-stage animal embryos by irradiation or by transplacental chemical carcinogenesis have been unsuccessful, even when exposed animals have been observed throughout their lifetime. After the period of major organogenesis, however, the embryos become susceptible to carcinogenesis. In humans, the most common embryonic tumors arise in tissues which have an unusually late ongoing development and are still partly immature at or shortly before birth. For many human embryonic tumors the survival rates are higher, and spontaneous regression more frequent, in younger children, i.e. prognosis is age-dependent. Thus, although cancer generally appears in tissues capable of proliferation and differentiation, induction of malignancy in the developmentally most active tissues seems to be beset with difficulty. One possible explanation for this paradox could be that cancer is controlled by the regulators influencing development, regulators that are most active during embryonic life. (Auth.)

  1. Tetranectin is a novel marker for myogenesis during embryonic development, muscle regeneration, and muscle cell differentiation in vitro

    DEFF Research Database (Denmark)

    Wewer, U M; Iba, K; Durkin, M E

    1998-01-01

    cells in dystrophic mdx mice. Murine C2C12 myogenic cells and pluripotent embryonic stem cells can undergo muscle cell differentiation in vitro. Tetranectin is not expressed in the undifferentiated myogenic cells, but during the progression of muscle differentiation, tetranectin mRNA is induced......Tetranectin, a plasminogen-binding protein with a C-type lectin domain, is found in both serum and the extracellular matrix. In the present study we report that tetranectin is closely associated with myogenesis during embryonic development, skeletal muscle regeneration, and muscle cell......, and both cytoplasmic and cell surface tetranectin immunostaining become apparent. Finally, we demonstrate that while tetranectin mRNA is translated to a similar degree in developing limbs and lung, the protein does not seem to be tissue associated in the lung as it is in the limbs. This indicates...

  2. PTBP1 is required for embryonic development before gastrulation.

    Science.gov (United States)

    Suckale, Jakob; Wendling, Olivia; Masjkur, Jimmy; Jäger, Melanie; Münster, Carla; Anastassiadis, Konstantinos; Stewart, A Francis; Solimena, Michele

    2011-02-17

    Polypyrimidine-tract binding protein 1 (PTBP1) is an important cellular regulator of messenger RNAs influencing the alternative splicing profile of a cell as well as its mRNA stability, location and translation. In addition, it is diverted by some viruses to facilitate their replication. Here, we used a novel PTBP1 knockout mouse to analyse the tissue expression pattern of PTBP1 as well as the effect of its complete removal during development. We found evidence of strong PTBP1 expression in embryonic stem cells and throughout embryonic development, especially in the developing brain and spinal cord, the olfactory and auditory systems, the heart, the liver, the kidney, the brown fat and cartilage primordia. This widespread distribution points towards a role of PTBP1 during embryonic development. Homozygous offspring, identified by PCR and immunofluorescence, were able to implant but were arrested or retarded in growth. At day 7.5 of embryonic development (E7.5) the null mutants were about 5x smaller than the control littermates and the gap in body size widened with time. At mid-gestation, all homozygous embryos were resorbed/degraded. No homozygous mice were genotyped at E12 and the age of weaning. Embryos lacking PTBP1 did not display differentiation into the 3 germ layers and cavitation of the epiblast, which are hallmarks of gastrulation. In addition, homozygous mutants displayed malformed ectoplacental cones and yolk sacs, both early supportive structure of the embryo proper. We conclude that PTBP1 is not required for the earliest isovolumetric divisions and differentiation steps of the zygote up to the formation of the blastocyst. However, further post-implantation development requires PTBP1 and stalls in homozygous null animals with a phenotype of dramatically reduced size and aberration in embryonic and extra-embryonic structures.

  3. Dynamics of nuclear matrix proteome during embryonic development

    Indian Academy of Sciences (India)

    2011-07-08

    Jul 8, 2011 ... Embryonic development is a complex and dynamic process that involves spatiotemporal expression of genes in a highly coordinated manner. Multiple levels of nuclear architecture maintain the fidelity of gene expression programme. One of the components of nuclear architecture, which is believed to play ...

  4. Ovarian activity and early embryonic development in the rusty bat ...

    African Journals Online (AJOL)

    The reproductive pattern of the female rusty bat, Pipistrellus rusticus, was investigated by means of a histological examination of the ovarian follicles as well as early embryonic development. Bats were collected from two localities in Limpopo Province. Female rusty bats are seasonal monestrous breeders, initiating ...

  5. Embryonic development and hatchlings of Illex argentinus derived ...

    African Journals Online (AJOL)

    The embryonic and early post-hatching development of artificially fertilized eggs of Illex argentinus was observed at several temperatures from 8.5 to 23.2°C. During the fertilization procedure, oviducal gland jelly was added to eggs (about 1.0 mm long). Chorion expansion began 20 minutes after fertilization and continued ...

  6. Two human homeobox genes, c1 and c8: structure analysis and expression in embryonic development

    International Nuclear Information System (INIS)

    Simeone, A.; Mavilio, F.; Acampora, D.

    1987-01-01

    Two human cDNA clones (HHO.c1.95 and HHO.c8.5111) containing a homeobox region have been characterized, and the respective genomic regions have been partially analyzed. Expression of the corresponding genes, termed c1 and c8, was evaluated in different organs and body parts during human embryonic/fetal development. HHO.c1.95 apparently encodes a 217-amino acid protein containing a class I homeodomain that shares 60 out of 61 amino acid residues with the Antennapedia homeodomain of Drosophila melanogaster. HHO.c8.5111 encodes a 153-amino acid protein containing a homeodomains identical to that of the frog AC1 gene. Clones HHO.c1 and HHO.c8 detect by blot-hybridization one and two specific polyadenylylated transcripts, respectively. These are differentially expressed in spinal cord, backbone rudiments, limb buds (or limbs), heart, and skin of human embryos and early fetuses in the 5- to 9-week postfertilization period, thus suggesting that the c1 and c8 genes play a key role in a variety of developmental processes. Together, the results of the embryonic/fetal expression of c1 and c8 and those of two previously analyzed genes (c10 and c13) indicate a coherent pattern of expression of these genes in early human ontogeny

  7. Calcium metabolism in olive ridley turtle eggs during embryonic development.

    Science.gov (United States)

    Sahoo, G; Sahoo, R K; Mohanty-Hejmadi, P

    1998-09-01

    Analyses of calcium, magnesium, sulphur, potassium and phosphorus content of the eggshell, yolk-albumen and embryos of olive ridley turtle, Lepidochelys olivacea, have been carried out at various stages of embryonic development. Calcium is the major inorganic constituent in the egg (shell and yolk-albumen) and embryos. Other elements are present either in trace or in minute trace amounts. The egg contents (yolk and albumen) provide only 40% of the embryonic calcium requirement of the hatchling. The remaining 60% is provided by the eggshell. The eggshell also undergoes a similar reduction in its calcium content from laying to hatching. Elements other than calcium present in the yolk-albumen are sufficient for normal embryonic development. The movement of calcium from the eggshell to the embryo starts at about the 40th day of development at 29.5 degrees C. Birds, turtles and crocodiles use their eggshell as the secondary source of embryonic calcium requirement. This dependence on the eggshell varies in different groups which is highest in birds and lowest in crocodiles.

  8. Genetic Regulation of Embryological Limb Development with Relation to Congenital Limb Deformity in Humans

    OpenAIRE

    Barham, Guy; Clarke, Nicholas M. P.

    2008-01-01

    Over the last 15 years, great improvements in genetic engineering and genetic manipulation strategies have led to significant advances in the understanding of the genetics governing embryological limb development. This field of science continues to develop, and the complex genetic interactions and signalling pathways are still not fully understood. In this review we will discuss the roles of the principle genes involved in the three-dimensional patterning of the developing limb and will discu...

  9. Insulin-like growth factors in embryonic and fetal growth and skeletal development (Review).

    Science.gov (United States)

    Agrogiannis, Georgios D; Sifakis, Stavros; Patsouris, Efstratios S; Konstantinidou, Anastasia E

    2014-08-01

    The insulin-like growth factors (IGF)-I and -II have a predominant role in fetal growth and development. IGFs are involved in the proliferation, differentiation and apoptosis of fetal cells in vitro and the IGF serum concentration has been shown to be closely correlated with fetal growth and length. IGF transcripts and peptides have been detected in almost every fetal tissue from as early in development as pre‑implantation to the final maturation stage. Furthermore, IGFs have been demonstrated to be involved in limb morphogenesis. However, although ablation of Igf genes in mice resulted in growth retardation and delay in skeletal maturation, no impact on outgrowth and patterning of embryonic limbs was observed. Additionally, various molecular defects in the Igf1 and Igf1r genes in humans have been associated with severe intrauterine growth retardation and impaired skeletal maturation, but not with truncated limbs or severe skeletal dysplasia. The conflicting data between in vitro and in vivo observations with regard to bone morphogenesis suggests that IGFs may not be the sole trophic factors involved in fetal skeletal growth and that redundant mechanisms may exist in chondro- and osteogenesis. Further investigation is required in order to elucidate the functions of IGFs in skeletal development.

  10. Ca2+ signalling and early embryonic patterning during zebrafish development.

    Science.gov (United States)

    Webb, Sarah E; Miller, Andrew L

    2007-09-01

    1. It has been proposed that Ca2+ signalling, in the form of pulses, waves and steady gradients, may play a crucial role in key pattern-forming events during early vertebrate development. 2. With reference to the embryo of the zebrafish (Danio rerio), herein we review the Ca2+ transients reported from the cleavage to segmentation periods. This time-window includes most of the major pattern-forming events of early development, which transform a single-cell zygote into a complex multicellular embryo with established primary germ layers and body axes. 3. Data are presented to support our proposal that intracellular Ca2+ waves are an essential feature of embryonic cytokinesis and that propagating intercellular Ca2+ waves (both long and short range) may play a crucial role in: (i) the establishment of the embryonic periderm and the coordination of cell movements during epiboly, convergence and extension; (ii) the establishment of the basic embryonic axes and germ layers; and (iii) definition of the morphological boundaries of specific tissue domains and embryonic structures, including future organ anlagen. 4. The potential downstream targets of these Ca2+ transients are also discussed, as well as how they may integrate with other pattern-forming signalling pathways known to modulate early developmental events.

  11. Proteomic Analysis of Chicken Skeletal Muscle during Embryonic Development

    Directory of Open Access Journals (Sweden)

    Hongjia Ouyang

    2017-05-01

    Full Text Available Embryonic growth and development of skeletal muscle is a major determinant of muscle mass, and has a significant effect on meat production in chicken. To assess the protein expression profiles during embryonic skeletal muscle development, we performed a proteomics analysis using isobaric tags for relative and absolute quantification (iTRAQ in leg muscle tissues of female Xinghua chicken at embryonic age (E 11, E16, and 1-day post hatch (D1. We identified 3,240 proteins in chicken embryonic muscle and 491 of them were differentially expressed (fold change ≥ 1.5 or ≤ 0.666 and p < 0.05. There were 19 up- and 32 down-regulated proteins in E11 vs. E16 group, 238 up- and 227 down-regulated proteins in E11 vs. D1 group, and 13 up- and 5 down-regulated proteins in E16 vs. D1 group. Protein interaction network analyses indicated that these differentially expressed proteins were mainly involved in the pathway of protein synthesis, muscle contraction, and oxidative phosphorylation. Integrative analysis of proteome and our previous transcriptome data found 189 differentially expressed proteins that correlated with their mRNA level. The interactions between these proteins were also involved in muscle contraction and oxidative phosphorylation pathways. The lncRNA-protein interaction network found four proteins DMD, MYL3, TNNI2, and TNNT3 that are all involved in muscle contraction and may be lncRNA regulated. These results provide several candidate genes for further investigation into the molecular mechanisms of chicken embryonic muscle development, and enable us to better understanding their regulation networks and biochemical pathways.

  12. Embryonic development of Anodontites trapesialis (Lamarck, 1819) (Bivalvia: Mycetopodidae).

    Science.gov (United States)

    Silva-Souza, A T; Guardia-Felipi, P; Arrebola, N R

    2011-02-01

    The phases of embryonic development of Anodontites trapesialis lasidia are described for the first time. Adult specimens were obtained from two fish farms located in Londrina, Paraná, Brazil. The internal demibranchs of 120 individuals were studied using a routine histological technique; 70 of these carried eggs and/or larvae in the marsupium and were utilized for the description of the phases of embryonic development. The demibranchs of five specimens were evaluated by scanning electron microscopy to detail the morphology of the larvae. Five phases of development were established: phase I, corresponding to the initial stage of cleavage with the formation of apical cells; phase II, including the stages of the morula and blastula; phase III, where the gastrula forms; phase IV, where the larva formed is still inside the egg envelope; and phase V, where the lasidium can still be identified immediately after eclosion.

  13. Embryonic development of Anodontites trapesialis (Lamarck, 1819 (Bivalvia: Mycetopodidae

    Directory of Open Access Journals (Sweden)

    AT. Silva-Souza

    Full Text Available The phases of embryonic development of Anodontites trapesialis lasidia are described for the first time. Adult specimens were obtained from two fish farms located in Londrina, Paraná, Brazil. The internal demibranchs of 120 individuals were studied using a routine histological technique; 70 of these carried eggs and/or larvae in the marsupium and were utilized for the description of the phases of embryonic development. The demibranchs of five specimens were evaluated by scanning electron microscopy to detail the morphology of the larvae. Five phases of development were established: phase I, corresponding to the initial stage of cleavage with the formation of apical cells; phase II, including the stages of the morula and blastula; phase III, where the gastrula forms; phase IV, where the larva formed is still inside the egg envelope; and phase V, where the lasidium can still be identified immediately after eclosion.

  14. Calcium signalling during zebrafish embryonic development.

    Science.gov (United States)

    Webb, S E; Miller, A L

    2000-02-01

    Calcium signals appear throughout the first 24 hours of zebrafish development. These begin at egg activation, then continue to be generated throughout the subsequent zygote, cleavage, blastula, gastrula, and segmentation periods. They are thus associated with the major phases of pattern formation: cell proliferation, cell differentiation, axis determination, the generation of primary germ layers, the emergence of rudimentary organ systems, and therefore the establishment of the basic vertebrate body plan. When signals need to be transmitted across significant distances they take the form of waves, either intracellular waves when the cell size is large, or later in development when the cell size is reduced, intercellular waves. We will consider both types of calcium signals and their integration into signalling networks, and discuss their possible functions and developmental significance with regard to pattern formation. BioEssays 22:113-123, 2000. Copyright 2000 John Wiley & Sons, Inc.

  15. Factors that regulate embryonic gustatory development

    Directory of Open Access Journals (Sweden)

    Krimm Robin F

    2007-09-01

    Full Text Available Abstract Numerous molecular factors orchestrate the development of the peripheral taste system. The unique anatomy/function of the taste system makes this system ideal for understanding the mechanisms by which these factors function; yet the taste system is underutilized for this role. This review focuses on some of the many factors that are known to regulate gustatory development, and discusses a few topics where more work is needed. Some attention is given to factors that regulate epibranchial placode formation, since gustatory neurons are thought to be primarily derived from this region. Epibranchial placodes appear to arise from a pan-placodal region and a number of regulatory factors control the differentiation of individual placodes. Gustatory neuron differentiation is regulated by a series of transcription factors and perhaps bone morphongenic proteins (BMP. As neurons differentiate, they also proliferate such that their numbers exceed those in the adult, and this is followed by developmental death. Some of these cell-cycling events are regulated by neurotrophins. After gustatory neurons become post-mitotic, axon outgrowth occurs. Axons are guided by multiple chemoattractive and chemorepulsive factors, including semaphorins, to the tongue epithelium. Brain derived neurotrophic factor (BDNF, functions as a targeting factor in the final stages of axon guidance and is required for gustatory axons to find and innervate taste epithelium. Numerous factors are involved in the development of gustatory papillae including Sox-2, Sonic hedge hog and Wnt-β-catenin signaling. It is likely that just as many factors regulate taste bud differentiation; however, these factors have not yet been identified. Studies examining the molecular factors that regulate terminal field formation in the nucleus of the solitary tract are also lacking. However, it is possible that some of the factors that regulate geniculate ganglion development, outgrowth, guidance and

  16. Retinoic acid signalling in the development of the epidermis, the limbs and the secondary palate.

    Science.gov (United States)

    Mammadova, Aysel; Zhou, Huiqing; Carels, Carine E L; Von den Hoff, Johannes W

    2016-12-01

    Retinoic acid (RA), the active derivative of vitamin A, is one of the major regulators of embryonic development, including the development of the epidermis, the limbs and the secondary palate. In the embryo, RA levels are tightly regulated by the activity of RA synthesizing and degrading enzymes. Aberrant RA levels due to genetic variations in RA metabolism pathways contribute to congenital malformations in these structures. In vitro and in vivo studies provide considerable evidence on the effects of RA and its possible role in the development of the epidermis, the limbs and the secondary palate. In conjunction with other regulatory factors, RA seems to stimulate the development of the epidermis by inducing proliferation and differentiation of ectodermal cells into epidermal cells. In the limbs, the exact timing of RA location and level is crucial to initiate limb bud formation and to allow chondrogenesis and subsequent osteogenesis. In the secondary palate, the correct RA concentration is a key factor for mesenchymal cell proliferation during palatal shelf outgrowth, elevation and adhesion, and finally to allow bone formation in the hard palate. These findings are highly relevant to understanding the mechanism of RA signalling in development and in the aetiology of specific congenital diseases. Copyright © 2016 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  17. Effects of embryonic cyclosporine exposures on brain development and behavior.

    Science.gov (United States)

    Clift, Danielle E; Thorn, Robert J; Passarelli, Emily A; Kapoor, Mrinal; LoPiccolo, Mary K; Richendrfer, Holly A; Colwill, Ruth M; Creton, Robbert

    2015-04-01

    Cyclosporine, a calcineurin inhibitor, is successfully used as an immunosuppressant in transplant medicine. However, the use of this pharmaceutical during pregnancy is concerning since calcineurin is thought to play a role in neural development. The risk for human brain development is difficult to evaluate because of a lack of basic information on the sensitive developmental times and the potentially pleiotropic effects on brain development and behavior. In the present study, we use zebrafish as a model system to examine the effects of embryonic cyclosporine exposures. Early embryonic exposures reduced the size of the eyes and brain. Late embryonic exposures did not affect the size of the eyes or brain, but did lead to substantial behavioral defects at the larval stages. The cyclosporine-exposed larvae displayed a reduced avoidance response to visual stimuli, low swim speeds, increased resting, an increase in thigmotaxis, and changes in the average distance between larvae. Similar results were obtained with the calcineurin inhibitor FK506, suggesting that most, but not all, effects on brain development and behavior are mediated by calcineurin inhibition. Overall, the results show that cyclosporine can induce either structural or functional brain defects, depending on the exposure window. The observed functional brain defects highlight the importance of quantitative behavioral assays when evaluating the risk of developmental exposures. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Contributions of Noncanonical Smoothened Signaling During Embryonic Development

    OpenAIRE

    Pandit, Tanushree; Ogden, Stacey K.

    2017-01-01

    The Sonic Hedgehog (Shh) signaling pathway is active during embryonic development in metazoans, and provides instructional cues necessary for proper tissue patterning. The pathway signal transducing component, Smoothened (Smo), is a G protein-coupled receptor (GPCR) that has been demonstrated to signal through at least two effector routes. The first is a G protein–independent canonical route that signals to Gli transcriptional effectors to establish transcriptional programs specifying cell fa...

  19. Cadmium affects retinogenesis during zebrafish embryonic development

    International Nuclear Information System (INIS)

    Hen Chow, Elly Suk; Yu Hui, Michelle Nga; Cheng, Chi Wa; Cheng, Shuk Han

    2009-01-01

    Ocular malformations are commonly observed in embryos of aquatic species after exposure to toxicants. Using zebrafish embryos as the model organism, we showed that cadmium exposure from sphere stage (4 hpf) to end of segmentation stage (24 hpf) induced microphthalmia in cadmium-treated embryos. Embryos with eye defects were then assessed for visual abilities. Cadmium-exposed embryos were behaviorally blind, showing hyperpigmentation and loss of camouflage response to light. We investigated the cellular basis of the formation of the small eyes phenotype and the induction of blindness by studying retina development and retinotectal projections. Retinal progenitors were found in cadmium-treated embryos albeit in smaller numbers. The number of retinal ganglion cells (RGC), the first class of retinal cells to differentiate during retinogenesis, was reduced, while photoreceptor cells, the last batch of retinal neurons to differentiate, were absent. Cadmium also affected the propagation of neurons in neurogenic waves. The neurons remained in the ventronasal area and failed to spread across the retina. Drastically reduced RGC axons and disrupted optic stalk showed that the optic nerves did not extend from the retina beyond the chiasm into the tectum. Our data suggested that impairment in neuronal differentiation of the retina, disruption in RGC axon formation and absence of cone photoreceptors were the causes of microphthalmia and visual impairment in cadmium-treated embryos

  20. Wnts and wing: Wnt signaling in vertebrate limb development and musculoskeletal morphogenesis.

    Science.gov (United States)

    Yang, Yingzi

    2003-11-01

    In the past twenty years, secreted signaling molecules of the Wnt family have been found to play a central role in controlling embryonic development from hydra to human. In the developing vertebrate limb, Wnt signaling is required for limb bud initiation, early limb patterning (which is governed by several well-characterized signaling centers), and, finally, late limb morphogenesis events. Wnt ligands are unique, in that they can activate several different receptor-mediated signal transduction pathways. The most extensively studied Wnt pathway is the canonical Wnt pathway, which controls gene expression by stabilizing beta-catenin in regulating a diverse array of biological processes. Recently, more attention has been given to the noncanonical Wnt pathway, which is beta-catenin-independent. The noncanonical Wnt pathway signals through activating Ca(2+) flux, JNK activation, and both small and heterotrimeric G proteins, to induce changes in gene expression, cell adhesion, migration, and polarity. Abnormal Wnt signaling leads to developmental defects and human diseases affecting either tissue development or homeostasis. Further understanding of the biological function and signaling mechanism of Wnt signaling is essential for the development of novel preventive and therapeutic approaches of human diseases. This review provides a critical perspective on how Wnt signaling regulates different developmental processes. As Wnt signaling in tumor formation has been reviewed extensively elsewhere, this part is not included in the review of the clinical significance of Wnt signaling.

  1. Limb, tooth, beak: Three modes of development and evolutionary ...

    Indian Academy of Sciences (India)

    Here we compare the embryological processes that shape the vertebrate limb bud, the mammalian tooth and the avian beak. The implied notion of development in the standard evolutionary picture is met only in the case of the vertebrate limb, a single-primordium organ with morphostatic shaping, in which cells rearrange in ...

  2. EFFECTS OF ETHANOL AND HYDROGEN PEROXIDE ON MOUSE LIMB BUD MESENCHYME DIFFERENTIATION AND CELL DEATH

    Science.gov (United States)

    Many of the morphological defects associated with embryonic alcohol exposure are a result of cell death. During limb development, ethanol administration produces cell death in the limb and digital defects, including postaxial ectrodactyly. Because an accumulation of reactive oxyg...

  3. Embryonic cerebrospinal fluid in brain development: neural progenitor control.

    Science.gov (United States)

    Gato, Angel; Alonso, M Isabel; Martín, Cristina; Carnicero, Estela; Moro, José Antonio; De la Mano, Aníbal; Fernández, José M F; Lamus, Francisco; Desmond, Mary E

    2014-08-28

    Due to the effort of several research teams across the world, today we have a solid base of knowledge on the liquid contained in the brain cavities, its composition, and biological roles. Although the cerebrospinal fluid (CSF) is among the most relevant parts of the central nervous system from the physiological point of view, it seems that it is not a permanent and stable entity because its composition and biological properties evolve across life. So, we can talk about different CSFs during the vertebrate life span. In this review, we focus on the CSF in an interesting period, early in vertebrate development before the formation of the choroid plexus. This specific entity is called "embryonic CSF." Based on the structure of the compartment, CSF composition, origin and circulation, and its interaction with neuroepithelial precursor cells (the target cells) we can conclude that embryonic CSF is different from the CSF in later developmental stages and from the adult CSF. This article presents arguments that support the singularity of the embryonic CSF, mainly focusing on its influence on neural precursor behavior during development and in adult life.

  4. Uncoupled embryonic and extra-embryonic tissues compromise blastocyst development after somatic cell nuclear transfer.

    Directory of Open Access Journals (Sweden)

    Séverine A Degrelle

    Full Text Available Somatic cell nuclear transfer (SCNT is the most efficient cell reprogramming technique available, especially when working with bovine species. Although SCNT blastocysts performed equally well or better than controls in the weeks following embryo transfer at Day 7, elongation and gastrulation defects were observed prior to implantation. To understand the developmental implications of embryonic/extra-embryonic interactions, the morphological and molecular features of elongating and gastrulating tissues were analysed. At Day 18, 30 SCNT conceptuses were compared to 20 controls (AI and IVP: 10 conceptuses each; one-half of the SCNT conceptuses appeared normal while the other half showed signs of atypical elongation and gastrulation. SCNT was also associated with a high incidence of discordance in embryonic and extra-embryonic patterns, as evidenced by morphological and molecular "uncoupling". Elongation appeared to be secondarily affected; only 3 of 30 conceptuses had abnormally elongated shapes and there were very few differences in gene expression when they were compared to the controls. However, some of these differences could be linked to defects in microvilli formation or extracellular matrix composition and could thus impact extra-embryonic functions. In contrast to elongation, gastrulation stages included embryonic defects that likely affected the hypoblast, the epiblast, or the early stages of their differentiation. When taking into account SCNT conceptus somatic origin, i.e. the reprogramming efficiency of each bovine ear fibroblast (Low: 0029, Med: 7711, High: 5538, we found that embryonic abnormalities or severe embryonic/extra-embryonic uncoupling were more tightly correlated to embryo loss at implantation than were elongation defects. Alternatively, extra-embryonic differences between SCNT and control conceptuses at Day 18 were related to molecular plasticity (high efficiency/high plasticity and subsequent pregnancy loss. Finally

  5. Radiographic anatomy of developing canine pectoral limb

    International Nuclear Information System (INIS)

    Charjan, R.Y.; Bhamburkar, V.R.; Dalvi, R.S.; Banubakode, S.B.

    2006-01-01

    Age period for the appearance of the ossification centre that appear after birth in the limb bones of the dog were determined by radiography, at set intervals in 3 German Shepherd, Pomeranian and Non-descript. The ossification centres appeared in the same chronological order, but the ages at which they appear, showed variation

  6. Salamander limb development: integrating genes, morphology, and fossils.

    Science.gov (United States)

    Fröbisch, Nadia B; Shubin, Neil H

    2011-05-01

    The development of the tetrapod limb during skeletogenesis follows a highly conservative pattern characterized by a general proximo-distal progression in the establishment of skeletal elements and a postaxial polarity in digit development. Salamanders represent the only exception to this pattern and display an early establishment of distal autopodial structures, specifically the basale commune, an amalgamation of distal carpal and tarsal 1 and 2, and a distinct preaxial polarity in digit development. This deviance from the conserved tetrapod pattern has resulted in a number of hypotheses to explain its developmental basis and evolutionary history. Here we summarize the current knowledge of salamander limb development under consideration of the fossil record to provide a deep time perspective of this evolutionary pathway and highlight what data will be needed in the future to gain a better understanding of salamander limb development specifically and tetrapod limb development and evolution more broadly. Copyright © 2011 Wiley-Liss, Inc.

  7. The 'ventral organs' of Pycnogonida (Arthropoda) are neurogenic niches of late embryonic and post-embryonic nervous system development.

    Science.gov (United States)

    Brenneis, Georg; Scholtz, Gerhard

    2014-01-01

    Early neurogenesis in arthropods has been in the focus of numerous studies, its cellular basis, spatio-temporal dynamics and underlying genetic network being by now comparably well characterized for representatives of chelicerates, myriapods, hexapods and crustaceans. By contrast, neurogenesis during late embryonic and/or post-embryonic development has received less attention, especially in myriapods and chelicerates. Here, we apply (i) immunolabeling, (ii) histology and (iii) scanning electron microscopy to study post-embryonic ventral nerve cord development in Pseudopallene sp., a representative of the sea spiders (Pycnogonida), the presumable sister group of the remaining chelicerates. During early post-embryonic development, large neural stem cells give rise to additional ganglion cell material in segmentally paired invaginations in the ventral ectoderm. These ectodermal cell regions - traditionally designated as 'ventral organs' - detach from the surface into the interior and persist as apical cell clusters on the ventral ganglion side. Each cluster is a post-embryonic neurogenic niche that features a tiny central cavity and initially still houses larger neural stem cells. The cluster stays connected to the underlying ganglionic somata cortex via an anterior and a posterior cell stream. Cell proliferation remains restricted to the cluster and streams, and migration of newly produced cells along the streams seems to account for increasing ganglion cell numbers in the cortex. The pycnogonid cluster-stream-systems show striking similarities to the life-long neurogenic system of decapod crustaceans, and due to their close vicinity to glomerulus-like neuropils, we consider their possible involvement in post-embryonic (perhaps even adult) replenishment of olfactory neurons - as in decapods. An instance of a potentially similar post-embryonic/adult neurogenic system in the arthropod outgroup Onychophora is discussed. Additionally, we document two transient posterior

  8. The 'ventral organs' of Pycnogonida (Arthropoda are neurogenic niches of late embryonic and post-embryonic nervous system development.

    Directory of Open Access Journals (Sweden)

    Georg Brenneis

    Full Text Available Early neurogenesis in arthropods has been in the focus of numerous studies, its cellular basis, spatio-temporal dynamics and underlying genetic network being by now comparably well characterized for representatives of chelicerates, myriapods, hexapods and crustaceans. By contrast, neurogenesis during late embryonic and/or post-embryonic development has received less attention, especially in myriapods and chelicerates. Here, we apply (i immunolabeling, (ii histology and (iii scanning electron microscopy to study post-embryonic ventral nerve cord development in Pseudopallene sp., a representative of the sea spiders (Pycnogonida, the presumable sister group of the remaining chelicerates. During early post-embryonic development, large neural stem cells give rise to additional ganglion cell material in segmentally paired invaginations in the ventral ectoderm. These ectodermal cell regions - traditionally designated as 'ventral organs' - detach from the surface into the interior and persist as apical cell clusters on the ventral ganglion side. Each cluster is a post-embryonic neurogenic niche that features a tiny central cavity and initially still houses larger neural stem cells. The cluster stays connected to the underlying ganglionic somata cortex via an anterior and a posterior cell stream. Cell proliferation remains restricted to the cluster and streams, and migration of newly produced cells along the streams seems to account for increasing ganglion cell numbers in the cortex. The pycnogonid cluster-stream-systems show striking similarities to the life-long neurogenic system of decapod crustaceans, and due to their close vicinity to glomerulus-like neuropils, we consider their possible involvement in post-embryonic (perhaps even adult replenishment of olfactory neurons - as in decapods. An instance of a potentially similar post-embryonic/adult neurogenic system in the arthropod outgroup Onychophora is discussed. Additionally, we document two

  9. An embryonic staging table for in ovo development of Eublepharis macularius, the leopard gecko.

    Science.gov (United States)

    Wise, Patrick A D; Vickaryous, Matthew K; Russell, Anthony P

    2009-08-01

    Squamates constitute a major vertebrate radiation, representing almost one-third of all known amniotes. Although speciose and morphologically diverse, they remain poorly represented in developmental studies. Here, we present an embryonic staging table of in ovo development for the basal gekkotan Eublepharis macularius (the leopard gecko) and advocate this species as a laboratory-appropriate developmental model. E. macularius, is a hardy and tractable species of relatively large body size (with concomitantly relatively large eggs and embryos), that is widely available and easy to maintain and propagate. Additionally, E. macularius displays a body plan appropriate to the study of the plesiomorphic quadrupedal condition of early pentadactylous terrestrial amniotes. Although not unexpected, it is worth noting that the morphological events characterizing limb development in E. macularius are comparable with those described for the avian Gallus gallus. Therefore, E. macularius holds great promise as a model for developmental studies focusing on pentadactyly and the formation of digits. Furthermore, it is also attractive as a developmental model because it demonstrates temperature-dependent sex determination. The staging table presented herein is based on an all-female series and represents the entire 52 day in ovo period. Overall, embryogenesis of E. macularius is similar to that of other squamates in terms of developmental stage attained at the time of oviposition, patterns of limb and pharyngeal arch development, and features of the appearance of scalation and pigmentation, indicative of a conserved developmental program. (c) 2009 Wiley-Liss, Inc.

  10. Can physics help to explain embryonic development? An overview.

    Science.gov (United States)

    Fleury, V

    2013-10-01

    Recent technical advances including digital imaging and particle image velocimetry can be used to extract the full range of embryonic movements that constitute the instantaneous 'morphogenetic fields' of a developing animal. The final shape of the animal results from the sum over time (integral) of the movements that make up the velocity fields of all the tissue constituents. In vivo microscopy can be used to capture the details of vertebrate development at the earliest embryonic stages. The movements thus observed can be quantitatively compared to physical models that provide velocity fields based on simple hypotheses about the nature of living matter (a visco-elastic gel). This approach has cast new light on the interpretation of embryonic movement, folding, and organisation. It has established that several major discontinuities in development are simple physical changes in boundary conditions. In other words, with no change in biology, the physical consequences of collisions between folds largely explain the morphogenesis of the major structures (such as the head). Other discontinuities result from changes in physical conditions, such as bifurcations (changes in physical behaviour beyond specific yield points). For instance, beyond a certain level of stress, a tissue folds, without any new gene being involved. An understanding of the physical features of movement provides insights into the levers that drive evolution; the origin of animals is seen more clearly when viewed under the light of the fundamental physical laws (Newton's principle, action-reaction law, changes in symmetry breaking scale). This article describes the genesis of a vertebrate embryo from the shapeless stage (round mass of tissue) to the development of a small, elongated, bilaterally symmetric structure containing vertebral precursors, hip and shoulder enlarges, and a head. Copyright © 2013. Published by Elsevier Masson SAS.

  11. Expression of smoothened in mouse embryonic maxillofacial development.

    Science.gov (United States)

    Du, J; Fan, Z; Ma, X; Wu, Y; Liu, S; Gao, Y; Shen, Y; Fan, M; Wang, S

    2012-04-01

    Hedgehog (Hh) signaling plays many key roles in the development of Drosophila and vertebrate embryos including regulation of craniofacial development. The seven-transmembrane protein, smoothened (Smo) transduces the Hh signal across the plasma membrane as an essential receptor of PTCHED1/2. There are few studies that evaluate the detailed expression of Smo in mouse embryonic craniofacial development. We investigated the expression patterns of Smo during murine embryonic craniofacial development using in situ hybridization (ISH), studies of whole-mounts and sections, immunohistochemistry, quantitative real time PCR, and Western blot analysis. We found that Smo mRNA was expressed in the face of mouse embryos at 11 and 12.5 days post coitum (dpc). After 13.5 dpc, the expression decreased to a low level and was faintly detected after birth. Smo protein could be detected also in embryos at 11, 12.5, and 14.5 dpc. After 15.5 dpc, the expression was very faint and paralleled the gene expression studies. No expression was detected in whisker follicle during facial development and faint signal was detected in Meckel's cartilage. These findings concerning Smo expression should guide further investigation of sonic Hh signaling pathway gene function during maxillofacial development.

  12. The NF-κB family: Key players during embryonic development and HSC emergence.

    Science.gov (United States)

    Espín-Palazón, Raquel; Traver, David

    2016-07-01

    The nuclear factor-κB (NF-κB) family is a crucial transcription factor group known mainly for its role in the regulation of the immune system and its response to infection in vertebrates. The signaling pathway leading to NF-κB activation and translocation to the nucleus to exert its function as a transcription factor is well conserved among Kingdom Animalia, which has helped to elucidate other roles that NF-κB plays in other biological contexts such as developmental biology. The manipulation of NF-κB members in a diverse range of animal models results in severe developmental defects during embryogenesis, very often leading to embryonic lethality. Defects include dorsal-ventral patterning and limb, liver, skin, lung, neural, notochord, muscle, skeletal, and hematopoietic defects. Here, we recapitulate the research that has been done to address the role that NF-κB plays during embryonic development, in particular to emphasize its recently discovered role in the specification of hematopoietic stem cells (HSCs), the foundation of the hematopoietic system in vertebrates. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

  13. Egg size, embryonic development time and ovoviviparity in Drosophila species.

    Science.gov (United States)

    Markow, T A; Beall, S; Matzkin, L M

    2009-02-01

    Lengths, widths and volumes of eggs from 11 species of Drosophila whose genomes have been fully sequenced exhibit significant variation that is not explained by their phylogenetic relationships. Furthermore, egg size differences are unrelated to embryonic development time in these species. In addition, two of the species, Drosophila sechellia and, to a lesser degree, D. yakuba, both ecological specialists, exhibit ovoviviparity, suggesting that female control over oviposition in these species differs from what is observed in D. melanogaster. The interspecific differences in these reproductive characters, coupled with the availability of whole genome sequences for each, provide an unprecedented opportunity to examine their evolution.

  14. Localization in Oogenesis of Maternal Regulators of Embryonic Development.

    Science.gov (United States)

    Escobar-Aguirre, Matias; Elkouby, Yaniv M; Mullins, Mary C

    2017-01-01

    Cell polarity generates intracellular asymmetries and functional regionalization in tissues and morphogenetic processes. Cell polarity in development often relies on mechanisms of RNA localization to specific subcellular domains to define the identity of future developing tissues. The totipotent egg of most animals illustrates in a grand way the importance of cell polarity and RNA localization in regulating multiple crucial developmental events. The polarization of the egg arises during its development in oogenesis. RNAs localize asymmetrically in the early oocyte defining its animal-vegetal (AV) axis, which upon further elaboration in mid- and late-oogenesis stages produces a mature egg with specific localized factors along its AV axis. These localized factors will define the future anterior-posterior (AP) and dorsal-ventral (DV) axes of the embryo. Furthermore, AV polarity confines germ cell determinants to the vegetal pole, from where they redistribute to the cleavage furrows of the 2- and 4-cell stage embryo, ultimately specifying the primordial germ cells (PGCs). The sperm entry region during fertilization is also defined by the AV axis. In frogs and fish, sperm enters through the animal pole, similar to the mouse where it enters predominantly in the animal half. Thus, AV polarity establishment and RNA localization are involved in all the major events of early embryonic development. In this chapter, we will review the RNA localization mechanisms in vertebrate oocytes that are key to embryonic patterning, referring to some of the groundbreaking studies in frog oocytes and incorporating the current genetic evidence from the zebrafish.

  15. Peculiarities of Embryonic and Post-Embryonic Development of Оesophagostomum dentatum (Nematoda, Strongylidae Larvae Cultured in Vitro

    Directory of Open Access Journals (Sweden)

    Yevstafieva V. А.

    2017-02-01

    Full Text Available Morphometric peculiarities of the development of Оesophagostomum dentatum Rudolphi, 1803 from egg to infective larva were studied under laboratory conditions at various temperatures. The determined optimum temperature for embryonic and post-embryonic development of О. dentatum larvae from domestic pig (Sus scrofa domesticus Linnaeus, 1758 is 22 °С. At this temperature, 81 % of larvae develop to the third stage (L3 on the 10th day. Temperatures of 24 °С and 20 °С are less favorable for the development of the nematode, at those temperatures only 67 and 63 % of larvae, respectively, reached infective stage by the 10th day of cultivation. Embryonic development of О. dentatum eggs is characterized by their lengthening (by 8.87-9.50 %, р < 0.01 and widening (by 6.77-9.35 %, р < 0.05-0.01, and post-embryonic larval development is associated with lengthening (by 4.59-17.33 %, р < 0.01-0.001.

  16. Dual effects of fluoxetine on mouse early embryonic development

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang-Woon [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of); Department of Obstetrics and Gynecology, Samsung Changwon Hospital, Sungkyunkwan University, Changwon 630-723 (Korea, Republic of); Choe, Changyong [National Institute of Animal Science, RDA, Cheonan 330-801 (Korea, Republic of); Kim, Eun-Jin [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of); Lee, Jae-Ik [Department of Obstetrics and Gynecology, Gyeongsang National University Hospital, Jinju 660-702 (Korea, Republic of); Yoon, Sook-Young [Fertility Center of CHA Gangnam Medical Center, CHA University, Seoul 135-081 (Korea, Republic of); Cho, Young-Woo; Han, Sunkyu; Tak, Hyun-Min; Han, Jaehee [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of); Kang, Dawon, E-mail: dawon@gnu.ac.kr [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of)

    2012-11-15

    Fluoxetine, a selective serotonin reuptake inhibitor, regulates a variety of physiological processes, such as cell proliferation and apoptosis, in mammalian cells. Little is known about the role of fluoxetine in early embryonic development. This study was undertaken to investigate the effect of fluoxetine during mouse early embryonic development. Late two-cell stage embryos (2-cells) were cultured in the presence of various concentrations of fluoxetine (1 to 50 μM) for different durations. When late 2-cells were incubated with 5 μM fluoxetine for 6 h, the percentage that developed into blastocysts increased compared to the control value. However, late 2-cells exposed to fluoxetine (5 μM) over 24 h showed a reduction in blastocyst formation. The addition of fluoxetine (5 μM) together with KN93 or KN62 (calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitors) failed to increase blastocyst formation. Fluoxetine treatment inhibited TREK-1 and TREK-2, members of the two-pore domain K{sup +} channel family expressed in mouse embryos, activities, indicating that fluoxetine-induced membrane depolarization in late 2-cells might have resulted from TREK inhibition. In addition, long-term exposure to fluoxetine altered the TREK mRNA expression levels. Furthermore, injection of siRNA targeting TREKs significantly decreased blastocyst formation by ∼ 30% compared to injection of scrambled siRNA. Long-term exposure of fluoxetine had no effect on blastocyst formation of TREK deficient embryos. These results indicate that low-dose and short-term exposures of late 2-cells to fluoxetine probably increase blastocyst formation through activation of CaMKII-dependent signal transduction pathways, whereas long-term exposure decreases mouse early embryonic development through inhibition of TREK channel gating. Highlights: ► Short-term exposure of 2-cells to fluoxetine enhances mouse blastocyst formation. ► The enhancive effect of fluoxetine is resulted from Ca

  17. Differential effects of high and low strength magnetic fields on mouse embryonic development and vasculogenesis of embryonic stem cells.

    Science.gov (United States)

    Bekhite, Mohamed M; Finkensieper, Andreas; Abou-Zaid, Fouad A; El-Shourbagy, Ibrahim K; El-Fiky, Nabil K; Omar, Khaled M; Sauer, Heinrich; Wartenberg, Maria

    2016-10-01

    Man-made magnetic fields (MFs) may exert adverse effects on mammalian embryonic development. Herein, we analysed the effect of 10mT 50Hz sinusoidal (AC) or static (DC) MFs versus 1mT MFs on embryonic development of mice. Exposure for 20days during gestation to 10mT MFs increased resorptions and dead fetuses, decreased crown-rump length and fresh weight, reduced blood vessel differentiation and caused histological changes, accompanied with diminished vascular endothelial growth factor (VEGF) protein expression in several organs. In embryonic stem (ES) cell-derived embryoid bodies exposure towards 10mT MFs increased reactive oxygen species (ROS), decreased vascular marker as well as VEGF expression and enhanced apoptosis. In conclusion, our combined data from in vivo and in vitro experiments identified VEGF as an important mediator during embryonic development that can be influenced by high strength MFs, which in consequence leads to severe abnormalities in fetus organs and blood vessel formation. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Acetylcholinesterase Regulates Skeletal In Ovo Development of Chicken Limbs by ACh-Dependent and -Independent Mechanisms.

    Science.gov (United States)

    Spieker, Janine; Ackermann, Anica; Salfelder, Anika; Vogel-Höpker, Astrid; Layer, Paul G

    2016-01-01

    Formation of the vertebrate limb presents an excellent model to analyze a non-neuronal cholinergic system (NNCS). Here, we first analyzed the expression of acetylcholinesterase (AChE) by IHC and of choline acetyltransferase (ChAT) by ISH in developing embryonic chicken limbs (stages HH17-37). AChE outlined formation of bones, being strongest at their distal tips, and later also marked areas of cell death. At onset, AChE and ChAT were elevated in two organizing centers of the limb anlage, the apical ectodermal ridge (AER) and zone of polarizing activity (ZPA), respectively. Thereby ChAT was expressed shortly after AChE, thus strongly supporting a leading role of AChE in limb formation. Then, we conducted loss-of-function studies via unilateral implantation of beads into chicken limb anlagen, which were soaked in cholinergic components. After varying periods, the formation of cartilage matrix and of mineralizing bones was followed by Alcian blue (AB) and Alizarin red (AR) stainings, respectively. Both acetylcholine (ACh)- and ChAT-soaked beads accelerated bone formation in ovo. Notably, inhibition of AChE by BW284c51, or by the monoclonal antibody MAB304 delayed cartilage formation. Since bead inhibition of BChE was mostly ineffective, an ACh-independent action during BW284c51 and MAB304 inhibition was indicated, which possibly could be due to an enzymatic side activity of AChE. In conclusion, skeletogenesis in chick is regulated by an ACh-dependent cholinergic system, but to some extent also by an ACh-independent aspect of the AChE protein.

  19. Acetylcholinesterase Regulates Skeletal In Ovo Development of Chicken Limbs by ACh-Dependent and -Independent Mechanisms.

    Directory of Open Access Journals (Sweden)

    Janine Spieker

    Full Text Available Formation of the vertebrate limb presents an excellent model to analyze a non-neuronal cholinergic system (NNCS. Here, we first analyzed the expression of acetylcholinesterase (AChE by IHC and of choline acetyltransferase (ChAT by ISH in developing embryonic chicken limbs (stages HH17-37. AChE outlined formation of bones, being strongest at their distal tips, and later also marked areas of cell death. At onset, AChE and ChAT were elevated in two organizing centers of the limb anlage, the apical ectodermal ridge (AER and zone of polarizing activity (ZPA, respectively. Thereby ChAT was expressed shortly after AChE, thus strongly supporting a leading role of AChE in limb formation. Then, we conducted loss-of-function studies via unilateral implantation of beads into chicken limb anlagen, which were soaked in cholinergic components. After varying periods, the formation of cartilage matrix and of mineralizing bones was followed by Alcian blue (AB and Alizarin red (AR stainings, respectively. Both acetylcholine (ACh- and ChAT-soaked beads accelerated bone formation in ovo. Notably, inhibition of AChE by BW284c51, or by the monoclonal antibody MAB304 delayed cartilage formation. Since bead inhibition of BChE was mostly ineffective, an ACh-independent action during BW284c51 and MAB304 inhibition was indicated, which possibly could be due to an enzymatic side activity of AChE. In conclusion, skeletogenesis in chick is regulated by an ACh-dependent cholinergic system, but to some extent also by an ACh-independent aspect of the AChE protein.

  20. Histone demethylase JMJD5 is essential for embryonic development

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Sangphil [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 (United States); Janknecht, Ralf, E-mail: ralf-janknecht@ouhsc.edu [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104 (United States)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Histone demethylase JMJD5 is essential for embryogenesis. Black-Right-Pointing-Pointer Transcription of tumor suppressor p53 is upregulated in JMJD5 knockout embryos. Black-Right-Pointing-Pointer JMJD5 may antagonize p53-dependent growth inhibition and apoptosis. Black-Right-Pointing-Pointer JMJD5 is overexpressed in leukemias and breast cancer. -- Abstract: Histone lysine methylation is pivotal in regulating chromatin structure and thus profoundly affects the transcriptome. JMJD5 (jumonji C domain-containing 5) is a histone demethylase that specifically removes methyl moieties from dimethylated lysine 36 on histone H3 and exerts a pro-proliferative effect on breast cancer cells. Here, we generated JMJD5 knockout mice in order to study the physiological significance of this enzyme. Whereas heterozygous knockout mice displayed no overt phenotype, homozygous JMJD5 knockouts died around day 10 of embryonal development. JMJD5{sup -/-} embryos showed delayed development already at E8.5 and were actively resorbed at E10.5. While strong JMJD5 expression was observed only in the yolk sac at E8.5, JMJD5 was robustly expressed in E10.5 embryos at several sites, including the heart and eye. Lack of JMJD5 resulted in transcriptional upregulation of the tumor suppressor p53. Concurrently, the cell cycle inhibitor p21 and the pro-apoptotic molecule Noxa, both of which are prominent p53 target genes, became strongly upregulated in JMJD5{sup -/-} embryos. Collectively, our data indicate that JMJD5 is essential during embryonal development and a repressor of p53 expression. The latter suggests that JMJD5 has oncogenic activity and accordingly JMJD5 is upregulated in leukemias and breast cancer.

  1. A computational clonal analysis of the developing mouse limb bud.

    Directory of Open Access Journals (Sweden)

    Luciano Marcon

    Full Text Available A comprehensive spatio-temporal description of the tissue movements underlying organogenesis would be an extremely useful resource to developmental biology. Clonal analysis and fate mappings are popular experiments to study tissue movement during morphogenesis. Such experiments allow cell populations to be labeled at an early stage of development and to follow their spatial evolution over time. However, disentangling the cumulative effects of the multiple events responsible for the expansion of the labeled cell population is not always straightforward. To overcome this problem, we develop a novel computational method that combines accurate quantification of 2D limb bud morphologies and growth modeling to analyze mouse clonal data of early limb development. Firstly, we explore various tissue movements that match experimental limb bud shape changes. Secondly, by comparing computational clones with newly generated mouse clonal data we are able to choose and characterize the tissue movement map that better matches experimental data. Our computational analysis produces for the first time a two dimensional model of limb growth based on experimental data that can be used to better characterize limb tissue movement in space and time. The model shows that the distribution and shapes of clones can be described as a combination of anisotropic growth with isotropic cell mixing, without the need for lineage compartmentalization along the AP and PD axis. Lastly, we show that this comprehensive description can be used to reassess spatio-temporal gene regulations taking tissue movement into account and to investigate PD patterning hypothesis.

  2. Thalidomide Induces Limb Anomalies by PTEN Stabilization, Akt Suppression, and Stimulation of Caspase-Dependent Cell Death▿

    OpenAIRE

    Knobloch, Jürgen; Schmitz, Ingo; Götz, Katrin; Schulze-Osthoff, Klaus; Rüther, Ulrich

    2007-01-01

    Thalidomide, a drug used for the treatment of multiple myeloma and inflammatory diseases, is also a teratogen that causes birth defects, such as limb truncations and microphthalmia, in humans. Thalidomide-induced limb truncations result from increased cell death during embryonic limb development and consequential disturbance of limb outgrowth. Here we demonstrate in primary human embryonic cells and in the chicken embryo that thalidomide-induced signaling through bone morphogenetic proteins (...

  3. Smoc2 modulates embryonic myelopoiesis during zebrafish development.

    Science.gov (United States)

    Mommaerts, Hendrik; Esguerra, Camila V; Hartmann, Ursula; Luyten, Frank P; Tylzanowski, Przemko

    2014-11-01

    SMOC2 is a member of the BM-40 (SPARC) family of matricellular proteins, reported to influence signaling in the extracellular compartment. In mice, Smoc2 is expressed in many different tissues and was shown to enhance the response to angiogenic growth factors, mediate cell adhesion, keratinocyte migration, and metastasis. Additionally, SMOC2 is associated with vitiligo and craniofacial and dental defects. The function of Smoc2 during early zebrafish development has not been determined to date. In pregastrula zebrafish embryos, smoc2 is expressed ubiquitously. As development progresses, the expression pattern becomes more anteriorly restricted. At the onset of blood cell circulation, smoc2 morphants presented a mild ventralization of posterior structures. Molecular analysis of the smoc2 morphants indicated myelopoietic defects in the rostral blood islands during segmentation stages. Hemangioblast development and further specification of the myeloid progenitor cells were shown to be impaired. Additional experiments indicated that Bmp target genes were down-regulated in smoc2 morphants. Our findings reveal that Smoc2 is an essential player in the development of myeloid cells of the anterior lateral plate mesoderm during embryonic zebrafish development. Furthermore, our data show that Smoc2 affects the transcription of Bmp target genes without affecting initial dorsoventral patterning or mesoderm development. Copyright © 2014 Wiley Periodicals, Inc.

  4. Review and experimental evaluation of the embryonic development and evolutionary history of flipper development and hyperphalangy in dolphins (Cetacea: Mammalia).

    Science.gov (United States)

    Cooper, Lisa Noelle; Sears, Karen E; Armfield, Brooke A; Kala, Bhavneet; Hubler, Merla; Thewissen, J G M

    2018-01-01

    Cetaceans are the only mammals to have evolved hyperphalangy, an increase in the number of phalanges beyond the mammalian plesiomorphic condition of three phalanges per digit. In this study, cetaceans were used as a novel model to review previous studies of mammalian hyperphalangy and contribute new experimental evidence as to the molecular origins of this phenotype in embryos of the pantropical spotted dolphin (Stenella attenuata). Results show embryos of dolphins, mice, and pigs share similar spatiotemporal patterns of signaling proteins known to shape limbs of mammals (e.g., FGF8, BMP2/4, WNT, GREM). However, fetal dolphins differ in that their interdigital tissues are retained, instead of undergoing apoptosis, and that multiple waves of interdigital signals likely contribute to the patterning of supernumerary joints and phalanges in adjacent digits. Integration of fossil and experimental evidence suggests that the presence of interdigital webbing within the fossils of semi-aquatic cetaceans, recovered from the Eocene Epoch (49Ma), was probably the result of BMP-antagonists counteracting interdigital apoptosis during embryonic limb development. Modifications to signals originating in these interdigital tissues likely contributed to the origin of an incipient form of hyperphalangy in obligatorily aquatic cetaceans about 35Ma. Finally, an extreme form of hyperphalangy, with six or more phalanges per digit, evolved independently in rorqual whales (Balaenopteridae) and delphinids, and was probably associated with a wave of signaling within the interdigital tissues. © 2017 Wiley Periodicals, Inc.

  5. The role of the pupal determinant broad during embryonic development of a direct-developing insect

    Science.gov (United States)

    Rynerson, Melody R.; Truman, James W.; Riddiford, Lynn M.

    2010-01-01

    Metamorphosis is one of the most common, yet dramatic of life history strategies. In insects, complete metamorphosis with morphologically distinct larval stages arose from hemimetabolous ancestors that were more direct developing. Over the past century, several ideas have emerged that suggest the holometabolous pupa is developmentally homologous to the embryonic stages of the hemimetabolous ancestor. Other theories consider the pupal stage to be a modification of a hemimetabolous nymph. To address this question, we have isolated an ortholog of the pupal determinant, broad (br), from the hemimetabolous milkweed bug and examined its role during embryonic development. We show that Oncopeltus fasciatus br (Of'br) is expressed in two phases. The first occurs during germ band invagination and segmentation when Of'br is expressed ubiquitously in the embryonic tissues. The second phase of Of'br expression appears during the pronymphal phase of embryogenesis and persists through nymphal differentiation to decline just before hatching. Knock-down of Of'br transcripts results in defects that range from posterior truncations in the least-affected phenotypes to completely fragmented embryonic tissues in the most severe cases. Analysis of the patterning genes engrailed and hunchback reveal loss of segments and a failure in neural differentiation after Of'br depletion. Finally, we show that br is constitutively expressed during embyrogenesis of the ametabolous firebrat, Thermobia domestica. This suggests that br expression is prominent during embryonic development of ametabolous and hemimetabolous insects but was lost with the emergence of the completely metamorphosing insects. PMID:20127251

  6. ECM modulated early kidney development in embryonic organ culture.

    Science.gov (United States)

    Sebinger, David D R; Ofenbauer, Andreas; Gruber, Petra; Malik, Susann; Werner, Carsten

    2013-09-01

    The use of exogenous signals is gaining importance in renal regenerative therapies. We wanted to explore the role of extracellular matrix (ECM) constituents on renal structure formation during renal organogenesis. We used a recently established organ culture setup to expose embryonic kidney rudiments directly to a large set of surface-immobilized or dissolved ECM molecules and growth factors. Organ culture was also performed on immobilized adult kidney ECM extracts and on reactive polymer films without any biomolecular components. The applied conditions resulted in distinct differences of organ phenotypes, underlining the multifaceted role of exogenous signals during kidney development. Specific ECM components, including collagen I and laminin, supported nephronal and tubular structure formation of the developing organ. ECM biopolymers, e.g. hyaluronic acid, were found to determine the fate of developing explants in a concentration- and molecular weight-dependent manner. The organ culture system used was an effective and robust means to identify exogenous signals that direct kidney development. This system can provide valuable insight for future regenerative therapies of kidney diseases. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. The many lives of SHH in limb development and evolution.

    Science.gov (United States)

    Lopez-Rios, Javier

    2016-01-01

    The SHH signaling pathway is essential for proper formation of the limb skeleton, as is required for the survival and expansion of distal chondrogenic progenitor cells. At the same time, SHH is important to specify digit identities along the anterior-posterior axis. Upon gain or loss of activity of the SHH pathway, bones are gained, lost or malformed, and such deregulation underlies the aetiology of various human congenital limb defects. Likewise, accumulating evidence suggests that evolutionary tampering with SHH signaling underlies the morphological diversification of the tetrapod appendicular skeleton. This review summarizes the roles of the SHH pathway in the context of limb development and evolution and incorporates recent evidence into a mechanistic view of how the positioning of digit condensations is integrated with the specification of distinct bone morphologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Use of a virtual integrated environment in prosthetic limb development and phantom limb pain.

    Science.gov (United States)

    Alphonso, Aimee L; Monson, Brett T; Zeher, Michael J; Armiger, Robert S; Weeks, Sharon R; Burck, J M; Moran, C; Davoodie, R; Loeb, G; Pasquina, Paul F; Tsao, Jack W

    2012-01-01

    Patients face two major difficulties following limb loss: phantom limb pain (PLP) in the residual limb and limited functionality in the prosthetic limb. Many studies have focused on decreasing PLP with mirror therapy, yet few have examined the same visual ameliorating effect with a virtual or prosthetic limb. Our study addresses the following key questions: (1) does PLP decrease through observation of a 3D limb in a virtual integration environment (VIE) and (2) can consistent surface electromyography (sEMG) signals from the VIE drive an advanced modular prosthetic limb (MPL)? Recorded signals from the residual limb were correlated to the desired motion of the phantom limb, and changes in PLP were scored during each VIE session. Preliminary results show an overall reduction in PLP and a trend toward improvement in signal-to-motion accuracy over time. These signals allowed MPL users to perform a wide range of hand motions.

  9. Frizzled 3 acts upstream of Alcam during embryonic eye development.

    Science.gov (United States)

    Seigfried, Franziska A; Cizelsky, Wiebke; Pfister, Astrid S; Dietmann, Petra; Walther, Paul; Kühl, Michael; Kühl, Susanne J

    2017-06-01

    Formation of a functional eye during vertebrate embryogenesis requires different processes such as cell differentiation, cell migration, cell-cell interactions as well as intracellular signalling processes. It was previously shown that the non-canonical Wnt receptor Frizzled 3 (Fzd3) is required for proper eye formation, however, the underlying mechanism is poorly understood. Here we demonstrate that loss of Fzd3 induces severe malformations of the developing eye and that this defect is phenocopied by loss of the activated leukocyte cell adhesion molecule (Alcam). Promoter analysis revealed the presence of a Fzd3 responsive element within the alcam promoter, which is responsible for alcam expression during anterior neural development. In-depth analysis identified the jun N-terminal protein kinase 1 (JNK1) and the transcription factor paired box 2 (Pax2) to be important for the activation of alcam expression. Altogether our study reveals that alcam is activated through non-canonical Wnt signalling during embryonic eye development in Xenopus laevis and shows that this pathway plays a similar role in different tissues. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Identification and expression analysis of zebrafish glypicans during embryonic development.

    Directory of Open Access Journals (Sweden)

    Mansi Gupta

    Full Text Available Heparan sulfate Proteoglycans (HSPG are ubiquitous molecules with indispensable functions in various biological processes. Glypicans are a family of HSPG's, characterized by a Gpi-anchor which directs them to the cell surface and/or extracellular matrix where they regulate growth factor signaling during development and disease. We report the identification and expression pattern of glypican genes from zebrafish. The zebrafish genome contains 10 glypican homologs, as opposed to six in mammals, which are highly conserved and are phylogenetically related to the mammalian genes. Some of the fish glypicans like Gpc1a, Gpc3, Gpc4, Gpc6a and Gpc6b show conserved synteny with their mammalian cognate genes. Many glypicans are expressed during the gastrulation stage, but their expression becomes more tissue specific and defined during somitogenesis stages, particularly in the developing central nervous system. Existence of multiple glypican orthologs in fish with diverse expression pattern suggests highly specialized and/or redundant function of these genes during embryonic development.

  11. Live imaging of mitosis in the developing mouse embryonic cortex.

    Science.gov (United States)

    Pilaz, Louis-Jan; Silver, Debra L

    2014-06-04

    Although of short duration, mitosis is a complex and dynamic multi-step process fundamental for development of organs including the brain. In the developing cerebral cortex, abnormal mitosis of neural progenitors can cause defects in brain size and function. Hence, there is a critical need for tools to understand the mechanisms of neural progenitor mitosis. Cortical development in rodents is an outstanding model for studying this process. Neural progenitor mitosis is commonly examined in fixed brain sections. This protocol will describe in detail an approach for live imaging of mitosis in ex vivo embryonic brain slices. We will describe the critical steps for this procedure, which include: brain extraction, brain embedding, vibratome sectioning of brain slices, staining and culturing of slices, and time-lapse imaging. We will then demonstrate and describe in detail how to perform post-acquisition analysis of mitosis. We include representative results from this assay using the vital dye Syto11, transgenic mice (histone H2B-EGFP and centrin-EGFP), and in utero electroporation (mCherry-α-tubulin). We will discuss how this procedure can be best optimized and how it can be modified for study of genetic regulation of mitosis. Live imaging of mitosis in brain slices is a flexible approach to assess the impact of age, anatomy, and genetic perturbation in a controlled environment, and to generate a large amount of data with high temporal and spatial resolution. Hence this protocol will complement existing tools for analysis of neural progenitor mitosis.

  12. Embryonic Stem Cells in Development and Regenerative Medicine.

    Science.gov (United States)

    Doğan, Ayşegül

    2018-02-21

    After progressive improvement in embryonic stem (ES) cell field, several studies have been conducted to explore the usage of ES cells in regenerative medicine. Unlimited self renewal and pluripoteny properties, combined with encouraging preclinical trials, remark that ES cell technology might be promising for clinical practice. ES cells, which can form three germ layers in vitro, are potential candidates to study development at the cellular and molecular level. Understanding the cell fate decision and differentiation processes during development might enable generating functional progenitor cells for tissue restoration. Progression in gene modifications and tissue engineering technology has facilitated the derivation of desired cells for therapy. Success in differentiation protocols and identification the regulatory pathways simplify the research for clinical applications. Although there are established protocols for cell differentiation in vitro and promising preclinical studies in vivo, many challenges need to be adressed before clinical translation. In this review, ES cells are discussed as a model of development in vitro and as a potential candidate for regenerative medicine. This review also dissusses current challenges for ES cell based therapy.

  13. Diverging functions of Scr between embryonic and post-embryonic development in a hemimetabolous insect, Oncopeltus fasciatus.

    Science.gov (United States)

    Chesebro, John; Hrycaj, Steven; Mahfooz, Najmus; Popadić, Aleksandar

    2009-05-01

    Hemimetabolous insects undergo an ancestral mode of development in which embryos hatch into first nymphs that resemble miniature adults. While recent studies have shown that homeotic (hox) genes establish segmental identity of first nymphs during embryogenesis, no information exists on the function of these genes during post-embryogenesis. To determine whether and to what degree hox genes influence the formation of adult morphologies, we performed a functional analysis of Sex combs reduced (Scr) during post-embryonic development in Oncopeltus fasciatus. The main effect was observed in prothorax of Scr-RNAi adults, and ranged from significant alterations in its size and shape to a near complete transformation of its posterior half toward a T2-like identity. Furthermore, while the consecutive application of Scr-RNAi at both of the final two post-embryonic stages (fourth and fifth) did result in formation of ectopic wings on T1, the individual applications at each of these stages did not. These experiments provide two new insights into evolution of wings. First, the role of Scr in wing repression appears to be conserved in both holo- and hemimetabolous insects. Second, the prolonged Scr-depletion (spanning at least two nymphal stages) is both necessary and sufficient to restart wing program. At the same time, other structures that were previously established during embryogenesis are either unaffected (T1 legs) or display only minor changes (labium) in adults. These observations reveal a temporal and spatial divergence of Scr roles during embryonic (main effect in labium) and post-embryonic (main effect in prothorax) development.

  14. Toward Development of Pluripotent Porcine Stem Cells by Road Mapping Early Embryonic Development

    DEFF Research Database (Denmark)

    Petkov, Stoyan; Freude, Kristine; Mashayekhi-Nezamabadi, Kaveh

    2017-01-01

    The lack in production of bona fide porcine pluripotent stem cells has definitely been hampered by a lack of research into porcine embryo development. Embryonic development in mammals is the extraordinary transition of a single-celled fertilized zygote into a complex fetus, which occurs in the ut...

  15. Cytomegalovirus induces abnormal chondrogenesis and osteogenesis during embryonic mandibular development

    Directory of Open Access Journals (Sweden)

    Bringas Pablo

    2008-03-01

    Full Text Available Abstract Background Human clinical studies and mouse models clearly demonstrate that cytomegalovirus (CMV disrupts normal organ and tissue development. Although CMV is one of the most common causes of major birth defects in humans, little is presently known about the mechanism(s underlying CMV-induced congenital malformations. Our prior studies have demonstrated that CMV infection of first branchial arch derivatives (salivary glands and teeth induced severely abnormal phenotypes and that CMV has a particular tropism for neural crest-derived mesenchyme (NCM. Since early embryos are barely susceptible to CMV infection, and the extant evidence suggests that the differentiation program needs to be well underway for embryonic tissues to be susceptible to viral infection and viral-induced pathology, the aim of this study was to determine if first branchial arch NCM cells are susceptible to mCMV infection prior to differentiation of NCM derivatives. Results E11 mouse mandibular processes (MANs were infected with mouse CMV (mCMV for up to 16 days in vitro. mCMV infection of undifferentiated embryonic mouse MANs induced micrognathia consequent to decreased Meckel's cartilage chondrogenesis and mandibular osteogenesis. Specifically, mCMV infection resulted in aberrant stromal cellularity, a smaller, misshapen Meckel's cartilage, and mandibular bone and condylar dysmorphogenesis. Analysis of viral distribution indicates that mCMV primarily infects NCM cells and derivatives. Initial localization studies indicate that mCMV infection changed the cell-specific expression of FN, NF-κB2, RelA, RelB, and Shh and Smad7 proteins. Conclusion Our results indicate that mCMV dysregulation of key signaling pathways in primarily NCM cells and their derivatives severely disrupts mandibular morphogenesis and skeletogenesis. The pathogenesis appears to be centered around the canonical and noncanonical NF-κB pathways, and there is unusual juxtaposition of abnormal stromal

  16. Maternal Embryonic Leucine Zipper Kinase (MELK: A Novel Regulator in Cell Cycle Control, Embryonic Development, and Cancer

    Directory of Open Access Journals (Sweden)

    Pengfei Jiang

    2013-10-01

    Full Text Available Maternal embryonic leucine zipper kinase (MELK functions as a modulator of intracellular signaling and affects various cellular and biological processes, including cell cycle, cell proliferation, apoptosis, spliceosome assembly, gene expression, embryonic development, hematopoiesis, and oncogenesis. In these cellular processes, MELK functions by binding to numerous proteins. In general, the effects of multiple protein interactions with MELK are oncogenic in nature, and the overexpression of MELK in kinds of cancer provides some evidence that it may be involved in tumorigenic process. In this review, our current knowledge of MELK function and recent discoveries in MELK signaling pathway were discussed. The regulation of MELK in cancers and its potential as a therapeutic target were also described.

  17. Role of a novel zebrafish nup98 during embryonic development.

    Science.gov (United States)

    Fung, Tsz-Kan; Chung, Martin I S; Liang, Raymond; Leung, Anskar Y H

    2010-11-01

    The nucleoporin NUP98 is a component of the nuclear pore complex that regulates nucleocytoplasmic trafficking. It has been characterized in acute myeloid leukemia as a fusion partner during chromosomal translocation. In this study, we identified a zebrafish nup98 gene and examined its role in embryonic development. Two expressed sequence tags with translated sequences homologous to human NUP98 were identified. The gene was cloned by polymerase chain reaction from complementary DNA of zebrafish embryos. Cellular functions of zebrafish NUP98 were investigated in HeLa cells. nup98 expression and developmental functions in zebrafish embryos were investigated by whole-mount in situ hybridization and morpholino knockdown. Protein sequence of zebrafish nup98 shared 65% identity with its human homolog. Ectopic expression of zebrafish nup98 rescued the defective messenger RNA export due to human NUP98 knockdown in HeLa cells. In zebrafish embryos, nup98 was expressed diffusely in eyes and the developing brain since 18 hours postfertilization. Knockdown of nup98 with morpholino upregulated pu.1 expression by 39% ± 15% (p = 0.0153) and scl expression by 36% ± 7.6% (p = 0.0017). Expression of genes associated with erythropoiesis was unchanged. The morphants also developed intracranial hemorrhage at 48 hours postfertilization due to defective blood vessel development. A novel zebrafish nup98 was identified and it serves a role in nucleocytoplasmic trafficking similar to human NUP98. During development, it modulates hematopoietic stem cell and early myeloid development and maintains the integrity of cranial vasculature in the developing central nervous system. Copyright © 2010 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

  18. Col11a1 Regulates Bone Microarchitecture during Embryonic Development

    Directory of Open Access Journals (Sweden)

    Anthony Hafez

    2015-12-01

    Full Text Available Collagen XI alpha 1 (Col11a1 is an extracellular matrix molecule required for embryonic development with a role in both nucleating the formation of fibrils and regulating the diameter of heterotypic fibrils during collagen fibrillar assembly. Although found in many different tissues throughout the vertebrate body, Col11a1 plays an essential role in endochondral ossification. To further understand the function of Col11a1 in the process of bone formation, we compared skeletal mineralization in wild-type (WT mice and Col11a1-deficient mice using X-ray microtomography (micro-CT and histology. Changes in trabecular bone microstructure were observed and are presented here. Additionally, changes to the periosteal bone collar of developing long bones were observed and resulted in an increase in thickness in the case of Col11a1-deficient mice compared to WT littermates. Vertebral bodies were incompletely formed in the absence of Col11a1. The data demonstrate that Col11a1 depletion results in alteration to newly-formed bone and is consistent with a role for Col11a1 in mineralization. These findings indicate that expression of Col11a1 in the growth plate and perichondrium is essential for trabecular bone and bone collar formation during endochondral ossification. The observed changes to mineralized tissues further define the function of Col11a1.

  19. Cadmium inhibits neurogenesis in zebrafish embryonic brain development

    International Nuclear Information System (INIS)

    Chow, Elly Suk Hen; Hui, Michelle Nga Yu; Lin Chunchi; Cheng Shukhan

    2008-01-01

    Cadmium is a non-essential heavy metal found abundantly in the environment. Children of women exposed to cadmium during pregnancy display lower motor and perceptual abilities. High cadmium body burden in children is also related to impaired intelligence and lowered school achievement. However, little is known about the molecular and cellular basis of developmental neurotoxicity in the sensitive early life stages of animals. In this study, we explore neurological deficits caused by cadmium during early embryonic stages in zebrafish by examining regionalization of the neural tube, pattern formation and cell fate determination, commitment of proneural genes and induction of neurogenesis. We show that cadmium-treated embryos developed a smaller head with unclear boundaries between the brain subdivisions, particularly in the mid-hindbrain region. Embryos display normal anterior to posterior regionalization; however, the commitment of neural progenitor cells was affected by cadmium. We observe prominent reductions in the expression of several proneuronal genes including ngn1 in cell clusters, zash1a in the developing optic tectum, and zash1b in the telencephalon and tectum. Cadmium-treated embryos also have fewer differentiated neurons and glia in the facial sensory ganglia as indicated by decreased zn-12 expression. Also, a lower transcription level of neurogenic genes, ngn1 and neuroD, is observed in neurons. Our data suggest that cadmium-induced neurotoxicity can be caused by impaired neurogenesis, resulting in markedly reduced neuronal differentiation and axonogenesis

  20. Embryonic development rates of northern grasshoppers (Orthoptera: Acrididae): implications for climate change and habitat management

    Science.gov (United States)

    Temperature-dependent rates of embryonic development are a primary determinant of the life cycle of many species of grasshoppers which, in cold climates, spend two winters in the egg stage. Knowledge of embryonic developmental rates is important for an assessment of the effects of climate change and...

  1. Rac1 modulates cardiomyocyte adhesion during mouse embryonic development

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Issa, Radwan, E-mail: rabuissa@umich.edu

    2015-01-24

    Highlights: • Conditional knockout of Rac1 using Nkx2.5 Cre line is lethal at E13.5. • The myocardium of the mutant is thin and disorganized. • The phenotype is not due to cardiomyocyte low proliferation or apoptosis. • The phenotype is due to specific defect in cardiomyocyte adhesion. - Abstract: Rac1, a member of the Rho subfamily of small GTPases, is involved in morphogenesis and differentiation of many cell types. Here we define a role of Rac1 in cardiac development by specifically deleting Rac1 in the pre-cardiac mesoderm using the Nkx2.5-Cre transgenic driver line. Rac1-conditional knockout embryos initiate heart development normally until embryonic day 11.5 (E11.5); their cardiac mesoderm is specified, and the heart tube is formed and looped. However, by E12.5-E13.5 the mutant hearts start failing and embryos develop edema and hemorrhage which is probably the cause for the lethality observed soon after. The hearts of Rac1-cKO embryos exhibit disorganized and thin myocardial walls and defects in outflow tract alignment. No significant differences of cardiomyocyte death or proliferation were found between developing control and mutant embryos. To uncover the role of Rac1 in the heart, E11.5 primary heart cells were cultured and analyzed in vitro. Rac1-deficient cardiomyocytes were less spread, round and loosely attached to the substrate and to each other implying that Rac1-mediated signaling is required for appropriate cell–cell and/or cellmatrix adhesion during cardiac development.

  2. Rac1 modulates cardiomyocyte adhesion during mouse embryonic development

    International Nuclear Information System (INIS)

    Abu-Issa, Radwan

    2015-01-01

    Highlights: • Conditional knockout of Rac1 using Nkx2.5 Cre line is lethal at E13.5. • The myocardium of the mutant is thin and disorganized. • The phenotype is not due to cardiomyocyte low proliferation or apoptosis. • The phenotype is due to specific defect in cardiomyocyte adhesion. - Abstract: Rac1, a member of the Rho subfamily of small GTPases, is involved in morphogenesis and differentiation of many cell types. Here we define a role of Rac1 in cardiac development by specifically deleting Rac1 in the pre-cardiac mesoderm using the Nkx2.5-Cre transgenic driver line. Rac1-conditional knockout embryos initiate heart development normally until embryonic day 11.5 (E11.5); their cardiac mesoderm is specified, and the heart tube is formed and looped. However, by E12.5-E13.5 the mutant hearts start failing and embryos develop edema and hemorrhage which is probably the cause for the lethality observed soon after. The hearts of Rac1-cKO embryos exhibit disorganized and thin myocardial walls and defects in outflow tract alignment. No significant differences of cardiomyocyte death or proliferation were found between developing control and mutant embryos. To uncover the role of Rac1 in the heart, E11.5 primary heart cells were cultured and analyzed in vitro. Rac1-deficient cardiomyocytes were less spread, round and loosely attached to the substrate and to each other implying that Rac1-mediated signaling is required for appropriate cell–cell and/or cellmatrix adhesion during cardiac development

  3. Visualization of an endogenous retinoic acid gradient across embryonic development.

    Science.gov (United States)

    Shimozono, Satoshi; Iimura, Tadahiro; Kitaguchi, Tetsuya; Higashijima, Shin-Ichi; Miyawaki, Atsushi

    2013-04-18

    In vertebrate development, the body plan is determined by primordial morphogen gradients that suffuse the embryo. Retinoic acid (RA) is an important morphogen involved in patterning the anterior-posterior axis of structures, including the hindbrain and paraxial mesoderm. RA diffuses over long distances, and its activity is spatially restricted by synthesizing and degrading enzymes. However, gradients of endogenous morphogens in live embryos have not been directly observed; indeed, their existence, distribution and requirement for correct patterning remain controversial. Here we report a family of genetically encoded indicators for RA that we have termed GEPRAs (genetically encoded probes for RA). Using the principle of fluorescence resonance energy transfer we engineered the ligand-binding domains of RA receptors to incorporate cyan-emitting and yellow-emitting fluorescent proteins as fluorescence resonance energy transfer donor and acceptor, respectively, for the reliable detection of ambient free RA. We created three GEPRAs with different affinities for RA, enabling the quantitative measurement of physiological RA concentrations. Live imaging of zebrafish embryos at the gastrula and somitogenesis stages revealed a linear concentration gradient of endogenous RA in a two-tailed source-sink arrangement across the embryo. Modelling of the observed linear RA gradient suggests that the rate of RA diffusion exceeds the spatiotemporal dynamics of embryogenesis, resulting in stability to perturbation. Furthermore, we used GEPRAs in combination with genetic and pharmacological perturbations to resolve competing hypotheses on the structure of the RA gradient during hindbrain formation and somitogenesis. Live imaging of endogenous concentration gradients across embryonic development will allow the precise assignment of molecular mechanisms to developmental dynamics and will accelerate the application of approaches based on morphogen gradients to tissue engineering and

  4. Limb ossification in the Paleozoic branchiosaurid Apateon (Temnospondyli) and the early evolution of preaxial dominance in tetrapod limb development.

    Science.gov (United States)

    Fröbisch, Nadia B; Carroll, Robert L; Schoch, Rainer R

    2007-01-01

    Despite the wide range of shapes and sizes that accompany a vast variety of functions, the development of tetrapod limbs follows a conservative pattern of de novo condensation, branching, and segmentation. Development of the zeugopodium and digital arch typically occurs in a posterior to anterior sequence, referred to as postaxial dominance, with a digital sequence of 4-3-5-2-1. The only exception to this pattern in all of living Tetrapoda can be found in salamanders, which display a preaxial dominance in limb development, a de novo condensation of a basale commune (distal carpal/tarsal 1+2) and a precoccial development of digits I and II. These divergent patterns have puzzled researchers for over a century leading to various explanatory hypotheses. Despite many advances in research on tetrapod limb development, the divergent evolution of these two pathways and its causes are still not understood. Based on an extensive ontogenetic series we investigated the pattern of limb development of the 300 Ma old branchiosaurid amphibian Apateon. This revealed a preaxial dominance in limb development that was previously believed to be unique and derived for modern salamanders. The Branchiosauridae are favored as close relatives of extant salamanders in most phylogenetic hypotheses of the highly controversial origins and relationships of extant amphibians. The findings provide new insights into the evolution of developmental pathways in tetrapod limb development, the relationships of modern amphibians with possible Paleozoic antecedents, and their initial timing of divergence.

  5. High-throughput identification of small molecules that affect human embryonic vascular development

    Science.gov (United States)

    Vazão, Helena; Rosa, Susana; Barata, Tânia; Costa, Ricardo; Pitrez, Patrícia R.; Honório, Inês; de Vries, Margreet R.; Papatsenko, Dimitri; Benedito, Rui; Saris, Daniel; Khademhosseini, Ali; Quax, Paul H. A.; Pereira, Carlos F.; Mercader, Nadia; Ferreira, Lino

    2017-01-01

    Birth defects, which are in part caused by exposure to environmental chemicals and pharmaceutical drugs, affect 1 in every 33 babies born in the United States each year. The current standard to screen drugs that affect embryonic development is based on prenatal animal testing; however, this approach yields low-throughput and limited mechanistic information regarding the biological pathways and potential adverse consequences in humans. To develop a screening platform for molecules that affect human embryonic development based on endothelial cells (ECs) derived from human pluripotent stem cells, we differentiated human pluripotent stem cells into embryonic ECs and induced their maturation under arterial flow conditions. These cells were then used to screen compounds that specifically affect embryonic vasculature. Using this platform, we have identified two compounds that have higher inhibitory effect in embryonic than postnatal ECs. One of them was fluphenazine (an antipsychotic), which inhibits calmodulin kinase II. The other compound was pyrrolopyrimidine (an antiinflammatory agent), which inhibits vascular endothelial growth factor receptor 2 (VEGFR2), decreases EC viability, induces an inflammatory response, and disrupts preformed vascular networks. The vascular effect of the pyrrolopyrimidine was further validated in prenatal vs. adult mouse ECs and in embryonic and adult zebrafish. We developed a platform based on human pluripotent stem cell-derived ECs for drug screening, which may open new avenues of research for the study and modulation of embryonic vasculature. PMID:28348206

  6. Embryonic muscle development of Convoluta pulchra (Turbellaria-acoelomorpha, platyhelminthes).

    Science.gov (United States)

    Ladurner, P; Rieger, R

    2000-06-15

    We studied the embryonic development of body-wall musculature in the acoel turbellarian Convoluta pulchra by fluorescence microscopy using phalloidin-bound stains for F-actin. During stage 1, which we define as development prior to 50% of the time between egg-laying and hatching, actin was visible only in zonulae adhaerentes of epidermal cells. Subsequent development of muscle occurred in two distinct phases: first, formation of an orthogonal grid of early muscles and, second, differentiation of other myoblasts upon this grid. The first elements of the primary orthogonal muscle grid appeared as short, isolated, circular muscle fibers (stage 2; 50% developmental time), which eventually elongated to completely encircle the embryo (stage 3; at 60% of total developmental time). The first primary longitudinal fibers appeared later, along with some new primary circular fibers, by 60-63% of total developmental time (stage 4). From 65 to 100% of total developmental time (stages 5 to 7), secondary fibers, using primary fibers as templates, arose; the number of circular and longitudinal muscles thus increased, and at the same time parenchymal muscles began appearing. Hatchlings (stage 8) possessed about 25 circular and 30 longitudinal muscles as well as strong parenchymal muscles. The remarkable feature of the body wall of many adult acoel flatworms is that longitudinal muscles bend medially and cross each other behind the level of the mouth. We found that this development starts shortly after the appearance of the ventral mouth opening within the body wall muscle grid. The adult organization of the body-wall musculature consists of a grid of several hundred longitudinal and circular fibers and a few diagonal muscles. Musculature of the reproductive organs developed after hatching. Thus, extensive myogenesis must occur also during postembryonic development. Comparison between the turbellarians and the annelids suggests that formation of a primary orthogonal muscle grid and

  7. Embryonic development of endoderm in chicken (Gallus gallus domesticus).

    Science.gov (United States)

    Alcântara, Dayane; Rodrigues, Marcio N; Franciolli, André L R; Da Fonseca, Erika T; Silva, Fernanda M O; Carvalho, Rafael C; Fratini, Paula; Sarmento, Carlos Alberto P; Ferreira, Antonio José P; Miglino, Maria Angelica

    2013-08-01

    The poultry industry is a sector of agribusiness which represents an important role in the country's agricultural exports. Therefore, the study about embryogenesis of the domestic chicken (Gallus gallus domesticus) has a great economic importance. The aim of this study was to evaluate embryonic development of the endoderm in chicken (Gallus gallus domesticus). Forty fertilized eggs of domestic chickens, starting from the 1st day of gestation and so on until the 19 days of the incubation were collected from the Granja São José (Amparo, SP, Brazil). Embryos and fetus were fixed in 10% formaldehyde solution, identified, weighed, measured, and subjected to light and scanning electron microscopy. The endoderm originates the internal lining epithelium of the digestive, immune, respiratory systems, and the organs can be visualized from the second day (48 h) when the liver is formed. The formation of the digestive system was complete in the 12th day. Respiratory system organs begin at the fourth day as a disorganized tissue and undifferentiated. Their complete differentiation was observed at the 10 days of incubation, however, until the 19 days the syrinx was not observed. The formation of immune system at 10th day was observed with observation of the spleen, thymus, and cloacal bursa. The study of the organogenesis of the chicken based on germ layers is very complex and underexplored, and the study of chicken embryology is very important due the economic importance and growth of the use of this animal model studies such as genetic studies. Copyright © 2013 Wiley Periodicals, Inc.

  8. Innovative virtual reality measurements for embryonic growth and development

    NARCIS (Netherlands)

    C.M. Verwoerd-Dikkeboom (Christine); A.H.J. Koning (Anton); W.C.J. Hop (Wim); P.J. van der Spek (Peter); N. Exalto (Niek); R.P.M. Steegers-Theunissen (Régine)

    2010-01-01

    textabstractBackground Innovative imaging techniques, using up-to-date ultrasonic equipment, necessitate specific biometry. The aim of our study was to test the possibility of detailed human embryonic biometry using a virtual reality (VR) technique. Methods In a longitudinal study, three-dimensional

  9. Cell surface carbohydrate changes during embryonic and fetal skin development

    DEFF Research Database (Denmark)

    Dabelsteen, Erik; Holbrook, K; Clausen, H

    1986-01-01

    Monoclonal antibodies to four type 2 chain carbohydrate antigens were used for immunohistochemical studies of embryonic and fetal skin. The antibodies detected N-acetyllactosamine and 3 fucosyl substitutes of this, blood group antigen H, Lex, and Ley. Periderm consistently stained for N-acetyllac...

  10. Abnormal placental development and early embryonic lethality in EpCAM-null mice.

    Science.gov (United States)

    Nagao, Keisuke; Zhu, Jianjian; Heneghan, Mallorie B; Hanson, Jeffrey C; Morasso, Maria I; Tessarollo, Lino; Mackem, Susan; Udey, Mark C

    2009-12-31

    EpCAM (CD326) is encoded by the tacstd1 gene and expressed by a variety of normal and malignant epithelial cells and some leukocytes. Results of previous in vitro experiments suggested that EpCAM is an intercellular adhesion molecule. EpCAM has been extensively studied as a potential tumor marker and immunotherapy target, and more recent studies suggest that EpCAM expression may be characteristic of cancer stem cells. To gain insights into EpCAM function in vivo, we generated EpCAM -/- mice utilizing an embryonic stem cell line with a tacstd1 allele that had been disrupted. Gene trapping resulted in a protein comprised of the N-terminus of EpCAM encoded by 2 exons of the tacstd1 gene fused in frame to betageo. EpCAM +/- mice were viable and fertile and exhibited no obvious abnormalities. Examination of EpCAM +/- embryos revealed that betageo was expressed in several epithelial structures including developing ears (otocysts), eyes, branchial arches, gut, apical ectodermal ridges, lungs, pancreas, hair follicles and others. All EpCAM -/- mice died in utero by E12.5, and were small, developmentally delayed, and displayed prominent placental abnormalities. In developing placentas, EpCAM was expressed throughout the labyrinthine layer and by spongiotrophoblasts as well. Placentas of EpCAM -/- embryos were compact, with thin labyrinthine layers lacking prominent vascularity. Parietal trophoblast giant cells were also dramatically reduced in EpCAM -/- placentas. EpCAM was required for differentiation or survival of parietal trophoblast giant cells, normal development of the placental labyrinth and establishment of a competent maternal-fetal circulation. The findings in EpCAM-reporter mice suggest involvement of this molecule in development of vital organs including the gut, kidneys, pancreas, lungs, eyes, and limbs.

  11. Type 1 and 3 inositol trisphosphate receptors are required for extra-embryonic vascular development.

    Science.gov (United States)

    Uchida, Keiko; Nakazawa, Maki; Yamagishi, Chihiro; Mikoshiba, Katsuhiko; Yamagishi, Hiroyuki

    2016-10-01

    The embryonic-maternal interface of the placental labyrinth, allantois, and yolk sac are vital during embryogenesis; however, the precise mechanism underlying the vascularization of these structures remains unknown. Herein we focus on the role of inositol 1,4,5-trisphosphate (IP3) receptors (IP3R), which are intracellular Ca(2+) release channels, in placentation. Double knockout (DKO) of type 1 and 3 IP3Rs (IP3R1 and IP3R3, respectively) in mice resulted in embryonic lethality around embryonic day (E) 11.5. Because IP3R1 and IP3R3 were co-expressed in endothelial cells in the labyrinth, allantois, and yolk sac, we investigated extra-embryonic vascular development in IP3R1- and IP3R3-DKO mice. The formation of chorionic plates and yolk sac vessels seemed dysregulated around the timing of the chorio-allantoic attachment, immediately followed by the disorganization of allantoic vessels, the decreased expression of the spongiotrophoblast cell marker Tpbpa and the growth retardation of the embryos in DKO mice. Fluorescent immunohistochemistry demonstrated downregulation of a vascular endothelial marker, CD31, in labyrinth embryonic vessels and poor elongation of extra-embryonic mesoderm into the labyrinth layer in DKO placenta, whereas the branching of the DKO chorionic trophoblast was initiated. In addition, allantoic and yolk sac vessels in extra-embryonic tissues were less remodeled in DKO mice. In vitro endothelial cord formation and migration activities of cultured vascular endothelial cells derived from human umbilical vein were downregulated under the inhibition of IP3R. Our results suggest that IP3R1 and IP3R3 are required for extra-embryonic vascularization in the placenta, allantois, and yolk sac. This is the first demonstration of the essential role of IP3/IP3Rs signaling in the development of the vasculature at the embryonic-maternal interface. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Biphasic influence of dexamethasone exposure on embryonic vertebrate skeleton development

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Xin; Chen, Jian-long; Ma, Zheng-lai; Zhang, Zhao-long; Lv, Shun; Mai, Dong-mei; Liu, Jia-jia [Department of Histology and Embryology, Key Laboratory for Regenerative Medicine of the Ministry of Education, School of Medicine, Jinan University, Guangzhou 510632 (China); Chuai, Manli [Division of Cell and Developmental Biology, University of Dundee, Dundee DD1 5EH (United Kingdom); Lee, Kenneth Ka Ho; Wan, Chao [Stem Cell and Regeneration Thematic Research Programme, School of Biomedical Sciences, Chinese University of Hong Kong, Shatin (Hong Kong); Yang, Xuesong, E-mail: yang_xuesong@126.com [Department of Histology and Embryology, Key Laboratory for Regenerative Medicine of the Ministry of Education, School of Medicine, Jinan University, Guangzhou 510632 (China); Institute of Fetal-Preterm Labor Medicine, Jinan University, Guangzhou 510632 (China)

    2014-11-15

    Dexamethasone (Dex) has anti-inflammatory and immunomodulatory properties against many conditions. There is a potential teratogenic risk, however, for pregnant women receiving Dex treatment. It has been claimed that Dex exposure during pregnancy could affect osteogenesis in the developing embryo, which still remains highly controversial. In this study, we employed chick embryos to investigate the effects of Dex exposure on skeletal development using combined in vivo and in vitro approach. First, we demonstrated that Dex (10{sup −8}–10{sup −6} μmol/egg) exposure resulted in a shortening of the developing long bones of chick embryos, and it accelerated the deposition of calcium salts. Secondly, histological analysis of chick embryo phalanxes exhibited Dex exposure inhibited the proliferation of chondrocytes, increased apoptosis of chondrocytes and osteocytes, and led to atypical arranged hypertrophic chondrocytes. The expression of genes related to skeletogenesis was also analyzed by semi-quantitative RT-PCR. The expression of ALP, Col1a2 and Col2a1 was decreased in the Dex treated phalanxes. A detectable increase was observed in Runx-2 and Mmp-13 expression. We next examined how Dex affected the different stages of skeletogenesis in vitro. Utilizing limb bud mesenchyme micromass cultures, we determined that Dex exposure exerted no effect on apoptosis but impaired chondrogenic cell proliferation. Interestingly, low dose of Dex moderately prompted nodule formation as revealed by alcian blue staining, but higher doses of Dex significantly inhibited similar chondrogenic differentiation. Dex exposure did not induce apoptosis when the chondrogenic precursors were still at the mesenchymal stage, however, cell viability was suppressed when the mesenchyme differentiated into chondrocytes. Alizarin red staining revealed that the capacity to form mineralized bone nodules was correspondingly enhanced as Dex concentrations increased. The mRNA level of Sox-9 was slightly

  13. Biphasic influence of dexamethasone exposure on embryonic vertebrate skeleton development

    International Nuclear Information System (INIS)

    Cheng, Xin; Chen, Jian-long; Ma, Zheng-lai; Zhang, Zhao-long; Lv, Shun; Mai, Dong-mei; Liu, Jia-jia; Chuai, Manli; Lee, Kenneth Ka Ho; Wan, Chao; Yang, Xuesong

    2014-01-01

    Dexamethasone (Dex) has anti-inflammatory and immunomodulatory properties against many conditions. There is a potential teratogenic risk, however, for pregnant women receiving Dex treatment. It has been claimed that Dex exposure during pregnancy could affect osteogenesis in the developing embryo, which still remains highly controversial. In this study, we employed chick embryos to investigate the effects of Dex exposure on skeletal development using combined in vivo and in vitro approach. First, we demonstrated that Dex (10 −8 –10 −6 μmol/egg) exposure resulted in a shortening of the developing long bones of chick embryos, and it accelerated the deposition of calcium salts. Secondly, histological analysis of chick embryo phalanxes exhibited Dex exposure inhibited the proliferation of chondrocytes, increased apoptosis of chondrocytes and osteocytes, and led to atypical arranged hypertrophic chondrocytes. The expression of genes related to skeletogenesis was also analyzed by semi-quantitative RT-PCR. The expression of ALP, Col1a2 and Col2a1 was decreased in the Dex treated phalanxes. A detectable increase was observed in Runx-2 and Mmp-13 expression. We next examined how Dex affected the different stages of skeletogenesis in vitro. Utilizing limb bud mesenchyme micromass cultures, we determined that Dex exposure exerted no effect on apoptosis but impaired chondrogenic cell proliferation. Interestingly, low dose of Dex moderately prompted nodule formation as revealed by alcian blue staining, but higher doses of Dex significantly inhibited similar chondrogenic differentiation. Dex exposure did not induce apoptosis when the chondrogenic precursors were still at the mesenchymal stage, however, cell viability was suppressed when the mesenchyme differentiated into chondrocytes. Alizarin red staining revealed that the capacity to form mineralized bone nodules was correspondingly enhanced as Dex concentrations increased. The mRNA level of Sox-9 was slightly increased

  14. GLUT3 gene expression is critical for embryonic growth, brain development and survival.

    Science.gov (United States)

    Carayannopoulos, Mary O; Xiong, Fuxia; Jensen, Penny; Rios-Galdamez, Yesenia; Huang, Haigen; Lin, Shuo; Devaskar, Sherin U

    2014-04-01

    Glucose is the primary energy source for eukaryotic cells and the predominant substrate for the brain. GLUT3 is essential for trans-placental glucose transport and highly expressed in the mammalian brain. To further elucidate the role of GLUT3 in embryonic development, we utilized the vertebrate whole animal model system of Danio rerio as a tractable system for defining the cellular and molecular mechanisms altered by impaired glucose transport and metabolism related to perturbed expression of GLUT3. The comparable orthologue of human GLUT3 was identified and the expression of this gene abrogated during early embryonic development. In a dose-dependent manner embryonic brain development was disrupted resulting in a phenotype of aberrant brain organogenesis, associated with embryonic growth restriction and increased cellular apoptosis. Rescue of the morphant phenotype was achieved by providing exogenous GLUT3 mRNA. We conclude that GLUT3 is critically important for brain organogenesis and embryonic growth. Disruption of GLUT3 is responsible for the phenotypic spectrum of embryonic growth restriction to demise and neural apoptosis with microcephaly. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Actin cytoskeleton contributes to the elastic modulus of embryonic tendon during early development.

    Science.gov (United States)

    Schiele, Nathan R; von Flotow, Friedrich; Tochka, Zachary L; Hockaday, Laura A; Marturano, Joseph E; Thibodeau, Jeffrey J; Kuo, Catherine K

    2015-06-01

    Tendon injuries are common and heal poorly. Strategies to regenerate or replace injured tendons are challenged by an incomplete understanding of normal tendon development. Our previous study showed that embryonic tendon elastic modulus increases as a function of developmental stage. Inhibition of enzymatic collagen crosslink formation abrogated increases in tendon elastic modulus at late developmental stages, but did not affect increases in elastic modulus of early stage embryonic tendons. Here, we aimed to identify potential contributors to the mechanical properties of these early stage embryonic tendons. We characterized tendon progenitor cells in early stage embryonic tendons, and the influence of actin cytoskeleton disruption on tissue elastic modulus. Cells were closely packed in embryonic tendons, and did not change in density during early development. We observed an organized network of actin filaments that seemed contiguous between adjacent cells. The actin filaments exhibited a crimp pattern with a period and amplitude that matched the crimp of collagen fibers at each developmental stage. Chemical disruption of the actin cytoskeleton decreased tendon tissue elastic modulus, measured by atomic force microscopy. Our results demonstrate that early developmental stage embryonic tendons possess a well organized actin cytoskeleton network that contributes significantly to tendon tissue mechanical properties. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  16. Intraspecific Variation in and Environment-Dependent Resource Allocation to Embryonic Development Time in Common Terns.

    Science.gov (United States)

    Vedder, Oscar; Kürten, Nathalie; Bouwhuis, Sandra

    Embryonic development time is thought to impact life histories through trade-offs against life-history traits later in life, yet the inference is based on interspecific comparative analyses only. It is largely unclear whether intraspecific variation in embryonic development time that is not caused by environmental differences occurs, which would be required to detect life-history trade-offs. Here we performed a classical common-garden experiment by incubating fresh eggs of free-living common terns (Sterna hirundo) in a controlled incubation environment at two different temperatures. Hatching success was high but was slightly lower at the lower temperature. While correcting for effects of year, incubation temperature, and laying order, we found significant variation in the incubation time embryos required until hatching and in their heart rate. Embryonic heart rate was significantly positively correlated within clutches, and a similar tendency was found for incubation time, suggesting that intrinsic differences in embryonic development rate between offspring of different parents exist. Incubation time and embryonic heart rate were strongly correlated: embryos with faster heart rates required shorter incubation time. However, after correction for heart rate, embryos still required more time for development at the lower incubation temperature. This suggests that processes other than development require a greater share of resources in a suboptimal environment and that relative resource allocation to development is, therefore, environment dependent. We conclude that there is opportunity to detect intraspecific life-history trade-offs with embryonic development time and that the resolution of trade-offs may differ between embryonic environments.

  17. Cell surface carbohydrate changes during embryonic and fetal skin development

    DEFF Research Database (Denmark)

    Dabelsteen, Erik; Holbrook, K; Clausen, H

    1986-01-01

    Monoclonal antibodies to four type 2 chain carbohydrate antigens were used for immunohistochemical studies of embryonic and fetal skin. The antibodies detected N-acetyllactosamine and 3 fucosyl substitutes of this, blood group antigen H, Lex, and Ley. Periderm consistently stained for N-acetyllac......Monoclonal antibodies to four type 2 chain carbohydrate antigens were used for immunohistochemical studies of embryonic and fetal skin. The antibodies detected N-acetyllactosamine and 3 fucosyl substitutes of this, blood group antigen H, Lex, and Ley. Periderm consistently stained for N......-acetyllactosamine, Lex and Ley. The H antigen showed a variable and weak expression on peridermal cells from day 57 to day 84 estimated gestation age (EGA). After this period the H antigen was no longer expressed at peridermal cells. In the epidermis, N-acetyllactosamine was present on all cells until the age of 15...... weeks EGA. After this period N-acetyllactosamine could only be demonstrated on basal cells after treatment with neuraminidase, indicating a masking of N-acetyllactosamine by sialic acid. The H antigen could not be demonstrated in the epithelium before 14 weeks EGA. At this time it appeared on spinous...

  18. Evolution and development of mammalian limb integumentary structures.

    Science.gov (United States)

    Hamrick, Mark W

    2003-08-15

    The adaptive radiation of mammalian clades has involved marked changes in limb morphology that have affected not only the skeleton but also the integumentary structures. For example, didelphid marsupials show distinct differences in nail and claw morphology that are functionally related to the evolution of arboreal, terrestrial, and aquatic foraging behaviors. Vespertilionoid bats have evolved different volar pad structures such as adhesive discs, scales, and skin folds, whereas didelphid marsupials have apical pads covered either with scales, ridges, or small cones. Comparative analysis of pad and claw development reveals subtle differences in mesenchymal and ectodermal patterning underlying interspecific variation in morphology. Analysis of gene expression during pad and claw development reveals that signaling molecules such as Msx1 and Hoxc13 play important roles in the morphogenesis of these integumentary structures. These findings suggest that evolutionary change in the expression of these molecules, and in the response of mesenchymal and ectodermal cells to these signaling factors, may underlie interspecific differences in nail, claw, and volar pad morphology. Evidence from comparative morphology, development, and functional genomics therefore sheds new light on both the patterns and mechanisms of evolutionary change in mammalian limb integumentary structures. Copyright 2003 Wiley-Liss, Inc.

  19. Microanatomical Study of Embryonic Gonadal Development in Japanese Quail (Coturnix japonica

    Directory of Open Access Journals (Sweden)

    Sittipon Intarapat

    2014-01-01

    Full Text Available Gonadal development of quail embryos was examined histologically using histological and histochemical methods. In the present study, quail embryos were studied at various stages of incubation period based on phases of gonadogenesis. Germ cell migration was observed on day 3-4 but gonadal differentiation and gonadal function were observed on day 6–8 and day 11–14, respectively. During germ cell migration, quail primordial germ cells (qPGCs were successfully detected in both left and right genital ridges as well as the dorsal mesentery by lectin histochemistry. Unexpectedly, qPGCs-like cells were found next to the neural tube by Mallory-AZAN stain. During gonadal differentiation, embryonic sex can be distinguished histologically since day 8 of incubation. Embryonic testis exhibited a thin cortex, whereas embryonic ovary exhibited a thick cortex. Testicular cord formation was found in the medulla of embryonic testes while the lacunae and fat-laden cells were found in the medulla of embryonic ovary during gonadal function. This is the first report on a comparison of phases of gonadogenesis and histochemical study of quail embryonic gonads in both sexes.

  20. Abnormal coronary tree development in embryonic hypoxia leads to heart failure and embryonic lethality.

    Czech Academy of Sciences Publication Activity Database

    Naňka, O.; Sedmera, David; Grim, M.

    2007-01-01

    Roč. 21, č. 6 (2007), s. 778.8 ISSN 0892-6638. [Experimental Biology 2007. 27.04.2007-03.05.2007, Washington DC] Institutional research plan: CEZ:AV0Z50450515 Keywords : coronary tree development Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  1. Effect of temperature on embryonic development of Melanotaenia boesemani (Allen and Cross, 1982).

    Science.gov (United States)

    Radael, Marcella Costa; Cardoso, Leonardo Demier; de Andrade, Dalcio Ricardo; Ferreira, André Veloso; da Cruz Mattos, Douglas; Vidal, Manuel Vazquez

    2016-04-01

    The present study aimed to provide data on the time required for Melanotaenia boesemani to complete embryonic development, and to investigate the influence that incubation at different temperatures caused in this species. The effects of temperature on the time and hatching rate are presented, as well as information related to embryonic development stages. After fertilization, the eggs were kept in incubators at 23, 26, 29 or 32°C and observed at predetermined times until the moment of hatching. Stages of development were identified and classified according to morphological and physiological characteristics. Oil droplets were visualized inside the eggs as well as filament adhesion present at the chorion. Embryonic development was similar to that observed in other species of the genus Melanotaenia with hatching and faster development in higher temperatures.

  2. Microfluidic-based patterning of embryonic stem cells for in vitro development studies.

    Science.gov (United States)

    Suri, Shalu; Singh, Ankur; Nguyen, Anh H; Bratt-Leal, Andres M; McDevitt, Todd C; Lu, Hang

    2013-12-07

    In vitro recapitulation of mammalian embryogenesis and examination of the emerging behaviours of embryonic structures require both the means to engineer complexity and accurately assess phenotypes of multicellular aggregates. Current approaches to study multicellular populations in 3D configurations are limited by the inability to create complex (i.e. spatially heterogeneous) environments in a reproducible manner with high fidelity thus impeding the ability to engineer microenvironments and combinations of cells with similar complexity to that found during morphogenic processes such as development, remodelling and wound healing. Here, we develop a multicellular embryoid body (EB) fusion technique as a higher-throughput in vitro tool, compared to a manual assembly, to generate developmentally relevant embryonic patterns. We describe the physical principles of the EB fusion microfluidic device design; we demonstrate that >60 conjoined EBs can be generated overnight and emulate a development process analogous to mouse gastrulation during early embryogenesis. Using temporal delivery of bone morphogenic protein 4 (BMP4) to embryoid bodies, we recapitulate embryonic day 6.5 (E6.5) during mouse embryo development with induced mesoderm differentiation in murine embryonic stem cells leading to expression of Brachyury-T-green fluorescent protein (T-GFP), an indicator of primitive streak development and mesoderm differentiation during gastrulation. The proposed microfluidic approach could be used to manipulate hundreds or more of individual embryonic cell aggregates in a rapid fashion, thereby allowing controlled differentiation patterns in fused multicellular assemblies to generate complex yet spatially controlled microenvironments.

  3. Hepatic lipogenesis in broiler chickens with different fat deposition during embryonic development.

    Science.gov (United States)

    Zhao, S; Ma, H; Zou, S; Chen, W; Zhao, R

    2007-02-01

    In order to identify the genes involved in the fatness variability, we studied the expression of several genes implicated in the hepatic lipid metabolism of broiler chickens with different fat deposition patterns during embryonic development. The mRNA expression of acetyl CoA carboxylase (ACC), fatty acid synthase (FAS), malic enzyme (ME) and apolipoprotein B100 (apoB100) genes were determined using reverse transcriptase-polymerase chain reaction (RT-PCR). Samples of livers were collected from Arbor Acres (AA) and Sanhuang (SH) chickens on day 9, 14 and 19 of embryonic development as well as at hatching. This study showed that hepatic triglyceride (TG) level was found to increase suddenly during day 14 of embryonic development, to gradually increase thereafter, and to remain relatively constant at hatching. FAS gene expression in AA and SH broilers occurred prior to hatching and at hatching. The gene was expressed more in the former breed. ACC gene expression was observed beginning at the earlier development stage of days 9. No breed difference was observed in ME and apoB gene expression. This study indicated that the expression of lipogenic enzyme genes of the liver in broiler chickens exhibited scheduling during embryogenesis. The ACC gene started to express earlier than the FAS gene during embryonic development. This suggested that embryonic liver synthesized fatty acid, and breed difference was noticed prior to hatching.

  4. Low oxygen levels slow embryonic development of Limulus polyphemus

    DEFF Research Database (Denmark)

    Funch, Peter; Wang, Tobias; Pertoldi, Cino

    2016-01-01

    The American horseshoe crab Limulus polyphemus typically spawns in the upper intertidal zone, where the developing embryos are exposed to large variations in abiotic factors such as temperature, humidity, salinity, and oxygen, which affect the rate of development. It has been shown that embryonic...... development is slowed at both high and low salinities and temperatures, and that late embryos close to hatching tolerate periodic hypoxia. In this study we investigated the influence of hypoxia on both early and late embryonic development in L. polyphemus under controlled laboratory conditions. Embryos were...

  5. Arrested embryonic development: a review of strategies to delay hatching in egg-laying reptiles

    Science.gov (United States)

    Rafferty, Anthony R.; Reina, Richard D.

    2012-01-01

    Arrested embryonic development involves the downregulation or cessation of active cell division and metabolic activity, and the capability of an animal to arrest embryonic development results in temporal plasticity of the duration of embryonic period. Arrested embryonic development is an important reproductive strategy for egg-laying animals that provide no parental care after oviposition. In this review, we discuss each type of embryonic developmental arrest used by oviparous reptiles. Environmental pressures that might have directed the evolution of arrest are addressed and we present previously undiscussed environmentally dependent physiological processes that may occur in the egg to bring about arrest. Areas for future research are proposed to clarify how ecology affects the phenotype of developing embryos. We hypothesize that oviparous reptilian mothers are capable of providing their embryos with a level of phenotypic adaptation to local environmental conditions by incorporating maternal factors into the internal environment of the egg that result in different levels of developmental sensitivity to environmental conditions after they are laid. PMID:22438503

  6. Ultrastructure of the intrauterine eggs of the microphallid trematode Maritrema feliui: evidence of early embryonic development.

    Science.gov (United States)

    Swiderski, Zdzisław; Miquel, Jordi; Montoliu, Isabel; Feliu, Carlos; Gibson, David I

    2013-09-01

    Intrauterine embryonic development in the microphallid trematode Maritrema feliui is examined by means of transmission electron microscopy. Both fertilization and eggshell formation take place in the ootype. The eggshell is formed from a shell globule material derived from the vitelline cells combined with secretions of Mehlis' gland. The proximal uterus is packed with unembryonated eggs of the oligolecithal type, each composed of a fertilized oocyte and several vitelline cells, all surrounded by the shell. Intrauterine embryonic development of the egg is followed to the early stage of outer embryonic envelope formation, resulting in an embryo of ~20 blastomeres of three different types: macromeres, mesomeres and micromeres. The first equal cleavage division of the zygote produces two macromeres. The outer envelope is of cellular origin and formed by the cytoplasmic fusion of two macromeres, which become situated at opposite poles in the peripheral layer of the embryo just beneath the eggshell. Simultaneously, other blastomeres multiply and differentiate, whereas several micromeres exhibit clear signs of degeneration or apoptosis. These results show that the embryonic development of M. feliui starts in utero and represents an example of early stage ovoviviparity. A reduction in the number of blastomeres results from a continued degeneration of micromeres, which after autolysis and re-absorption, appear to represent an important source of nutritive reserves for the embryo. The embryonic development of this digenean is discussed in relation to its life cycle.

  7. The Diverse Role of Ldb1 in Cell Differentiation and Mouse Embryonic Development

    NARCIS (Netherlands)

    M-A. Mylona (Maria-Anthina)

    2009-01-01

    textabstractDuring the development of the mouse embryo tightly regulated differentiation pathways lead to the formation of the tissues and organs of the adult animal. The role of Ldb1 during embryonic development and in particular during hematopoiesis and neural development will be the focus of this

  8. [Variants of anatomical structure of lower-limb veins as a possible cause of the development of primary varicosity].

    Science.gov (United States)

    Vakhitov, M Kh; Bol'shakov, O P

    2011-01-01

    In order to reveal anatomical prerequisites for the development of primary varicose veins we investigated the structure of the venous system on a total of 53 adult human cadaveric lower extremities. Congenital morphological grounds providing the phlebohaemodynemics of the lower limbs are ambiguous in different individual forms. We revealed a total of 18 variants of the structure of deep veins, reflecting various stages of the embryonic development. In 34.1% of cases we saw the forms characteristic of incomplete reduction and unfinished transformation, with 30.2% of cases showing the utmost degree of reduction and transformation. An inadequate outflow along the deep veins conditioned by their anatomical structure is a prerequisite for the development of valvular insufficiency and venous reflux to the superficial veins followed by varicose transformation thereof

  9. Embryonic development of nudibranch species (Mollusca: Opisthobranchia in the Gulf of Thailand

    Directory of Open Access Journals (Sweden)

    Pattira Kasamesiri

    2014-12-01

    Full Text Available Objective: To find the possible way to predict the mode of embryonic development of nudibranchs, focusing on egg mass characteristics, embryonic development, and shell patterns of the veligers. Methods: Eight species of nudibranch were collected in the eastern part of the Gulf of Thailand. The specimens were allowed to copulate and lay their egg masses under laboratory conditions. Embryonic development was monitored under a light microscope with a digital camera every day until hatching. Results: Most of the species of nudibranch collected had a single larva in each egg capsule that developed, except for Jorunna funebris, which had 1-4 larvae in each egg capsule. All the specimens had the same pattern of cell division and hatching into the water column during the veliger form. However, the species developed at different rates in each stage. Conclusions: All species in the current study had planktotrophic development except Doriprismatica atromarginata, which showed lecithotrophic development. Based on embryonic development among the nudibranchs that showed planktotrophic development, Jorunna funebris appeared to be the most advantageous species for culture development with regard to utilization and conservation in the future.

  10. The ‘Ventral Organs’ of Pycnogonida (Arthropoda) Are Neurogenic Niches of Late Embryonic and Post-Embryonic Nervous System Development

    Science.gov (United States)

    Brenneis, Georg; Scholtz, Gerhard

    2014-01-01

    Early neurogenesis in arthropods has been in the focus of numerous studies, its cellular basis, spatio-temporal dynamics and underlying genetic network being by now comparably well characterized for representatives of chelicerates, myriapods, hexapods and crustaceans. By contrast, neurogenesis during late embryonic and/or post-embryonic development has received less attention, especially in myriapods and chelicerates. Here, we apply (i) immunolabeling, (ii) histology and (iii) scanning electron microscopy to study post-embryonic ventral nerve cord development in Pseudopallene sp., a representative of the sea spiders (Pycnogonida), the presumable sister group of the remaining chelicerates. During early post-embryonic development, large neural stem cells give rise to additional ganglion cell material in segmentally paired invaginations in the ventral ectoderm. These ectodermal cell regions – traditionally designated as ‘ventral organs’ – detach from the surface into the interior and persist as apical cell clusters on the ventral ganglion side. Each cluster is a post-embryonic neurogenic niche that features a tiny central cavity and initially still houses larger neural stem cells. The cluster stays connected to the underlying ganglionic somata cortex via an anterior and a posterior cell stream. Cell proliferation remains restricted to the cluster and streams, and migration of newly produced cells along the streams seems to account for increasing ganglion cell numbers in the cortex. The pycnogonid cluster-stream-systems show striking similarities to the life-long neurogenic system of decapod crustaceans, and due to their close vicinity to glomerulus-like neuropils, we consider their possible involvement in post-embryonic (perhaps even adult) replenishment of olfactory neurons – as in decapods. An instance of a potentially similar post-embryonic/adult neurogenic system in the arthropod outgroup Onychophora is discussed. Additionally, we document two transient

  11. Vitamin B-complex initiates growth and development of human embryonic brain cells in vitro.

    Science.gov (United States)

    Danielyan, K E; Abramyan, R A; Galoyan, A A; Kevorkian, G A

    2011-09-01

    We studied a combined effect of subcomponents of vitamin B complex on the growth, development, and death of human embryonic brain-derived cells (E90) cultured using a modified method of Matson. Cell death was detected by trypan blue staining. According to our results, vitamin B-complex in low-doses promote the development, maturation, and enlargement of human embryonic brain cells, on the one hand, and increases the percent of cell death, which attests to accelerated maturation and metabolism, on the other.

  12. Effects of heavy ion radiation on the brain vascular system and embryonic development

    Science.gov (United States)

    Yang, T. C.; Tobias, C. A.

    1984-01-01

    The present investigation is concerned with the effects of heavy-ion radiation on the vascular system and the embryonic development, taking into account the results of experiments with neonatal rats and mouse embryos. It is found that heavy ions can be highly effective in producing brain hemorrhages and in causing body deformities. Attention is given to aspects of methodology, the induction of brain hemorrhages by X-rays and heavy ions, and the effect of iron particles on embryonic development. Reported results suggest that high linear energy transfer (LET) heavy ions can be very effective in producing developmental abnormalities.

  13. How does blastomere removal affect embryonic development? : A time-lapse analysis

    DEFF Research Database (Denmark)

    Kirkegaard, Kirstine; Hindkjær, Johnny Juhl; Ingerslev, Hans Jakob

    Introduction: Preimplantation genetic diagnosis (PGD) is offered to couples whose potential offspring are at risk of an inherited single gene disease or structural chromosomal disorder. PGD requires embryonic DNA for establishing the diagnosis, which can be obtained by performing blastomere biopsy...... of the 6-10 cell embryo. It has been argued that blastomere removal does not affect embryonic development, but few studies have focussed on safety of the procedure. Recently, time-lapse studies on mice have suggested that blastomere removal affects embryonic development. The present study was conducted...... at the same time-point as the control group, but had a significantly smaller size (p=0,000) and a thicker zona pellucida (p=0,000) when hatching. In the control group expansion of the blastocyst caused continous thinning of zona pellucida until the blastocyst hatched. In the biopsed group no expansion or zona...

  14. Activation of the Aryl Hydrocarbon Receptor Interferes with Early Embryonic Development

    Directory of Open Access Journals (Sweden)

    Manolis Gialitakis

    2017-11-01

    Full Text Available The transcriptional program of early embryonic development is tightly regulated by a set of well-defined transcription factors that suppress premature expression of differentiation genes and sustain the pluripotent identity. It is generally accepted that this program can be perturbed by environmental factors such as chemical pollutants; however, the precise molecular mechanisms remain unknown. The aryl hydrocarbon receptor (AHR is a widely expressed nuclear receptor that senses environmental stimuli and modulates target gene expression. Here, we have investigated the AHR interactome in embryonic stem cells by mass spectrometry and show that ectopic activation of AHR during early differentiation disrupts the differentiation program via the chromatin remodeling complex NuRD (nucleosome remodeling and deacetylation. The activated AHR/NuRD complex altered the expression of differentiation-specific genes that control the first two developmental decisions without affecting the pluripotency program. These findings identify a mechanism that allows environmental stimuli to disrupt embryonic development through AHR signaling.

  15. Effects of Microgravity on Embryonic Quail Eye Development

    Science.gov (United States)

    Barrett, Joyce E.; Wells, Diane C.; Paulsen, Avelina Q.; Conrad, Gary W.

    1997-01-01

    Immunohistochemical methods were used to stain neurofilament protein in corneal nerves of Embryonic Day 16 (E16) quail eyes that had been fixed in 4% paraformaldehyde at room temperature for several months. Fixation was according to the methods used by the Mir 21/NASA 2 Avian Developmental Biology Flight Experiments for quail embryos incubated on the Mir Space Station. After fixation, corneas were pretreated to improve immunohistochemical visualization of neurofilaments. A sequential combination of three pretreatments [microwave heating in saline G, followed by extraction with sodium dodecyl sulfate (SDS) at 37 C, followed by digestion with hyaluronidase at 37 C], produced increased antibody staining of corneal nerve neurofilament proteins, compared with corneas subjected to no prior pretreatments. Darker nerve staining and increased numbers of fine branches were observed, together with lower background staining after such pretreatments. In contrast, use of any single pretreatment or pair of pretreatments resulted in only slight and inconsistent enhancement of nerve staining. Only the sequential combination of all three pretreatments resulted in consistently better nerve staining.

  16. Embryonic mouse pre-metatarsal development in organ culture

    Science.gov (United States)

    Klement, B. J.; Spooner, B. S.

    1993-01-01

    Embryonic mouse pre-metatarsals were removed from embryos at 13 days of gestation and cultured in a defined, serum-free medium for up to 15 days. By histological analysis, we observe that the cultured pre-metatarsal tissue undergoes a similar developmental profile as pre-metatarsals growing normally in vivo. The initial mesenchyme condensation regions undergo differentiation and morphogenesis to form distinct rods made up of cartilage tissue. A marker of this differentiation step is the synthesis of type II collagen. Metabolic labelling, pepsin digestion, SDS-PAGE, and autoradiography were used to demonstrate this protein when cartilage tissue is present in the cultures. After additional culture time, terminal chondrocyte differentiation and morphogenesis take place in specific regions of the cartilage rods to form bands of hypertrophied chondrocytes. One marker of this differentiation step is the synthesis of the enzyme alkaline phosphatase. We have measured the activity of this enzyme throughout the culture period and see a substantial increase at the time of terminal chondrocyte differentiation. Another feature of hypertrophied chondrocytes is that the matrix around the cells becomes calcified. Calcified matrix in our cultured pre-metatarsals was visualized by staining with alizarin red. By supplementing the defined culture medium with ITS, we observed that terminal chondrocyte differentiation took place in a shorter culture time. Supplementation of the medium with serum results in a similar acceleration of terminal differentiation, and, with additional culture time, an osteoid-like matrix forms around the central region of the rods.

  17. Effects of Hypergravity on Statocyst Development in Embryonic Aplysia californica

    Science.gov (United States)

    Pedrozo, Hugo A.; Wiederhold, Michael L.

    1994-01-01

    Aplysia californica is a marine gastropod mollusc with bilaterally paired statocysts as gravity-reccptor organs. Data from three experiments in which embryonic Aplysia californica were exposed to 2 x g arc discussed. The experimental groups were exposed to excess gravity until hatching (9-12 day), whereas control groups were maintained at normal gravity. Body diameter was measured before exposure to 2 x g. Statocyst, statolith and body diameter were each determined for samples of 20 embryos from each group on successive days. Exposure to excess gravity led to an increase in body size. Statocyst size was not affected by exposure to 2 x g. Statolith size decreased with treatment as indicated by smaller statolith-to-body ratios observed in the 2 x g group in all three experiments. Mean statolith diameter was significantly smaller for the 2 x g group in Experiment 1 but not in Experiments 2 and 3. Defective statocysts, characterized by very small or no statoliths, were found in the 2 x g group in Experiments 1 and 2.

  18. Medical Student Retention of Embryonic Development: Impact of the Dimensions Added by Multimedia Tutorials

    Science.gov (United States)

    Marsh, Karen R.; Giffin, Bruce F.; Lowrie, Donald J., Jr.

    2008-01-01

    The purpose of this project was to develop Web-based learning modules that combine (1) animated 3D graphics; (2) 3D models that a student can manipulate independently; (3) passage of time in embryonic development; and (4) animated 2D graphics, including 2D cross-sections that represent different "slices" of the embryo, and animate in…

  19. Arabidopsis LEAFY COTYLEDON1 controls cell fate determination during post-embryonic development

    Science.gov (United States)

    Huang, Mingkun; Hu, Yilong; Liu, Xu; Li, Yuge; Hou, Xingliang

    2015-01-01

    Arabidopsis LEAFY COTYLEDON1 (LEC1) transcription factor is a master regulator that shapes plant embryo development and post-embryonic seedling establishment. Loss-of-function of LEC1 alters the cotyledon identity, causing the formation of ectopic trichomes, which does not occur in wild-type seedlings, implying that LEC1 might regulate embryonic cell fate determination during post-embryonic development. To test this hypothesis, we compared the expression of trichome development-related genes between the wild-type and the lec1 mutant. We observed that transcripts of GLABROUS1 (GL1), GL2, and GL3, genes encoding the positive regulators in trichome development, were significantly upregulated, while the TRICHOMELESS1 (TCL2), ENHANCER OF TRY AND CPC1 (ETC1), and ETC2 genes, encoding the negative regulators in trichome development, were downregulated in the lec1 mutant. Furthermore, overexpression of LEC1 activated the expressions of TCL2, CAPPICE (CPC), and ETC1, resulting in production of cotyledonary leaves with no or fewer trichomes during vegetative development. In addition, we demonstrated that LEC1 interacts with TCL2 in yeast and in vitro. A genetic experiment showed that loss-of-function of GL2 rescued the ectopic trichome formation in the lec1 mutant. These findings strongly support that LEC1 regulates trichome development, providing direct evidence for the role of LEC1 in cell fate determination during post-embryonic development. PMID:26579186

  20. Identification of Estrogen Target Genes during Zebrafish Embryonic Development through Transcriptomic Analysis

    Science.gov (United States)

    Estrogen signaling is important for vertebrate embryonic development. Here we have used zebrafish (Danio rerio) as a vertebrate model to analyze estrogen signaling during development. Zebrafish embryos were exposed to 1 μM 17β-estradiol (E2) or vehicle from 3 hours to 4 days post...

  1. Globalisation reaches gene regulation: the case for vertebrate limb development.

    Science.gov (United States)

    Zuniga, Aimée

    2005-08-01

    Analysis of key regulators of vertebrate limb development has revealed that the cis-regulatory regions controlling their expression are often located several hundred kilobases upstream of the transcription units. These far up- or down-stream cis-regulatory regions tend to reside within rather large, functionally and structurally unrelated genes. Molecular analysis is beginning to reveal the complexity of these large genomic landscapes, which control the co-expression of clusters of diverse genes by this novel type of long-range and globally acting cis-regulatory region. An increasing number of spontaneous mutations in vertebrates, including humans, are being discovered inactivating or altering such global control regions. Thereby, the functions of a seemingly distant but essential gene are disrupted rather than the closest.

  2. Motorcycle limb injuries in a developing Country | Oluwadiya | West ...

    African Journals Online (AJOL)

    42.2% were due to collision with automobiles, 22% pedestrian while 8.7% were collisions between motorcycles. The use of protective/safety devices was practically non-existent. Seventy-six (66.1%) patients had lower limbs injuries, 25 (21.7%) patients had upper limb injuries while the remaining 14 (12.2%) injured both ...

  3. Paternal identity impacts embryonic development for two species of freshwater fish

    DEFF Research Database (Denmark)

    Siddique, Mohammad Abdul Momin; Linhart, Otomar; Krejszeff, Sławomir

    2017-01-01

    Paternal, compared to maternal, contributions were believed to have only a limited influence on embryonic development and larval fitness traits in fishes. Therefore, the perspective of male influence on early life history traits has come under scrutiny. This study was conducted to determine...... parental effects on the rate of eyed embryos of Ide . Leuciscus idus and Northern pike . Esox lucius. Five sires and five dams from each species were crossed using a quantitative genetic breeding design and the resulting 25 sib groups of each species were reared to the embryonic eyed stage. We...... then partition variation in embryonic phenotypic performance to maternal, paternal, and parental interactions using the Restricted Maximum Likelihood (REML) model. Results showed that paternal, maternal, and the paternal. ×. maternal interaction terms were highly significant for both species; clearly...

  4. A chick embryo cryoinjury model for the study of embryonic organ development and repair.

    Science.gov (United States)

    Palmquist-Gomes, Paul; Guadix, Juan Antonio; Pérez-Pomares, José M

    2016-01-01

    Tissue ablation is a classic experimental approach to study early embryo patterning. However, ablation methods are less frequently used to assess the reparative or regenerative properties of embryonic tissues during organogenesis. Surgical procedures based on the removal of a significant amount of tissue during organ formation very much depend on the skills of the researcher, are difficult to reproduce, and often result in extensive tissue disruption leading to embryonic death. In this paper, we present a new protocol to generate discrete, locally-restricted and highly reproducible wounds in the developing chick embryo using a liquid N2-cooled metallic probe. This in ovo procedure allows for the study of organ-specific tissue responses to damage, such as compensatory cell growth, cell differentiation, and reparative/regenerative mechanisms throughout the embryonic lifespan. Copyright © 2015 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  5. Origin of pluripotent germ cell tumours: the role of microenvironment during embryonic development

    DEFF Research Database (Denmark)

    Kristensen, David Møbjerg; Sonne, Si Brask; Ottesen, Anne Marie

    2008-01-01

    has recently been explained by a close resemblance of their expression profile to that of embryonic inner cell mass cells studied in culture as embryonic stem cells, with high expression of transcription factors associated with pluripotency, such as NANOG and OCT3/4, as well as proteins found...... in several tissue specific stem cells, such as TFAP2C (AP-2gamma) or KIT. CIS and seminomas highly express a number of pre-meiotic germ cell specific genes, which are down-regulated during development to non-seminomas, while the expression of other embryonic markers, such as SOX2, is up......Carcinoma in situ (CIS) testis, known also as intratubular germ cell neoplasia, is the cancer stem cell from which the great majority of testicular germ cell derived tumours (TGCTs) of the testis arise. TGCTs can proliferate into morphologically homogeneous seminomas or can differentiate...

  6. Prenatal imaging of distal limb abnormalities using OCT in mice

    Science.gov (United States)

    Larina, Irina V.; Syed, Saba H.; Dickinson, Mary E.; Overbeek, Paul; Larin, Kirill V.

    2012-01-01

    Congenital abnormalities of the limbs are common birth defects. These include missing or extra fingers or toes, abnormal limb length, and abnormalities in patterning of bones, cartilage or muscles. Optical Coherence Tomography (OCT) is a 3-D imaging modality, which can produce high-resolution (~8 μm) images of developing embryos with an imaging depth of a few millimeters. Here we demonstrate the capability of OCT to perform 3D imaging of limb development in normal embryos and a mouse model with congenital abnormalities. Our results suggest that OCT is a promising tool to analyze embryonic limb development in mammalian models of congenital defects.

  7. [Acceleration of Embryonic Development of Pinus sibirica Trees with a One-Year Reproductive Cycle].

    Science.gov (United States)

    Tret'yakova, I N; Lukina, N V

    2016-01-01

    The study of the formation of embryonic structures in Pinus sibirica forms with a one-year reproductive cycle showed that the acceleration of the embryonic process manifested itself as a reduction of the coenocytic stage of the female gametophyte development (1.5 months instead of 1 year). The egg was not fertilized because of the asynchronous maturation of male and female gametophytes. Seeds without embryos were formed. We assumed that the acceleration of the reproductive process in Pinus sibirica was caused by a mutation in the female generative organs.

  8. Morphological and histological studies on the embryonic development of the freshwater prawn, Macrobrachium rosenbergii (Crustacea, Decapoda

    Directory of Open Access Journals (Sweden)

    Madlen M. Habashy

    2012-05-01

    Full Text Available The present work was carried out to describe the embryonic changes during development of the freshwater prawn Macrobrachium rosenbergii based on some morphological and histological features. In addition the biochemical composition of eggs was investigated during the embryonic development of the studied species. Results revealed that eggs of M. rosenbergii completed their development in 20 days at 28.5 ± 0.45 °C. The present investigation showed that primordial germ cells (PGCs were detected early in the examined embryos. In 6.5 days old embryo, a cluster of PGCs occupied the dorso-medial region behind the yolky portion. In addition, the biochemical data indicated that the protein content was significantly increased, while lipid and carbohydrate contents decreased during the embryonic development. The lowest water content was found in the bright orange eggs and reached its highest level in the deep brown eggs. It was noted that the increase in the water content was correlated with the increase in the egg diameters. It was also concluded that, variations in the biochemical compositions of eggs reflected changes in their morphogenesis during the embryonic development.

  9. Structure and function of gap junction proteins: role of gap junction proteins in embryonic heart development.

    Science.gov (United States)

    Ahir, Bhavesh K; Pratten, Margaret K

    2014-01-01

    Intercellular (cell-to-cell) communication is a crucial and complex mechanism during embryonic heart development. In the cardiovascular system, the beating of the heart is a dynamic and key regulatory process, which is functionally regulated by the coordinated spread of electrical activity through heart muscle cells. Heart tissues are composed of individual cells, each bearing specialized cell surface membrane structures called gap junctions that permit the intercellular exchange of ions and low molecular weight molecules. Gap junction channels are essential in normal heart function and they assist in the mediated spread of electrical impulses that stimulate synchronized contraction (via an electrical syncytium) of cardiac tissues. This present review describes the current knowledge of gap junction biology. In the first part, we summarise some relevant biochemical and physiological properties of gap junction proteins, including their structure and function. In the second part, we review the current evidence demonstrating the role of gap junction proteins in embryonic development with particular reference to those involved in embryonic heart development. Genetics and transgenic animal studies of gap junction protein function in embryonic heart development are considered and the alteration/disruption of gap junction intercellular communication which may lead to abnormal heart development is also discussed.

  10. Impaired embryonic development in mice overexpressing the RNA-binding protein TIAR.

    Directory of Open Access Journals (Sweden)

    Yacine Kharraz

    Full Text Available BACKGROUND: TIA-1-related (TIAR protein is a shuttling RNA-binding protein involved in several steps of RNA metabolism. While in the nucleus TIAR participates to alternative splicing events, in the cytoplasm TIAR acts as a translational repressor on specific transcripts such as those containing AU-Rich Elements (AREs. Due to its ability to assemble abortive pre-initiation complexes coalescing into cytoplasmic granules called stress granules, TIAR is also involved in the general translational arrest observed in cells exposed to environmental stress. However, the in vivo role of this protein has not been studied so far mainly due to severe embryonic lethality upon tiar invalidation. METHODOLOGY/PRINCIPAL FINDINGS: To examine potential TIAR tissue-specificity in various cellular contexts, either embryonic or adult, we constructed a TIAR transgenic allele (loxPGFPloxPTIAR allowing the conditional expression of TIAR protein upon Cre recombinase activity. Here, we report the role of TIAR during mouse embryogenesis. We observed that early TIAR overexpression led to low transgene transmission associated with embryonic lethality starting at early post-implantation stages. Interestingly, while pre-implantation steps evolved correctly in utero, in vitro cultured embryos were very sensitive to culture medium. Control and transgenic embryos developed equally well in the G2 medium, whereas culture in M16 medium led to the phosphorylation of eIF2alpha that accumulated in cytoplasmic granules precluding transgenic blastocyst hatching. Our results thus reveal a differential TIAR-mediated embryonic response following artificial or natural growth environment. CONCLUSIONS/SIGNIFICANCE: This study reports the importance of the tightly balanced expression of the RNA-binding protein TIAR for normal embryonic development, thereby emphasizing the role of post-transcriptional regulations in early embryonic programming.

  11. Correlation between exposure to magnetic fields and embryonic development in the first trimester.

    Directory of Open Access Journals (Sweden)

    Xiu-Juan Su

    Full Text Available OBJECTIVE: To explore the correlation between maternal magnetic field (MF exposure in daily life and embryonic development. METHODS: A cross-sectional study was conducted among 149 pregnant women who were seeking induced abortion of unwanted pregnancies. Participating women were asked to wear an EMDEX Lite magnetic field meter for a 24-h period to obtain MF exposure level within 4 weeks following the abortion. Embryonic bud and sac lengths were measured through B-mode ultrasound before the surgical abortion. Embryo sections were prepared and examined for histological changes, and the apoptosis status of the deciduas was examined using the TUNEL apoptosis assay. RESULTS: Embryonic bud length was inversely associated with maternal daily MF exposure level; the association was statistically significant at the time-weighted-average and 75th percentile of MF exposure levels, with coefficients of -3.09 (P = 0.0479 and -3.07 (P = 0.0228, respectively. Logistic regression for examining the risk of higher MF exposure indicated that women with her 75th percentile of daily MF measurements ≥0.82 mG had a 3.95-fold risk of having a fetus with a shorter embryonic bud length than those whose daily MF exposure were <0.82 mG. MF exposure was associated with a higher degree of apoptosis, but the association was not statistically significant. We failed to find a statistical correlation between MF exposure and embryonic sac length and histological changes in the first trimester. CONCLUSION: Prenatal MF exposure may have an adverse effect on embryonic development.

  12. A new take on an old story: chick limb organ culture for skeletal niche development and regenerative medicine evaluation

    Directory of Open Access Journals (Sweden)

    EL Smith

    2013-09-01

    Full Text Available Scientific research and progress, particularly in the drug discovery and regenerative medicine fields, is typically dependent on suitable animal models to develop new and improved clinical therapies for injuries and diseases. In vivo model systems are frequently utilised, but these models are expensive, highly complex and pose a number of ethical considerations leading to the development and use of a number of alternative ex vivo model systems. The ex vivo embryonic chick long bone and limb bud models have been utilised in the scientific research field as a model to understand skeletal development for over eighty years. The rapid development of avian skeletal tissues, coupled with the ease of experimental manipulation, availability of genome sequence and the presence of multiple cell and tissue types has seen such model systems gain significant research interest in the last few years in the tissue engineering field. The models have been explored both as systems for understanding the developmental bone niche and as potential testing tools for tissue engineering strategies for bone repair and regeneration. This review details the evolution of the chick limb organ culture system and presents recent innovative developments and emerging techniques and technologies applied to these models that are aiding our understanding of skeletal developmental and regenerative medicine research and application.

  13. Lipid content and fatty acid profile during lake whitefish embryonic development at different incubation temperatures.

    Science.gov (United States)

    Mueller, Casey A; Doyle, Liam; Eme, John; Manzon, Richard G; Somers, Christopher M; Boreham, Douglas R; Wilson, Joanna Y

    2017-01-01

    Lipids serve as energy sources, structural components, and signaling molecules during fish embryonic development, and utilization of lipids may vary with temperature. Embryonic energy utilization under different temperatures is an important area of research in light of the changing global climate. Therefore, we examined percent lipid content and fatty acid profiles of lake whitefish (Coregonus clupeaformis) throughout embryonic development at three incubation temperatures. We sampled fertilized eggs and embryos at gastrulation, eyed and fin flutter stages following chronic incubation at temperatures of 1.8, 4.9 and 8.0°C. Hatchlings were also sampled following incubation at temperatures of 3.3, 4.9 and 8.0°C. Fertilized eggs had an initial high percentage of dry mass composed of lipid (percent lipid content; ~29%) consisting of ~20% saturated fatty acids (SFA), ~32% monounsaturated fatty acids (MUFA), ~44% polyunsaturated fatty acids (PUFA), and 4% unidentified. The most abundant fatty acids were 16:0, 16:1, 18:1(n-9c), 20:4(n-6), 20:5(n-3) and 22:6(n-3). This lipid profile matches that of other cold-water fish species. Percent lipid content increased during embryonic development, suggesting protein or other yolk components were preferentially used for energy. Total percentage of MUFA decreased during development, which indicated MUFA were the primary lipid catabolized for energy during embryonic development. Total percentage of PUFA increased during development, driven largely by an increase in 22:6(n-3). Temperature did not influence percent lipid content or percent MUFA at any development stage, and had inconsistent effects on percent SFA and percent PUFA during development. Thus, lake whitefish embryos appear to be highly adapted to low temperatures, and do not alter lipids in response to temperature within their natural incubation conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Proteomic analysis of egg white proteins during the early phase of embryonic development.

    Science.gov (United States)

    Qiu, Ning; Ma, Meihu; Cai, Zhaoxia; Jin, Yongguo; Huang, Xi; Huang, Qun; Sun, Shuguo

    2012-03-16

    Avian egg albumen participates in embryonic development by providing essential nutrients as well as antimicrobial protection. Although various biological functions of egg white proteins were suggested during embryogenesis, global changes of these proteins under incubation conditions remained uninvestigated. This study presents a proteomic analysis on the change of egg white proteins during the first week of embryonic development. By using 2-DE, together with MALDI-TOF MS/MS, thirty protein spots representing eight proteins were identified showing significant changes in abundance during incubation. An accelerating degradation of ovalbumin was observed in a wide range of molecular weight. In addition, four protein complexes were predicted according to the detected molecular weight increase. Among these speculated protein complexes, an ovalbumin spot coupled with RNA-binding protein was detected. The absence of these protein complexes before incubation, followed by the constant increase in abundance during incubation indicates conceivable pivotal roles in embryonic development. To better understand the function of the proteins identified in this study, discrepancies of egg white protein changes between fertilized and unfertilized chicken eggs were additionally demonstrated. These findings will provide insight into the embryogenesis process to improve our knowledge of egg white proteins in regulating and supporting early embryonic development. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Correlation of Versican Expression, Accumulation, and Degradation during Embryonic Development by Quantitative Immunohistochemistry

    Science.gov (United States)

    Snyder, Jessica M.; Washington, Ida M.; Birkland, Timothy; Chang, Mary Y.; Frevert, Charles W.

    2015-01-01

    Versican, a chondroitin sulfate proteoglycan, is important in embryonic development, and disruption of the versican gene is embryonically lethal in the mouse. Although several studies show that versican is increased in various organs during development, a focused quantitative study on versican expression and distribution during lung and central nervous system development in the mouse has not previously been performed. We tracked changes in versican (Vcan) gene expression and in the accumulation and degradation of versican. Vcan expression and quantitative immunohistochemistry performed from embryonic day (E) 11.5 to E15.5 showed peak Vcan expression at E13.5 in the lungs and brain. Quantitative mRNA analysis and versican immunohistochemistry showed differences in the expression of the versican isoforms in the embryonic lung and head. The expression of Vcan mRNA and accumulation of versican in tissues was complementary. Immunohistochemistry demonstrated co-localization of versican accumulation and degradation, suggesting distinct roles of versican deposition and degradation in embryogenesis. Very little versican mRNA or protein was found in the lungs of 12- to 16-week-old mice but versican accumulation was significantly increased in mice with Pseudomonas aeruginosa lung infection. These data suggest that versican plays an important role in fundamental, overlapping cellular processes in lung development and infection. PMID:26385570

  16. Generation of the Dimensional Embryology Application (App) for Visualization of Early Chick and Frog Embryonic Development

    Science.gov (United States)

    Webb, Rebecca L.; Bilitski, James; Zerbee, Alyssa; Symans, Alexandra; Chop, Alexandra; Seitz, Brianne; Tran, Cindy

    2015-01-01

    The study of embryonic development of multiple organisms, including model organisms such as frogs and chicks, is included in many undergraduate biology programs, as well as in a variety of graduate programs. As our knowledge of biological systems increases and the amount of material to be taught expands, the time spent instructing students about…

  17. Differential Requirement for Pten Lipid and Protein Phosphatase Activity during Zebrafish Embryonic Development.

    Science.gov (United States)

    Stumpf, Miriam; den Hertog, Jeroen

    2016-01-01

    The lipid- and protein phosphatase PTEN is one of the most frequently mutated tumor suppressor genes in human cancers and many mutations found in tumor samples directly affect PTEN phosphatase activity. In order to understand the functional consequences of these mutations in vivo, the aim of our study was to dissect the role of Pten phosphatase activities during zebrafish embryonic development. As in other model organisms, zebrafish mutants lacking functional Pten are embryonically lethal. Zebrafish have two pten genes and pten double homozygous zebrafish embryos develop a severe pleiotropic phenotype around 4 days post fertilization, which can be largely rescued by re-introduction of pten mRNA at the one-cell stage. We used this assay to characterize the rescue-capacity of Pten and variants with mutations that disrupt lipid, protein or both phosphatase activities. The pleiotropic phenotype at 4dpf could only be rescued by wild type Pten, indicating that both phosphatase activities are required for normal zebrafish embryonic development. An earlier aspect of the phenotype, hyperbranching of intersegmental vessels, however, was rescued by Pten that retained lipid phosphatase activity, independent of protein phosphatase activity. Lipid phosphatase activity was also required for moderating pAkt levels at 4 dpf. We propose that the role of Pten during angiogenesis mainly consists of suppressing PI3K signaling via its lipid phosphatase activity, whereas the complex process of embryonic development requires lipid and protein phosphatase of Pten.

  18. Storage of Eggs in Water Affects Internal Egg Quality, Embryonic Development, and Hatchling Quality

    NARCIS (Netherlands)

    Brand, van den H.; Reijrink, I.A.M.; Hoekstra, L.A.; Kemp, B.

    2008-01-01

    In a series of experiments, effects of storage of eggs in water on internal egg quality, embryonic development, and hatchling quality were investigated. In experiment 1, unfertilized eggs were stored for 4 to 14 d in water (W) or air (control; C). In experiment 2, fertilized eggs were stored for 3

  19. High-throughput identification of small molecules that affect human embryonic vascular development

    NARCIS (Netherlands)

    Vazão, Helena; Rosa, Susana; Barata, Tânia; Costa, Ricardo; Pitrez, Patrícia R.; Honório, Inês; De Vries, Margreet R.; Papatsenko, Dimitri; Benedito, Rui; Saris, Daniel; Khademhosseini, Ali; Quax, Paul H.A.; Pereira, Carlos F.; Mercader, Nadia; Fernandes, Hugo; Ferreira, Lino

    2017-01-01

    Birth defects, which are in part caused by exposure to environmental chemicals and pharmaceutical drugs, affect 1 in every 33 babies born in the United States each year. The current standard to screen drugs that affect embryonic development is based on prenatal animal testing; however, this approach

  20. Gli1 is not required for Pdgfralpha expression during mouse embryonic development

    NARCIS (Netherlands)

    Zhang, Xiao-Qun; Afink, Gijs B.; Hu, Xin-Rong; Forsberg-Nilsson, Karin; Nistér, Monica

    2005-01-01

    Pdgfra is expressed in the mesenchyme of multiple organs during embryonic development and Pdgfralpha is involved in cell proliferation, differentiation, migration, and apoptosis in many tissues. A fine-tuned regulation of gene transcription is required to achieve these effects. To investigate if the

  1. The effect of oxygen tension on porcine embryonic development is dependent on embryo type

    DEFF Research Database (Denmark)

    Booth, Paul J; Holm, Peter; Callesen, Henrik

    2005-01-01

    Reducing oxygen concentration from atmospheric levels during in vitro culture generally, but not invariably, improves embryonic development across a range of species. Since the few published reports of such an action in the pig are contradictory--perhaps a consequence of the derivation of the emb...

  2. Divergent selection for shape of growth curve in Japanese quail. 2. Embryonic development and growth

    Czech Academy of Sciences Publication Activity Database

    Hyánková, L.; Novotná, Božena; Knížetová, H.; Horáčková, Š.

    2004-01-01

    Roč. 45, č. 2 (2004), s. 171-179 ISSN 0007-1668 R&D Projects: GA ČR GA523/99/1262 Institutional research plan: CEZ:AV0Z5039906 Keywords : embryonic development Subject RIV: EA - Cell Biology Impact factor: 0.677, year: 2004

  3. Hypoxic level and duration differentially affect embryonic organ system development of the chicken (Gallus gallus).

    Science.gov (United States)

    Zhang, H; Burggren, W W

    2012-12-01

    Hypoxia inhibits avian embryonic development, as well as increases embryonic mortality. However, the key organ systems affected by hypoxia, and their critical windows for development, are poorly understood. Consequently, chicken embryos were continuously exposed to 3 levels of oxygen (21, 15, or 13% O(2)) throughout d 0 to 10, d 11 to 18, or d 0 to 18 of incubation, followed by morphometric and blood physiological measurements. Hypoxia occurring early during incubation (d 0 to 10) had larger effects on embryonic mortality and organ growth than hypoxia occurring at later stages (d 10 to 18). Growth of the heart and chorioallantoic membrane was stimulated by chronic hypoxia, whereas the lung, brain, eye, liver, stomach, beak, and toes showed no disruption. Sustained hypoxia from the beginning of incubation decreased blood hemoglobin, hematocrit, and red blood cell concentration of embryos at d 10, but the values among hypoxic and normoxic groups were not significantly different at d 18. Blood partial pressure of O(2) and partial pressure of CO(2) were dependent upon incubation O(2) level at a given day of development. These results indicated that either modest hypoxia (15% O(2)) throughout development, or hypoxia at any level during the late stages (d 11 to 18), increased the heart and chorioallantoic membrane weight, which partly compensated for the detrimental effects of hypoxia on embryonic development. We conclude that the first half of embryonic development contained the critical windows for the detrimental effects of hypoxia, and the second half contained the critical windows for the compensatory response of hypoxia in key organs.

  4. Embryonic muscle development in direct and indirect developing marine flatworms (Platyhelminthes, Polycladida).

    Science.gov (United States)

    Bolaños, D Marcela; Litvaitis, Marian K

    2009-01-01

    We compared embryonic myogenesis of the direct-developing acotylean polyclad Melloplana ferruginea with that of Maritigrella crozieri, a cotylean that develops via a larval stage. Fluorescently labeled F-actin was visualized with laser confocal microscopy. Developmental times are reported as percentages of the time from oviposition to hatching: 7 days for M. crozieri and 22 days for M. ferruginea. The epithelium began to form at 30% development in M. crozieri and at 15% development in M. ferruginea. Random myoblasts appeared in peripheral areas of the embryo at 36% and 22-30% development in M. crozeri and M. ferruginea, respectively. Circular and longitudinal muscle bands formed synchronously at 37-44% development in M. crozieri; yolk obscured observations of early myogenesis in M. ferruginea. An orthogonal muscle grid was established by 45-50% development in both species. Diagonal muscles developed in M. ferruginea at 60-71% development. Hence, juveniles of this species hatch with the same basic body-wall musculature as adults. Larvae of M. crozieri did not hatch with diagonal muscles; these muscles are acquired postmetamorphosis. Additionally, a specialized musculature developed in the larval lobes of M. crozieri. Oral musculature was complex and established by 72% development in both species. Our results are comparable to the muscle differentiation reported for other indirect-developing polyclads and for direct-developing species of macrostomid flatworms. Furthermore, they provide additional support that the orthogonal muscle pattern of circular and longitudinal muscles is a symplesiomorphy of Spiralia.

  5. Color photographic index of fall Chinook salmon embryonic development and accumulated thermal units.

    Directory of Open Access Journals (Sweden)

    James W Boyd

    Full Text Available BACKGROUND: Knowledge of the relationship between accumulated thermal units and developmental stages of Chinook salmon embryos can be used to determine the approximate date of egg fertilization in natural redds, thus providing insight into oviposition timing of wild salmonids. However, few studies have documented time to different developmental stages of embryonic Chinook salmon and no reference color photographs are available. The objectives of this study were to construct an index relating developmental stages of hatchery-reared fall Chinook salmon embryos to time and temperature (e.g., degree days and provide high-quality color photographs of each identified developmental stage. METHODOLOGY/PRINCIPAL FINDINGS: Fall Chinook salmon eggs were fertilized in a hatchery environment and sampled approximately every 72 h post-fertilization until 50% hatch. Known embryonic developmental features described for sockeye salmon were used to describe development of Chinook salmon embryos. A thermal sums model was used to describe the relationship between embryonic development rate and water temperature. Mean water temperature was 8.0 degrees C (range; 3.9-11.7 degrees C during the study period. Nineteen stages of embryonic development were identified for fall Chinook salmon; two stages in the cleavage phase, one stage in the gastrulation phase, and sixteen stages in the organogenesis phase. The thermal sums model used in this study provided similar estimates of fall Chinook salmon embryonic development rate in water temperatures varying from 3.9-11.7 degrees C (mean=8 degrees C to those from several other studies rearing embryos in constant 8 degrees C water temperature. CONCLUSIONS/SIGNIFICANCE: The developmental index provides a reasonable description of timing to known developmental stages of Chinook salmon embryos and was useful in determining developmental stages of wild fall Chinook salmon embryos excavated from redds in the Columbia River. This index

  6. Development of an Upper Limb Motorized Assistive-Rehabilitative Robot

    Science.gov (United States)

    Amiri, Masoud; Casolo, Federico

    While the number of people requiring help for the activities of daily living are increasing, several studies have been shown the effectiveness of robot training for upper limb functionality recovery. The robotic system described in this paper is an active end-effector based robot which can be used for assisting and rehabilitating of human upper limb. The robot is able to take into account desire of the patient for the support that patient needs to complete the task.

  7. Imaging of murine embryonic cardiovascular development using optical coherence tomography (Conference Presentation)

    Science.gov (United States)

    Huang, Yongyang; Degenhardt, Karl R.; Astrof, Sophie; Zhou, Chao

    2016-03-01

    We have demonstrated the capability of spectral domain optical coherence tomography (SDOCT) system to image full development of mouse embryonic cardiovascular system. Monitoring morphological changes of mouse embryonic heart occurred in different embryonic stages helps identify structural or functional cardiac anomalies and understand how these anomalies lead to congenital heart diseases (CHD) present at birth. In this study, mouse embryo hearts ranging from E9.5 to E15.5 were prepared and imaged in vitro. A customized spectral domain OCT system was used for imaging, with a central wavelength of 1310nm, spectral bandwidth of ~100nm and imaging speed of 47kHz A-scans/s. Axial resolution of this system was 8.3µm in air, and transverse resolution was 6.2 µm with 5X objective. Key features of mouse embryonic cardiovascular development such as vasculature remodeling into circulatory system, separation of atria and ventricles and emergence of valves could be clearly seen in three-dimensional OCT images. Optical clearing was applied to overcome the penetration limit of OCT system. With high resolution, fast imaging speed, 3D imaging capability, OCT proves to be a promising biomedical imaging modality for developmental biology studies, rivaling histology and micro-CT.

  8. Stage specific requirement of platelet-derived growth factor receptor-α in embryonic development.

    Science.gov (United States)

    Qian, Chen; Wong, Carol Wing Yan; Wu, Zhongluan; He, Qiuming; Xia, Huimin; Tam, Paul Kwong Hang; Wong, Kenneth Kak Yuen; Lui, Vincent Chi Hang

    2017-01-01

    Platelet-derived growth factor receptor alpha (PDGFRα) is a cell-surface receptor tyrosine kinase for platelet-derived growth factors. Correct timing and level of Pdgfra expression is crucial for embryo development, and deletion of Pdgfra caused developmental defects of multiple endoderm and mesoderm derived structures, resulting in a complex phenotypes including orofacial cleft, spina bifida, rib deformities, and omphalocele in mice. However, it is not clear if deletion of Pdgfra at different embryonic stages differentially affects these structures. To address the temporal requirement of Pdgfra in embryonic development. We have deleted the Pdgfra in Pdgfra-expressing tissues at different embryonic stages in mice, examined and quantified the developmental anomalies. Current study showed that (i) conditional deletion of Pdgfra at different embryonic days (between E7.5 and E10.5) resulted in orofacial cleft, spina bifida, rib cage deformities, and omphalocele, and (ii) the day of Pdgfra deletion influenced the combinations, incidence and severities of these anomalies. Deletion of Pdgfra caused apoptosis of Pdgfra-expressing tissues, and developmental defects of their derivatives. Orofacial cleft, spina bifida and omphalocele are among the commonest skeletal and abdominal wall defects of newborns, but their genetic etiologies are largely unknown. The remarkable resemblance of our conditional Pdgfra knockout embryos to theses human congenital anomalies, suggesting that dysregulated PDGFRA expression could cause these anomalies in human. Future work should aim at defining (a) the regulatory elements for the expression of the human PDGFRA during embryonic development, and (b) if mutations / sequence variations of these regulatory elements cause these anomalies.

  9. Mouse Rad9b is essential for embryonic development and promotes resistance to DNA damage

    Science.gov (United States)

    Leloup, Corinne; Hopkins, Kevin M.; Wang, Xiangyuan; Zhu, Aiping; Wolgemuth, Debra J.; Lieberman, Howard B.

    2010-01-01

    RAD9 participates in promoting resistance to DNA damage, cell cycle checkpoint control, DNA repair, apoptosis, embryogenesis, and regulation of transcription. A paralogue of RAD9 (named RAD9B) has been identified. To define the function of mouse Rad9b (Mrad9b), embryonic stem (ES) cells with a targeted gene deletion were constructed and used to generate Mrad9b mutant mice. Mrad9b−/− embryos are resorbed after E7.5 while some of the heterozygotes die between E12.5 and a few days after birth. Mrad9b is expressed in embryonic brain and Mrad9b+/− embryos exhibit abnormal neural tube closure. Mrad9b−/− mouse embryonic fibroblasts are not viable. Mrad9b−/− ES cells are more sensitive to gamma rays and mitomycin C than Mrad9b+/+ controls, but show normal gamma-ray-induced G2/M checkpoint control. There is no evidence of spontaneous genomic instability in Mrad9b−/− cells. Our findings thus indicate that Mrad9b is essential for embryonic development and mediates resistance to certain DNA damaging agents. PMID:20842695

  10. Sources and timing of calcium mobilization during embryonic development of the corn snake, Pantherophis guttatus.

    Science.gov (United States)

    Stewart, James R; Ecay, Tom W; Blackburn, Daniel G

    2004-11-01

    Embryos of oviparous Reptilia (=turtles, lepidosaurs, crocodilians and birds) extract calcium for growth and development from reserves in the yolk and eggshell. Yolk provides most of the calcium to embryos of lizards and snakes. In contrast, the eggshell supplies most of the calcium for embryonic development of turtles, crocodilians and birds. The yolk sac and chorioallantoic membrane of birds recover and transport calcium from the yolk and eggshell and homologous membranes of squamates (lizards and snakes) probably transport calcium from these two sources as well. We studied calcium mobilization by embryos of the snake Pantherophis guttatus during the interval of greatest embryonic growth and found that the pattern of calcium transfer was similar to other snakes. Calcium recovery from the yolk is relatively low until the penultimate embryonic stage. Calcium removal from the eggshell begins during the same embryonic stage and total eggshell calcium drops in each of the final 2 weeks prior to hatching. The eggshell supplies 28% of the calcium of hatchlings. The timing of calcium transport from the yolk and eggshell is coincident with the timing of growth of the yolk sac and chorioallantoic membrane and expression of the calcium binding protein, calbindin-D28K, in these tissues as reported in previous studies. In the context of earlier work, our findings suggest that the timing and mechanism of calcium transport from the yolk sac of P. guttatus is similar to birds, but that both the timing and mechanism of calcium transport by the chorioallantoic membrane differs. Based on the coincident timing of eggshell calcium loss and embryonic calcium accumulation, we also conclude that recovery of eggshell calcium in P. guttatus is regulated by the embryo.

  11. Forkhead box transcription factors in embryonic heart development and congenital heart disease.

    Science.gov (United States)

    Zhu, Hong

    2016-01-01

    Embryonic heart development is a very complicated process regulated precisely by a network composed of many genes and signaling pathways in time and space. Forkhead box (Fox, FOX) proteins are a family of transcription factors characterized by the presence of an evolutionary conserved "forkhead"or "winged-helix" DNA-binding domain and able to organize temporal and spatial gene expression during development. They are involved in a wide variety of cellular processes, such as cell cycle progression, proliferation, differentiation, migration, metabolism and DNA damage response. An abundance of studies in model organisms and systems has established that Foxa2, Foxc1/c2, Foxh1 and Foxm1, Foxos and Foxps are important components of the signaling pathways that instruct cardiogenesis and embryonic heart development, playing paramount roles in heart development. The previous studies also have demonstrated that mutations in some of the forkhead box genes and the aberrant expression of forkhead box gene are heavily implicated in the congenital heart disease (CHD) of humans. This review primarily focuses on the current understanding of heart development regulated by forkhead box transcription factors and molecular genetic mechanisms by which forkhead box factors modulate heart development during embryogenesis and organogenesis. This review also summarizes human CHD related mutations in forkhead box genes as well as the abnormal expression of forkhead box gene, and discusses additional possible regulatory mechanisms of the forkhead box genes during embryonic heart development that warrant further investigation. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Development of a patient-reported outcome measure for upper limb function in Duchenne muscular dystrophy: DMD Upper Limb PROM.

    Science.gov (United States)

    Klingels, K; Mayhew, A G; Mazzone, E S; Duong, T; Decostre, V; Werlauff, U; Vroom, E; Mercuri, E; Goemans, N M

    2017-02-01

    To develop a patient-reported outcome measure (PROM) assessing upper limb function related to activities of daily living (ADL) that cannot be observed in a clinical setting, specifically for patients with Duchenne muscular dystrophy (DMD) across a wide age range, applicable in the different stages of the disease. The developmental process was based on US Food and Drug Administration guidelines. This included item generation from a systematic review of existing tools and expert opinion on task difficulty and relevance, involving individuals with DMD. Cultural aspects affecting ADL were taken into consideration to make this tool applicable to the broad DMD community. Items were selected in relation to a conceptual framework reflecting disease progression covering the full range of upper limb function across different ADL domains. After pilot testing and iterative Rasch analyses, redundant or clinically irrelevant items were removed. The final questionnaire consists of 32 items covering four domains of ADL (food, self-care, household and environment, leisure and communication). Test-retest reliability was excellent. A DMD-specific upper limb PROM was developed on the basis of clinical relevance and psychometric robustness. Its main purpose is to document the patient self-reported natural history of DMD and assess the efficacy of interventions. © 2016 Mac Keith Press.

  13. The embryonic development of the central American wandering spider Cupiennius salei

    Directory of Open Access Journals (Sweden)

    Hilbrant Maarten

    2011-06-01

    Full Text Available Abstract Background The spider Cupiennius salei (Keyserling 1877 has become an important study organism in evolutionary and developmental biology. However, the available staging system for its embryonic development is difficult to apply to modern studies, with strong bias towards the earliest developmental stages. Furthermore, important embryonic events are poorly understood. We address these problems, providing a new description of the embryonic development of C. salei. The paper also discusses various observations that will improve our understanding of spider development. Results Conspicuous developmental events were used to define numbered stages 1 to 21. Stages 1 to 9 follow the existing staging system for the spider Achaearanea tepidariorum, and stages 10 to 21 provide a high-resolution description of later development. Live-embryo imaging shows cell movements during the earliest formation of embryonic tissue in C. salei. The imaging procedure also elucidates the encircling border between the cell-dense embryo hemisphere and the hemisphere with much lower cell density (a structure termed 'equator' in earlier studies. This border results from subsurface migration of primordial mesendodermal cells from their invagination site at the blastopore. Furthermore, our detailed successive sequence shows: 1 early differentiation of the precheliceral neuroectoderm; 2 the morphogenetic process of inversion and 3 initial invaginations of the opisthosomal epithelium for the respiratory system. Conclusions Our improved staging system of development in C. salei development should be of considerable value to future comparative studies of animal development. A dense germ disc is not evident during development in C. salei, but we show that the gastrulation process is similar to that in spider species that do have a dense germ disc. In the opisthosoma, the order of appearance of precursor epithelial invaginations provides evidence for the non-homology of the

  14. Evaluation of Genes Involved in Limb Development, Angiogenesis, and Coagulation as Risk Factors for Congenital Limb Deficiencies

    Science.gov (United States)

    Browne, Marilyn L.; Carter, Tonia C.; Kay, Denise M.; Kuehn, Devon; Brody, Lawrence C.; Romitti, Paul A.; Liu, Aiyi; Caggana, Michele; Druschel, Charlotte M.; Mills, James L.

    2012-01-01

    We conducted a population-based case-control study of single nucleotide polymorphisms (SNPs) in selected genes to find common variants that play a role in the etiology of limb deficiencies (LD)s. Included in the study were 389 infants with LDs of unknown cause and 980 unaffected controls selected from all births in New York State (NYS) for the years 1998 to 2005. We used cases identified from the NYS Department of Health (DOH) Congenital Malformations Registry. Genotypes were obtained for 132 SNPs in genes involved in limb development (SHH, WNT7A, FGF4, FGF8, FGF10, TBX3, TBX5, SALL4, GREM1, GDF5, CTNNB1, EN1, CYP26A1, CYP26B1), angiogenesis (VEGFA, HIF1A, NOS3), and coagulation (F2, F5, MTHFR). Genotype call rates were >97% and SNPs were tested for departure from Hardy-Weinberg expectations by race/ethnic subgroups. For each SNP, odds ratios (OR)s and confidence intervals (CI)s were estimated and corrected for multiple comparisons for all LDs combined and for LD subtypes. Among non-Hispanic white infants, associations between FGF10 SNPs rs10805683 and rs13170645 and all LDs combined were statistically significant following correction for multiple testing (OR=1.99; 95% CI=1.43-2.77; uncorrected p=0.000043 for rs10805683 heterozygous genotype, and OR=2.37; 95% CI=1.48-3.78; uncorrected p=0.00032 for rs13170645 homozygous minor genotype). We also observed suggestive evidence for associations with SNPs in other genes including CYP26B1 and WNT7A. Animal studies have shown that FGF10 induces formation of the apical ectodermal ridge and is necessary for limb development. Our data suggest that common variants in FGF10 increase the risk for a wide range of non-syndromic limb deficiencies. PMID:22965740

  15. Quantitative proteomics analysis of eggshell membrane proteins during chick embryonic development.

    Science.gov (United States)

    Cordeiro, Cristianne M M; Hincke, Maxwell T

    2016-01-01

    The avian eggshell membrane (ESM) is a meshwork made up of highly cross-linked protein fibers and it is a scaffold upon which biomineralization of the eggshell is initiated. The ESM and associated shell participates in embryonic development by providing physical and chemical protection against pathogen invasion. We performed quantitative proteomic analysis of ESM proteins on multiple days during the three phases of embryonic development. The ESMs were stripped from both fertilized and unfertilized eggs at different days of incubation, and solubilized in a novel manner using TCEP-HCl (Tris (2-carboxyethyl) phosphine hydrochloride). The changes in ESM proteins between occurred during incubation were analyzed. Bioinformatics analysis revealed that of the 12 functional protein clusters identified, protease inhibitors were present at all phases of chick development. A group of proteins involved in calcium binding and oxygen transport were only present during the second phase. Extracellular matrix, cell adhesion proteins related to the vascularization of chorioallantoic membrane (CAM), antimicrobial proteins and proteins involved in the binding and transport of lipids were found in the second and third phases of development. These findings provide insight into the functionality and evolving nature of ESM associated proteins involved in chick embryonic development. The eggshell membranes (ESMs) are a fibrous scaffold that consists of highly crosslinked collagens (types I, V but mainly X), glycoproteins and CREMPs (cysteine-rich eggshell membrane proteins). The ESMs aid in the development of the chick embryo and protect it against pathogen invasion. This biopolymeric fibrous net functions as a platform for nucleation of the calcitic eggshell which provides a primary physical barrier against bacterial ingress. Comparative proteomic analyses of proteins in the ESMs from fertilized eggs and unfertilized eggs showed changes in their levels which varied between the specific

  16. The embryonic development of Schistosoma mansoni eggs: proposal for a new staging system.

    Science.gov (United States)

    Jurberg, Arnon D; Gonçalves, Tiana; Costa, Tatiane A; de Mattos, Ana Carolina A; Pascarelli, Bernardo M; de Manso, Pedro Paulo A; Ribeiro-Alves, Marcelo; Pelajo-Machado, Marcelo; Peralta, José M; Coelho, Paulo Marcos Z; Lenzi, Henrique L

    2009-05-01

    Schistosomiasis is a water-borne parasitic illness caused by neoophoran trematodes of the genus Schistosoma. Using classical histological techniques and whole-mount preparations, the present work describes the embryonic development of Schistosoma mansoni eggs in the murine host and compares it with eggs maintained under in vitro conditions. Two pre-embryonic stages occur inside the female worm: the prezygotic stage is characterized by the release of mature oocytes from the female ovary until its fertilization. The zygotic stage encompasses the migration of the zygote through the ootype, where the eggshell is formed, to the uterus. Fully formed eggs are laid still undeveloped, without having suffered any cleavage. In the outside environment, eight embryonic stages can be defined: stage 1 refers to early cleavages and the beginning of yolk fusion. Stage 2 represents late cleavage, with the formation of a stereoblastula and the onset of outer envelope differentiation. Stage 3 is defined by the elongation of the embryonic primordium and the onset of inner envelope formation. At stage 4, the first organ primordia arise. During stages 5 to 7, tissue and organ differentiation occurs (neural mass, epidermis, terebratorium, musculature, and miracidial glands). Stage 7 is characterized by the nuclear condensation of neurons of the central neural mass. Stage 8 refers to the fully formed larva, presenting muscular contraction, cilia, and flame-cell beating. This staging system was compared to a previous classification and could underlie further studies on egg histoproteomics (morphological localizome). The differentiation of embryonic structures and their probable roles in granulomatogenesis are discussed herein.

  17. Spatial expression of transcription factors in Drosophila embryonic organ development.

    Science.gov (United States)

    Hammonds, Ann S; Bristow, Christopher A; Fisher, William W; Weiszmann, Richard; Wu, Siqi; Hartenstein, Volker; Kellis, Manolis; Yu, Bin; Frise, Erwin; Celniker, Susan E

    2013-12-20

    Site-specific transcription factors (TFs) bind DNA regulatory elements to control expression of target genes, forming the core of gene regulatory networks. Despite decades of research, most studies focus on only a small number of TFs and the roles of many remain unknown. We present a systematic characterization of spatiotemporal gene expression patterns for all known or predicted Drosophila TFs throughout embryogenesis, the first such comprehensive study for any metazoan animal. We generated RNA expression patterns for all 708 TFs by in situ hybridization, annotated the patterns using an anatomical controlled vocabulary, and analyzed TF expression in the context of organ system development. Nearly all TFs are expressed during embryogenesis and more than half are specifically expressed in the central nervous system. Compared to other genes, TFs are enriched early in the development of most organ systems, and throughout the development of the nervous system. Of the 535 TFs with spatially restricted expression, 79% are dynamically expressed in multiple organ systems while 21% show single-organ specificity. Of those expressed in multiple organ systems, 77 TFs are restricted to a single organ system either early or late in development. Expression patterns for 354 TFs are characterized for the first time in this study. We produced a reference TF dataset for the investigation of gene regulatory networks in embryogenesis, and gained insight into the expression dynamics of the full complement of TFs controlling the development of each organ system.

  18. Final Report for Regulation of Embryonic Development in Higher Plants

    Energy Technology Data Exchange (ETDEWEB)

    Harada, John J. [University of California, Davis

    2013-10-22

    The overall goal of the project was to define the cellular processes that underlie embryo development in plants at a mechanistic level. Our studies focused on a critical transcriptional regulator, Arabidopsis LEAFY COTYLEDON (LEC1), that is necessary and sufficient to induce processes required for embryo development. Because LEC1 regulates lipid accumulation during the maturation phase of embryo development, information about LEC1 may be useful in designing approaches to enhance biofuel production in plants. During the tenure of this project, we determined the molecular mechanisms by which LEC1 acts as a transcription factor in embryos. We also identified genes directly regulated by LEC1 and showed that many of these genes are involved in maturation processes. This information has been useful in dissecting the gene regulatory networks controlling embryo development. Finally, LEC1 is a novel isoform of a transcription factor that is conserved among eukaryotes, and LEC1 is active primarily in seeds. Therefore, we determined that the LEC1-type transcription factors first appeared in lycophytes during land plant evolution. Together, this study provides basic information that has implications for biofuel production.

  19. Maternal dietary effects on embryonic ovarian development in cattle

    Science.gov (United States)

    Ovarian gametogenesis and folliculogenesis begins early in fetal development with peak numbers of follicles present in bovine fetal ovaries in the second trimester of gestation and may be altered by maternal nutrition. The objective was to determine whether maternal dietary energy intake by replacem...

  20. Magnetic resonance microscopy atlas of equine embryonic development

    NARCIS (Netherlands)

    Jenner, F; Närväinen, J; de Ruijter-Villani, M; Stout, T A E; van Weeren, P R; Brama, P

    2014-01-01

    REASONS FOR PERFORMING STUDY: Equine embryogenesis post implantation is not well studied, and only two-dimensional illustrations are available. A thorough appreciation of the complex three-dimensional relationship between tissues and organs and their development is, however, crucial for

  1. Characterizing mobility from the prosthetic limb user's perspective: Use of focus groups to guide development of the Prosthetic Limb Users Survey of Mobility.

    Science.gov (United States)

    Hafner, Brian J; Morgan, Sara J; Abrahamson, Daniel C; Amtmann, Dagmar

    2016-10-01

    Input from target respondents in the development of patient-reported outcome measures is necessary to ensure that the instrument is meaningful. To solicit perspectives of prosthetic limb users about their mobility experiences and to inform development of the Prosthetic Limb Users Survey of Mobility. Qualitative study. Four focus groups of lower limb prosthesis users were held in different regions of the United States. Focus group transcripts were coded, and themes were identified. Feedback from participants was used to develop a framework for measuring mobility with a lower limb prosthesis. Focus group participants (N = 37) described mobility as a confluence of factors that included characteristics of the individual, activity, and environment. Identified themes were defined as individual characteristics, forms of movement, and environmental situations. Prosthetic mobility was conceptualized as movement activities performed in an environmental or situational context. Respondent feedback used to guide development of Prosthetic Limb Users Survey of Mobility established a foundation for a new person-centered measure of mobility with a prosthetic limb. Perspectives of target respondents are needed to guide development of instruments intended to measure health outcomes. Focus groups of prosthetic limb users were conducted to solicit experiences related to mobility with a lower limb prosthesis. Results were used to inform development of a clinically meaningful, person-centered instrument. © The International Society for Prosthetics and Orthotics 2015.

  2. Brain Activity at the Embryonic Stages of Development

    Directory of Open Access Journals (Sweden)

    D.R. Akhmetshina

    2015-06-01

    Full Text Available The main function of our brain is to run internal models of the external world. These models enable us to analyze complex sensory inputs from the outside and our bodies, as well as to generate a system of commands underlying our behavior. This is implemented by a complex network, which is built out of billions of interconnected neurons. The network is formed during the ontogeny with the most intense phase of synaptogenesis starting during second half of gestation in the utero. So, the neonate is born with a remarkably developed frame of the central nervous system capable of receiving, processing, and memorizing information from the external world. This review discusses how the brain operates during the fetal stages of development and how the early activities expressed in the fetal brain contribute to the prenatal assembly of the nervous system.

  3. Importance of Endogenous Atrial and Brain Natriuretic Peptides in Murine Embryonic Vascular and Organ Development.

    Science.gov (United States)

    Tokudome, Takeshi; Kishimoto, Ichiro; Shindo, Takayuki; Kawakami, Hayato; Koyama, Teruhide; Otani, Kentaro; Nishimura, Hirohito; Miyazato, Mikiya; Kohno, Masakazu; Nakao, Kazuwa; Kangawa, Kenji

    2016-01-01

    Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) bind to the receptor guanylyl cyclase (GC)-A, leading to diuresis, natriuresis, and blood vessel dilation. In addition, ANP and BNP have various angiogenic properties in ischemic tissue. When breeding mice devoid of GC-A, we noted significant skewing of the Mendelian ratio in the offspring, suggesting embryonic lethality due to knockout of GC-A. Consequently, we here investigated the roles of endogenous ANP and BNP in embryonic neovascularization and organ morphogenesis. Embryos resulting from GC-A(-/-) × GC-A(+/-) crosses developed hydrops fetalis (HF) beginning at embryonic day (E)14.5. All embryos with HF had the genotype GC-A(-/-). At E17.5, 33.3% (12 of 36) of GC-A(-/-) embryos had HF, and all GC-A(-/-) embryos with HF were dead. Beginning at E16.0, HF-GC-A(-/-) embryos demonstrated poorly developed superficial vascular vessels and sc hemorrhage, the fetal side of the placenta appeared ischemic, and vitelline vessels on the yolk sac were poorly developed. Furthermore, HF-GC-A(-/-) embryos also showed abnormal constriction of umbilical cord vascular vessels, few cardiac trabeculae and a thin compact zone, hepatic hemorrhage, and poor bone development. Electron microscopy of E16.5 HF-GC-A(-/-) embryos revealed severe vacuolar degeneration in endothelial cells, and the expected 3-layer structure of the smooth muscle wall of the umbilical artery was indistinct. These data demonstrate the importance of the endogenous ANP/BNP-GC-A system not only in the neovascularization of ischemic tissues but also in embryonic vascular development and organ morphogenesis.

  4. Embryonic development of Ampheres leucopheus and Iporangaia pustulosa (Arachnida: Opiliones: Gonyleptidae).

    Science.gov (United States)

    Gnaspini, Pedro; Lerche, Cristiano Frederico

    2010-09-15

    The first studies concerning the embryonic development of harvestmen started in the late 19th century, and focused mostly on holarctic species, and only three species of the suborder Laniatores (the largest, among the four suborders considered presently) were studied. Moreover, the last studies on embryology of harvestmen were made during the late 1970s. This study focused on the embryonic development of Ampheres leucopheus (Gonyleptidae, Caelopyginae) and Iporangaia pustulosa (Gonyleptidae, Progonyleptoidellinae). The embryonic development was followed in the field, by taking daily photographs of different eggs during about 2 months. When laid, eggs of A. leucopheus and I. pustulosa have approximately 1.13 and 1.30 mm in diameter, respectively, and the second is embedded in a large amount of mucus. The eggs grow, mainly due to water absorption at the beginning of the process, and they reach a diameter of about 1.35 and 1.59 mm, respectively, close to hatching. It took, respectively, 29-56 days and 35-66 days from egg laying to hatching. For the description of the embryonic development, we use photographs from the field, SEM micrographs, and histological analysis. This allowed us, for instance, to document the progression of structures and pigmentation directly from live embryos in the field, and to record microstructures, such as the presence of perforations in the cuticle of the embryo in the place where eyes are developing. Yet, contrary to what was expected in the literature, we record an egg tooth in one of the studied laniatoreans. (c) 2010 Wiley-Liss, Inc.

  5. The influence of temperature on the embryonic development of the annual fish Cynopoecilus melanotaenia (Cyprinodontiformes, Rivulidae

    Directory of Open Access Journals (Sweden)

    A. ARENZON

    Full Text Available The present study aims to provide data about the time required for Cynopoecilus melanotaenia kept at different temperatures to complete embryonic development. This information can be valuable for optimizing laboratory culture and facilitating future use of this species as a test organism in toxicity tests. Temperature effects on hatching rate are presented as well as information related to embryonic development stages. Eggs were observed daily, from start to finish of embryonic development. Thirteen developmental stages were described. Eggs were kept at two constant temperatures (20°C and 25°C and at a variable ambient temperature (16-25°C - mean = 21°C, sd = 1.95, to determine developmental rate (velocity at each temperature. A shorter incubation period was necessary to complete development at 25° ± 1°C. However, all embryos kept at this temperature hatched with morphological defects, which prevented their survival. No significant difference in developmental time period (p = 0.05 was observed at the 20°C and 16°-25°C (mean = 21°C, sd = 1.95 temperatures.

  6. Cadherins in cerebellar development: translation of embryonic patterning into mature functional compartmentalization.

    Science.gov (United States)

    Redies, Christoph; Neudert, Franziska; Lin, Juntang

    2011-09-01

    Cadherins are cell adhesion molecules with multiple morphogenic functions in brain development, for example, in neuroblast migration and aggregation, axon navigation, neural circuit formation, and synaptogenesis. More than 100 members of the cadherin superfamily are expressed in the developing and mature brain. Most of the cadherins investigated, in particular classic cadherins and δ-protocadherins, are expressed in the cerebellum. For several cadherin subtypes, expression begins at early embryonic stages and persists until mature stages of cerebellar development. At intermediate stages, distinct Purkinje cell clusters exhibit unique rostrocaudal and mediolateral expression profiles for each cadherin. In the chicken, mouse, and other species, the Purkinje cell clusters are separated by intervening raphes of migrating granule cells. This pattern of Purkinje cell clusters/raphes is, at least in part, continuous with the parasagittal striping pattern that is apparent in the mature cerebellar cortex, for example, for zebrin II/aldolase C. Moreover, subregions of the deep cerebellar nuclei, vestibular nuclei and the olivary complex also express cadherins differentially. Neuroanatomical evidence suggests that the nuclear subregions and cortical domains that express the same cadherin subtype are connected to each other, to form neural subcircuits of the cerebellar system. Cadherins thus provide a molecular code that specifies not only embryonic structures but also functional cerebellar compartmentalization. By following the implementation of this code, it can be revealed how mature functional architecture emerges from embryonic patterning during cerebellar development. Dysfunction of some cadherins is associated with psychiatric diseases and developmental impairments and may also affect cerebellar function.

  7. Effect of temperature during embryonic development and first feeding of Trichogaster leeri larvae.

    Science.gov (United States)

    Pereira, Samuel Louzada; de Andrade, Dalcio Ricardo; Radael, Marcella Costa; Fosse Filho, João Carlos; de Azevedo, Rafael Vieira; Mattos, Douglas da Cruz; Vidal Junior, Manuel Vazquez

    2016-10-01

    Temperature is an environmental factor that influences the development of fish, and when changed abruptly can lead to high mortality. Some species of fish are influenced by this factor, exhibiting a longer time for embryonic development and time to first feeding. This study aims to evaluate the effect of water temperature on embryonic and larval development up to first feeding, to describe the time in hours post fertilization (hpf) of the emergence of different structures and to determine the best hatching rate and survival of animals under different treatments. Five different egg incubation temperatures were used (24, 26, 28, 30 or 32°C, respectively). The eggs were observed at regular intervals of 30 min up to 24 h, every 2 h until 48 h and every 4 h until the display of first feeding in all treatments. Embryonic development was longer for eggs incubated at 24°C and the best results for hatching rate and survival of spawning efficiency were at 28°C. We recommend that incubation of Trichogaster leeri eggs is carried out at 28°C up to the first feeding of larvae.

  8. Embryonic development of the alimentary canal of the scorpionfly Panorpa obtusa Cheng (Mecoptera: Panorpidae).

    Science.gov (United States)

    Yue, Chao; Hua, Baozhen

    2013-05-01

    The embryonic origin of the alimentary canal, especially the midgut, is a controversial problem in insects, and it has not been satisfactorily resolved to date. The organogenesis of the digestive system in the embryonic development was observed in the scorpionfly Panorpa obtusa Cheng using light, transmission, and scanning electron microscopy. The embryonic development lasts about 150-160 h at 24°C. The stomodaeum is formed from an invagination in the medioposterior portion of the protocephalon mid-ventrally posterior to the labral segment at 76 h after oviposition. The proctodaeum arises as an invagination from the caudal end of the abdomen at 78 h. Four anal forks are formed from within the opening of proctodaeum. Three pairs of proctodaeal evaginations are formed from the anterior part of the proctodaeum, and eventually developing into Malpighian tubules, thus are of ectodermal origin. The cardiac and pyloric valves develop from stomodaeum and proctodaeum, respectively, and also of ectodermal origin. The midgut epithelium originates from anterior and posterior midgut rudiments in blind ends of the stomodaeum and proctodaeum, and it is of endodermal origin. The two cell-bands (rudiments) cover the yolk ventrally and then dorsally, elongate to each other, and eventually fuse to form the midgut. The midgut formation pattern is briefly discussed in different insects. Copyright © 2013 Wiley Periodicals, Inc.

  9. The solid state environment orchestrates embryonic development and tissue remodeling

    Science.gov (United States)

    Damsky, C. H.; Moursi, A.; Zhou, Y.; Fisher, S. J.; Globus, R. K.

    1997-01-01

    Cell interactions with extracellular matrix and with other cells play critical roles in morphogenesis during development and in tissue homeostasis and remodeling throughout life. Extracellular matrix is information-rich, not only because it is comprised of multifunctional structural ligands for cell surface adhesion receptors, but also because it contains peptide signaling factors, and proteinases and their inhibitors. The functions of these groups of molecules are extensively interrelated. In this review, three primary cell culture models are described that focus on adhesion receptors and their roles in complex aspects of morphogenesis and remodeling: the regulation of proteinase expression by fibronectin and integrins in synovial fibroblasts; the regulation of osteoblast differentiation and survival by fibronectin, and the regulation of trophoblast differentiation and invasion by integrins, cadherins and immunoglobulin family adhesion receptors.

  10. Embryonic exposure to sodium arsenite perturbs vascular development in zebrafish.

    Science.gov (United States)

    McCollum, Catherine W; Hans, Charu; Shah, Shishir; Merchant, Fatima A; Gustafsson, Jan-Åke; Bondesson, Maria

    2014-07-01

    Exposure to arsenic in its inorganic form, arsenite, causes adverse effects to many different organs and tissues. Here, we have investigated arsenite-induced adverse effects on vascular tissues in the model organism zebrafish, Danio rerio. Zebrafish embryos were exposed to arsenite at different exposure windows and the susceptibility to vascular tissue damage was recorded at 72hours post fertilization (hpf). Intersegmental vessel sprouting and growth was most perturbed by exposure to arsenite during the 24-48hpf window, while disruption in the condensation of the caudal vein plexus was more often observed at the 48-72hpf exposure window, reflecting when these structures develop during normal embryogenesis. The vascular growth rate was decreased by arsenite exposure, and deviated from that of control embryos at around 24-26.5hpf. We further mapped changes in expression of key regulators of angiogenesis and vasculogenesis. Downregulation of vascular endothelial growth factor receptor 1/fms-related tyrosine kinase 1 (vegfr1/flt1) expression was evident already at 24hpf, coinciding with the decreased vascular growth rate. At later time points, matrix metalloproteinase 9 (mmp9) expression was upregulated, suggesting that arsenite affects the composition of the extracellular matrix. In total, the expression of eight key factors involved in different aspects of vascularization was significantly altered by arsenic exposure. In conclusion, our results show that arsenite is a potent vascular disruptor in the developing zebrafish embryo, a finding that calls for an evaluation of arsenite as a developmental vascular toxicant in mammalian model systems. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Identification of estrogen target genes during zebrafish embryonic development through transcriptomic analysis.

    Directory of Open Access Journals (Sweden)

    Ruixin Hao

    Full Text Available Estrogen signaling is important for vertebrate embryonic development. Here we have used zebrafish (Danio rerio as a vertebrate model to analyze estrogen signaling during development. Zebrafish embryos were exposed to 1 µM 17β-estradiol (E2 or vehicle from 3 hours to 4 days post fertilization (dpf, harvested at 1, 2, 3 and 4 dpf, and subjected to RNA extraction for transcriptome analysis using microarrays. Differentially expressed genes by E2-treatment were analyzed with hierarchical clustering followed by biological process and tissue enrichment analysis. Markedly distinct sets of genes were up and down-regulated by E2 at the four different time points. Among these genes, only the well-known estrogenic marker vtg1 was co-regulated at all time points. Despite this, the biological functional categories targeted by E2 were relatively similar throughout zebrafish development. According to knowledge-based tissue enrichment, estrogen responsive genes were clustered mainly in the liver, pancreas and brain. This was in line with the developmental dynamics of estrogen-target tissues that were visualized using transgenic zebrafish containing estrogen responsive elements driving the expression of GFP (Tg(5xERE:GFP. Finally, the identified embryonic estrogen-responsive genes were compared to already published estrogen-responsive genes identified in male adult zebrafish (Gene Expression Omnibus database. The expressions of a few genes were co-regulated by E2 in both embryonic and adult zebrafish. These could potentially be used as estrogenic biomarkers for exposure to estrogens or estrogenic endocrine disruptors in zebrafish. In conclusion, our data suggests that estrogen effects on early embryonic zebrafish development are stage- and tissue- specific.

  12. Phenotypic Mapping of The Chicken Embryonic Thymic Microenvironment Developing Within an Organ Culture System

    OpenAIRE

    Davidson, Natalie J.; Boyd, Richard L.

    1993-01-01

    The chicken thymic microenvironment, as it developed in an embryonic thymus organ culture system, was phenotypically mapped using a panel of mAb defining both epithelial and nonepithelial stromal cell antigens. We have previously reported that thymocyte proliferation and differentiation will proceed for up to 6–8 days in thymus organ culture, hence demonstrating the functional integrity of the thymic microenvironment in vitro. During this time, the stromal component reflected that of the norm...

  13. Embryonic development in Arabidopsis thaliana: from the zygote division to the shoot meristem

    Directory of Open Access Journals (Sweden)

    Sonia eBoscá

    2011-12-01

    Full Text Available Postembryonic organ formation of plants is fueled with cells from the stem cell niches in the shoot and root meristems. During the last two decades considerable progress has been made in identifying factors that regulate stem cell maintenance. With these factors in hand, the mechanisms establishing stem cell niches during embryo development can be addressed. Here we discuss current models of how the shoot meristem stem cell niche arises during embryonic pattern formation.

  14. Brood parasite and host eggshells undergo similar levels of decalcification during embryonic development

    Czech Academy of Sciences Publication Activity Database

    Igic, B.; Hauber, M. E.; Moskát, C.; Grim, T.; Shawkey, M. D.; Procházka, Petr; Honza, Marcel

    2017-01-01

    Roč. 301, č. 3 (2017), s. 165-173 ISSN 0952-8369 R&D Projects: GA ČR(CZ) GAP506/12/2404 Institutional support: RVO:68081766 Keywords : Acrocephalus arundinaceus * brood parasitism * Cuculus canorus * decalcification * eggshell thickness * embryonic development * common cuckoo * scanning electron microscopy Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 2.186, year: 2016

  15. Limb, tooth, beak: Three modes of development and evolutionary ...

    Indian Academy of Sciences (India)

    2014-03-15

    Mar 15, 2014 ... novelties) can occur with small changes in system parameters induced by a genetic change, or by an environmental factor whose effects can be .... fact act in a mitogenic capacity, indirectly influencing digit number by its control of limb bud ...... oscillation (in segmentation; Oates et al. 2012), and reaction-.

  16. Limb, tooth, beak: Three modes of development and evolutionary ...

    Indian Academy of Sciences (India)

    2014-03-15

    Mar 15, 2014 ... rearrangement of multiple tissue primordia, abrupt appearance of qualitatively different forms (i.e. morphological novelties) can occur with small ... of signals in an active fashion: they are what physicists term excitable media ... the shaping of the limb bud (before the appearance of the endoskeleton), allows ...

  17. Early first trimester maternal ‘high fish and olive oil and low meat’ dietary pattern is associated with accelerated human embryonic development

    NARCIS (Netherlands)

    Parisi, Francesca; Rousian, Melek; Steegers-Theunissen, Régine P.M.; Koning, Anton H.J.; Willemsen, Sten P.; Vries, de Jeanne H.M.; Cetin, Irene; Steegers, Eric A.P.

    2018-01-01

    Background/objectives: Maternal dietary patterns were associated with embryonic growth and congenital anomalies. We aim to evaluate associations between early first trimester maternal dietary patterns and embryonic morphological development among pregnancies with non-malformed outcome.

  18. Revised upper limb module for spinal muscular atrophy: Development of a new module.

    Science.gov (United States)

    Mazzone, Elena S; Mayhew, Anna; Montes, Jacqueline; Ramsey, Danielle; Fanelli, Lavinia; Young, Sally Dunaway; Salazar, Rachel; De Sanctis, Roberto; Pasternak, Amy; Glanzman, Allan; Coratti, Giorgia; Civitello, Matthew; Forcina, Nicola; Gee, Richard; Duong, Tina; Pane, Marika; Scoto, Mariacristina; Pera, Maria Carmela; Messina, Sonia; Tennekoon, Gihan; Day, John W; Darras, Basil T; De Vivo, Darryl C; Finkel, Richard; Muntoni, Francesco; Mercuri, Eugenio

    2017-06-01

    There is a growing need for a robust clinical measure to assess upper limb motor function in spinal muscular atrophy (SMA), as the available scales lack sensitivity at the extremes of the clinical spectrum. We report the development of the Revised Upper Limb Module (RULM), an assessment specifically designed for upper limb function in SMA patients. An international panel with specific neuromuscular expertise performed a thorough review of scales currently available to assess upper limb function in SMA. This review facilitated a revision of the existing upper limb function scales to make a more robust clinical scale. Multiple revisions of the scale included statistical analysis and captured clinically relevant changes to fulfill requirements by regulators and advocacy groups. The resulting RULM scale shows good reliability and validity, making it a suitable tool to assess upper extremity function in the SMA population for multi-center clinical research. Muscle Nerve 55: 869-874, 2017. © 2016 Wiley Periodicals, Inc.

  19. Mechanisms of vertebrate embryo segmentation: Common themes in trunk and limb development.

    Science.gov (United States)

    Sheeba, Caroline J; Andrade, Raquel P; Palmeirim, Isabel

    2016-01-01

    Various ultradian rhythms ensure proper temporal regulations during embryo development. The embryo molecular clock, which was first identified in the presomitic mesoderm (PSM) underlying periodic somite formation, is one among them. Somites are the earliest manifestation of the segmented vertebrate body and they are formed with strict temporal precision. The tetrapod limb is also a segmented structure and the formation of limb bone elements have also been associated with a molecular clock, operating in the distal limb mesenchyme. In both the PSM and the distal limb mesenchyme, the molecular clock (MC) is influenced by FGF, SHH and RA, which are also the key regulators of the development of these tissues. While somitogenesis has been continuously scrutinized to understand the mechanisms of the MC, the limb bud has served as an outstanding paradigm to study how a cohort of undifferentiated cells is organized into functional 3D structures. The fact that both the trunk and limb development are shaped by the MC and by common signaling molecules has prompted the exciting possibility of establishing parallelisms between somitogenesis and limb development. Systematically correlating various parameters during trunk and limb development will help us to appreciate the common principles underlying segmented structure formation and allow the rise of new questions in order to fill the gaps in our present understanding. In this review we have established the parallelisms between somitogenesis and limb development at the level of gene expression patterns and their regulation. Finally, we have also discussed the most evident new avenues this exercise could open to the scientific community. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Development of buffalo (Bubalus bubalis embryonic stem cell lines from somatic cell nuclear transferred blastocysts

    Directory of Open Access Journals (Sweden)

    Syed Mohmad Shah

    2015-11-01

    Full Text Available We developed buffalo embryonic stem cell lines from somatic cell nuclear transfer derived blastocysts, produced by hand-guided cloning technique. The inner cell mass of the blastocyst was cut mechanically using a Microblade and cultured onto feeder cells in buffalo embryonic stem (ES cell culture medium at 38 °C in a 5% CO2 incubator. The stem cell colonies were characterized for alkaline phosphatase activity, karyotype, pluripotency and self-renewal markers like OCT4, NANOG, SOX2, c-Myc, FOXD3, SSEA-1, SSEA-4, TRA-1-60, TRA-1-81 and CD90. The cell lines also possessed the capability to differentiate across all the three germ layers under spontaneous differentiation conditions.

  1. NG2 glia are required for vessel network formation during embryonic development.

    Science.gov (United States)

    Minocha, Shilpi; Valloton, Delphine; Brunet, Isabelle; Eichmann, Anne; Hornung, Jean-Pierre; Lebrand, Cecile

    2015-12-10

    The NG2(+) glia, also known as polydendrocytes or oligodendrocyte precursor cells, represent a new entity among glial cell populations in the central nervous system. However, the complete repertoire of their roles is not yet identified. The embryonic NG2(+) glia originate from the Nkx2.1(+) progenitors of the ventral telencephalon. Our analysis unravels that, beginning from E12.5 until E16.5, the NG2(+) glia populate the entire dorsal telencephalon. Interestingly, their appearance temporally coincides with the establishment of blood vessel network in the embryonic brain. NG2(+) glia are closely apposed to developing cerebral vessels by being either positioned at the sprouting tip cells or tethered along the vessel walls. Absence of NG2(+) glia drastically affects the vascular development leading to severe reduction of ramifications and connections by E18.5. By revealing a novel and fundamental role for NG2(+) glia, our study brings new perspectives to mechanisms underlying proper vessels network formation in embryonic brains.

  2. Effects of quillaja saponin (Quillaja saponaria) on early embryonic zebrafish (Danio rerio) development.

    Science.gov (United States)

    Hassan, Sherif M; Moussa, Eid A; Abbott, Louise C

    2008-01-01

    Although much attention has focused on environmental contamination by heavy metals, pesticides, and polychlorinated biphenyls, potential deleterious effects of naturally occurring organic compounds have received much less consideration. Saponins, which are glycosides found in many plants, are important, environmentally ubiquitous organic compounds. Saponins have both beneficial and deleterious effects in adults, but little is known about how saponins effect early vertebrate embryonic development. The authors tested the toxicity of quillaja saponin using a zebrafish embryo assay. Quillaja saponin, extracted from bark of the tree, Quillaja saponaria, is a common foaming agent used in foods and beverages. At 6 h post fertilization, zebrafish embryos were exposed to five concentrations (0 [negative control], 1, 5, 10 or 20 micro g) of quillaja saponin per milliliter of medium. Zebrafish embryos exposed to 2% ethanol were positive controls (100% embryonic death). Embryos were assessed at 30, 54, and 72 h post fertilization for changes in embryonic development, mortality, time of hatching, and morphological deformities. Embryos exposed to 1 and 5 micro g saponin were healthy, showed no obvious deformities, but exhibited shrinkage of the chorion. Hatching time for zebrafish embryos exposed to 1 and 5 micro g/ml saponin decreased by 18 h compared to unexposed embryos. Zebrafish embryos treated with 5 micro g/ml saponin responded less to touch than embryos treated with 1 micro g/ml saponin or controls. Zebrafish embryos exposed to more than 5 micro g/ml saponin exhibited 100% embryonic mortality. These results indicate that exposure to 5 micro g/ml or less of quillaja saponin acts as a growth promoter, whereas concentrations of 10 micro g/ml or greater are lethal.

  3. Limb anomalies

    DEFF Research Database (Denmark)

    Gurrieri, Fiorella; Kjær, Klaus Wilbrandt; Sangiorgi, Eugenio

    2002-01-01

    In this review we describe the developmental mechanisms involved in the making of a limb, by focusing on the nature and types of interactions of the molecules that play a part in the regulation of limb patterning and characterizing clinical conditions that are known to result from the abnormal...... of limb development has been conserved for more than 300 millions years, with all the necessary adaptive modifications occurring throughout evolution, we also take into consideration the evolutionary aspects of limb development in terms of genetic repertoire, molecular pathways, and morphogenetic events....

  4. L1 arrest, daf-16/FoxO and nonautonomous control of post-embryonic development.

    Science.gov (United States)

    Kaplan, Rebecca E W; Baugh, L Ryan

    2016-01-01

    Post-embryonic development is governed by nutrient availability. L1 arrest, dauer formation and aging illustrate how starvation, anticipation of starvation and caloric restriction have profound influence on C. elegans development, respectively. Insulin-like signaling through the Forkhead box O transcription factor daf-16/FoxO regulates each of these processes. We recently reported that ins-4, ins-6 and daf-28 promote L1 development from the intestine and chemosensory neurons, similar to their role in dauer development. daf-16 functions cell-nonautonomously in regulation of L1 arrest, dauer development and aging. Discrepancies in daf-16 sites of action have been reported in each context, but the consensus implicates epidermis, intestine and nervous system. We suggest technical limitations of the experimental approach responsible for discrepant results. Steroid hormone signaling through daf-12/NHR is known to function downstream of daf-16 in control of dauer development, but signaling pathways mediating cell-nonautonomous effects of daf-16 in aging and L1 arrest had not been identified. We recently showed that daf-16 promotes L1 arrest by inhibiting daf-12/NHR and dbl-1/TGF-β Sma/Mab signaling, two pathways that promote L1 development in fed larvae. We will review these results on L1 arrest and speculate on why there are so many signals and signaling centers regulating post-embryonic development.

  5. [Zebrafish-a new animal models of anterior segment embryonic development and diseases basic research].

    Science.gov (United States)

    Hao, Yong-na; Wei, Rui-hua; Zhao, Shao-zhen

    2012-01-01

    In recent years, zebrafish has become ideal animal models of human disease with its unique characteristics, such as small body, fecundity, fast development and growth, embryo transparency, and so on. Furthermore, the structure and gene of zebrafish eye are highly conservative with human eye, which make ophthalmologists to pay close attention to zebrafish. This review focus on the studies and applications on zebrafish embryonic development of anterior segment, including the morphogenesis of cornea, lens and anterior chamber, and diseases of anterior segment (corneal diseases, cataract, glaucoma).

  6. DLX5, FGF8 and the Pin1 isomerase control ΔNp63α protein stability during limb development: a regulatory loop at the basis of the SHFM and EEC congenital malformations.

    Science.gov (United States)

    Restelli, Michela; Lopardo, Teresa; Lo Iacono, Nadia; Garaffo, Giulia; Conte, Daniele; Rustighi, Alessandra; Napoli, Marco; Del Sal, Giannino; Perez-Morga, David; Costanzo, Antonio; Merlo, Giorgio Roberto; Guerrini, Luisa

    2014-07-15

    Ectrodactyly, or Split-Hand/Foot Malformation (SHFM), is a congenital condition characterized by the loss of central rays of hands and feet. The p63 and the DLX5;DLX6 transcription factors, expressed in the embryonic limb buds and ectoderm, are disease genes for these conditions. Mutations of p63 also cause the ectodermal dysplasia-ectrodactyly-cleft lip/palate (EEC) syndrome, comprising SHFM. Ectrodactyly is linked to defects of the apical ectodermal ridge (AER) of the developing limb buds. FGF8 is the key signaling molecule in this process, able to direct proximo-distal growth and patterning of the skeletal primordial of the limbs. In the limb buds of both p63 and Dlx5;Dlx6 murine models of SHFM, the AER is poorly stratified and FGF8 expression is severely reduced. We show here that the FGF8 locus is a downstream target of DLX5 and that FGF8 counteracts Pin1-ΔNp63α interaction. In vivo, lack of Pin1 leads to accumulation of the p63 protein in the embryonic limbs and ectoderm. We show also that ΔNp63α protein stability is negatively regulated by the interaction with the prolyl-isomerase Pin1, via proteasome-mediated degradation; p63 mutant proteins associated with SHFM or EEC syndromes are resistant to Pin1 action. Thus, DLX5, p63, Pin1 and FGF8 participate to the same time- and location-restricted regulatory loop essential for AER stratification, hence for normal patterning and skeletal morphogenesis of the limb buds. These results shed new light on the molecular mechanisms at the basis of the SHFM and EEC limb malformations. © The Author 2014. Published by Oxford University Press.

  7. Isl1 and Ldb co-regulators of transcription are essential early determinants of mouse limb development

    NARCIS (Netherlands)

    Narkis, G.; Tzchori, I.; Cohen, T.; Holtz, A.; Wier, E.; Westphal, H.

    2012-01-01

    BACKGROUND: The developing limb has served as an excellent model for studying pattern formation and signal transduction in mammalians. Many of the crucial genes that regulate growth and patterning of the limb following limb bud formation are now well known. However, details regarding the control of

  8. SMOC1 Is Essential for Ocular and Limb Development in Humans and Mice

    OpenAIRE

    Okada, Ippei; Hamanoue, Haruka; Terada, Koji; Tohma, Takaya; Megarbane, Andre; Chouery, Eliane; Abou-Ghoch, Joelle; Jalkh, Nadine; Cogulu, Ozgur; Ozkinay, Ferda; Horie, Kyoji; Takeda, Junji; Furuichi, Tatsuya; Ikegawa, Shiro; Nishiyama, Kiyomi

    2011-01-01

    Microphthalmia with limb anomalies (MLA) is a rare autosomal-recessive disorder, presenting with anophthalmia or microphthalmia and hand and/or foot malformation. We mapped the MLA locus to 14q24 and successfully identified three homozygous (one nonsense and two splice site) mutations in the SPARC (secreted protein acidic and rich in cysteine)-related modular calcium binding 1 (SMOC1) in three families. Smoc1 is expressed in the developing optic stalk, ventral optic cup, and limbs of mouse em...

  9. Development of a virtual reality system for the rehabilitation of the upper limb after stroke.

    Science.gov (United States)

    Crosbie, Jacqueline; McDonough, Suzanne; Lennon, Sheila; McNeill, Michael

    2005-01-01

    Virtual reality (VR) provides a three-dimensional computer representation of a real world or imaginary space through which a person can navigate and interact with objects to carry out specific tasks. One novel application of VR technology is in rehabilitation following stroke, particularly of the upper limb. This paper describes the development of a VR system for use in this field. This system gives the user the ability to interact with objects by touching, grasping and moving their upper limb.

  10. Ovarian cycle and embryonic development in Gammarus fossarum: application for reproductive toxicity assessment.

    Science.gov (United States)

    Geffard, Olivier; Xuereb, Benoit; Chaumot, Arnaud; Geffard, Alain; Biagianti, Sylvie; Noël, Claire; Abbaci, Khedidja; Garric, Jeanne; Charmantier, Guy; Charmantier-Daures, Mireille

    2010-10-01

    Among freshwater invertebrates, Gammarus fossarum is an important test organism and is currently used in ecotoxicology for acute and chronic assays; nevertheless, reproductive toxicity test methods are not yet available for these species. In the present study, the reproductive cycle in Gammarus fossarum was characterized in order to propose a reproductive toxicity test encompassing molting, follicle growth, and embryonic development that will provide a better understanding of the mode of action of chemicals disrupting these hormone-regulated processes. A detailed description of the reproductive cycle in Gammarus fossarum was obtained. As in some amphipods, molt and reproductive cycles of G. fossarum females occur concurrently, lasting 30 d at 12°C. Each molt stage is characterized by a specific marsupial embryonic development stage and the size of developing follicles visible on the ovarian membrane. Based on these results, a 21-d reproductive toxicity test is proposed for this species. This new bioassay was applied to identify the specific impact of different stressors: cadmium, methomyl, nonylphenol, and a starvation diet. Good reproducibility was obtained for different endpoints under control conditions and throughout the experiments. Preliminary robust reference values or benchmarks were proposed for these endpoints. Cadmium was found to specially inhibit secondary vitellogenesis. Nonylphenol had a specific concentration-dependent effect on embryonic development, with an increase in the percent abnormality from a concentration of 0.05 µg/L. A restricted food diet led to a significant delay in the molt cycle, which in turn induced inhibition of secondary vitellogenesis. Environ. Toxicol. Chem. 2010;29:2249-2259. © 2010 SETAC.

  11. Micro-magnetic resonance imaging study of live quail embryos during embryonic development.

    Science.gov (United States)

    Duce, Suzanne; Morrison, Fiona; Welten, Monique; Baggott, Glenn; Tickle, Cheryll

    2011-01-01

    Eggs containing live Japanese quail embryos were imaged using micro-magnetic resonance imaging (μMRI) at 24-h intervals from Day 0 to 8, the period during which the main body axis is being laid down and organogenesis is taking place. Considerable detail of non-embryonic structures such as the latebra was revealed at early stages but the embryo could only be visualized around Day 3. Three-dimensional (3D) changes in embryo length and volume were quantified and also changes in volume in the extra- and non-embryonic components. The embryo increased in length by 43% and nearly trebled in volume between Day 4 and Day 5. Although the amount of yolk remained fairly constant over the first 5 days, the amount of albumen decreases significantly and was replaced by extra-embryonic fluid (EEF). ¹H longitudinal (T₁) and transverse (T₂) relaxation times of different regions within the eggs were determined over the first 6 days of development. The T₂ measurements mirrored the changes in image intensity observed, which can be related to the aqueous protein concentrations. In addition, a comparison of the development of Day 0 to 3 quail embryos exposed to radiofrequency (rf) pulses, 7 T static magnetic fields and magnetic field gradients for an average of 7 h with the development of control embryos did not reveal any gross changes, thus confirming that μMRI is a suitable tool for following the development of live avian embryos over time from the earliest stages. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Fe(III Is Essential for Porcine Embryonic Development via Mitochondrial Function Maintenance.

    Directory of Open Access Journals (Sweden)

    Ming-Hui Zhao

    Full Text Available Iron is an important trace element involved in several biological processes. The role of iron in porcine early embryonic development remains unknown. In the present study, we depleted iron (III, Fe3+ with deferoxamine (DFM, a specific Fe3+ chelator, in cultured porcine parthenotes and monitored embryonic development, apoptosis, mitochondrial membrane potential, and ATP production. Results showed biphasic function of Fe3+ in porcine embryo development. 0.5 μM DFM obviously increased blastocyst formation (57.49 ± 2.18% vs. control, 43.99 ± 1.72%, P < 0.05 via reduced (P < 0.05 production of reactive oxygen species (ROS, further increased mitochondrial membrane potential and ATP production in blastocysts (P < 0.05. 0.5 μM DFM decreased mRNA expression of Caspase 3 (Casp3 and increased Bcl-xL. However, results showed a significant reduction in blastocyst formation in the presence of 5.0 μM DFM compared with the control group (DFM, 21.62 ± 3.92% vs. control, 43.99 ± 1.73%, P < 0.05. Fe3+ depletion reduced the total (DFM, 21.10 ± 8.78 vs. control, 44.09 ± 13.65, P < 0.05 and increased apoptotic cell number (DFM, 11.10 ± 5.24 vs. control, 2.64 ± 1.43, P < 0.05 in the blastocyst. An obvious reduction in mitochondrial membrane potential and ATP level after 5.0 μM DFM treatment was observed. Co-localization between mitochondria and cytochrome c was reduced after high concentration of DFM treatment. In conclusion, Fe3+ is essential for porcine embryonic development via mitochondrial function maintenance, but redundant Fe3+ impairs the function of mitochondria.

  13. Ochratoxin A Inhibits Mouse Embryonic Development by Activating a Mitochondrion-Dependent Apoptotic Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Yan-Der Hsuuw

    2013-01-01

    Full Text Available Ochratoxin A (OTA, a mycotoxin found in many foods worldwide, causes nephrotoxicity, hepatotoxicity, and immunotoxicity, both in vitro and in vivo. In the present study, we explored the cytotoxic effects exerted by OTA on the blastocyst stage of mouse embryos, on subsequent embryonic attachment, on outgrowth in vitro, and following in vivo implantation via embryo transfer. Mouse blastocysts were incubated with or without OTA (1, 5, or 10 μM for 24 h. Cell proliferation and growth were investigated using dual differential staining; apoptosis was measured using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL assay; and embryo implantation and post-implantation development were assessed by examination of in vitro growth and the outcome of in vivo embryo transfer, respectively. Blastocysts treated with 10 μM OTA displayed a significantly increased level of apoptosis and a reduction in total cell number. Interestingly, we observed no marked difference in implantation success rate between OTA-pretreated and control blastocysts either during in vitro embryonic development (following implantation in a fibronectin-coated culture dish or after in vivo embryo transfer. However, in vitro treatment with 10 μM OTA was associated with increased resorption of post-implantation embryos by the mouse uterus, and decreased fetal weight upon embryo transfer. Our results collectively indicate that in vitro exposure to OTA triggers apoptosis and retards early post-implantation development after transfer of embryos to host mice. In addition, OTA induces apoptosis-mediated injury of mouse blastocysts, via reactive oxygen species (ROS generation, and promotes mitochondrion-dependent apoptotic signaling processes that impair subsequent embryonic development.

  14. Strain-induced tissue growth laws: applications to embryonic cardiovascular development.

    Science.gov (United States)

    Rugonyi, Sandra

    2013-02-28

    Hemodynamic conditions play an essential role in the cardiovascular system, with abnormal blood flow conditions leading to growth and remodeling of cardiovascular walls. During embryonic development, altered hemodynamic conditions lead to congenital heart disease, which affects about 1% of newborn babies in developed countries. However, the mechanisms by which hemodynamic conditions affect cardiovascular development have not been fully elucidated. In this paper, we propose a model of cardiac growth in response to hemodynamic conditions, in which growth is modulated by a combination of wall strains and wall shear stresses. This is in contrast to previous models that proposed stress-induced growth laws. Because during embryonic development blood pressure increases over time, and this increase in blood pressure produces an increase in wall stresses, stress-induced growth laws would require time-dependent parameters. While blood pressure increases during development, cardiovascular walls become stiffer and thicker, and thus we postulate that instead strains experienced by cells remain approximately the same during development. This assumption motivated our cardioavascular model of strain-induced growth in response to hemodynamic conditions, which we implemented using finite element methods. Model simulations show that the proposed model results in tissue growth that is physiologically reasonable. Further, our analyses demonstrate that mechanical coupling - that results from residual stresses originating from differential tissue growth - may play a more important role in the modulation of cardiovascular tissue growth and remodeling than currently acknowledged.

  15. Effect of the inclination of support in cervical and upper limb development

    Directory of Open Access Journals (Sweden)

    Ailime Perito Feiber Heck

    Full Text Available Introduction It is expected that a child will acquire control of posture (CP of the head and upper limbs in a gradual, sequential and organized way. However, there is still no consensus regarding the best position to achieve this; the evidence suggests that it is prone. Objective To investigate whether age and inclination of the supporting surface in the prone position influence the alignment of the head and upper limbs of children with typical motor development (TMD and atypical motor development (AMD. Methods The study included 29 children aged between one and three months divided according to the Alberta Infant Motor Scale (AIMS into groups with TMD (n = 18 and AMD (n = 11. The children were placed in the prone position with three angles of the support surface (0°, 25° and 45°. Kinematic analysis was conducted to evaluate the alignment angles of the head and upper limbs. Results Children with TMD had higher head alignment. There was no difference in the upper limbs’ alignment between the group with TMD and the group with AMD. In the third month of age compared with the first, increased head alignment and decreased upper limb alignment were found in both groups. The inclination of the supporting surface did not influence the alignment of the head and upper limbs. Conclusions Among the positions evaluated, the prone position without inclination of the supporting surface was more appropriate for weight discharge in the upper limbs, favoring the development of postural control of the child.

  16. Expression pattern of zebrafish rxfp2 homologue genes during embryonic development.

    Science.gov (United States)

    Donizetti, Aldo; Fiengo, Marcella; Del Gaudio, Rosanna; Iazzetti, Giovanni; Pariante, Paolo; Minucci, Sergio; Aniello, Francesco

    2015-11-01

    RXFP2 is one of the 4 receptors for relaxin insulin-like peptides, in particular it binds with high affinity the INSL3 peptide. INSL3/RXFP2 pair is essential for testicular descent during placental mammalian development. The evolutionary history of this ligand/receptor pair has received much attention, since its function in vertebrate species lacking testicular descent, such as the fishes, remains elusive. Herein, we analyzed the expression pattern of three rxfp2 homologue genes in zebrafish embryonic development. For all the three rxfp2 genes (rxfp2a, rxfp2b, and rxfp2-like) we showed the presence of maternally derived transcripts. Later in the development, rxfp2a is only expressed at larval stage, whereas rxfp2b is expressed in all the analyzed stage with highest level in the larvae. The rxfp2-like gene is expressed in all the analyzed stage with a transcript level that increased starting at early pharyngula stage. The spatial localization analysis of rxfp2-like gene showed that it is expressed in many cell clusters in the developing brain. In addition, other rxfp2-like-expressing cells were identified in the retina and oral epithelium. This analysis provides new insights to elucidate the evolution of rxfp2 genes in vertebrate lineage and lays the foundations to study their role in vertebrate embryonic development. © 2015 Wiley Periodicals, Inc.

  17. Semaphorin-1a is required for Aedes aegypti embryonic nerve cord development.

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    Morgan Haugen

    Full Text Available Although mosquito genome projects have uncovered orthologues of many known developmental regulatory genes, extremely little is known about mosquito development. In this study, the role of semaphorin-1a (sema1a was investigated during vector mosquito embryonic ventral nerve cord development. Expression of sema1a and the plexin A (plexA receptor are detected in the embryonic ventral nerve cords of Aedes aegypti (dengue vector and Anopheles gambiae (malaria vector, suggesting that Sema1a signaling may regulate mosquito nervous system development. Analysis of sema1a function was investigated through siRNA-mediated knockdown in A. aegypti embryos. Knockdown of sema1a during A. aegypti development results in a number of nerve cord phenotypes, including thinning, breakage, and occasional fusion of the longitudinal connectives, thin or absent commissures, and general distortion of the nerve cord. Although analysis of Drosophila melanogaster sema1a loss-of-function mutants uncovered many similar phenotypes, aspects of the longitudinal phenotypes differed between D. melanogaster and A. aegypti. The results of this investigation suggest that Sema1a is required for development of the insect ventral nerve cord, but that the developmental roles of this guidance molecule have diverged in dipteran insects.

  18. The human placenta is a hematopoietic organ during the embryonic and fetal periods of development

    OpenAIRE

    Bárcena, Alicia; Kapidzic, Mirhan; Muench, Marcus O.; Gormley, Matthew; Scott, Marvin A.; Weier, Jingly F.; Ferlatte, Christy; Fisher, Susan J.

    2008-01-01

    We studied the potential role of the human placenta as a hematopoietic organ during embryonic and fetal development. Placental samples contained two cell populations—CD34++CD45low and CD34+CD45low—that were found in chorionic villi and in the chorioamniotic membrane. CD34++CD45low cells express many cell surface antigens found on multipotent primitive hematopoietic progenitors and hematopoietic stem cells. CD34++CD45low cells contained colony-forming units culture (CFU-C) with myeloid and ery...

  19. Preliminary observations on the effects of selenate on the development of the embryonic skate, Raja eglanteria

    Science.gov (United States)

    Conrad, G. W.; Luer, C. A.; Paulsen, A. Q.; Funderburgh, J. L.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    Morphogenesis of the clearnose skate, Raja eglanteria, was not significantly inhibited as a result of 7 days of exposure to 1-2 mM selenate in the sea water during Days 59-69 of embryonic development (hatching would normally have occurred at 82 +/- 4 days of incubation). Although corneal transparency appeared normal in the eye, preliminary measurements of the thickness of Bowman's layer of the cornea suggested that it was significantly thinner in the corneas of embryos exposed to 1-2 mM selenate. Selenate is an ion reported to inhibit sulfation of glycosaminoglycans in connective tissue.

  20. Light impacts embryonic and early larval development of the European eel, Anguilla anguilla

    DEFF Research Database (Denmark)

    Politis, Sebastian Nikitas; Butts, Ian; Tomkiewicz, Jonna

    2014-01-01

    stages. In particular, for the 12:12 h photoperiod, embryonic survival, until 26 h post-fertilization was significantly higher when reared under low (62 ± 13%) than those reared under high intensity light (42 ± 13%). Furthermore, embryos reared in low light had a higher hatch success (16 ± 7%) than those...... in the 24:0 h light/dark photoperiod (13 ± 8%), and larvae reared in red light (22 ± 8%) had higher survival than those reared in green (14 ± 8%) or white light (11 ± 8%). Under continuous darkness, development and survival of offspring was as high as the best intensity-photoperiod-spectral composition...

  1. Rhein Induces Oxidative Stress and Apoptosis in Mouse Blastocysts and Has Immunotoxic Effects during Embryonic Development

    Directory of Open Access Journals (Sweden)

    Chien-Hsun Huang

    2017-09-01

    Full Text Available Rhein, a glucoside chemical compound found in a traditional Chinese medicine derived from the roots of rhubarb, induces cell apoptosis and is considered to have high potential as an antitumor drug. Several previous studies showed that rhein can inhibit cell proliferation and trigger mitochondria-related or endoplasmic reticulum (ER stress-dependent apoptotic processes. However, the side effects of rhein on pre- and post-implantation embryonic development remain unclear. Here, we show that rhein has cytotoxic effects on blastocyst-stage mouse embryos and induces oxidative stress and immunotoxicity in mouse fetuses. Blastocysts incubated with 5–20 μM rhein showed significant cell apoptosis, as well as decreases in their inner cell mass cell numbers and total cell numbers. An in vitro development assay showed that rhein affected the developmental potentials of both pre- and post-implantation embryos. Incubation of blastocysts with 5–20 μM rhein was associated with increased resorption of post-implantation embryos and decreased fetal weight in an embryo transfer assay. Importantly, in an in vivo model, intravenous injection of dams with rhein (1, 3, and 5 mg/kg body weight/day for four days resulted in apoptosis of blastocyst-stage embryos, early embryonic developmental injury, and decreased fetal weight. Intravenous injection of dams with 5 mg/kg body weight/day rhein significantly increased the total reactive oxygen species (ROS content of fetuses and the transcription levels of antioxidant proteins in fetal livers. Additional work showed that rhein induced apoptosis through ROS generation, and that prevention of apoptotic processes effectively rescued the rhein-induced injury effects on embryonic development. Finally, the transcription levels of the innate-immunity related genes, CXCL1, IL-1 β and IL-8, were down-regulated in the fetuses of dams that received intravenous injections of rhein. These results collectively show that rhein has

  2. Ofd1 controls dorso-ventral patterning and axoneme elongation during embryonic brain development.

    Directory of Open Access Journals (Sweden)

    Anna D'Angelo

    Full Text Available Oral-facial-digital type I syndrome (OFDI is a human X-linked dominant-male-lethal developmental disorder caused by mutations in the OFD1 gene. Similar to other inherited disorders associated to ciliary dysfunction OFD type I patients display neurological abnormalities. We characterized the neuronal phenotype that results from Ofd1 inactivation in early phases of mouse embryonic development and at post-natal stages. We determined that Ofd1 plays a crucial role in forebrain development, and in particular, in the control of dorso-ventral patterning and early corticogenesis. We observed abnormal activation of Sonic hedgehog (Shh, a major pathway modulating brain development. Ultrastructural studies demonstrated that early Ofd1 inactivation results in the absence of ciliary axonemes despite the presence of mature basal bodies that are correctly orientated and docked. Ofd1 inducible-mediated inactivation at birth does not affect ciliogenesis in the cortex, suggesting a developmental stage-dependent role for a basal body protein in ciliogenesis. Moreover, we showed defects in cytoskeletal organization and apical-basal polarity in Ofd1 mutant embryos, most likely due to lack of ciliary axonemes. Thus, the present study identifies Ofd1 as a developmental disease gene that is critical for forebrain development and ciliogenesis in embryonic life, and indicates that Ofd1 functions after docking and before elaboration of the axoneme in vivo.

  3. Identification and Characterization of Long Non-Coding RNAs Related to Mouse Embryonic Brain Development from Available Transcriptomic Data

    Science.gov (United States)

    He, Hongjuan; Xiu, Youcheng; Guo, Jing; Liu, Hui; Liu, Qi; Zeng, Tiebo; Chen, Yan; Zhang, Yan; Wu, Qiong

    2013-01-01

    Long non-coding RNAs (lncRNAs) as a key group of non-coding RNAs have gained widely attention. Though lncRNAs have been functionally annotated and systematic explored in higher mammals, few are under systematical identification and annotation. Owing to the expression specificity, known lncRNAs expressed in embryonic brain tissues remain still limited. Considering a large number of lncRNAs are only transcribed in brain tissues, studies of lncRNAs in developmental brain are therefore of special interest. Here, publicly available RNA-sequencing (RNA-seq) data in embryonic brain are integrated to identify thousands of embryonic brain lncRNAs by a customized pipeline. A significant proportion of novel transcripts have not been annotated by available genomic resources. The putative embryonic brain lncRNAs are shorter in length, less spliced and show less conservation than known genes. The expression of putative lncRNAs is in one tenth on average of known coding genes, while comparable with known lncRNAs. From chromatin data, putative embryonic brain lncRNAs are associated with active chromatin marks, comparable with known lncRNAs. Embryonic brain expressed lncRNAs are also indicated to have expression though not evident in adult brain. Gene Ontology analysis of putative embryonic brain lncRNAs suggests that they are associated with brain development. The putative lncRNAs are shown to be related to possible cis-regulatory roles in imprinting even themselves are deemed to be imprinted lncRNAs. Re-analysis of one knockdown data suggests that four regulators are associated with lncRNAs. Taken together, the identification and systematic analysis of putative lncRNAs would provide novel insights into uncharacterized mouse non-coding regions and the relationships with mammalian embryonic brain development. PMID:23967161

  4. A novel approach for studying the temporal modulation of embryonic skeletal development using organotypic bone cultures and microcomputed tomography.

    Science.gov (United States)

    Kanczler, Janos M; Smith, Emma L; Roberts, Carol A; Oreffo, Richard O C

    2012-10-01

    Understanding the structural development of embryonic bone in a three dimensional framework is fundamental to developing new strategies for the recapitulation of bone tissue in latter life. We present an innovative combined approach of an organotypic embryonic femur culture model, microcomputed tomography (μCT) and immunohistochemistry to examine the development and modulation of the three dimensional structures of the developing embryonic femur. Isolated embryonic chick femurs were organotypic (air/liquid interface) cultured for 10 days in either basal, chondrogenic, or osteogenic supplemented culture conditions. The growth development and modulating effects of basal, chondrogenic, or osteogenic culture media of the embryonic chick femurs was investigated using μCT, immunohistochemistry, and histology. The growth and development of noncultured embryonic chick femur stages E10, E11, E12, E13, E15, and E17 were very closely correlated with increased morphometric indices of bone formation as determined by μCT. After 10 days in the organotpyic culture set up, the early aged femurs (E10 and E11) demonstrated a dramatic response to the chondrogenic or osteogenic culture conditions compared to the basal cultured femurs as determined by a change in μCT morphometric indices and modified expression of chondrogenic and osteogenic markers. Although the later aged femurs (E12 and E13) increased in size and structure after 10 days organotpypic culture, the effects of the osteogenic and chondrogenic organotypic cultures on these femurs were not significantly altered compared to basal conditions. We have demonstrated that the embryonic chick femur organotpyic culture model combined with the μCT and immunohistochemical analysis can provide an integral methodology for investigating the modulation of bone development in an ex vivo culture setting. Hence, these interdisciplinary techniques of μCT and whole organ bone cultures will enable us to delineate some of the temporal

  5. Functional analysis of limb transcriptional enhancers in the mouse.

    Science.gov (United States)

    Nolte, Mark J; Wang, Ying; Deng, Jian Min; Swinton, Paul G; Wei, Caimiao; Guindani, Michele; Schwartz, Robert J; Behringer, Richard R

    2014-01-01

    Transcriptional enhancers are genomic sequences bound by transcription factors that act together with basal transcriptional machinery to regulate gene transcription. Several high-throughput methods have generated large datasets of tissue-specific enhancer sequences with putative roles in developmental processes. However, few enhancers have been deleted from the genome to determine their roles in development. To understand the roles of two enhancers active in the mouse embryonic limb bud we deleted them from the genome. Although the genes regulated by these enhancers are unknown, they were selected because they were identified in a screen for putative limb bud-specific enhancers associated with p300, an acetyltransferase that participates in protein complexes that promote active transcription, and because the orthologous human enhancers (H1442 and H280) drive distinct lacZ expression patterns in limb buds of embryonic day (E) 11.5 transgenic mice. We show that the orthologous mouse sequences, M1442 and M280, regulate dynamic expression in the developing limb. Although significant transcriptional differences in enhancer-proximal genes in embryonic limb buds accompany the deletion of M1442 and M280 no gross limb malformations during embryonic development were observed, demonstrating that M1442 and M280 are not required for mouse limb development. However, M280 is required for the development and/or maintenance of body size; M280 mice are significantly smaller than controls. M280 also harbors an "ultraconserved" sequence that is identical between human, rat, and mouse. This is the first report of a phenotype resulting from the deletion of an ultraconserved element. These studies highlight the importance of determining enhancer regulatory function by experiments that manipulate them in situ and suggest that some of an enhancer's regulatory capacities may be developmentally tolerated rather than developmentally required. © 2014 Wiley Periodicals, Inc.

  6. Proximate effects of temperature versus evolved intrinsic constraints for embryonic development times among temperate and tropical songbirds

    Science.gov (United States)

    Ton, Riccardo; Martin, Thomas E.

    2017-01-01

    The relative importance of intrinsic constraints imposed by evolved physiological trade-offs versus the proximate effects of temperature for interspecific variation in embryonic development time remains unclear. Understanding this distinction is important because slow development due to evolved trade-offs can yield phenotypic benefits, whereas slow development from low temperature can yield costs. We experimentally increased embryonic temperature in free-living tropical and north temperate songbird species to test these alternatives. Warmer temperatures consistently shortened development time without costs to embryo mass or metabolism. However, proximate effects of temperature played an increasingly stronger role than intrinsic constraints for development time among species with colder natural incubation temperatures. Long development times of tropical birds have been thought to primarily reflect evolved physiological trade-offs that facilitate their greater longevity. In contrast, our results indicate a much stronger role of temperature in embryonic development time than currently thought.

  7. On the Formation of Digits and Joints during Limb Development.

    Science.gov (United States)

    Hiscock, Tom W; Tschopp, Patrick; Tabin, Clifford J

    2017-06-05

    Critical steps in forming the vertebrate limb include the positioning of digits and the positioning of joints within each digit. Recent studies have proposed that the iterative series of digits is established by a Turing-like mechanism generating stripes of chondrogenic domains. However, re-examination of available data suggest that digits are actually patterned as evenly spaced spots, not stripes, which then elongate into rod-shaped digit rays by incorporating new cells at their tips. Moreover, extension of the digit rays and the patterning of the joints occur simultaneously at the distal tip, implying that an integrated model is required to fully understand these processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Characterization of the onset of embryonic control and early development in the bovine embryo

    International Nuclear Information System (INIS)

    Barnes, F.L.

    1988-01-01

    Bovine embryos were used to determine if morphological and molecular features of early development are similar to in vivo recovered bovine embryos and to determine at what level early bovine development is regulated. Radiolabeling of IVP embryos and in vivo recovered embryos with 35 S-methionine for SDS-polyacrylamide gel electrophoresis reveals that these embryos are equivalent. Few differences in protein profiles are observed between 1- and early 4-cell embryos. A change in protein profiles begins at the mid 4-cell stage and continues into the 8-cell stage. Few differences in protein profiles are observed between 1- and early 4-cell embryos. A change in protein profiles begins at the mid 4-cell stage and continues into the 8-cell stage. Few differences in protein profiles are observed between late 8-cells and morulae. This transition is α-amanitin sensitive therefore due to de novo embryonic transcription. Embryonic transcription is partially responsible for terminating the post-transcriptionally regulated period of early bovine development. Argentophillic nucleolar organizing regions (Ag-NORs) indicate onset of nucleolar activation. Ag-NORs were absent in 2- and 4-cell IVP embryos and rarely occurred in 8-cell IVP embryos cultured in vitro. IVP 1- and 2-cell embryos cultured to blastocysts in sheep oviducts demonstrated Ag-NORs. Thus the lack of nucleolar activation of IVP embryos cultured in vitro is culture induced between the 2- and 8-cell stage

  9. Melatonin prevents postovulatory oocyte aging and promotes subsequent embryonic development in the pig.

    Science.gov (United States)

    Wang, Tao; Gao, Ying-Ying; Chen, Li; Nie, Zheng-Wen; Cheng, Wei; Liu, Xiaoyan; Schatten, Heide; Zhang, Xia; Miao, Yi-Liang

    2017-06-26

    Oxidative stress is known as a major contributing factor involved in oocyte aging, which negatively affects oocyte quality and development after fertilization. Melatonin is an effective free radical scavenger and its metabolites AFMK and AMK are powerful detoxifiers that eliminate free radicals. In this study, we used porcine oocytes to test the hypothesis that melatonin could scavenge free radicals produced during oocyte aging, thereby maintaining oocyte quality. We compared reactive oxygen species levels, apoptosis levels, mitochondrial membrane potential ratios, total glutathione contents and expression levels in fresh, aged and melatonin-treated aged porcine oocytes and observed the percentage of blastocyst formation following parthenogenetic activation. We found that melatonin could effectively maintain the morphology of oocytes observed in control oocytes, alleviate oxidative stress, markedly decrease early apoptosis levels, retard the decline of mitochondrial membrane potential and significantly promote subsequent embryonic development in oocytes aged for 24 hr in vitro . These results strongly suggest that melatonin can prevent postovulatory oocyte aging and promote subsequent embryonic development in the pig, which might find practical applications to control oocyte aging in other mammalian species including humans to maintain the quality of human oocytes when performing clinical assisted reproductive technology.

  10. Embryonic development and inviability phenotype of chicken-Japanese quail F1 hybrids

    Science.gov (United States)

    Ishishita, Satoshi; Kinoshita, Keiji; Nakano, Mikiharu; Matsuda, Yoichi

    2016-01-01

    Interspecific hybrid incompatibility, including inviability and sterility, is important in speciation; however, its genetic basis remains largely unknown in vertebrates. Crosses between male chickens and female Japanese quails using artificial insemination can generate intergeneric hybrids; however, the hatching rate is low, and hatched hybrids are only sterile males. Hybrid development is arrested frequently during the early embryonic stages, and the sex ratio of living embryos is male-biased. However, the development and sex ratio of hybrid embryos have not been comprehensively analyzed. In the present study, we observed delayed embryonic development of chicken-quail hybrids during the early stage, compared with that of chickens and quails. The survival rate of hybrids decreased markedly during the blastoderm-to-pre-circulation stage and then decreased gradually through the subsequent stages. Hybrid females were observed at more than 10 d of incubation; however, the sex ratio of hybrids became male-biased from 10 d of incubation. Severely malformed embryos were observed frequently in hybrids. These results suggest that developmental arrest occurs at various stages in hybrid embryos, including a sexually non-biased arrest during the early stage and a female-biased arrest during the late stage. We discuss the genetic basis for hybrid inviability and its sex bias. PMID:27199007

  11. [Effects of temperature on the embryonic development and larval growth of Sepia lycidas].

    Science.gov (United States)

    Jiang, Xia-Min; Peng, Rui-Bing; Luo, Jiang; Tang, Feng

    2013-05-01

    A single-factor experiment was conducted to study the effects of different temperature (15, 18, 21, 24, 27, 30, and 33 degrees C) on the embryonic development and larval growth of Sepia lycidas, aimed to search for the optimum temperature for the development and growth of S. lycidas. The results showed that temperature had significant effects on the embryonic development and larval growth of S. lycidas (P < 0.05). The suitable temperature for hatching ranged from 21 degrees C to 30 degrees C, and the optimum temperature was 24 degrees C. At the optimum temperature, the hatching rate was (93.3 +/- 2.9)%, incubation period was (24.33 +/- 0.58) d, hatching period was (6.00 +/- 1.00) d, completely absorked rate of yolk sac was (96.4 +/- 3.1)%, and newly hatched larvae mass was (0.258 +/- 0.007) g. The effective accumulated temperature model was N = 284.42/(T-12.57). The suitable temperature for the larval survival and growth ranged from 21 degrees C to 30 degrees C, and the optimum temperature was from 24 degrees C to 27 degrees C. At the optimum temperature, the survival rate ranged from 70.0% to 73.3%, and the specific growth rate was from 2.4% to 3.8%.

  12. Nitrogen excretion during embryonic development of the green iguana, Iguana iguana (Reptilia; Squamata).

    Science.gov (United States)

    Sartori, M R; Taylor, E W; Abe, A S

    2012-10-01

    Development within the cleidoic egg of birds and reptiles presents the embryo with the problem of accumulation of wastes from nitrogen metabolism. Ammonia derived from protein catabolism is converted into the less toxic product urea or relatively insoluble uric acid. The pattern of nitrogen excretion of the green iguana, Iguana iguana, was determined during embryonic development using samples from allantoic fluid and from the whole homogenized egg, and in hatchlings and adults using samples of blood plasma. Urea was the major excretory product over the course of embryonic development. It was found in higher concentrations in the allantoic sac, suggesting that there is a mechanism present on the allantoic membrane enabling the concentration of urea. The newly hatched iguana still produced urea while adults produced uric acid. The time course of this shift in the type of nitrogen waste was not determined but the change is likely to be related to the water relations associated with the terrestrial habit of the adult. The green iguana produces parchment-shelled eggs that double in mass during incubation due to water absorption; the eggs also accumulate 0.02 mM of urea, representing 82% of the total measured nitrogenous residues that accumulate inside the allantois. The increase in egg mass and urea concentration became significant after 55 days of incubation then were unchanged until hatching. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. dif-1 and colt, both implicated in early embryonic development, encode carnitine acylcarnitine translocase.

    Science.gov (United States)

    Oey, Nadia A; Ijlst, Lodewijk; van Roermund, Carlo W T; Wijburg, Frits A; Wanders, Ronald J A

    2005-06-01

    It has always been assumed that during development the embryo and fetus depend only on glycolysis for energy generation and that they do not oxidize fatty acids. Recently, however, we found abundant expression and activity of fatty acid oxidation (FAO) enzymes in the human embryo and fetus. In a search for FAO gene expression during development we came across two embryonic differentiation genes: differentiation defective (dif-1) and congested-like trachea (colt) of Caenorhabditis elegans and Drosophila melanogaster, respectively. Earlier studies showed that expression of these two genes is essential during developmental stages with high energy requirements. Both dif-1 and colt encode proteins with sequence similarity to the mitochondrial carnitine acylcarnitine carrier (CACT), which suggests that the DIF-1 and COLT proteins might be functional orthologues of CACT. To investigate this, we expressed both dif-1 and colt in Saccharomyces cerevisiae. Our results show that DIF-1 and COLT can functionally complement a yeast CACT deletion strain and thus function as carnitine acylcarnitine transporters. This finding is well in line with the recent observation that embryos are capable of oxidizing fatty acids and furthermore implies that FAO is essential during early embryonic development when the energy demand is high.

  14. UTX and UTY demonstrate histone demethylase-independent function in mouse embryonic development.

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    Karl B Shpargel

    2012-09-01

    Full Text Available UTX (KDM6A and UTY are homologous X and Y chromosome members of the Histone H3 Lysine 27 (H3K27 demethylase gene family. UTX can demethylate H3K27; however, in vitro assays suggest that human UTY has lost enzymatic activity due to sequence divergence. We produced mouse mutations in both Utx and Uty. Homozygous Utx mutant female embryos are mid-gestational lethal with defects in neural tube, yolk sac, and cardiac development. We demonstrate that mouse UTY is devoid of in vivo demethylase activity, so hemizygous X(Utx- Y(+ mutant male embryos should phenocopy homozygous X(Utx- X(Utx- females. However, X(Utx- Y(+ mutant male embryos develop to term; although runted, approximately 25% survive postnatally reaching adulthood. Hemizygous X(+ Y(Uty- mutant males are viable. In contrast, compound hemizygous X(Utx- Y(Uty- males phenocopy homozygous X(Utx- X(Utx- females. Therefore, despite divergence of UTX and UTY in catalyzing H3K27 demethylation, they maintain functional redundancy during embryonic development. Our data suggest that UTX and UTY are able to regulate gene activity through demethylase independent mechanisms. We conclude that UTX H3K27 demethylation is non-essential for embryonic viability.

  15. Development of pacemaker properties and rhythmogenic mechanisms in the mouse embryonic respiratory network

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    Chevalier, Marc; Toporikova, Natalia; Simmers, John; Thoby-Brisson, Muriel

    2016-01-01

    Breathing is a vital rhythmic behavior generated by hindbrain neuronal circuitry, including the preBötzinger complex network (preBötC) that controls inspiration. The emergence of preBötC network activity during prenatal development has been described, but little is known regarding inspiratory neurons expressing pacemaker properties at embryonic stages. Here, we combined calcium imaging and electrophysiological recordings in mouse embryo brainstem slices together with computational modeling to reveal the existence of heterogeneous pacemaker oscillatory properties relying on distinct combinations of burst-generating INaP and ICAN conductances. The respective proportion of the different inspiratory pacemaker subtypes changes during prenatal development. Concomitantly, network rhythmogenesis switches from a purely INaP/ICAN-dependent mechanism at E16.5 to a combined pacemaker/network-driven process at E18.5. Our results provide the first description of pacemaker bursting properties in embryonic preBötC neurons and indicate that network rhythmogenesis undergoes important changes during prenatal development through alterations in both circuit properties and the biophysical characteristics of pacemaker neurons. DOI: http://dx.doi.org/10.7554/eLife.16125.001 PMID:27434668

  16. Differential gene expression patterns during embryonic development of sea urchin exposed to triclosan.

    Science.gov (United States)

    Hwang, Jinik; Suh, Sung-Suk; Park, Mirye; Park, So Yun; Lee, Sukchan; Lee, Taek-Kyun

    2017-02-01

    Triclosan (TCS; 2,4,4'-trichloro-2'-hydroxydiphenyl ether) is a broad-spectrum antibacterial agent used in common industrial, personal care and household products which are eventually rinsed down the drain and discharged with wastewater effluent. It is therefore commonly found in the aquatic environment, leading to the continual exposure of aquatic organisms to TCS and the accumulation of the antimicrobial and its harmful degradation products in their bodies. Toxic effects of TCS on reproductive and developmental progression of some aquatic organisms have been suggested but the underlying molecular mechanisms have not been defined. We investigated the expression patterns of genes involved in the early development of TCS-treated sea urchin Strongylocentrotus nudus using cDNA microarrays. We observed that the predominant consequence of TCS treatment in this model system was the widespread repression of TCS-modulated genes. In particular, empty spiracles homeobox 1 (EMX-1), bone morphogenic protein, and chromosomal binding protein genes showed a significant decrease in expression in response to TCS. These results suggest that TCS can induce abnormal development of sea urchin embryos through the concomitant suppression of a number of genes that are necessary for embryonic differentiation in the blastula stage. Our data provide new insight into the crucial role of genes associated with embryonic development in response to TCS. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 426-433, 2017. © 2016 Wiley Periodicals, Inc.

  17. Redundant role of protein kinase C delta and epsilon during mouse embryonic development.

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    Sergio Carracedo

    Full Text Available Protein Kinase C delta and epsilon are mediators of important cellular events, such as cell proliferation, migration or apoptosis. The formation of blood vessels, i.e., vasculo- and angiogenesis, is a process where these isoforms have also been shown to participate. However, mice deficient in either Protein Kinase C delta or epsilon are viable and therefore their individual contribution to the formation of the vasculature appeared so far dispensable. In this study, we show that double null mutation of Protein Kinase C delta and epsilon causes embryonic lethality at approximately E9.5. At this stage, whole mount staining of the endothelial marker CD31 in double null embryos revealed defective blood vessel formation. Moreover, culture of double deficient mouse allantois showed impaired endothelial cell organization, and analyses of double deficient embryo sections showed dilated vessels, decreased endothelial-specific adherent junctions, and decreased contact of endothelial cells with mural cells. Protein kinase C delta and epsilon also appeared essential for vascular smooth muscle cell differentiation, since α-smooth muscle actin, a classical marker for vascular smooth muscle cells, was almost undetectable in double deficient embryonic aorta at E9.5. Subsequent qPCR analyses showed decreased VE-cadherin, Vegfr2, Cd31, Cdh2, Ets1, and Fli-1, among other angiogenesis related transcripts in double deficient embryos. Taken together, these data suggest for the first time an in vivo redundant role between members of the novel Protein Kinase C subfamily that allows for mutual compensation during mouse embryonic development, with vasculogenesis/angiogenesis as an obvious common function of these two Protein Kinase Cs. Protein Kinase C delta and epsilon might therefore be useful targets for inhibiting vasculo- and/or angiogenesis.

  18. G-quadruplexes as novel cis-elements controlling transcription during embryonic development.

    Science.gov (United States)

    David, Aldana P; Margarit, Ezequiel; Domizi, Pablo; Banchio, Claudia; Armas, Pablo; Calcaterra, Nora B

    2016-05-19

    G-quadruplexes are dynamic structures folded in G-rich single-stranded DNA regions. These structures have been recognized as a potential nucleic acid based mechanism for regulating multiple cellular processes such as replication, transcription and genomic maintenance. So far, their transcriptional role in vivo during vertebrate embryonic development has not yet been addressed. Here, we performed an in silico search to find conserved putative G-quadruplex sequences (PQSs) within proximal promoter regions of human, mouse and zebrafish developmental genes. Among the PQSs able to fold in vitro as G-quadruplex, those present in nog3, col2a1 and fzd5 promoters were selected for further studies. In cellulo studies revealed that the selected G-quadruplexes affected the transcription of luciferase controlled by the SV40 nonrelated promoter. G-quadruplex disruption in vivo by microinjection in zebrafish embryos of either small ligands or DNA oligonucleotides complementary to the selected PQSs resulted in lower transcription of the targeted genes. Moreover, zebrafish embryos and larvae phenotypes caused by the presence of complementary oligonucleotides fully resembled those ones reported for nog3, col2a1 and fzd5 morphants. To our knowledge, this is the first work revealing in vivo the role of conserved G-quadruplexes in the embryonic development, one of the most regulated processes of the vertebrates biology. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. Reproductive effects of two neonicotinoid insecticides on mouse sperm function and early embryonic development in vitro.

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    Yi-Hua Gu

    Full Text Available Acetamiprid (ACE and imidacloprid (IMI are two major members in the family of neonicotinoid pesticides, which are synthesized with a higher selectivity to insects. The present study determined and compared in vitro effects of ACE, IMI and nicotine on mammalian reproduction by using an integrated testing strategy for reproductive toxicology, which covered sperm quality, sperm penetration into oocytes and preimplantation embryonic development. Direct chemical exposure (500 µM or 5 mM on spermatozoa during capacitation was performed, and in vitro fertilization (IVF process, zygotes and 2-cell embryos were respectively incubated with chemical-supplemented medium until blastocyst formation to evaluate the reproductive toxicity of these chemicals and monitor the stages mainly affected. Generally, treatment of 500 µM or 5 mM chemicals for 30 min did not change sperm motility and DNA integrity significantly but the fertilization ability in in vitro fertilization (IVF process, indicating that IVF process could detect and distinguish subtle effect of spermatozoa exposed to different chemicals. Culture experiment in the presence of chemicals in medium showed that fertilization process and zygotes are adversely affected by direct exposure of chemicals (PIMI>ACE, whereas developmental progression of 2-cell stage embryos was similar to controls (P>0.05. These findings unveiled the hazardous effects of neonicotinoid pesticides exposure on mammalian sperm fertilization ability as well as embryonic development, raising the concerns that neonicotinoid pesticides may pose reproductive risks on human reproductive health, especially in professional populations.

  20. Dynamic Pattern of HOXB9 Protein Localization during Oocyte Maturation and Early Embryonic Development in Mammals.

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    Caroline Sauvegarde

    Full Text Available We previously showed that the homeodomain transcription factor HOXB9 is expressed in mammalian oocytes and early embryos. However, a systematic and exhaustive study of the localization of the HOXB9 protein, and HOX proteins in general, during mammalian early embryonic development has so far never been performed.The distribution of HOXB9 proteins in oocytes and the early embryo was characterized by immunofluorescence from the immature oocyte stage to the peri-gastrulation period in both the mouse and the bovine. HOXB9 was detected at all studied stages with a dynamic expression pattern. Its distribution was well conserved between the two species until the blastocyst stage and was mainly nuclear. From that stage on, trophoblastic cells always showed a strong nuclear staining, while the inner cell mass and the derived cell lines showed important dynamic variations both in staining intensity and in intra-cellular localization. Indeed, HOXB9 appeared to be progressively downregulated in epiblast cells and only reappeared after gastrulation had well progressed. The protein was also detected in the primitive endoderm and its derivatives with a distinctive presence in apical vacuoles of mouse visceral endoderm cells.Together, these results could suggest the existence of unsuspected functions for HOXB9 during early embryonic development in mammals.

  1. Identification and Expression Analysis of Zebrafish (Danio rerio E-Selectin during Embryonic Development

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    Guijin Sun

    2015-10-01

    Full Text Available In this study, we cloned the full-length cDNA of E-selectin of zebrafish (Danio rerio, analyzed its expression pattern and preliminarily explored its biological function. Zebrafish E-selectin cDNA is 3146 bp and encodes a putative 871 amino acid protein. All structural domains involved in E-selectin function are conserved in the putative protein. Whole-mount in situ hybridization of zebrafish at 24 and 48 h post-fertilization (hpf revealed E-selectin expression mainly in vascular/endothelial progenitor cells in the posterior trunk and blood cells in the intermediate cell mass and posterior cardinal vein regions. Real-time quantitative RT-PCR analysis detected E-selectin expression at 0.2, 24 and 48 hpf and significantly decreased from 48 to 72 hpf. The expression of E-selectin, tumor necrosis factor-α and interleukin-1β was significantly upregulated at 22 to 72 h after induction with bacterial lipopolysaccharide. Thus, the structure of E-selectin protein is highly conserved among species, and E-selectin may be involved in embryonic development and essential for hematopoiesis and angiogenesis during embryonic development in zebrafish. Furthermore, we provide the first evidence of inflammatory mediators inducing E-selectin expression in non-mammalian vertebrates, which suggests that zebrafish E-selectin may be involved in inflammation and probably has similar biological function to mammalian E-selectin.

  2. Embryonic Testicular Regression Syndrome Presenting as Primary Amenorrhea: A Case Report and Review of Disorders of Sexual Development.

    Science.gov (United States)

    Hunter, J D; Pierce, S R; Calikoglu, A S; Howell, J O

    2016-08-01

    Sex development depends on the synchronous interaction of complicated genetic and hormonal events. Sex differentiation begins with sex determination, which is the assignment of the embryonic bipotential gonads as either testes or ovaries on the basis of transcriptional regulation. Hormonal regulation then directs the development of the male or female phenotype. Disruptions of this intricate cascade of events result in disorders of sexual development. A 16-year-old female adolescent presented with primary amenorrhea. Evaluation revealed female external genitalia, XY karyotype, absent gonadal tissue, and rudimentary Müllerian structures. On the basis of her constellation of findings, the most logical diagnosis was the rare embryonic testicular regression syndrome. A careful understanding of embryonic sexual development is critical to the evaluation of patients with disorders of sexual development. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  3. Spatial and temporal expression of CD44 isoforms in the developing and growing joints of the rat limb.

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    Noonan, K J; Reiter, R S; Kurriger, G L; Martin, J A; Maynard, J A; Stevens, J W

    1998-01-01

    Hyaluronan is an integral component of proteoglycan-rich extracellular matrices such as hyaline cartilage. Hyaluronan is commonly found in embryonic tissue and is important in the formation of hydrated matrices that allow cellular expansion and migration. Cell surface hyaluronan-binding proteins such as CD44 are presumed to be important in the cellular interactions with hyaluronan in both of these processes. The primary aim of this study was to document the spatial and temporal expressions of CD44 isoforms during the development and growth of the diarthrodial joints of rat limbs. With use of in situ hybridization and immunohistochemistry, the CD44s isoform is selectively identified as localized to a single cell layer on opposing sides of the joint at the first appearance of joint cavitation (on the 18th day of gestation). After joint formation in the neonate, the expression of the CD44s isoform in the cells at the joint surface is lost. These findings suggest that the CD44s isoform has a role in the development of the diarthrodial joint, presumably through interaction with hyaluronan.

  4. Three-dimensional microCT imaging of murine embryonic development from immediate post-implantation to organogenesis: application for phenotyping analysis of early embryonic lethality in mutant animals.

    Science.gov (United States)

    Ermakova, Olga; Orsini, Tiziana; Gambadoro, Alessia; Chiani, Francesco; Tocchini-Valentini, Glauco P

    2018-04-01

    In this work, we applied three-dimensional microCT imaging to study murine embryogenesis in the range from immediate post-implantation period (embryonic day 5.5) to mid-gestation (embryonic day 12.5) with the resolution up to 1.4 µm/voxel. Also, we introduce an imaging procedure for non-invasive volumetric estimation of an entire litter of embryos within the maternal uterine structures. This method allows for an accurate, detailed and systematic morphometric analysis of both embryonic and extra-embryonic components during embryogenesis. Three-dimensional imaging of unperturbed embryos was performed to visualize the egg cylinder, primitive streak, gastrulation and early organogenesis stages of murine development in the C57Bl6/N mouse reference strain. Further, we applied our microCT imaging protocol to determine the earliest point when embryonic development is arrested in a mouse line with knockout for tRNA splicing endonuclease subunit Tsen54 gene. Our analysis determined that the embryonic development in Tsen54 null embryos does not proceed beyond implantation. We demonstrated that application of microCT imaging to entire litter of non-perturbed embryos greatly facilitate studies to unravel gene function during early embryogenesis and to determine the precise point at which embryonic development is arrested in mutant animals. The described method is inexpensive, does not require lengthy embryos dissection and can be applicable for detailed analysis of mutant mice at laboratory scale as well as for high-throughput projects.

  5. The effect of acute irradiation on the development of limbs in sheep

    International Nuclear Information System (INIS)

    Rajtova, V.; Horak, J.

    1976-01-01

    The effect of acute irradiation on the limb development in sheep was studied. The pelvic area of a pregnant sheep was irradiated locally on the 28th, 29th and 30th days after fertilization. The fetus was removed on the 15th day after irradiation and treated histologically. A single exposure with 250 R (higher exposures killed the fetus) was found to cease the limb development on the 28th day after irradiation (the critical period of the sheep limb development), to induce persistence of the intermedial ray on the 29th and 30th days, an early disappearance of the side finger rays, an early disappearance, fusion or deformation of some carpal and tarsal elements on the 29th and the 30th days after irradiation. (author)

  6. GATA4-dependent organ-specific endothelial differentiation controls liver development and embryonic hematopoiesis.

    Science.gov (United States)

    Géraud, Cyrill; Koch, Philipp-Sebastian; Zierow, Johanna; Klapproth, Kay; Busch, Katrin; Olsavszky, Victor; Leibing, Thomas; Demory, Alexandra; Ulbrich, Friederike; Diett, Miriam; Singh, Sandhya; Sticht, Carsten; Breitkopf-Heinlein, Katja; Richter, Karsten; Karppinen, Sanna-Maria; Pihlajaniemi, Taina; Arnold, Bernd; Rodewald, Hans-Reimer; Augustin, Hellmut G; Schledzewski, Kai; Goerdt, Sergij

    2017-03-01

    Microvascular endothelial cells (ECs) are increasingly recognized as organ-specific gatekeepers of their microenvironment. Microvascular ECs instruct neighboring cells in their organ-specific vascular niches through angiocrine factors, which include secreted growth factors (angiokines), extracellular matrix molecules, and transmembrane proteins. However, the molecular regulators that drive organ-specific microvascular transcriptional programs and thereby regulate angiodiversity are largely elusive. In contrast to other ECs, which form a continuous cell layer, liver sinusoidal ECs (LSECs) constitute discontinuous, permeable microvessels. Here, we have shown that the transcription factor GATA4 controls murine LSEC specification and function. LSEC-restricted deletion of Gata4 caused transformation of discontinuous liver sinusoids into continuous capillaries. Capillarization was characterized by ectopic basement membrane deposition, formation of a continuous EC layer, and increased expression of VE-cadherin. Correspondingly, ectopic expression of GATA4 in cultured continuous ECs mediated the downregulation of continuous EC-associated transcripts and upregulation of LSEC-associated genes. The switch from discontinuous LSECs to continuous ECs during embryogenesis caused liver hypoplasia, fibrosis, and impaired colonization by hematopoietic progenitor cells, resulting in anemia and embryonic lethality. Thus, GATA4 acts as master regulator of hepatic microvascular specification and acquisition of organ-specific vascular competence, which are indispensable for liver development. The data also establish an essential role of the hepatic microvasculature in embryonic hematopoiesis.

  7. Structural requirements for PACSIN/Syndapin operation during zebrafish embryonic notochord development.

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    Melissa A Edeling

    2009-12-01

    Full Text Available PACSIN/Syndapin proteins are membrane-active scaffolds that participate in endocytosis. The structure of the Drosophila Syndapin N-terminal EFC domain reveals a crescent shaped antiparallel dimer with a high affinity for phosphoinositides and a unique membrane-inserting prong upon the concave surface. Combined structural, biochemical and reverse genetic approaches in zebrafish define an important role for Syndapin orthologue, Pacsin3, in the early formation of the notochord during embryonic development. In pacsin3-morphant embryos, midline convergence of notochord precursors is defective as axial mesodermal cells fail to polarize, migrate and differentiate properly. The pacsin3 morphant phenotype of a stunted body axis and contorted trunk is rescued by ectopic expression of Drosophila Syndapin, and depends critically on both the prong that protrudes from the surface of the bowed Syndapin EFC domain and the ability of the antiparallel dimer to bind tightly to phosphoinositides. Our data confirm linkage between directional migration, endocytosis and cell specification during embryonic morphogenesis and highlight a key role for Pacsin3 in this coupling in the notochord.

  8. A scanning electron microscopy study of the embryonic development of Pycnogonum litorale (Arthropoda, Pycnogonida).

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    Machner, Jakob; Scholtz, Gerhard

    2010-11-01

    The phylogenetic position of the enigmatic Pycnogonida (sea spiders) is still controversial. This is in part due to a lack of detailed data about the morphology and ontogenesis of this, in many aspects, aberrant group. In particular, studies on the embryonic development of pycnogonids are rare and in part contradictory. Here, we present the first embryological study of a pycnogonid species using scanning electron microscopy (SEM). We describe the late embryogenesis of Pycnogonum litorale from the first visible appendage anlagen to the hatchling in 11 embryonic stages. The three pairs of appendage anlagen gain in length by growth, as well as by extension of furrows into the embryo. The opening of the stomodaeum is located far in front of the anlagen of the chelifores and has a Y-shaped lumen from the onset. During further embryogenesis, the position of the mouth shifts ventrally, until it is located between the chelifores. The proboscis anlage grows out as a circumoral wall-like structure, which is initially more pronounced ventrally. Hypotheses about the evolution of the proboscis by fusion of originally separated components are critically discussed, because the proboscis anlage of P. litorale shows no indications of a composite nature. In particular, a participation of post-cheliforal elements in proboscis formation is rejected by our data. Further, no preoral structure and no stage in proboscis formation was found, which could plausibly be homologized with the labrum of othereuarthropods. Thus, our study supports the assumption of a complete lack of a labrum in Pycnogonida.

  9. Gene and protein expressions of vimentin and desmin during embryonic development of the mylohyoid muscle.

    Science.gov (United States)

    Kishi, Asuka; Yamamoto, Masahito; Kikuchi, Akihito; Iwanuma, Osamu; Watanabe, Yutaka; Ide, Yoshinobu; Abe, Shinichi

    2012-09-01

    Meckel's cartilage is known to be involved in formation of the prenatal mandible. However, the relationship between Meckel's cartilage and the embryonic mylohyoid muscle during growth and development has been investigated only rarely. This study examined the expression of intermediate filaments in Meckel's cartilage and the embryonic mylohyoid muscle in fetal mice during morphological development. Specimens of E12-16 ICR mice sectioned in the frontal direction were subjected to immunohistochemistry for vimentin and desmin. Hematoxylin and eosin sections showed that the immature mylohyoid muscle began to grow along Meckel's cartilage during fetal development. Weak vimentin expression was detected in the mylohyoid muscle and surrounding tissues at E12. Desmin expression was detected specifically in the mylohyoid, and strong expression was evident after E13, and increased with age. It was inferred that the mylohyoid muscle is one the tissues developing from Meckel's cartilage, the latter exerting a continuous influence on the growth of the former. In the early stage, the surrounding mesenchymal tissues expressing vimentin formed a scaffold for the developing mylohyoid muscle. Muscle attachment at E13 showed steady desmin expression, which continued until maturity. This study suggested the possibility that Meckel's cartilage has an influence not only on the mandibular bone, but also on the development of the mylohyoid muscle attached to the mandibular bone. Furthermore, it revealed a stage of the developmental process of the mylohyoid muscle in which the expression of vimentin, which is a common protein in the surrounding tissue such as muscle and bone, induces the morphological formation of the mylohyoid muscle, cooperating with the surrounding structures.

  10. Student Learning of Early Embryonic Development via the Utilization of Research Resources from the Nematode "Caenorhabditis elegans"

    Science.gov (United States)

    Lu, Fong-Mei; Eliceiri, Kevin W.; Squirrell, Jayne M.; White, John G.; Stewart, James

    2008-01-01

    This study was undertaken to gain insights into undergraduate students' understanding of early embryonic development, specifically, how well they comprehend the concepts of volume constancy, cell lineages, body plan axes, and temporal and spatial dimensionality in development. To study student learning, a curriculum was developed incorporating…

  11. Effects of temperature on embryonic and early larval growth and development in the rough-skinned newt (Taricha granulosa).

    Science.gov (United States)

    Smith, Geoffrey D; Hopkins, Gareth R; Mohammadi, Shabnam; M Skinner, Heather; Hansen, Tyler; Brodie, Edmund D; French, Susannah S

    2015-07-01

    We investigated the effects of temperature on the growth and development of embryonic and early larval stages of a western North American amphibian, the rough-skinned newt (Taricha granulosa). We assigned newt eggs to different temperatures (7, 14, or 21°C); after hatching, we re-assigned the newt larvae into the three different temperatures. Over the course of three to four weeks, we measured total length and developmental stage of the larvae. Our results indicated a strong positive relationship over time between temperature and both length and developmental stage. Importantly, individuals assigned to cooler embryonic temperatures did not achieve the larval sizes of individuals from the warmer embryonic treatments, regardless of larval temperature. Our investigation of growth and development at different temperatures demonstrates carry-over effects and provides a more comprehensive understanding of how organisms respond to temperature changes during early development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Effects of latex from "Amapazeiro"Parahancornia amapa (Apocynaceae) on blowfly Chrysomya megacephala (Diptera: Calliphoridae) post-embryonic development.

    Science.gov (United States)

    Mendonça, Paloma M; Lima, Mariana G; Albuquerque, Luis R M; Carvalho, Mario G; Queiroz, Margareth M C

    2011-06-10

    Nowadays, insect control is usually carried out using chemical insecticides, but insect resistance and other negative side effects have prompted the search for alternatives. Biopesticides provide a positive alternative to synthetic pesticides because they have low impact on the environmental, low toxicity to humans and low costs among other advantages. This research was carried out to evaluate the activity of Parahancornia amapa (Huber) Ducke (Apocynaceae) lyophilized latex on the post embryonic development of Chrysomya megacephala (F.) (Diptera: Calliphoridae). Larvae treated with 1.0% latex showed a shorter post embryonic development period (larval, pupal and newly hatched larvae to adult); whereas larvae treated with 3.0% latex provoked a prolongation of these periods. Viability (53%) was also very low at the newly hatched larvae to adult period for larvae treated with 3.0% latex, indicating that latex from P. amapa at high concentrations could change C. megacephala post embryonic development. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Promotion of human early embryonic development and blastocyst outgrowth in vitro using autocrine/paracrine growth factors.

    Science.gov (United States)

    Kawamura, Kazuhiro; Chen, Yuan; Shu, Yimin; Cheng, Yuan; Qiao, Jie; Behr, Barry; Pera, Renee A Reijo; Hsueh, Aaron J W

    2012-01-01

    Studies using animal models demonstrated the importance of autocrine/paracrine factors secreted by preimplantation embryos and reproductive tracts for embryonic development and implantation. Although in vitro fertilization-embryo transfer (IVF-ET) is an established procedure, there is no evidence that present culture conditions are optimal for human early embryonic development. In this study, key polypeptide ligands known to be important for early embryonic development in animal models were tested for their ability to improve human early embryo development and blastocyst outgrowth in vitro. We confirmed the expression of key ligand/receptor pairs in cleavage embryos derived from discarded human tri-pronuclear zygotes and in human endometrium. Combined treatment with key embryonic growth factors (brain-derived neurotrophic factor, colony-stimulating factor, epidermal growth factor, granulocyte macrophage colony-stimulating factor, insulin-like growth factor-1, glial cell-line derived neurotrophic factor, and artemin) in serum-free media promoted >2.5-fold the development of tri-pronuclear zygotes to blastocysts. For normally fertilized embryos, day 3 surplus embryos cultured individually with the key growth factors showed >3-fold increases in the development of 6-8 cell stage embryos to blastocysts and >7-fold increase in the proportion of high quality blastocysts based on Gardner's criteria. Growth factor treatment also led to a 2-fold promotion of blastocyst outgrowth in vitro when day 7 surplus hatching blastocysts were used. When failed-to-be-fertilized oocytes were used to perform somatic cell nuclear transfer (SCNT) using fibroblasts as donor karyoplasts, inclusion of growth factors increased the progression of reconstructed SCNT embryos to >4-cell stage embryos. Growth factor supplementation of serum-free cultures could promote optimal early embryonic development and implantation in IVF-ET and SCNT procedures. This approach is valuable for infertility

  14. Design and Development of a Novel Upper-Limb Cycling Prosthesis

    Directory of Open Access Journals (Sweden)

    Akira Tiele

    2017-11-01

    Full Text Available The rise in popularity of the Paralympics in recent years has created a need for effective, low-cost sports-prosthetic devices for upper-limb amputees. There are various opportunities for lower-limb amputees to participate in cycling; however, there are only few options for those with upper-limb amputations. If the individual previously participated in cycling, a cycling-specific prosthesis could allow these activities to be integrated into rehabilitation methods. This article describes the processes involved with designing, developing and manufacturing such a prosthesis. The fundamental needs of people with upper-limb amputation were assessed and realised in the prototype of a transradial terminal device with two release mechanisms, including a sliding mechanism (for falls and minor collisions and clamping mechanism (for head-on collisions. The sliding mechanism requires the rider to exert approximately 200 N, while the clamping mechanism requires about 700 N. The force ranges can be customised to match rider requirements. Experiments were conducted in a controlled environment to demonstrate stability of the device during normal cycling. Moreover, a volunteer test-rider was able to successfully activate the release mechanism during a simulated emergency scenario. The development of this prosthesis has the potential to enable traumatic upper-limb amputees to participate in cycling for rehabilitation or recreation.

  15. Design and Development of a Novel Upper-Limb Cycling Prosthesis.

    Science.gov (United States)

    Tiele, Akira; Soni-Sadar, Shivam; Rowbottom, Jack; Patel, Shilen; Mathewson, Edward; Pearson, Samuel; Hutchins, David; Head, John; Hutchins, Stephen

    2017-11-16

    The rise in popularity of the Paralympics in recent years has created a need for effective, low-cost sports-prosthetic devices for upper-limb amputees. There are various opportunities for lower-limb amputees to participate in cycling; however, there are only few options for those with upper-limb amputations. If the individual previously participated in cycling, a cycling-specific prosthesis could allow these activities to be integrated into rehabilitation methods. This article describes the processes involved with designing, developing and manufacturing such a prosthesis. The fundamental needs of people with upper-limb amputation were assessed and realised in the prototype of a transradial terminal device with two release mechanisms, including a sliding mechanism (for falls and minor collisions) and clamping mechanism (for head-on collisions). The sliding mechanism requires the rider to exert approximately 200 N, while the clamping mechanism requires about 700 N. The force ranges can be customised to match rider requirements. Experiments were conducted in a controlled environment to demonstrate stability of the device during normal cycling. Moreover, a volunteer test-rider was able to successfully activate the release mechanism during a simulated emergency scenario. The development of this prosthesis has the potential to enable traumatic upper-limb amputees to participate in cycling for rehabilitation or recreation.

  16. Expression patterns of Neil3 during embryonic brain development and neoplasia

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    Bjørås Magnar

    2009-05-01

    Full Text Available Abstract Background The base excision repair pathway is responsible for repairing small DNA base lesions caused by endogenous and exogenous damaging agents. Repair is initiated by DNA glycosylases that recognize and remove the lesions. NEIL3 is one of 11 mammalian DNA glycosylases identified to date and it was discovered on the basis of sequence homology to the E. coli Fpg and Nei glycosylases. Difficulties in purifying the protein have limited its biochemical characterization and in contrast to the other glycosylases, its function remains unclear. Results In this study we describe the expression pattern of Neil3 during mouse embryonic development with special focus on brain development. We have also looked at the expression of NEIL3 in several normal and tumor tissues. Quantitative real-time PCR and in situ hybridization revealed that Neil3 was highly expressed at embryonic days 12–13, when neurogenesis starts. The expression decreased during development and in the adult brain,Neil3 could not be detected in any of the brain areas examined by quantitative real-time PCR. During embryogenesis and in newborn mice specific expression was observed in areas known to harbour neural stem and progenitor cells such as the subventricular zone and the dentate gyrus. Finally, NEIL3 expression was higher in tumors compared to normal tissues, except for testis and pancreas. Conclusion Our findings indicate that mammalian NEIL3 is specifically expressed in brain areas where neurogenesis takes place during development and that its expression is tightly regulated both temporally and spatially. In addition, NEIL3 seems to be upregulated in tumor tissues compared to normal tissues. Altogether, mammalian NEIL3 seems to be highly expressed in cells with high proliferative potential.

  17. Development of retroviral vectors for tissue-restricted expression in chicken embryonic gonads.

    Directory of Open Access Journals (Sweden)

    Luke S Lambeth

    Full Text Available The chicken embryo has long been a useful model organism for studying development, including sex determination and gonadal differentiation. However, manipulating gene expression specifically in the embryonic avian gonad has been difficult. The viral vector RCASBP can be readily used for embryo-wide transgene expression; however global mis-expression using this method can cause deleterious off-target effects and embryo-lethality. In an attempt to develop vectors for the over-expression of sequences in chicken embryonic urogenital tissues, the viral vector RCANBP was engineered to contain predicted promoter sequences of gonadal-expressed genes. Several promoters were analysed and it was found that although the SF1 promoter produced a tissue-restricted expression pattern that was highest in the mesonephros and liver, it was also higher in the gonads compared to the rest of the body. The location of EGFP expression from the SF1 promoter overlapped with several key gonad-expressed sex development genes; however expression was generally low-level and was not seen in all gonadal cells. To further validate this sequence the key testis determinant DMRT1 was over-expressed in female embryos, which due to insufficient levels had no effect on gonad development. The female gene aromatase was then over-expressed in male embryos, which disrupted the testis pathway as demonstrated by a reduction in AMH protein. Taken together, although these data showed that the SF1 promoter can be used for functional studies in ovo, a stronger promoter sequence would likely be required for the functional analysis of gonad genes that require high-level expression.

  18. Spatiotemporal distribution of proliferation, proapoptotic and antiapoptotic factors in the early human limb development.

    Science.gov (United States)

    Bečić, Tina; Bilan, Kanito; Mardešić, Snježana; Vukojević, Katarina; Saraga-Babić, Mirna

    2016-06-01

    Involvement of proliferation and apoptosis in the human limb development was analyzed electronmicroscopically and immunohistochemically in histological sections of 8 human embryos, 4(th) -10(th) week old, using apoptotic (caspase-3, AIF, BAX), anti-apoptotic (Bcl-2) and proliferation (Ki-67) markers, and TUNEL method. The data were analyzed by Mann-Whitney test, Kruskal-Wallis and Dunn's post hoc test. Initially, developing human limbs consisted of mesenchymal core and surface ectoderm with apical ectodermal ridge (AER). During progression of development, strong proliferation activity gradually decreased in the mesenchyme (from 78% to 68%) and in the epithelium (from 62% to 42%), while in the differentiating finger cartilages proliferation was constantly low (26-7%). Apoptotic caspase-3 and AIF-positive cells characterized mesenchyme and AER at earliest stages, while during digit separation they appeared in interdigital mesenchyme as well. Strong Bcl-2 expression was observed in AER, subridge mesenchyme and phalanges, while BAX expression charaterized limb areas undergoing apoptosis. Ultrastructurally, proliferating cells showed mitotic figures, while apoptotic cells were characterized by nuclear fragmentation. Macrophages were observed around the apoptotic cells. We suggest that intense proliferation enables growth and elongation of human limb primordia, and differential growth of digits. Both caspase-3 and AIF-dependant pathways of cell death control the extent of AER and numer of cells in the subridge mesenchyme at earliest developmental stages, as well as process of digit separation at later stages of limb development. Spatio-temporal co-expresson of Bcl-2 and BAX indicates their role in suppression of apoptosis and selective stimulation of growth during human limb morphogenesis. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. Expression and function of the SDF-1 chemokine receptors CXCR4 and CXCR7 during mouse limb muscle development and regeneration.

    Science.gov (United States)

    Hunger, Conny; Ödemis, Veysel; Engele, Jürgen

    2012-10-15

    The chemokine, SDF-1/CXCL12, and its receptor, CXCR4, have been implied to play major roles during limb myogenesis. This concept was recently challenged by the identification of CXCR7 as an alternative SDF-1 receptor, which can either act as a scavenger receptor, a modulator of CXCR4, or an active chemokine receptor. We have now re-examined this issue by determining whether SDF-1 would signal to C2C12 myoblasts and subsequently influence their differentiation via CXCR4 and/or CXCR7. In addition, we have analyzed CXCR7, CXCR4, and SDF-1 expression in developing and injured mouse limb muscles. We demonstrate that in undifferentiated C2C12 cells, SDF-1-dependent cell signaling and resulting inhibitory effects on myogenic differentiation are entirely mediated by CXCR4. We further demonstrate that CXCR7 expression increases in differentiating C2C12 cells, which in turn abrogates CXCR4 signaling. Moreover, consistent with the view that CXCR4 and CXCR7 control limb myogenesis in vivo by similar mechanisms, we found that CXCR4 expression is the highest in late embryonic hindlimb muscles and drops shortly after birth when secondary muscle growth terminates. Vice versa, CXCR7 expression increased perinatally and persisted into adult life. Finally, underscoring the role of the SDF-1 system in muscle regeneration, we observed that SDF-1 is continuously expressed by endomysial cells of postnatal and adult muscle fibers. Analysis of dystrophin-deficient mdx mice additionally revealed that muscle regeneration is associated with muscular re-expression of CXCR4. The apparent tight control of limb muscle development and regeneration by CXCR4 and CXCR7 points to these chemokine receptors as promising therapeutic targets for certain muscle disorders. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. An Evaluation of Significance of Herbal Acupuncture on Treating Limb Impediment Among the Children with Development Disabilities

    Directory of Open Access Journals (Sweden)

    Huh Young-Jin

    2004-02-01

    Full Text Available Objectives : This study was conducted to establish a standard and classify suitability in the treatment of limb impediment among the children with development disabilities using bee venom and eight principles herbal acupuncture. Methods : 10 patients with pediatric development disabilities with limb impediment as the main symptoms were chosen in this study. Bee venom herbal acupuncture and eight principles herbal acupuncture treatments were rendered and evaluated responses as well as pursuing most proper treatment methods. Results : 1. Bee venom herbal acupuncture showed a significant effects when used as supplement treatment technique for the children with partial movement, but insignificant for the children whom were unable to move. 2. Bee venom was effective for severe limb impediment and limb asthenia, whileas eight principles herbal acupuncture effective for mild limb impediment and spasticity. 3. Bee venom herbal acupuncture used in conjunction with eight principles herbal acupuncture for treating limb impediment among the children with development disabilities showed general improvement by intensifying muscular strength.

  1. mRNA fragments in in vitro culture media are associated with bovine preimplantation embryonic development.

    Science.gov (United States)

    Kropp, Jenna; Khatib, Hasan

    2015-01-01

    In vitro production (IVP) systems have been used to bypass problems of fertilization and early embryonic development. However, embryos produced by IVP are commonly selected for implantation based on morphological assessment, which is not a strong indicator of establishment and maintenance of pregnancy. Thus, there is a need to identify additional indicators of embryonic developmental potential. Previous studies have identified microRNA expression in in vitro culture media to be indicative of embryo quality in both bovine and human embryos. Like microRNAs, mRNAs have been shown to be secreted from cells into the extracellular environment, but it is unknown whether or not these RNAs are secreted by embryos. Thus, the objective of the present study was to determine whether mRNAs are secreted into in vitro culture media and if their expression in the media is indicative of embryo quality. In vitro culture medium was generated and collected from both blastocyst and degenerate (those which fail to develop from the morula to blastocyst stage) embryos. Small-RNA sequencing revealed that many mRNA fragments were present in the culture media. A total of 17 mRNA fragments were differentially expressed between blastocyst and degenerate conditioned media. Differential expression was confirmed by quantitative real-time PCR for fragments of mRNA POSTN and VSNL-1, in four additional biological replicates of media. To better understand the mechanisms of mRNA secretion into the media, the expression of a predicted RNA binding protein of POSTN, PUM2, was knocked down using an antisense oligonucleotide gapmer. Supplementation of a PUM2 gapmer significantly reduced blastocyst development and decreased secretion of POSTN mRNA into the media. Overall, differential mRNA expression in the media was repeatable and sets the framework for future study of mRNA biomarkers in in vitro culture media to improve predictability of reproductive performance.

  2. Evidence for the involvement of fibroblast growth factor 10 in lipofibroblast formation during embryonic lung development.

    Science.gov (United States)

    Al Alam, Denise; El Agha, Elie; Sakurai, Reiko; Kheirollahi, Vahid; Moiseenko, Alena; Danopoulos, Soula; Shrestha, Amit; Schmoldt, Carole; Quantius, Jennifer; Herold, Susanne; Chao, Cho-Ming; Tiozzo, Caterina; De Langhe, Stijn; Plikus, Maksim V; Thornton, Matthew; Grubbs, Brendan; Minoo, Parviz; Rehan, Virender K; Bellusci, Saverio

    2015-12-01

    Lipid-containing alveolar interstitial fibroblasts (lipofibroblasts) are increasingly recognized as an important component of the epithelial stem cell niche in the rodent lung. Although lipofibroblasts were initially believed merely to assist type 2 alveolar epithelial cells in surfactant production during neonatal life, recent evidence suggests that these cells are indispensable for survival and growth of epithelial stem cells during adulthood. Despite increasing interest in lipofibroblast biology, little is known about their cellular origin or the molecular pathways controlling their formation during embryonic development. Here, we show that a population of lipid-droplet-containing stromal cells emerges in the developing mouse lung between E15.5 and E16.5. This is accompanied by significant upregulation, in the lung mesenchyme, of peroxisome proliferator-activated receptor gamma (master switch of lipogenesis), adipose differentiation-related protein (marker of mature lipofibroblasts) and fibroblast growth factor 10 (previously shown to identify a subpopulation of lipofibroblast progenitors). We also demonstrate that although only a subpopulation of total embryonic lipofibroblasts derives from Fgf10(+) progenitor cells, in vivo knockdown of Fgfr2b ligand activity and reduction in Fgf10 expression lead to global reduction in the expression levels of lipofibroblast markers at E18.5. Constitutive Fgfr1b knockouts and mutants with conditional partial inactivation of Fgfr2b in the lung mesenchyme reveal the involvement of both receptors in lipofibroblast formation and suggest a possible compensation between the two receptors. We also provide data from human fetal lungs to demonstrate the relevance of our discoveries to humans. Our results reveal an essential role for Fgf10 signaling in the formation of lipofibroblasts during late lung development. © 2015. Published by The Company of Biologists Ltd.

  3. Variation in maternal effects and embryonic development rates among passerine species

    Science.gov (United States)

    Martin, T.E.; Schwabl, H.

    2008-01-01

    Embryonic development rates are reflected by the length of incubation period in birds, and these vary substantially among species within and among geographical regions. The incubation periods are consistently shorter in North America (Arizona study site) than in tropical (Venezuela) and subtropical (Argentina) South America based on the study of 83 passerine species in 17 clades. Parents, mothers in particular, may influence incubation periods and resulting offspring quality through proximate pathways, while variation in maternal strategies among species can result from selection by adult and offspring mortality. Parents of long-lived species, as is common in the tropics and subtropics, may be under selection to minimize costs to themselves during incubation. Indeed, time spent incubating is often lower in the tropical and subtropical species than the related north temperate species, causing cooler average egg temperatures in the southern regions. Decreased egg temperatures result in longer incubation periods and reflect a cost imposed on offspring by parents because energy cost to the embryo and risk of offspring predation are both increased. Mothers may adjust egg size and constituents as a means to partially offset such costs. For example, reduced androgen concentrations in egg yolks may slow development rates, but may enhance offspring quality through physiological trade-offs that may be particularly beneficial in longer-lived species, as in the tropics and subtropics. We provide initial data to show that yolks of tropical birds contain substantially lower concentrations of growth-promoting androgens than north temperate relatives. Thus, maternal (and parental) effects on embryonic development rates may include contrasting and complementary proximate influences on offspring quality and deserve further field study among species. ?? 2007 The Royal Society.

  4. Cell cycle regulation and cytoskeletal remodelling are critical processes in the nutritional programming of embryonic development.

    Science.gov (United States)

    Swali, Angelina; McMullen, Sarah; Hayes, Helen; Gambling, Lorraine; McArdle, Harry J; Langley-Evans, Simon C

    2011-01-01

    Many mechanisms purport to explain how nutritional signals during early development are manifested as disease in the adult offspring. While these describe processes leading from nutritional insult to development of the actual pathology, the initial underlying cause of the programming effect remains elusive. To establish the primary drivers of programming, this study aimed to capture embryonic gene and protein changes in the whole embryo at the time of nutritional insult rather than downstream phenotypic effects. By using a cross-over design of two well established models of maternal protein and iron restriction we aimed to identify putative common "gatekeepers" which may drive nutritional programming.Both protein and iron deficiency in utero reduced the nephron complement in adult male Wistar and Rowett Hooded Lister rats (Pproteomic and pathway analyses identified diet-specific and strain-specific gatekeeper genes, proteins and processes which shared a common association with the regulation of the cell cycle, especially the G1/S and G2/M checkpoints, and cytoskeletal remodelling. A cell cycle-specific PCR array confirmed the down-regulation of cyclins with protein restriction and the up-regulation of apoptotic genes with iron deficiency.The timing and experimental design of this study have been carefully controlled to isolate the common molecular mechanisms which may initiate the sequelae of events involved in nutritional programming of embryonic development. We propose that despite differences in the individual genes and proteins affected in each strain and with each diet, the general response to nutrient deficiency in utero is perturbation of the cell cycle, at the level of interaction with the cytoskeleton and the mitotic checkpoints, thereby diminishing control over the integrity of DNA which is allowed to replicate. These findings offer novel insight into the primary causes and mechanisms leading to the pathologies which have been identified by previous

  5. Cell cycle regulation and cytoskeletal remodelling are critical processes in the nutritional programming of embryonic development.

    Directory of Open Access Journals (Sweden)

    Angelina Swali

    Full Text Available Many mechanisms purport to explain how nutritional signals during early development are manifested as disease in the adult offspring. While these describe processes leading from nutritional insult to development of the actual pathology, the initial underlying cause of the programming effect remains elusive. To establish the primary drivers of programming, this study aimed to capture embryonic gene and protein changes in the whole embryo at the time of nutritional insult rather than downstream phenotypic effects. By using a cross-over design of two well established models of maternal protein and iron restriction we aimed to identify putative common "gatekeepers" which may drive nutritional programming.Both protein and iron deficiency in utero reduced the nephron complement in adult male Wistar and Rowett Hooded Lister rats (P<0.05. This occurred in the absence of damage to the glomerular ultrastructure. Microarray, proteomic and pathway analyses identified diet-specific and strain-specific gatekeeper genes, proteins and processes which shared a common association with the regulation of the cell cycle, especially the G1/S and G2/M checkpoints, and cytoskeletal remodelling. A cell cycle-specific PCR array confirmed the down-regulation of cyclins with protein restriction and the up-regulation of apoptotic genes with iron deficiency.The timing and experimental design of this study have been carefully controlled to isolate the common molecular mechanisms which may initiate the sequelae of events involved in nutritional programming of embryonic development. We propose that despite differences in the individual genes and proteins affected in each strain and with each diet, the general response to nutrient deficiency in utero is perturbation of the cell cycle, at the level of interaction with the cytoskeleton and the mitotic checkpoints, thereby diminishing control over the integrity of DNA which is allowed to replicate. These findings offer novel

  6. Endogenous hydrogen peroxide production in the epithelium of the developing embryonic lens.

    Science.gov (United States)

    Basu, Subhasree; Rajakaruna, Suren; Dickinson, Bryan C; Chang, Christopher J; Menko, A Sue

    2014-01-01

    Hydrogen peroxide (H2O2) is an endogenously produced reactive oxygen species (ROS) present in a variety of mammalian systems. This particular ROS can play dichotomous roles, being beneficial in some cases and deleterious in others, which reflects the level and location of H2O2 production. While much is known about the redox regulation of ROS by antioxidant and repair systems in the lens, little is known about the endogenous production of H2O2 in embryonic lens tissue or the physiologic relevance of endogenous H2O2 to lens development. This gap in knowledge exists primarily from a lack of reagents that can specifically detect endogenous H2O2 in the intact lens. Here, using a recently developed chemoselective fluorescent boronate probe, peroxyfluor-6 acetoxymethyl ester (PF6-AM), which selectively detects H2O2 over related ROS, we examined the endogenous H2O2 signals in the embryonic lens. Embryonic day 10 chick whole lenses in ex vivo organ culture and lens epithelial cells in primary culture were loaded with the H2O2 probe PF6-AM. To determine the relationship between localization of mitochondria with active membrane potential and the region of H2O2 production in the lens, cells were exposed to the mitochondrial probe MitoTracker Red CMXRos together with PF6-AM. Diphenyleneiodonium (DPI), a flavin inhibitor that blocks generation of intracellular ROS production, was used to confirm that the signal from PF6-AM was due to endogenous ROS production. All imaging was performed by live confocal microscopy. PF6-AM detected endogenous H2O2 in lens epithelial cells in whole lenses in ex vivo culture and in lens epithelial cells grown in primary culture. No endogenous H2O2 signal could be detected in differentiating lens fiber cells with this probe. Treatment with DPI markedly attenuated the fluorescence signal from the peroxide-specific probe PF6-AM in the lens epithelium, suggesting that basal generation of ROS occurs in this region. The lens epithelial cells producing an

  7. Cortical morphogenesis during embryonic development is regulated by miR-34c and miR-204

    DEFF Research Database (Denmark)

    Venø, Morten T; Venø, Susanne T; Rehberg, Kati

    2017-01-01

    The porcine brain closely resembles the human brain in aspects such as development and morphology. Temporal miRNA profiling in the developing embryonic porcine cortex revealed a distinct set of miRNAs, including miR-34c and miR-204, which exhibited a highly specific expression profile across...

  8. Metallic nickel nanoparticles and their effect on the embryonic development of the sea urchin Paracentrotus lividus

    International Nuclear Information System (INIS)

    Kanold, Julia Maxi; Wang, Jiabin; Brümmer, Franz; Šiller, Lidija

    2016-01-01

    The presence of nanoparticles in many industrial applications and daily products is making it nowadays crucial to assess their impact when exposed to the environment. Metallic nickel nanoparticles (Ni NPs) are of high industrial interest due to their ability to catalyze the reversible hydration of CO 2 to carbonic acid at ambient conditions. We characterized metallic Ni NPs by XRD, HRTEM and EDS and determined the solubility of free nickel ions from 3 mg/L metallic Ni NPs in seawater by ICP-MS over 96 h, which was below 3%. Further, embryonic development of the sea urchin Paracentrotus lividus was investigated for 48 h in the presence of metallic Ni NPs (0.03 mg/L to 3 mg/L), but no lethal effects were observed. However, 3 mg/L metallic Ni NPs caused a size reduction similar to 1.2 mg/L NiCl 2 *6 H 2 O. The obtained results contribute to current studies on metallic Ni NPs and point to their consequences for the marine ecosystem. - Highlights: • Low solubility of nickel ions from metallic nickel nanoparticles in seawater. • No lethality of sea urchin embryos up to 3 mg/L metallic nickel nanoparticles. • Considerable size reduction after 48 h was comparable to the reduction for 1.2 mg/L nickel salt. • Contributes to the overall understanding of metallic Ni NPs in the marine environment. - Metallic nickel nanoparticles display weak dissolution rates in seawater, but higher concentrations resulted in similar effects on sea urchin embryonic development as nickel salt.

  9. Impact of electromagnetic radiation exposure during pregnancy on embryonic skeletal development in rats

    Directory of Open Access Journals (Sweden)

    Ali SAEED H Alchalabi

    2017-03-01

    Full Text Available Objective: To evaluate the teratogenic effect of mobile phone radiation exposure during pregnancy on embryonic skeletal development at the common used mobile phone frequency in our environment. Methods: Sixty female Sprague-Dawley rats were distributed into three experiment groups; control and two exposed groups (1 h/day, 2 h/day exposure groups (n=20/ each group and exposed to whole body radiation during gestation period from day 1- day 20. Electromagnetic radiofrequency signal generator was used to generate 1 800 MHz GSM-like signals at specific absorption rate value 0.974 W/kg. Animals were exposed during experiment in an especial designed Plexiglas box (60 cm × 40 cm × 30 cm. At the end of exposure duration at day 20 of pregnancy animals were sacrificed and foetuses were removed, washed with normal saline and processed to Alizarin red and Alcian blue stain. Skeleton specimens were examined under a stereo microscope and skeleton's snaps were being carefully captured by built in camera fixed on the stereo microscope. Results: Intrauterine exposure to electromagnetic radiation lead to variation in degree of ossification, mineralization, formation of certain parts of the skeleton majorly in head and lesser in other parts. Deformity and absence of formation of certain bones in the head, ribs, and coccygeal vertebrae were recorded in skeleton of foetuses from exposed dams compare to control group. Conclusions: The electromagnetic radiation exposure during pregnancy alter the processes of bone mineralization and the intensity of bone turnover processes, and thus impact embryonic skeleton formation and development directly.

  10. Impaired embryonic haematopoiesis yet normal arterial development in the absence of the Notch ligand Jagged1

    DEFF Research Database (Denmark)

    Robert-Moreno, Àlex; Robert-Moreno, Àlex; Guiu, Jordi

    2008-01-01

    Specific deletion of Notch1 and RBPjκ in the mouse results in abrogation of definitive haematopoiesis concomitant with the loss of arterial identity at embryonic stage. As prior arterial determination is likely to be required for the generation of embryonic haematopoiesis, it is difficult...

  11. Effects of temperature on embryonic development of lake herring (Coregonus artedii)

    Science.gov (United States)

    Colby, Peter J.; Brooke, L.T.

    1973-01-01

    Embryonic development of lake herring (Coregonus artedii) was observed in the laboratory at 13 constant temperatures from 0.0 to 12.1 C and in Pickerel Lake (Washtenaw County, Michigan) at natural temperature regimes. Rate of development during incubation was based on progression of the embryos through 20 identifiable stages. An equation was derived to predict development stage at constant temperatures, on the general assumption that development stage (DS) is a function of time (days, D) and temperature (T). The equation should also be useful in interpreting estimates from future regressions that include other environmental variables that affect egg development. A second regression model, derived primarily for fluctuating temperatures, related development rate for stage j (DRj), expressed as the reciprocal of time, to temperature (x). The generalized equation for a development stage is: DRj = abx cx2 dx3. In general, time required for embryos to reach each stage of development in Pickerel Lake agreed closely with the time predicted from this equation, derived from our laboratory observations. Hatching time was predicted within 1 day in 1969 and within 2 days in 1970. We used the equations derived with the second model to predict the effect of the superimposition of temperature increases of 1 and 2 C on the measured temperatures in Pickerel Lake. Conceivably, hatching dates could be affected sufficiently to jeopardize the first feeding of lake herring through loss of harmony between hatching date and seasonal food availability.

  12. Development of a hybrid strength training technique for paretic lower-limb muscles

    NARCIS (Netherlands)

    Bennett, T. L.; Glaser, R. M.; Janssen, T. W J; Couch, W. P.; Herr, C. J.; Almeyda, J. W.; Petrofsky, S. H.; Akuthota, P.

    1996-01-01

    A hybrid resistance exercise technique for strength training of patients with lower-limb paresis was developed. It consists of electrical stimulation-induced contractions (ESIC) superimposed on voluntary contractions to increase recruitment of motor units and the functional load capability of

  13. Regulation of H3K27me3 and H3K4me3 during early porcine embryonic development

    DEFF Research Database (Denmark)

    Gao, Yu; Hyttel, Poul; Hall, Vanessa Jane

    2010-01-01

    The epigenetic marks H3K27me3 and H3K4me3 are important repressive and permissive histone modifications, respectively, which are involved in gene regulation such as Hox gene expression during embryonic development. In this study, we investigated the global levels of these two histone modifications......, HOXA3, HOXA7, HOXA10, HOXB4, HOXB7, HOXC8, HOXD8, and HOXD10 was investigated. We found that global levels of H3K27me3 decreased from the 1- to the 4-cell stage, corresponding to the time of major embryonic genome activation. Subsequently, the levels increased in hatched blastocysts, particularly...... porcine embryonic genome activation, whereas, H3K27me3 may be involved in initial cell lineage segregation in the blastocyst....

  14. Distinctive Roles of Canonical and Noncanonical Wnt Signaling in Human Embryonic Cardiomyocyte Development

    Directory of Open Access Journals (Sweden)

    Silvia Mazzotta

    2016-10-01

    Full Text Available Wnt signaling is a key regulator of vertebrate heart development; however, specific roles for human cardiomyocyte development remain uncertain. Here we use human embryonic stem cells (hESCs to analyze systematically in human cardiomyocyte development the expression of endogenous Wnt signaling components, monitor pathway activity, and dissect stage-specific requirements for canonical and noncanonical Wnt signaling mechanisms using small-molecule inhibitors. Our analysis suggests that WNT3 and WNT8A, via FZD7 and canonical signaling, regulate BRACHYURY expression and mesoderm induction; that WNT5A/5B, via ROR2 and noncanonical signaling, regulate MESP1 expression and cardiovascular development; and that later in development WNT2, WNT5A/5B, and WNT11, via FZD4 and FZD6, regulate functional cardiomyocyte differentiation via noncanonical Wnt signaling. Our findings confirm in human development previously proposed roles for canonical Wnt signaling in sequential stages of vertebrate cardiomyogenesis, and identify more precise roles for noncanonical signaling and for individual Wnt signal and Wnt receptor genes in human cardiomyocyte development.

  15. CTCF counter-regulates cardiomyocyte development and maturation programs in the embryonic heart.

    Science.gov (United States)

    Gomez-Velazquez, Melisa; Badia-Careaga, Claudio; Lechuga-Vieco, Ana Victoria; Nieto-Arellano, Rocio; Tena, Juan J; Rollan, Isabel; Alvarez, Alba; Torroja, Carlos; Caceres, Eva F; Roy, Anna R; Galjart, Niels; Delgado-Olguin, Paul; Sanchez-Cabo, Fatima; Enriquez, Jose Antonio; Gomez-Skarmeta, Jose Luis; Manzanares, Miguel

    2017-08-01

    Cardiac progenitors are specified early in development and progressively differentiate and mature into fully functional cardiomyocytes. This process is controlled by an extensively studied transcriptional program. However, the regulatory events coordinating the progression of such program from development to maturation are largely unknown. Here, we show that the genome organizer CTCF is essential for cardiogenesis and that it mediates genomic interactions to coordinate cardiomyocyte differentiation and maturation in the developing heart. Inactivation of Ctcf in cardiac progenitor cells and their derivatives in vivo during development caused severe cardiac defects and death at embryonic day 12.5. Genome wide expression analysis in Ctcf mutant hearts revealed that genes controlling mitochondrial function and protein production, required for cardiomyocyte maturation, were upregulated. However, mitochondria from mutant cardiomyocytes do not mature properly. In contrast, multiple development regulatory genes near predicted heart enhancers, including genes in the IrxA cluster, were downregulated in Ctcf mutants, suggesting that CTCF promotes cardiomyocyte differentiation by facilitating enhancer-promoter interactions. Accordingly, loss of CTCF disrupts gene expression and chromatin interactions as shown by chromatin conformation capture followed by deep sequencing. Furthermore, CRISPR-mediated deletion of an intergenic CTCF site within the IrxA cluster alters gene expression in the developing heart. Thus, CTCF mediates local regulatory interactions to coordinate transcriptional programs controlling transitions in morphology and function during heart development.

  16. Mdm4 (Mdmx) regulates p53-induced growth arrest and neuronal cell death during early embryonic mouse development

    DEFF Research Database (Denmark)

    Migliorini, Domenico; Lazzerini Denchi, Eros; Danovi, Davide

    2002-01-01

    We report here the characterization of a mutant mouse line with a specific gene trap event in the Mdm4 locus. Absence of Mdm4 expression results in embryonic lethality (10.5 days postcoitum [dpc]), which was rescued by transferring the Mdm4 mutation into a Trp53-null background. Mutant embryos were...... incorporation, these data suggest a block of mutant embryo cells in the G(1) phase of the cell cycle. Accordingly, Mdm4-deficient mouse embryonic fibroblasts manifested a greatly reduced proliferative capacity in culture. Moreover, extensive p53-dependent cell death was specifically detected in the developing...

  17. Mdm4 (Mdmx) regulates p53-induced growth arrest and neuronal cell death during early embryonic mouse development

    DEFF Research Database (Denmark)

    Migliorini, Domenico; Lazzerini Denchi, Eros; Danovi, Davide

    2002-01-01

    incorporation, these data suggest a block of mutant embryo cells in the G(1) phase of the cell cycle. Accordingly, Mdm4-deficient mouse embryonic fibroblasts manifested a greatly reduced proliferative capacity in culture. Moreover, extensive p53-dependent cell death was specifically detected in the developing......We report here the characterization of a mutant mouse line with a specific gene trap event in the Mdm4 locus. Absence of Mdm4 expression results in embryonic lethality (10.5 days postcoitum [dpc]), which was rescued by transferring the Mdm4 mutation into a Trp53-null background. Mutant embryos were...

  18. Aspects of embryonic and larval development in bighead carp Hypophthalmichthys nobilis and silver carp Hypophthalmichthys molitrix

    Science.gov (United States)

    George, Amy E.; Chapman, Duane C.

    2013-01-01

    As bighead carp Hypophthalmichthys nobilis and silver carp H. molitrix (the bigheaded carps) are poised to enter the Laurentian Great Lakes and potentially damage the region’s economically important fishery, information on developmental rates and behaviors of carps is critical to assessing their ability to establish sustainable populations within the Great Lakes basin. In laboratory experiments, the embryonic and larval developmental rates, size, and behaviors of bigheaded carp were tracked at two temperature treatments, one “cold” and one “warm”. Developmental rates were computed using previously described stages of development and the cumulative thermal unit method. Both species have similar thermal requirements, with a minimum developmental temperature for embryonic stages of 12.1° C for silver carp and 12.9° C for bighead carp, and 13.3° C for silver carp larval stages and 13.4° C for bighead carp larval stages. Egg size differed among species and temperature treatments, as egg size was larger in bighead carp, and “warm" temperature treatments. The larvae started robust upwards vertical swimming immediately after hatching, interspersed with intervals of sinking. Vertical swimming tubes were used to measure water column distribution, and ascent and descent rates of vertically swimming fish. Water column distribution and ascent and descent rates changed with ontogeny. Water column distribution also showed some diel periodicity. Developmental rates, size, and behaviors contribute to the drift distance needed to fulfill the early life history requirements of bigheaded carps and can be used in conjunction with transport information to assess invasibility of a river.

  19. Development of Evaluation Methods for Lower Limb Function between Aged and Young Using Principal Component Analysis

    Science.gov (United States)

    Nomoto, Yohei; Yamashita, Kazuhiko; Ohya, Tetsuya; Koyama, Hironori; Kawasumi, Masashi

    There is the increasing concern of the society to prevent the fall of the aged. The improvement in aged people's the muscular strength of the lower-limb, postural control and walking ability are important for quality of life and fall prevention. The aim of this study was to develop multiple evaluation methods in order to advise for improvement and maintenance of lower limb function between aged and young. The subjects were 16 healthy young volunteers (mean ± S.D: 19.9 ± 0.6 years) and 10 healthy aged volunteers (mean ± S.D: 80.6 ± 6.1 years). Measurement items related to lower limb function were selected from the items which we have ever used. Selected measurement items of function of lower are distance of extroversion of the toe, angle of flexion of the toe, maximum width of step, knee elevation, moving distance of greater trochanter, walking balance, toe-gap force and rotation range of ankle joint. Measurement items summarized by the principal component analysis into lower ability evaluation methods including walking ability and muscle strength of lower limb and flexibility of ankle. The young group demonstrated the factor of 1.6 greater the assessment score of walking ability compared with the aged group. The young group demonstrated the factor of 1.4 greater the assessment score of muscle strength of lower limb compared with the aged group. The young group demonstrated the factor of 1.2 greater the assessment score of flexibility of ankle compared with the aged group. The results suggested that it was possible to assess the lower limb function of aged and young numerically and to advise on their foot function.

  20. [The function of transcription factor P63 and its signaling pathway during limb development].

    Science.gov (United States)

    Ma, Wei; Tian, Wen

    2014-08-01

    The development of human limb is controlled by several transcription factors and signaling pathways, which are organized in precise time- and space-restricted manners. Recent studies showed that P63 and its signaling pathway play important roles in this process. Transcription factor P63, one member of the P53 family, is characterized by a similar amino acid domain, plays a crucial role in the development of limb and ectoderm differentiation, especially with its DNA binding domain, and sterile alpha motif domains. Mutated P63 gene may produce abnormal transcription factor P63 which can affect the signaling pathway. Furthermore, defective signaling protein in structure and/or quantity is synthesized though the pathway. Eventually, members of the signaling protein family are involved in the regulation of differentiation and development of stem cell, which causes deformity of limbs. In brief, three signaling pathways are related to the digit formation along three axes, including SHH-ZPA, FGFs-AER and Lmx1B-Wnt7a-En1. Each contains numerous signaling molecules which are integrated in self-regulatory modules that assure the acquisition or the correct digit complements. These finding has brought new clues for deciphering the etiology of congenital limb malformation and may provide alternatives for both prevention and treatment.

  1. The Roles of T-Box Genes in Vertebrate Limb Development.

    Science.gov (United States)

    Sheeba, C J; Logan, M P O

    2017-01-01

    Members of the T-box gene family have diverse roles during embryogenesis and many play critical roles in the developing limb. This is exemplified by the fact that, in humans, mutations in T-box genes are associated with several congenital syndromes that include limb defects as part of their characteristic spectrum of abnormalities. T-box genes encode for evolutionary conserved transcription factors that include both transcriptional activators and repressors. The hallmark of T-box gene members is the presence of the eponymous DNA-binding T-box domain. There are 17 mammalian T-box genes, which based on the sequence homology of the T-box domain, are grouped into five subfamilies, namely, T, Tbx1, Tbx2, Tbx6, and Tbr1. At least nine T-box genes are expressed during limb development with distinct and dynamic expression patterns. All four members of Tbx2 subfamily (Tbx2, Tbx3, Tbx4, Tbx5) and three members of Tbx1 (Tbx1, Tbx15, Tbx18), Brachyury (T) and Eomes (Tbr2) are expressed in the developing limb. © 2017 Elsevier Inc. All rights reserved.

  2. Development of a 3D co-culture model using human stem cells for studying embryonic palatal fusion.

    Science.gov (United States)

    Morphogenetic tissue fusion is a critical and complex event in embryonic development and failure of this event leads to birth defects, such as cleft palate. Palatal fusion requires adhesion and subsequent dissolution of the medial epithelial layer of the mesenchymal palatal shelv...

  3. Developing predictions of in vivo developmental toxicity of ToxCast chemicals using mouse embryonic stem cells.

    Science.gov (United States)

    Developing predictions of in vivo developmental toxicity of ToxCast chemicals using mouse embryonic stem cells S. Hunter, M. Rosen, M. Hoopes, H. Nichols, S. Jeffay, K. Chandler1, Integrated Systems Toxicology Division, National Health and Environmental Effects Research Labor...

  4. Storage of Hatching Eggs : Effects of storage and early incubation conditions on egg characteristics, embryonic development, hatchability, and chicken quality

    NARCIS (Netherlands)

    Reijrink, I.A.M.

    2010-01-01

    Key words: egg storage, embryonic development, albumen quality, hatchability, chick quality

    It is well known that an increase in the storage duration increases incubation duration and decreases hatchability and chick quality. The negative effects of prolonged egg storage (> 7 days)

  5. Effect of different cyanobacterial biomasses and their fractions with variable microcystin content on embryonal development of carp (Cyprinus carpio L.)

    Czech Academy of Sciences Publication Activity Database

    Palíková, M.; Krejčí, R.; Hilscherová, Klára; Babica, Pavel; Navrátil, S.; Kopp, R.; Bláha, Luděk

    2007-01-01

    Roč. 81, č. 3 (2007), s. 312-318 ISSN 0166-445X R&D Projects: GA AV ČR KJB6005411 Institutional research plan: CEZ:AV0Z60050516 Keywords : cyanobacterial biomass * embryonal development * common carp Subject RIV: EF - Botanics Impact factor: 2.975, year: 2007

  6. Embryonic development of the skull of the Andean lizard Ptychoglossus bicolor (Squamata, Gymnophthalmidae)

    Science.gov (United States)

    Hernández-Jaimes, Carlos; Jerez, Adriana; Ramírez-Pinilla, Martha Patricia

    2012-01-01

    The study of cranial design and development in Gymnophthalmidae is important to understand the ontogenetic processes behind the morphological diversity of the group and to examine the possible effects of microhabitat use and other ecological parameters, as well as phylogenetic constraints, on skull anatomy. Complete morphological descriptions of embryonic skull development within Gymnophthalmidae are non-existent. Likewise, very little is known about the complete chondrocranium of the family. Herein, the development of the skull of the semi-fossorial lizard Ptychoglossus bicolor is described along with an examination of the chondrocranium of other gymnophthalmid taxa and the teiid Cnemidophorus lemniscatus. Cranial chondrification begins with early condensations in the ethmoid, orbitotemporal and occipital regions of the chondrocranium as well as the viscerocranium. Ossification of the skull starts with elements of the dermatocranium (pterygoid, prefrontal, maxilla and jugal). The orbitosphenoid is the last chondral bone to appear. At birth, the skull is almost completely ossified and exhibits a large frontoparietal fontanelle. In general terms, the chondrocranium of the gymnophthalmids studied is characteristic of lacertiform terrestrial lizards, in spite of their life habits, and resembles the chondrocranium of C. lemniscatus in many aspects. However, the gymnophthalmids show great variation in the orbitosphenoid and a complex nasal capsule. The latter exhibits greater development of some nasal cartilages, which make it more complex than in C. lemniscatus. These characteristics might be related to microhabitat use and the well-developed olfactory and vomeronasal systems observed within this clade. PMID:22881276

  7. Perturbations of heart development and function in cardiomyocytes from human embryonic stem cells with trisomy 21.

    Science.gov (United States)

    Bosman, Alexis; Letourneau, Audrey; Sartiani, Laura; Del Lungo, Martina; Ronzoni, Flavio; Kuziakiv, Rostyslav; Tohonen, Virpi; Zucchelli, Marco; Santoni, Federico; Guipponi, Michel; Dumevska, Biljana; Hovatta, Outi; Antonarakis, Stylianos E; Jaconi, Marisa E

    2015-05-01

    Congenital heart defects (CHD) occur in approximately 50% of patients with Down syndrome (DS); the mechanisms for this occurrence however remain unknown. In order to understand how these defects evolve in early development in DS, we focused on the earliest stages of cardiogenesis to ascertain perturbations in development leading to CHD. Using a trisomy 21 (T21) sibling human embryonic stem cell (hESC) model of DS, we show that T21-hESC display many significant differences in expression of genes and cell populations associated with mesodermal, and more notably, secondary heart field (SHF) development, in particular a reduced number of ISL1(+) progenitor cells. Furthermore, we provide evidence for two candidate genes located on chromosome 21, ETS2 and ERG, whose overexpression during cardiac commitment likely account for the disruption of SHF development, as revealed by downregulation or overexpression experiments. Additionally, we uncover an abnormal electrophysiological phenotype in functional T21 cardiomyocytes, a result further supported by mRNA expression data acquired using RNA-Seq. These data, in combination, revealed a cardiomyocyte-specific phenotype in T21 cardiomyocytes, likely due to the overexpression of genes such as RYR2, NCX, and L-type Ca(2+) channel. These results contribute to the understanding of the mechanisms involved in the development of CHD. Stem Cells 2015;33:1434-1446. © 2015 AlphaMed Press.

  8. Retinoic acid-independent expression of Meis2 during autopod patterning in the developing bat and mouse limb.

    Science.gov (United States)

    Mason, Mandy K; Hockman, Dorit; Curry, Lyle; Cunningham, Thomas J; Duester, Gregg; Logan, Malcolm; Jacobs, David S; Illing, Nicola

    2015-01-01

    The bat has strikingly divergent forelimbs (long digits supporting wing membranes) and hindlimbs (short, typically free digits) due to the distinct requirements of both aerial and terrestrial locomotion. During embryonic development, the morphology of the bat forelimb deviates dramatically from the mouse and chick, offering an alternative paradigm for identifying genes that play an important role in limb patterning. Using transcriptome analysis of developing Natal long-fingered bat (Miniopterus natalensis) fore- and hindlimbs, we demonstrate that the transcription factor Meis2 has a significantly higher expression in bat forelimb autopods compared to hindlimbs. Validation by reverse transcriptase and quantitative polymerase chain reaction (RT-qPCR) and whole mount in situ hybridisation shows that Meis2, conventionally known as a marker of the early proximal limb bud, is upregulated in the bat forelimb autopod from CS16. Meis2 expression is localised to the expanding interdigital webbing and the membranes linking the wing to the hindlimb and tail. In mice, Meis2 is also expressed in the interdigital region prior to tissue regression. This interdigital Meis2 expression is not activated by retinoic acid (RA) signalling as it is present in the retained interdigital tissue of Rdh10 (trex/trex) mice, which lack RA. Additionally, genes encoding RA-synthesising enzymes, Rdh10 and Aldh1a2, and the RA nuclear receptor Rarβ are robustly expressed in bat fore- and hindlimb interdigital tissues indicating that the mechanism that retains interdigital tissue in bats also occurs independently of RA signalling. Mammalian interdigital Meis2 expression, and upregulation in the interdigital webbing of bat wings, suggests an important role for Meis2 in autopod development. Interdigital Meis2 expression is RA-independent, and retention of interdigital webbing in bat wings is not due to the suppression of RA-induced cell death. Rather, RA signalling may play a role in the thinning

  9. First report of adelphophagy in flatworms during the embryonic development of the planarian Schmidtea mediterranea (Benazzi, Baguñà, Ballester, Puccinelli & Del Papa, 1975) (Platyhelminthes, Tricladida)

    NARCIS (Netherlands)

    Harrath, A.H.; Sluys, R.; Zghal, F.; Tekaya, S.

    2009-01-01

    This paper details the embryonic development of the triclad flatworm Schmidtea mediterranea and describes, for the first time in flatworms, the phenomenon of adelphophagy. Embryonic development, which takes 23 days at 18-20°C, basically corresponds with the developmental stages documented in other

  10. SMOC1 is essential for ocular and limb development in humans and mice.

    Science.gov (United States)

    Okada, Ippei; Hamanoue, Haruka; Terada, Koji; Tohma, Takaya; Megarbane, Andre; Chouery, Eliane; Abou-Ghoch, Joelle; Jalkh, Nadine; Cogulu, Ozgur; Ozkinay, Ferda; Horie, Kyoji; Takeda, Junji; Furuichi, Tatsuya; Ikegawa, Shiro; Nishiyama, Kiyomi; Miyatake, Satoko; Nishimura, Akira; Mizuguchi, Takeshi; Niikawa, Norio; Hirahara, Fumiki; Kaname, Tadashi; Yoshiura, Koh-Ichiro; Tsurusaki, Yoshinori; Doi, Hiroshi; Miyake, Noriko; Furukawa, Takahisa; Matsumoto, Naomichi; Saitsu, Hirotomo

    2011-01-07

    Microphthalmia with limb anomalies (MLA) is a rare autosomal-recessive disorder, presenting with anophthalmia or microphthalmia and hand and/or foot malformation. We mapped the MLA locus to 14q24 and successfully identified three homozygous (one nonsense and two splice site) mutations in the SPARC (secreted protein acidic and rich in cysteine)-related modular calcium binding 1 (SMOC1) in three families. Smoc1 is expressed in the developing optic stalk, ventral optic cup, and limbs of mouse embryos. Smoc1 null mice recapitulated MLA phenotypes, including aplasia or hypoplasia of optic nerves, hypoplastic fibula and bowed tibia, and syndactyly in limbs. A thinned and irregular ganglion cell layer and atrophy of the anteroventral part of the retina were also observed. Soft tissue syndactyly, resulting from inhibited apoptosis, was related to disturbed expression of genes involved in BMP signaling in the interdigital mesenchyme. Our findings indicate that SMOC1/Smoc1 is essential for ocular and limb development in both humans and mice.

  11. Prolactin modulates luteal activity in the short-nosed fruit bat, Cynopterus sphinx during delayed embryonic development.

    Science.gov (United States)

    Anuradha; Krishna, Amitabh

    2017-07-01

    The aim of this study was to evaluate the role of prolactin as a modulator of luteal steroidogenesis during the period of delayed embryonic development in Cynopterus sphinx. A marked decline in circulating prolactin levels was noted during the months of November through December coinciding with the period of decreased serum progesterone and delayed embryonic development. The seasonal changes in serum prolactin levels correlated positively with circulating progesterone (P) level, but inversely with circulating melatonin level during first pregnancy showing delayed development in Cynopterus sphinx. The results also showed decreased expression of prolactin receptor-short form (PRL-RS) both in the corpus luteum and in the utero-embryonic unit during the period of delayed embryonic development. Bats treated in vivo with prolactin during the period of delayed development showed significant increase in serum progesterone and estradiol levels together with significant increase in the expression of PRL-RS, luteinizing hormone receptor (LH-R), steroidogenic acute receptor protein (STAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) in the ovary. Prolactin stimulated ovarian angiogenesis (vascular endothelial growth factor) and cell survival (B-cell lymphoma 2) in vivo. Significant increases in ovarian progesterone production and the expression of prolactin-receptor, LH-R, STAR and 3β-HSD proteins were noted following the exposure of LH or prolactin in vitro during the delayed period. In conclusion, short-day associated increased melatonin level may be responsible for decreased prolactin release during November-December. The decline in prolactin level might play a role in suppressing P and estradiol-17β (E2) estradiol levels thereby causing delayed embryonic development in C. sphinx. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Development and embryonic pattern of body wall musculature in the crassiclitellate Eisenia andrei (Annelida, Clitellata).

    Science.gov (United States)

    Hunnekuhl, Vera S; Bergter, Annette; Purschke, Günter; Paululat, Achim

    2009-09-01

    During early development of Eisenia andrei (Crassiclitellata), a loose arrangement of primary circular and longitudinal muscles encloses the whole embryo. Circular muscles differentiate in an anterior-posterior progression creating a segmental pattern. Primary circular muscles emerge at the segmental borders while later in development the central part of each segment is filled with circular strands. Longitudinal muscles develop in an anterio-posterior manner as well, but by continuous lengthening. Muscle growth is not restricted by segmental boundaries. The development begins with one pair of prominent longitudinal muscles differentiating ventrally along the right and the left germ band. These first muscles provide a guiding structure for the parallel organization of the afterwards differentiating longitudinal musculature. Additional primary longitudinal muscles emerge and form, together with the initial circular muscles, the primary muscle grid of the embryo. During the following development, secondary longitudinal muscle strands develop and integrate themselves into the primary grid. Meanwhile the primary circular muscles split into thin strands in a ventral to dorsal progression. Thus, a fine structured mesh of circular and longitudinal muscles is generated. Compared to other "Oligochaeta", embryonic muscle patterns in E. andrei are adapted to the development of a lecithotrophic embryo. Nevertheless, two general characteristics of annelid muscle development become evident. The first is the segmental development of the circular muscles from a set of initial muscles situated at the segment borders. Second, there is a continuous development of primary longitudinal muscles starting at the anterior pole. At least one pair of main primary longitudinal strands is characteristic in Annelida. The space between all primary strands is filled with secondary longitudinal strands during further development. Copyright 2009 Wiley-Liss, Inc.

  13. Serial block face-scanning electron microscopy: a tool for studying embryonic development at the cell-matrix interface.

    Science.gov (United States)

    Starborg, Tobias; Kadler, Karl E

    2015-03-01

    Studies of gene regulation, signaling pathways, and stem cell biology are contributing greatly to our understanding of early embryonic vertebrate development. However, much less is known about the events during the latter half of embryonic development, when tissues comprising mostly extracellular matrix (ECM) are formed. The matrix extends far beyond the boundaries of individual cells and is refractory to study by conventional biochemical and molecular techniques; thus major gaps exist in our knowledge of the formation and three-dimensional (3D) organization of the dense tissues that form the bulk of adult vertebrates. Serial block face-scanning electron microscopy (SBF-SEM) has the ability to image volumes of tissue containing numerous cells at a resolution sufficient to study the organization of the ECM. Furthermore, whereas light microscopy was once relatively straightforward and electron microscopy was performed in specialist laboratories, the tables are turned; SBF-SEM is relatively straightforward and is becoming routine in high-end resolution studies of embryonic structures in vivo. In this review, we discuss the emergence of SBF-SEM as a tool for studying embryonic vertebrate development. © 2015 Wiley Periodicals, Inc.

  14. Adult mortality probability and nest predation rates explain parental effort in warming eggs with consequences for embryonic development time

    Science.gov (United States)

    Martin, Thomas E.; Oteyza, Juan C.; Boyce, Andy J.; Lloyd, Penn; Ton, Riccardo

    2015-01-01

    Parental behavior and effort vary extensively among species. Life-history theory suggests that age-specific mortality could cause this interspecific variation, but past tests have focused on fecundity as the measure of parental effort. Fecundity can cause costs of reproduction that confuse whether mortality is the cause or the consequence of parental effort. We focus on a trait, parental allocation of time and effort in warming embryos, that varies widely among species of diverse taxa and is not tied to fecundity. We conducted studies on songbirds of four continents and show that time spent warming eggs varies widely among species and latitudes and is not correlated with clutch size. Adult and offspring (nest) mortality explained most of the interspecific variation in time and effort that parents spend warming eggs, measured by average egg temperatures. Parental effort in warming eggs is important because embryonic temperature can influence embryonic development period and hence exposure time to predation risk. We show through correlative evidence and experimental swapping of embryos between species that parentally induced egg temperatures cause interspecific variation in embryonic development period. The strong association of age-specific mortality with parental effort in warming eggs and the subsequent effects on embryonic development time are unique results that can advance understanding of broad geographic patterns of life-history variation.

  15. Research, design and development project Myoelectric Prosthesis of Upper Limb

    International Nuclear Information System (INIS)

    Galiano, L; Montaner, E; Flecha, A

    2007-01-01

    A Research Design and Development Project was developed of a myoelectric prosthesis for a pediatric patient presenting congenital amputation of the left forearm below the elbow. A multidisciplinary work-team was formed for this goal, in order to solve the several (/various) aspects regarding this project (mechanical, ergonomics, electronics, physical). The prosthesis as an electromechanical device was divided in several blocks, trying to achieve a focused development for each stage, acording to requisites. A mechanical prototype of the prothesis was designed and built along with the circuitry needed for EMG aquisition, control logic and drivers. Having acomplished the previuos stages, the project is now dealing with the definitions of the interface between the prosthesis and the patient, with promising perspectives

  16. Research, design and development project Myoelectric Prosthesis of Upper Limb

    Energy Technology Data Exchange (ETDEWEB)

    Galiano, L; Montaner, E; Flecha, A [Bioparx, J Hernandez 1101, Parana, ERios (Argentina)

    2007-11-15

    A Research Design and Development Project was developed of a myoelectric prosthesis for a pediatric patient presenting congenital amputation of the left forearm below the elbow. A multidisciplinary work-team was formed for this goal, in order to solve the several (/various) aspects regarding this project (mechanical, ergonomics, electronics, physical). The prosthesis as an electromechanical device was divided in several blocks, trying to achieve a focused development for each stage, acording to requisites. A mechanical prototype of the prothesis was designed and built along with the circuitry needed for EMG aquisition, control logic and drivers. Having acomplished the previuos stages, the project is now dealing with the definitions of the interface between the prosthesis and the patient, with promising perspectives.

  17. Bone characteristics of late-term embryonic and hatchling broilers: bone development under extreme growth rate.

    Science.gov (United States)

    Yair, R; Uni, Z; Shahar, R

    2012-10-01

    The development of broilers is an extreme example of rapid growth, increasing in weight from 40 g at hatch to 2,000 g 5 to 6 wk later. Such rapid growth requires a correspondingly fast development of the skeleton. Bone development is a genetically programmed process that is modified by epigenetic factors, mainly muscle-induced stresses and strains. In this study, we describe the temporal changes in bone morphology and material properties during the prehatch period [embryonic day (E) 14, E17, E19, E21] and posthatch d 3 and 7. The bones were examined for their weight, length, ash content, mechanical properties, and cortical structure. We show that the cross-sectional shape of the tibia and femur changes during the examination period from circular to elliptical. Additionally, the changes in bone properties are time-dependent and nonuniform: from E14 to E17 and from d 3 to 7, fast bone growth was noted, with major increases in both mechanical properties (stiffness, ultimate load, and energy to fracture) and geometric properties (cross-sectional area and thickness, medullary area, and moment of inertia). On the other hand, during the last days of incubation, most mechanical and geometric properties remain unchanged or even decrease. The reasons for this finding may relate to the hatching process but also to mineral shortage during the last days of incubation. This study leads to better understanding of bone development in ovo and posthatch in fast-growing broilers.

  18. Microgravity, stem cells, and embryonic development: challenges and opportunities for 3D tissue generation

    Science.gov (United States)

    Andreazzoli, Massimiliano; Angeloni, Debora; Broccoli, Vania; Demontis, Gian C.

    2017-04-01

    Space is a challenging environment for the human body, due to the combined effects of reduced gravity (microgravity) and cosmic radiation. Known effects of microgravity range from the blood redistribution that affects the cardiovascular system and the eye to muscle wasting, bone loss, anemia and immune depression. About cosmic radiation, the shielding provided by the spaceship hull is far less efficient than that afforded at ground level by the combined effects of the Earth atmosphere and magnetic field. The eye and its nervous layer (the retina) are affected by both microgravity and heavy ions exposure. Considering the importance of sight for long-term manned flights, visual research aimed at devising measures to protect the eye from environmental conditions of the outer space represents a special challenge to meet. In this review we focus on the impact of microgravity on embryonic development, discussing the roles of mechanical forces in the context of the neutral buoyancy the embryo experiences in the womb. At variance with its adverse effects on the adult human body, simulated microgravity may provide a unique tool for understanding the biomechanical events involved in the development and assembly in vitro of three-dimensional (3D) ocular tissues. Prospective benefits are the development of novel safety measures to protect the human eye from cosmic radiation in microgravity during long-term manned spaceflights in the outer space, as well as the generation of human 3D-retinas with its supporting structures to develop innovative and effective therapeutic options for degenerative eye diseases.

  19. Microgravity, Stem Cells, and Embryonic Development: Challenges and Opportunities for 3D Tissue Generation

    International Nuclear Information System (INIS)

    Andreazzoli, Massimiliano; Angeloni, Debora; Broccoli, Vania; Demontis, Gian C.

    2017-01-01

    Space is a challenging environment for the human body, due to the combined effects of reduced gravity (microgravity) and cosmic radiation. Known effects of microgravity range from the blood redistribution that affects the cardiovascular system and the eye to muscle wasting, bone loss, anemia, and immune depression. About cosmic radiation, the shielding provided by the spaceship hull is far less efficient than that afforded at ground level by the combined effects of the Earth atmosphere and magnetic field. The eye and its nervous layer (the retina) are affected by both microgravity and heavy ions exposure. Considering the importance of sight for long-term manned flights, visual research aimed at devising measures to protect the eye from environmental conditions of the outer space represents a special challenge to meet. In this review we focus on the impact of microgravity on embryonic development, discussing the roles of mechanical forces in the context of the neutral buoyancy the embryo experiences in the womb. At variance with its adverse effects on the adult human body, simulated microgravity may provide a unique tool for understanding the biomechanical events involved in the development and assembly in vitro of three-dimensional (3D) ocular tissues. Prospective benefits are the development of novel safety measures to protect the human eye from cosmic radiation in microgravity during long-term manned spaceflights in the outer space, as well as the generation of human 3D-retinas with its supporting structures to develop innovative and effective therapeutic options for degenerative eye diseases.

  20. Microgravity, Stem Cells, and Embryonic Development: Challenges and Opportunities for 3D Tissue Generation

    Energy Technology Data Exchange (ETDEWEB)

    Andreazzoli, Massimiliano [Department of Biology, University of Pisa, Pisa (Italy); Angeloni, Debora [Institute of Life Sciences, Scuola Superiore Sant' Anna, Pisa (Italy); Broccoli, Vania [National Research Council, Institute of Neuroscience, Milan (Italy); Stem Cells and Neurogenesis Unit, Division of Neuroscience, San Raffaele Scientific Institute, Milan (Italy); Demontis, Gian C., E-mail: giancarlo.demontis@farm.unipi.it [Department of Pharmacy and Centro D' Ateneo “E. Piaggio”, University of Pisa, Pisa (Italy)

    2017-04-25

    Space is a challenging environment for the human body, due to the combined effects of reduced gravity (microgravity) and cosmic radiation. Known effects of microgravity range from the blood redistribution that affects the cardiovascular system and the eye to muscle wasting, bone loss, anemia, and immune depression. About cosmic radiation, the shielding provided by the spaceship hull is far less efficient than that afforded at ground level by the combined effects of the Earth atmosphere and magnetic field. The eye and its nervous layer (the retina) are affected by both microgravity and heavy ions exposure. Considering the importance of sight for long-term manned flights, visual research aimed at devising measures to protect the eye from environmental conditions of the outer space represents a special challenge to meet. In this review we focus on the impact of microgravity on embryonic development, discussing the roles of mechanical forces in the context of the neutral buoyancy the embryo experiences in the womb. At variance with its adverse effects on the adult human body, simulated microgravity may provide a unique tool for understanding the biomechanical events involved in the development and assembly in vitro of three-dimensional (3D) ocular tissues. Prospective benefits are the development of novel safety measures to protect the human eye from cosmic radiation in microgravity during long-term manned spaceflights in the outer space, as well as the generation of human 3D-retinas with its supporting structures to develop innovative and effective therapeutic options for degenerative eye diseases.

  1. Nipbl and mediator cooperatively regulate gene expression to control limb development.

    Directory of Open Access Journals (Sweden)

    Akihiko Muto

    2014-09-01

    Full Text Available Haploinsufficiency for Nipbl, a cohesin loading protein, causes Cornelia de Lange Syndrome (CdLS, the most common "cohesinopathy". It has been proposed that the effects of Nipbl-haploinsufficiency result from disruption of long-range communication between DNA elements. Here we use zebrafish and mouse models of CdLS to examine how transcriptional changes caused by Nipbl deficiency give rise to limb defects, a common condition in individuals with CdLS. In the zebrafish pectoral fin (forelimb, knockdown of Nipbl expression led to size reductions and patterning defects that were preceded by dysregulated expression of key early limb development genes, including fgfs, shha, hand2 and multiple hox genes. In limb buds of Nipbl-haploinsufficient mice, transcriptome analysis revealed many similar gene expression changes, as well as altered expression of additional classes of genes that play roles in limb development. In both species, the pattern of dysregulation of hox-gene expression depended on genomic location within the Hox clusters. In view of studies suggesting that Nipbl colocalizes with the mediator complex, which facilitates enhancer-promoter communication, we also examined zebrafish deficient for the Med12 Mediator subunit, and found they resembled Nipbl-deficient fish in both morphology and gene expression. Moreover, combined partial reduction of both Nipbl and Med12 had a strongly synergistic effect, consistent with both molecules acting in a common pathway. In addition, three-dimensional fluorescent in situ hybridization revealed that Nipbl and Med12 are required to bring regions containing long-range enhancers into close proximity with the zebrafish hoxda cluster. These data demonstrate a crucial role for Nipbl in limb development, and support the view that its actions on multiple gene pathways result from its influence, together with Mediator, on regulation of long-range chromosomal interactions.

  2. Radiation-induced reduction of BMP-induced proteoglycan synthesis in an embryonal mesenchymal tissue equivalent using the chicken ''limb bud'' test

    International Nuclear Information System (INIS)

    Koelbl, O.; Pohl, F.; Flentje, M.; Knaus, P.; Sebald, W.

    2001-01-01

    Purpose: Heterotopic ossification (HO) is a common complication following total hip replacement. Clinical studies showed the effectiveness of irradiation for prevention of heterotopic ossification. The mechanism of radiotherapy responsible for the reduction of heterotopic ossification is unclear. The purpose of this study was to find a suitable cell system, which can reproduce in-vitro data resulting from clinical in-vivo studies. The establishment of such a cell model allows detailed analyses of the mechanism of radiotherapy. Method: The chicken limb bud test was used as an in-vitro model. The cells acquired by the limb bud test were irradiated with different doses (0 Gy, 3 Gy, 7 Gy, 10 Gy, 20 Gy). Irradiation was set either 1 hour before, or 1 or 3 days after BMP-2 incubation. The synthesis of proteoglycans (PGS) upon treatment with bone morphogenetic protein (BMP)-2 was measured in cells incubated with BMP-2 for 4 days followed by 35 SO 4 2- labeling for 6 hours. Labeled proteoglycans were precipitated using Alcian blue and measured in a raytest radio-TLC analyzer. The incubation with BMP-2 was defined to correlate the in-vivo stimulus meaning the operation. Results: The proteoglycan synthesis was significantly reduced by irradiation 1 hour before or 1 day after BMP-2 incubation, if the dosage was at least 7 Gy. Higher doses than 7 Gy did not lead to lower proteoglycan levels. There was only a trend for a reduction of proteoglycan synthesis by 3 Gy irradiation, but no significant difference compared to the non-irradiated control. An irradiation 3 days after BMP-2 incubation had no effect on proteoglycan. Conclusion: A dose and time dependent effect of radiation on BMP-2-induced proteoglycan synthesis was observed. Therefore the results of clinical in-vivo studies were reproduced exactly by the limb bud test. We established an in-vitro cell model to analyze the mechanism of the prevention of heterotopic ossification by radiotherapy on cellular or sub

  3. Spatial distributions of AQP5 and AQP0 in embryonic and postnatal mouse lens development

    Science.gov (United States)

    Petrova, Rosica S.; Schey, Kevin L.; Donaldson, Paul J.; Grey, Angus C.

    2015-01-01

    The expression of the water channel protein aquaporin (AQP)-5 in adult rodent and human lenses was recently reported using immunohistochemistry, molecular biology, and mass spectrometry techniques, confirming a second transmembrane water channel that is present in lens fibre cells in addition to the abundant AQP0 protein. Interestingly, the sub-cellular distribution and level of post-translational modification of both proteins changes with fibre cell differentiation and location in the adult rodent lens. This study compares the sub-cellular distribution of AQP0 and AQP5 during embryonic and postnatal fibre cell development in the mouse lens to understand how the immunolabelling patterns for both AQPs observed in adult lens are first established. Immunohistochemistry was used to map the cellular and sub-cellular distribution of AQP5 and AQP0 throughout the lens in cryosections from adult (6 weeks to 8 months) and postnatal (0-2 weeks) mouse lenses and in sections from paraffin embedded mouse embryos (E10-E19). All sections were imaged by fluorescence confocal microscopy. Using antibodies directed against the C-terminus of each AQP, AQP5 was abundantly expressed early in development, being found in the cytoplasm of cells of the lens vesicle and surrounding tissues (E10), while AQP0 was detected later (E11), and only in the membranes of elongating primary fibre cells. During the course of subsequent embryonic and postnatal development the pattern of cytoplasmic AQP5 and membranous AQP0 labelling was maintained until postnatal day 6 (P6). From P6 AQP5 labelling became progressively more membranous initially in the lens nucleus and then later in all regions of the lens, while AQP0 labelling was abruptly lost in the lens nucleus due to C-terminal truncation. Our results show that the spatial distribution patterns of AQP0 and AQP5 observed in the adult lens are established during a narrow window of post natal development (P6-P15) that precedes eye opening and coincides

  4. Vitellocytes and vitellogenesis in cestodes in relation to embryonic development, egg production and life cycle.

    Science.gov (United States)

    Swiderski, Z; Xylander, W E

    2000-06-01

    Vitellocytes have two important functions in cestode embryogenesis: (1) formation of hard egg-shell (e.g. Pseudophyllidea) or a delicate capsule (e.g. Cyclophyllidea), and (2) supplying nutritive reserves for the developing embryos. During evolution any of these two functions can be reduced or intensified in different taxa depending on the type of their embryonic development, degree of ovoviviparity and life cycles. Within the Cestoda, there are three monozoic taxa with only one set of genital organs: Amphilinidea, Gyrocotylidea and Caryophyllidea. In these monozoic taxa and some polyzoic groups with well developed vitellaria (e.g. Pseudophyllidea, Trypanorhyncha) a single oocyte [=germocyte] and a large number of vitellocytes (up to 30) are enclosed within a thick, hardened egg-shell, forming a type of eggs typical for the basic pattern of Neodermata. Only one type of egg-shell enclosures, the so-called 'heterogeneous shell-globule vesicle' is common for the above mentioned cestode taxa. Each membrane-bounded vesicle of mature vitellocytes contains numerous electron-dense shell globules embedded in a translucent matrix. In free-living Neoophora and Monogenea there are two types of vesicles with dense granules; the second is considered to be proteinaceous reserve material. Within the Cestoda, the numbers of vitellocytes per germocyte are reduced in those taxa forming eggs of the 'Cyclophyllidean-type' (e.g. Cyclophyllidea, Tetraphyllidea, Pseudophyllidea). This is particularly evident in Cyclophyllidea; for example, in vitellocytes of Hymenolepis diminuta (Hymenolepididae) there are numerous vitelline granules of homogeneously electron-dense material; in Catenotaenia pusilla (Catenotaeniidae) there are three large, homogenous vitelline vesicles, while in Inermicapsifer madagascariensis (Anoplocephalidae) there is only one large vitelline vesicle, containing homogeneously electron-dense material, which occupies most of the vitelline cell volume. In this respect the

  5. Evidence for the involvement of the Gli gene family in embryonic mouse lung development.

    Science.gov (United States)

    Grindley, J C; Bellusci, S; Perkins, D; Hogan, B L

    1997-08-15

    Murine Gli, Gli2, and Gli3 are zinc finger genes related to Drosophila cubitus interuptus, a component of the hedgehog signal transduction pathway. In the embryonic lung, all three Gli genes are strongly expressed at the pseudoglandular stage, in distinct but overlapping domains of the mesoderm. Expression of Gli and Gli3, but not of Gli2, is subsequently downregulated at the canalicular stage, coincident with a decline in the expression of sonic hedgehog (Shh) and the hedgehog receptor gene, patched (Ptc). Overexpression of Shh in the lung results in increased levels of Ptc mRNA. Gli, but not Gli2, is also upregulated, suggesting a differential involvement of the Gli genes in the regulation of Ptc by SHH during lung development. Gli3 is not upregulated by Shh overexpression. However, its importance for lung development is shown by the finding that Gli3XtJ embryos, homozygous for a mutation involving a deletion of the Gli3 gene, have a stereotypic pattern of abnormalities in lung morphogenesis. The pulmonary defects in these embryos, consisting of localized shape changes and size reductions, correlate with normal Gli3 expression. Thus, our data indicate that one of the Gli genes, Gli3, is essential for normal lung development, and that another, Gli, can be placed downstream of Shh signaling in the lung.

  6. The Expression of Embryonic Liver Development Genes in Hepatitis C Induced Cirrhosis and Hepatocellular Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Behnke, Martha, E-mail: mbehnke@mcvh-vcu.edu [Transplant Program Administration, Virginia Commonwealth University Health System, 1200 E. Broad St., Richmond, VA 23298 (United States); Reimers, Mark [Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University School of Medicine, 800 E Leigh St., Richmond, VA 23298 (United States); Fisher, Robert [Department of Surgery, Virginia Commonwealth University, 1200 E. Broad St., Richmond, VA 23298 (United States)

    2012-09-18

    Hepatocellular carcinoma (HCC) remains a difficult disease to study even after a decade of genomic analysis. Patient and disease heterogeneity, differences in statistical methods and multiple testing issues have resulted in a fragmented understanding of the molecular basis of tumor biology. Some researchers have suggested that HCC appears to share pathways with embryonic development. Therefore we generated targeted hypotheses regarding changes in developmental genes specific to the liver in HCV-cirrhosis and HCV-HCC. We obtained microarray studies from 30 patients with HCV-cirrhosis and 49 patients with HCV-HCC and compared to 12 normal livers. Genes specific to non-liver development have known associations with other cancer types but none were expressed in either adult liver or tumor tissue, while 98 of 179 (55%) genes specific to liver development had differential expression between normal and cirrhotic or HCC samples. We found genes from each developmental stage dysregulated in tumors compared to normal and cirrhotic samples. Although there was no single tumor marker, we identified a set of genes (Bone Morphogenetic Protein inhibitors GPC3, GREM1, FSTL3, and FST) in which at least one gene was over-expressed in 100% of the tumor samples. Only five genes were differentially expressed exclusively in late-stage tumors, indicating that while developmental genes appear to play a profound role in cirrhosis and malignant transformation, they play a limited role in late-stage HCC.

  7. Effects of heavy ion radiation on the brain vascular system and embryonic development

    Science.gov (United States)

    Yang, T. C.; Tobias, C. A.

    Using neonatal rats as a model system, we investigated the response of the brain vascular system to ionizing radiation and found that distinct petechial hemorrages developed in the cerebral cortex within a few hours after irradiation, reached a maximum about 13 to 24 hours, and decreased exponentially with time. No brain hemorrhage was found in neonatal rats 12 days after irradiation. Our experimental results indicate that a dose of a few hundred rad of X rays can induce a significant number of hemorrhages in the brain, and the number of lesions increases exponentially with dose. Heavy ions induce more hemorrhages than X rays for a given dose, and the RBE for 670 MeV/u neon particles ranges from about 2.0 for low doses to about 1.4 for high doses. A histological study on the hemorrhages indicates that a large number of red blood cells leak from the blood vessels. The radiation-induced hemorrhages may be a result of some capillary membrane damages or reproductive death of some blood vessel epithelial cells. The fast onset of hemorrhage after irradiation suggests that some membrane damage may be involved. The effect of heavy-ion radiation on the embryonic development was studied with energetic iron particles. Pregnant mice were whole-body irradiated with 600 MeV/u iron particles on day 6 of gestation and were sacrificed 12 days after irradiation. Various physical abnormalities were observed, and embryos irradiated with 1 rad iron particles showed retardation of body development.

  8. The Expression of Embryonic Liver Development Genes in Hepatitis C Induced Cirrhosis and Hepatocellular Carcinoma

    International Nuclear Information System (INIS)

    Behnke, Martha; Reimers, Mark; Fisher, Robert

    2012-01-01

    Hepatocellular carcinoma (HCC) remains a difficult disease to study even after a decade of genomic analysis. Patient and disease heterogeneity, differences in statistical methods and multiple testing issues have resulted in a fragmented understanding of the molecular basis of tumor biology. Some researchers have suggested that HCC appears to share pathways with embryonic development. Therefore we generated targeted hypotheses regarding changes in developmental genes specific to the liver in HCV-cirrhosis and HCV-HCC. We obtained microarray studies from 30 patients with HCV-cirrhosis and 49 patients with HCV-HCC and compared to 12 normal livers. Genes specific to non-liver development have known associations with other cancer types but none were expressed in either adult liver or tumor tissue, while 98 of 179 (55%) genes specific to liver development had differential expression between normal and cirrhotic or HCC samples. We found genes from each developmental stage dysregulated in tumors compared to normal and cirrhotic samples. Although there was no single tumor marker, we identified a set of genes (Bone Morphogenetic Protein inhibitors GPC3, GREM1, FSTL3, and FST) in which at least one gene was over-expressed in 100% of the tumor samples. Only five genes were differentially expressed exclusively in late-stage tumors, indicating that while developmental genes appear to play a profound role in cirrhosis and malignant transformation, they play a limited role in late-stage HCC

  9. Loss of ATF2 function leads to cranial motoneuron degeneration during embryonic mouse development.

    Directory of Open Access Journals (Sweden)

    Julien Ackermann

    2011-04-01

    Full Text Available The AP-1 family transcription factor ATF2 is essential for development and tissue maintenance in mammals. In particular, ATF2 is highly expressed and activated in the brain and previous studies using mouse knockouts have confirmed its requirement in the cerebellum as well as in vestibular sense organs. Here we present the analysis of the requirement for ATF2 in CNS development in mouse embryos, specifically in the brainstem. We discovered that neuron-specific inactivation of ATF2 leads to significant loss of motoneurons of the hypoglossal, abducens and facial nuclei. While the generation of ATF2 mutant motoneurons appears normal during early development, they undergo caspase-dependent and independent cell death during later embryonic and foetal stages. The loss of these motoneurons correlates with increased levels of stress activated MAP kinases, JNK and p38, as well as aberrant accumulation of phosphorylated neurofilament proteins, NF-H and NF-M, known substrates for these kinases. This, together with other neuropathological phenotypes, including aberrant vacuolisation and lipid accumulation, indicates that deficiency in ATF2 leads to neurodegeneration of subsets of somatic and visceral motoneurons of the brainstem. It also confirms that ATF2 has a critical role in limiting the activities of stress kinases JNK and p38 which are potent inducers of cell death in the CNS.

  10. Development of Screening Method for an Frail Elderly by Measurement Quantitative Lower Limb Muscular Strength

    Science.gov (United States)

    Yamashita, Kazuhiko; Iwakami, Yumi; Imaizumi, Kazuya; Sato, Mitsuru; Nakajima, Sawako; Ino, Shuichi; Kawasumi, Masashi; Ifukube, Tohru

    Falling is one of the most serious problems for the elderly. The aim of this study was to develop a screening method for identifying factors that increase the risk of falling among the elderly, particularly with regard to lower limb muscular strength. Subjects were 48 elderly volunteers, including 25 classed as healthy and 23 classed as frail. All subjects underwent measurement of lower limb muscular strength via toe gap force and measurement of muscle strength of the hip joint adductor via knee gap force. In the frail group, toe gap force of the right foot was 20% lower than that in the healthy group; toe gap force of the left foot in the frail group was 23% lower than that in the healthy group, while knee gap force was 20% lower. Furthermore, we found that combining left toe gap force and knee gap force gave the highest odds ratio (6.05) with 82.6% sensitivity and 56.0% specificity when the toe gap force was 24 N and the knee gap force was 100 N. Thus, lower limb muscular strength can be used for simple and efficient screening, and approaches to prevent falls can be based on quantitative data such as lower limb muscular strength.

  11. Surviving a flood: effects of inundation period, temperature and embryonic development stage in locust eggs.

    Science.gov (United States)

    Woodman, J D

    2015-08-01

    The Australian plague locust, Chortoicetes terminifera (Walker), is an important agricultural pest and oviposits into compacted soil across vast semi-arid and arid regions prone to irregular heavy summer rainfall. This study aimed to quantify the effects of flooding (control, 7, 14, 21, 28 and 35 days) at different temperatures (15, 20 and 25°C) and embryonic development stages (25 and 75%) on egg viability, hatchling nymph body mass and survival to second-instar. Egg viability after flooding was dependent on temperature and flood duration. Eggs inundated at 15°C showed ≥53.5% survival regardless of flood duration and development stage compared with ≤29.6% for eggs at 25°C for ≥21 days early in development and ≥14 days late in development. Hatchling nymphs did not differ in body mass relative to temperature or flood duration, but weighed more from eggs inundated early in development rather than late. Survival to second-instar was ≤55.1% at 15 and 20°C when eggs were flooded for ≥28 days late in development, ≤35.6% at 25°C when flooded for ≥28 days early in development, and zero when flooded for ≥21 days late in development. These results suggest that prolonged flooding in summer and early autumn may cause very high egg mortality and first-instar nymph mortality of any survivors, but is likely to only ever affect a small proportion of the metapopulation. More common flash flooding for ≤14 days is unlikely to cause high mortality and have any direct effect on distribution and abundance.

  12. An evolutionarily conserved enhancer regulates Bmp4 expression in developing incisor and limb bud.

    Directory of Open Access Journals (Sweden)

    Dolrudee Jumlongras

    Full Text Available To elucidate the transcriptional regulation of Bmp4 expression during organogenesis, we used phylogenetic footprinting and transgenic reporter analyses to identify Bmp4 cis-regulatory modules (CRMs. These analyses identified a regulatory region located ∼46 kb upstream of the mouse Bmp4 transcription start site that had previously been shown to direct expression in lateral plate mesoderm. We refined this regulatory region to a 396-bp minimal enhancer, and show that it recapitulates features of endogenous Bmp4 expression in developing mandibular arch ectoderm and incisor epithelium during the initiation-stage of tooth development. In addition, this enhancer directs expression in the apical ectodermal ridge (AER of the developing limb and in anterior and posterior limb mesenchyme. Transcript profiling of E11.5 mouse incisor dental lamina, together with protein binding microarray (PBM analyses, allowed identification of a conserved DNA binding motif in the Bmp4 enhancer for Pitx homeoproteins, which are also expressed in the developing mandibular and incisor epithelium. In vitro electrophoretic mobility shift assays (EMSA and in vivo transgenic reporter mutational analyses revealed that this site supports Pitx binding and that the site is necessary to recapitulate aspects of endogenous Bmp4 expression in developing craniofacial and limb tissues. Finally, Pitx2 chromatin immunoprecipitation (ChIP demonstrated direct binding of Pitx2 to this Bmp4 enhancer site in a dental epithelial cell line. These results establish a direct molecular regulatory link between Pitx family members and Bmp4 gene expression in developing incisor epithelium.

  13. Evolutionary development of embryonic cerebrospinal fluid composition and regulation: an open research field with implications for brain development and function.

    Science.gov (United States)

    Bueno, David; Garcia-Fernàndez, Jordi

    2016-03-15

    Within the consolidated field of evolutionary development, there is emerging research on evolutionary aspects of central nervous system development and its implications for adult brain structure and function, including behaviour. The central nervous system is one of the most intriguing systems in complex metazoans, as it controls all body and mind functions. Its failure is responsible for a number of severe and largely incurable diseases, including neurological and neurodegenerative ones. Moreover, the evolution of the nervous system is thought to be a critical step in the adaptive radiation of vertebrates. Brain formation is initiated early during development. Most embryological, genetic and evolutionary studies have focused on brain neurogenesis and regionalisation, including the formation and function of organising centres, and the comparison of homolog gene expression and function among model organisms from different taxa. The architecture of the vertebrate brain primordium also reveals the existence of connected internal cavities, the cephalic vesicles, which in fetuses and adults become the ventricular system of the brain. During embryonic and fetal development, brain cavities and ventricles are filled with a complex, protein-rich fluid called cerebrospinal fluid (CSF). However, CSF has not been widely analysed from either an embryological or evolutionary perspective. Recently, it has been demonstrated in higher vertebrates that embryonic cerebrospinal fluid has key functions in delivering diffusible signals and nutrients to the developing brain, thus contributing to the proliferation, differentiation and survival of neural progenitor cells, and to the expansion and patterning of the brain. Moreover, it has been shown that the composition and homeostasis of CSF are tightly controlled in a time-dependent manner from the closure of the anterior neuropore, just before the initiation of primary neurogenesis, up to the formation of functional choroid plexuses. In

  14. Formation of the hindgut cuticular lining during embryonic development of Porcellio scaber (Crustacea, Isopoda

    Directory of Open Access Journals (Sweden)

    Polona Mrak

    2015-07-01

    Full Text Available The hindgut and foregut in terrestrial isopod crustaceans are ectodermal parts of the digestive system and are lined by cuticle, an apical extracellular matrix secreted by epithelial cells. Morphogenesis of the digestive system was reported in previous studies, but differentiation of the gut cuticle was not followed in detail. This study is focused on ultrastructural analyses of hindgut apical matrices and cuticle in selected intramarsupial developmental stages of the terrestrial isopod Porcellio scaber in comparison to adult animals to obtain data on the hindgut cuticular lining differentiation. Our results show that in late embryos of stages 16 and 18 the apical matrix in the hindgut consists of loose material overlaid by a thin intensely ruffled electron dense lamina facing the lumen. The ultrastructural resemblance to the embryonic epidermal matrices described in several arthropods suggests a common principle in chitinous matrix differentiation. The hindgut matrix in the prehatching embryo of stage 19 shows characteristics of the hindgut cuticle, specifically alignment to the apical epithelial surface and a prominent electron dense layer of epicuticle. In the preceding embryonic stage – stage 18 – an electron dense lamina, closely apposed to the apical cell membrane, is evident and is considered as the first epicuticle formation. In marsupial mancae the advanced features of the hindgut cuticle and epithelium are evident: a more prominent epicuticular layer, formation of cuticular spines and an extensive apical labyrinth. In comparison to the hindgut cuticle of adults, the hindgut cuticle of marsupial manca and in particular the electron dense epicuticular layer are much thinner and the difference between cuticle architecture in the anterior chamber and in the papillate region is not yet distinguishable. Differences from the hindgut cuticle in adults imply not fully developed structure and function of the hindgut cuticle in marsupial

  15. Formation of the hindgut cuticular lining during embryonic development of Porcellioscaber (Crustacea, Isopoda).

    Science.gov (United States)

    Mrak, Polona; Bogataj, Urban; Štrus, Jasna; Žnidaršič, Nada

    2015-01-01

    The hindgut and foregut in terrestrial isopod crustaceans are ectodermal parts of the digestive system and are lined by cuticle, an apical extracellular matrix secreted by epithelial cells. Morphogenesis of the digestive system was reported in previous studies, but differentiation of the gut cuticle was not followed in detail. This study is focused on ultrastructural analyses of hindgut apical matrices and cuticle in selected intramarsupial developmental stages of the terrestrial isopod Porcellioscaber in comparison to adult animals to obtain data on the hindgut cuticular lining differentiation. Our results show that in late embryos of stages 16 and 18 the apical matrix in the hindgut consists of loose material overlaid by a thin intensely ruffled electron dense lamina facing the lumen. The ultrastructural resemblance to the embryonic epidermal matrices described in several arthropods suggests a common principle in chitinous matrix differentiation. The hindgut matrix in the prehatching embryo of stage 19 shows characteristics of the hindgut cuticle, specifically alignment to the apical epithelial surface and a prominent electron dense layer of epicuticle. In the preceding embryonic stage - stage 18 - an electron dense lamina, closely apposed to the apical cell membrane, is evident and is considered as the first epicuticle formation. In marsupial mancae the advanced features of the hindgut cuticle and epithelium are evident: a more prominent epicuticular layer, formation of cuticular spines and an extensive apical labyrinth. In comparison to the hindgut cuticle of adults, the hindgut cuticle of marsupial manca and in particular the electron dense epicuticular layer are much thinner and the difference between cuticle architecture in the anterior chamber and in the papillate region is not yet distinguishable. Differences from the hindgut cuticle in adults imply not fully developed structure and function of the hindgut cuticle in marsupial manca, possibly related also

  16. Acetylsalicylic acid interferes with embryonic kidney growth and development by a prostaglandin-independent mechanism.

    Science.gov (United States)

    Welham, Simon J M; Sparrow, Alexander J; Gardner, David S; Elmes, Matthew J

    2017-01-06

    To evaluate the effects of the non-selective, non-steroidal anti-inflammatory drug (NSAID) acetylsalicylic acid (ASA), on ex vivo embryonic kidney growth and development. Pairs of fetal mouse kidneys at embryonic day 12.5 were cultured ex vivo in increasing concentrations of ASA (0.04-0.4 mg/mL) for up to 7 d. One organ from each pair was grown in control media and was used as the internal control for the experimental contralateral organ. In some experiments, organs were treated with ASA for 48 h and then transferred either to control media alone or control media containing 10 μmol/L prostaglandin E 2 (PGE 2 ) for a further 5 d. Fetal kidneys were additionally obtained from prostaglandin synthase 2 homozygous null or heterozygous (PTGS2 -/- and PTGS2 -/+ ) embryos and grown in culture. Kidney cross-sectional area was used to determine treatment effects on kidney growth. Whole-mount labelling to fluorescently detect laminin enabled crude determination of epithelial branching using confocal microscopy. Increasing ASA concentration (0.1, 0.2 and 0.4 mg/mL) significantly inhibited metanephric growth ( P < 0.05). After 7 d of culture, exposure to 0.2 mg/mL and 0.4 mg/mL reduced organ size to 53% and 23% of control organ size respectively ( P < 0.01). Addition of 10 μmol/L PGE 2 to culture media after exposure to 0.2 mg/mL ASA for 48 h resulted in a return of growth area to control levels. Application of control media alone after cessation of ASA exposure showed no benefit on kidney growth. Despite the apparent recovery of growth area with 10 μmol/L PGE 2 , no obvious renal tubular structures were formed. The number of epithelial tips generated after 48 h exposure to ASA was reduced by 40% (0.2 mg/mL; P < 0.05) and 47% (0.4 mg/mL; P < 0.01). Finally, growth of PTGS2 -/- and PTGS2 +/- kidneys in organ culture showed no differences, indicating that PTGS2 derived PGE 2 may at best have a minor role. ASA reduces early renal growth and development but the role of

  17. Golga5 is dispensable for mouse embryonic development and postnatal survival.

    Science.gov (United States)

    McGee, Lynessa J; Jiang, Alex L; Lan, Yu

    2017-07-01

    Golgins are a family of coiled-coil proteins located at the cytoplasmic surface of the Golgi apparatus and have been implicated in maintaining Golgi structural integrity through acting as tethering factors for retrograde vesicle transport. Whereas knockdown of several individual golgins in cultured cells caused Golgi fragmentation and disruption of vesicle trafficking, analysis of mutant mouse models lacking individual golgins have discovered tissue-specific developmental functions. Recently, homozygous loss of function of GOLGA2, of which previous in vitro studies suggested an essential role in maintenance of Golgi structure and in mitosis, has been associated with a neuromuscular disorder in human patients, which highlights the need for understanding the developmental roles of the golgins in vivo. We report here generation of Golga5-deficient mice using CRISPR/Cas9-mediated genome editing. Although knockdown studies in cultured cells have implicated Golga5 in maintenance of Golgi organization, we show that Golga5 is not required for mouse embryonic development, postnatal survival, or fertility. Moreover, whereas Golga5 is structurally closely related to Golgb1, we show that inactivation of Golga5 does not enhance the severity of developmental defects in Golgb1-deficient mice. The Golga5-deficient mice enable further investigation of the roles and functional specificity of golgins in development and diseases. © 2017 Wiley Periodicals, Inc.

  18. Post-embryonic Hourglass Patterns Mark Ontogenetic Transitions in Plant Development.

    Science.gov (United States)

    Drost, Hajk-Georg; Bellstädt, Julia; Ó'Maoiléidigh, Diarmuid S; Silva, Anderson T; Gabel, Alexander; Weinholdt, Claus; Ryan, Patrick T; Dekkers, Bas J W; Bentsink, Leónie; Hilhorst, Henk W M; Ligterink, Wilco; Wellmer, Frank; Grosse, Ivo; Quint, Marcel

    2016-05-01

    The historic developmental hourglass concept depicts the convergence of animal embryos to a common form during the phylotypic period. Recently, it has been shown that a transcriptomic hourglass is associated with this morphological pattern, consistent with the idea of underlying selective constraints due to intense molecular interactions during body plan establishment. Although plants do not exhibit a morphological hourglass during embryogenesis, a transcriptomic hourglass has nevertheless been identified in the model plant Arabidopsis thaliana Here, we investigated whether plant hourglass patterns are also found postembryonically. We found that the two main phase changes during the life cycle of Arabidopsis, from embryonic to vegetative and from vegetative to reproductive development, are associated with transcriptomic hourglass patterns. In contrast, flower development, a process dominated by organ formation, is not. This suggests that plant hourglass patterns are decoupled from organogenesis and body plan establishment. Instead, they may reflect general transitions through organizational checkpoints. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  19. Genetic deletion of the EGFR ligand epigen does not affect mouse embryonic development and tissue homeostasis.

    Science.gov (United States)

    Dahlhoff, Maik; Schäfer, Matthias; Wolf, Eckhard; Schneider, Marlon R

    2013-02-15

    The epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor with manifold functions during development, tissue homeostasis and disease. EGFR activation, the formation of homodimers or heterodimers (with the related ERBB2-4 receptors) and downstream signaling is initiated by the binding of a family of structurally related growth factors, the EGFR ligands. Genetic deletion experiments clarified the biological function of all family members except for the last characterized ligand, epigen. We employed gene targeting in mouse embryonic stem cells to generate mice lacking epigen expression. Loss of epigen did not affect mouse development, fertility, or organ physiology. Quantitative RT-PCR analysis revealed increased expression of betacellulin and EGF in a few organs of epigen-deficient mice, suggesting a functional compensation by these ligands. In conclusion, we completed the genetic analysis of EGFR ligands and show that epigen has non-essential functions or functions that can be compensated by other EGFR ligands during growth and tissue homeostasis. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Cep55 regulates embryonic growth and development by promoting Akt stability in zebrafish.

    Science.gov (United States)

    Jeffery, Jessie; Neyt, Christine; Moore, Wade; Paterson, Scott; Bower, Neil I; Chenevix-Trench, Georgia; Verkade, Heather; Hogan, Benjamin M; Khanna, Kum Kum

    2015-05-01

    CEP55 was initially described as a centrosome- and midbody-associated protein and a key mediator of cytokinesis. More recently, it has been implicated in PI3K/AKT pathway activation via an interaction with the catalytic subunit of PI3K. However, its role in embryonic development is unknown. Here we describe a cep55 nonsense mutant zebrafish with which we can study the in vivo physiologic role of Cep55. Homozygous mutants underwent extensive apoptosis by 24 hours postfertilization (hpf) concomitant with cell cycle defects, and heterozygous carriers were indistinguishable from their wild-type siblings. A similar phenotype was also observed in zebrafish injected with a cep55 morpholino, suggesting the mutant is a cep55 loss-of-function model. Further analysis revealed that Akt was destabilized in the homozygous mutants, which partially phenocopied Akt1 and Akt2 knockdown. Expression of either constitutively activated PIK3CA or AKT1 could partially rescue the homozygous mutants. Consistent with a role for Cep55 in regulation of Akt stability, treatment with proteasome inhibitor, MG132, partially rescued the homozygous mutants. Taken together, these results provide the first description of Cep55 in development and underline the importance of Cep55 in the regulation of Pi3k/Akt pathway and in particular Akt stability. © FASEB.

  1. [Epigenetic modifications in human spermatozoon and its potential role in embryonic development].

    Science.gov (United States)

    Shaoqin, Ge; Zhenghui, Zhao; Xueqian, Zhang; Yuan, Hao

    2014-05-01

    Spermatogenesis is a highly complex process involving mitotic cell division, meiosis and the process of spermiogenesis, during which unique and extensive chromatin and epigenetic modifications are remodeled to bring about specific epigenetic profiles for spermatozoa. Recent studies have shown that epigenetic modifications in mature spermatozoon play an important role in the developing embryo and its alterations in epigenetic patterns may increase the risk for fertilization failure, dysfunction of embryogenesis, preterm birth, low birthweight, congenital anomalies, perinatal mortality, and several other pregnancy-related complications seen at a higher frequency in babies conceived by in vitro fertilization (IVF). In this review, we assess the significance of epigenetic modifications (DNA methylation, histone retention and modification, RNAs and protamine) in mature spermatozoon and its potential role in embryonic development, and elucidate the relationship between altered epigenetic profile and associated diseases, providing basic information for preventing and treating male infertility, evaluating the epigenetic quality of sperm and reducing the risk of epigenetic diseases with babies conceived by assisted reproductive technology (ART).

  2. A genetic screen for mutations affecting embryonic development in medaka fish (Oryzias latipes).

    Science.gov (United States)

    Loosli, F; Köster, R W; Carl, M; Kühnlein, R; Henrich, T; Mücke, M; Krone, A; Wittbrodt, J

    2000-10-01

    In a pilot screen, we assayed the efficiency of ethylnitrosourea (ENU) as a chemical mutagen to induce mutations that lead to early embryonic and larval lethal phenotypes in the Japanese medaka fish, Oryzias latipes. ENU acts as a very efficient mutagen inducing mutations at high rates in germ cells. Three repeated treatments of male fish in 3 mM ENU for 1 h results in locus specific mutation rates of 1.1-1.95 x10(-3). Mutagenized males were outcrossed to wild type females and the F1 offspring was used to establish F2 families. F2 siblings were intercrossed and the F3 progeny was scored 24, 48 and 72 h after fertilization for morphological alterations affecting eye development. The presented mutant phenotypes were identified using morphological criteria and occur during early developmental stages of medaka. They are stably inherited in a Mendelian fashion. The high efficiency of ENU to induce mutations in this pilot screen indicates that chemical mutagenesis and screening for morphologically visible phenotypes in medaka fish allows the genetic analysis of specific aspects of vertebrate development complementing the screens performed in other vertebrate model systems.

  3. Characterizing Semaphorin-Mediated Effects on Sensory and Motor Axon Pathfinding and Connectivity During Embryonic Development.

    Science.gov (United States)

    Huettl, Rosa Eva; Huber, Andrea B

    2017-01-01

    How are precise connectivity to peripheral targets and corresponding sensory-motor networks established during developmental innervation of the vertebrate extremities? The formation of functional sensory-motor circuits requires highly appropriate temporal and spatial regulation of axon growth which is achieved through the combination of different molecular mechanisms such as communication between heterotypic fiber systems, axon-environment, or axon-glia interactions that ensure proper fasciculation and accurate pathfinding to distal targets. Family members of the class 3 semaphorins and their cognate receptors, the neuropilins, were shown to govern various events during wiring of central and peripheral circuits, with mice lacking Sema3-Npn signaling showing deficits in timing of growth, selective fasciculation, guidance fidelity, and coupling of sensory axon growth to motor axons at developmental time points. Given the accuracy with which these processes have to interact in a stepwise manner, deficiency of the smallest cog in the wheel may impact severely on the faithful establishment and functionality of peripheral circuitries, ultimately leading to behavioral impairments or even cause the death of the animal. Reliable quantitative analyses of sensory-motor fasciculation, extension, and guidance of axons to their cognate target muscles and the skin during development, but also assessment of physiological and behavioral consequences at adult age, are therefore a necessity to extend our understanding of the molecular mechanisms of peripheral circuit formation. In this chapter we provide a detailed methodology to characterize class 3 semaphorin-mediated effects on peripheral sensory and motor axon pathfinding and connectivity during embryonic development.

  4. MicroRNA-10 modulates Hox genes expression during Nile tilapia embryonic development.

    Science.gov (United States)

    Giusti, Juliana; Pinhal, Danillo; Moxon, Simon; Campos, Camila Lovaglio; Münsterberg, Andrea; Martins, Cesar

    2016-05-01

    Hox gene clusters encode a family of transcription factors that govern anterior-posterior axis patterning during embryogenesis in all bilaterian animals. The time and place of Hox gene expression are largely determined by the relative position of each gene within its cluster. Furthermore, Hox genes were shown to have their expression fine-tuned by regulatory microRNAs (miRNAs). However, the mechanisms of miRNA-mediated regulation of these transcription factors during fish early development remain largely unknown. Here we have profiled three highly expressed miR-10 family members of Nile tilapia at early embryonic development, determined their genomic organization as well as performed functional experiments for validation of target genes. Quantitative analysis during developmental stages showed miR-10 family expression negatively correlates with the expression of HoxA3a, HoxB3a and HoxD10a genes, as expected for bona fide miRNA-mRNA interactions. Moreover, luciferase assays demonstrated that HoxB3a and HoxD10a are targeted by miR-10b-5p. Overall, our data indicate that the miR-10 family directly regulates members of the Hox gene family during Nile tilapia embryogenesis. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Assessment of microplastic toxicity to embryonic development of the sea urchin Lytechinus variegatus (Echinodermata: Echinoidea).

    Science.gov (United States)

    Nobre, C R; Santana, M F M; Maluf, A; Cortez, F S; Cesar, A; Pereira, C D S; Turra, A

    2015-03-15

    Apart from the physiological impacts on marine organisms caused by ingesting microplastics, the toxicity caused by substances leaching from these particles into the environment requires investigation. To understand this potential risk, we evaluated the toxicity of virgin (raw) and beach-stranded plastic pellets to the development of embryos of Lytechinus variegatus, simulating transfers of chemical compounds to interstitial water and water column by assays of pellet-water interface and elutriate, respectively. Both assays showed that virgin pellets had toxic effects, increasing anomalous embryonic development by 58.1% and 66.5%, respectively. The toxicity of stranded pellets was lower than virgin pellets, and was observed only for pellet-water interface assay. These results show that (i) plastic pellets act as a vector of pollutants, especially for plastic additives found on virgin particles; and that (ii) the toxicity of leached chemicals from pellets depends on the exposure pathway and on the environmental compartment in which pellets accumulate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Partial loss-of-function alleles reveal a role for GNOM in auxin transport-related, post-embryonic development of Arabidopsis

    DEFF Research Database (Denmark)

    Geldner, Niko; Richter, Sandra; Vieten, Anne

    2004-01-01

    The Arabidopsis GNOM gene encodes an ARF GDP/GTP exchange factor involved in embryonic axis formation and polar localisation of the auxin efflux regulator PIN1. To examine whether GNOM also plays a role in post-embryonic development and to clarify its involvement in auxin transport, we have...

  7. Development and evaluation of the activities measure for upper limb amputees.

    Science.gov (United States)

    Resnik, Linda; Adams, Laurel; Borgia, Matthew; Delikat, Jemy; Disla, Roxanne; Ebner, Christopher; Walters, Lisa Smurr

    2013-03-01

    (1) To develop a measure of activities for adults with upper limb amputation: the Activities Measure for Upper Limb Amputees (AM-ULA); and (2) to conduct initial psychometric evaluation of the measure. This was a cohort study where the prototype measure was administered twice within 1 week. Tests were videotaped and graded by 2 independent raters. Interrater reliability, test-retest reliability, internal consistency, and minimal detectable change were estimated. Known group validity was examined using analyses of variance comparing scores of transradial, transhumeral, and shoulder level amputees. Convergent validity was examined by correlating AM-ULA scores with dexterity tests and self-reported function. Hospital outpatient. Subjects (N=52) with upper limb amputation. Not applicable. Not applicable. Intraclass correlation coefficients (ICCs) for test-retest reliability were .88 to .91. ICCs for interrater reliability were .84 to .89. Cronbach alphas were .89 to .91. The minimal detectable change at the 90% confidence interval was 3.7 points. Subjects with more distal levels of limb loss had better scores than those with more proximal levels (P<.01). The AM-ULA was moderately correlated with most dexterity tests and self-reported function. The AM-ULA is a new measure of activity performance for adults with upper limb amputation that considers task completion, speed, movement quality, skillfulness of prosthetic use, and independence in its rating system. It has good interrater reliability, test-retest reliability, and demonstrated known group validity. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  8. Bilateral Persistent Sciatic Arteries Complicated with Acute Left Lower Limb Ischemia

    OpenAIRE

    Hsuan-Yin Wu; Yu-Jen Yang; Chao-Han Lai; Jun-Neng Roan; Chwan-Yau Luo; Chung-Dann Kan

    2007-01-01

    Persistent sciatic artery (PSA) is a rare congenital malformation. In the early embryonic stage, the sciatic artery is the major blood supply for the lower limb bulb and is later replaced by the iliofemoral artery as the limb develops. Its failure to regress, sometimes associated with femoral arterial hypoplasia, and therefore becoming the dominant inflow to the lower extremity is called PSA. This anomaly is often associated with a higher rate of aneurysm formation or thromboembolic complicat...

  9. Glycogen and Glucose Metabolism Are Essential for Early Embryonic Development of the Red Flour Beetle Tribolium castaneum

    Science.gov (United States)

    Fraga, Amanda; Ribeiro, Lupis; Lobato, Mariana; Santos, Vitória; Silva, José Roberto; Gomes, Helga; da Cunha Moraes, Jorge Luiz; de Souza Menezes, Jackson

    2013-01-01

    Control of energy metabolism is an essential process for life. In insects, egg formation (oogenesis) and embryogenesis is dependent on stored molecules deposited by the mother or transcribed later by the zygote. In oviparous insects the egg becomes an isolated system after egg laying with all energy conversion taking place during embryogenesis. Previous studies in a few vector species showed a strong correlation of key morphogenetic events and changes in glucose metabolism. Here, we investigate glycogen and glucose metabolism in the red flour beetle Tribolium castaneum, an insect amenable to functional genomic studies. To examine the role of the key enzymes on glycogen and glucose regulation we cloned and analyzed the function of glycogen synthase kinase 3 (GSK-3) and hexokinase (HexA) genes during T. castaneum embryogenesis. Expression analysis via in situ hybridization shows that both genes are expressed only in the embryonic tissue, suggesting that embryonic and extra-embryonic cells display different metabolic activities. dsRNA adult female injection (parental RNAi) of both genes lead a reduction in egg laying and to embryonic lethality. Morphological analysis via DAPI stainings indicates that early development is impaired in Tc-GSK-3 and Tc-HexA1 RNAi embryos. Importantly, glycogen levels are upregulated after Tc-GSK-3 RNAi and glucose levels are upregulated after Tc-HexA1 RNAi, indicating that both genes control metabolism during embryogenesis and oogenesis, respectively. Altogether our results show that T. castaneum embryogenesis depends on the proper control of glucose and glycogen. PMID:23750237

  10. Development of a high-affinity GABA uptake system in embryonic amphibian spinal neurons.

    Science.gov (United States)

    Lamborghini, J E; Iles, A

    1985-11-01

    High-affinity uptake systems for amino acid neurotransmitter precursors have been highly correlated with the use of the particular amino acid or its derivative as a transmitter. We have found interneurons in the Xenopus embryo spinal cord which accumulate GABA by a high-affinity uptake system. They originate near the end of gastrulation and their ability to accumulate GABA first appears at the early tail bud stage. By position and appearance they are comparable to some of the embryonic interneurons described by A. Roberts and J. D. W. Clarke (1982, Phil. Trans. R. Soc. London Ser. B 296, 195-212). GABA-accumulating neurons also develop in dissociated cell cultures made from the presumptive spinal cord of neural plate stage Xenopus embryos. GABA accumulation in cultured neurons, as in cells in vivo, occurs via a high-affinity uptake system; GABA-accumulating cells have the same time of origin as the cells in vivo, and the ability to accumulate GABA in the population of cultured neurons appears at a time equivalent to that observed in intact sibling embryos. Thus it seems likely that the population of GABA-accumulating neurons developing in cell culture corresponds to the GABA-accumulating interneurons in vivo. The development of these neurons in dissociated cell cultures permits perturbation experiments that would be difficult to perform in vivo. We have examined the development of high-affinity GABA uptake in conditions that permit no electrical impulse activity in the cultures. The onset and extent of development of GABA accumulation in the neuronal population are normal under these conditions.

  11. The human placenta is a hematopoietic organ during the embryonic and fetal periods of development

    Science.gov (United States)

    Bárcena, Alicia; Kapidzic, Mirhan; Muench, Marcus O.; Gormley, Matthew; Scott, Marvin A.; Weier, Jingly F.; Ferlatte, Christy; Fisher, Susan J.

    2008-01-01

    We studied the potential role of the human placenta as a hematopoietic organ during embryonic and fetal development. Placental samples contained two cell populations—CD34++CD45low and CD34+CD45low—that were found in chorionic villi and in the chorioamniotic membrane. CD34++CD45low cells express many cell surface antigens found on multipotent primitive hematopoietic progenitors and hematopoietic stem cells. CD34++CD45low cells contained colony-forming units culture (CFU-C) with myeloid and erythroid potential in clonogenic in vitro assays, and they generated CD56+ natural killer cells and CD19+CD20+sIgM+ B cells in polyclonal liquid cultures. CD34+CD45low cells mostly comprised erythroid- and myeloid-committed progenitors, while CD34− cells lacked CFU-C. The placenta-derived precursors were fetal in origin, as demonstrated by FISH using repeat-sequence chromosome-specific probes for X and Y. The number of CD34++CD45low cells increased with gestational age, but their density (cells per gram of tissue) peaked at 5–8 wk, decreasing more than sevenfold at the onset of the fetal phase (9 wk of gestation). In addition to multipotent progenitors, the placenta contained myeloid- and erythroid-committed progenitors indicative of active in situ hematopoiesis. These data suggest that the human placenta is an important hematopoietic organ, raising the possibility of banking placental hematopoietic stem cells along with cord blood for transplantation. PMID:19073167

  12. The human placenta is a hematopoietic organ during the embryonic and fetal periods of development.

    Science.gov (United States)

    Bárcena, Alicia; Kapidzic, Mirhan; Muench, Marcus O; Gormley, Matthew; Scott, Marvin A; Weier, Jingly F; Ferlatte, Christy; Fisher, Susan J

    2009-03-01

    We studied the potential role of the human placenta as a hematopoietic organ during embryonic and fetal development. Placental samples contained two cell populations-CD34(++)CD45(low) and CD34(+)CD45(low)-that were found in chorionic villi and in the chorioamniotic membrane. CD34(++)CD45(low) cells express many cell surface antigens found on multipotent primitive hematopoietic progenitors and hematopoietic stem cells. CD34(++)CD45(low) cells contained colony-forming units culture (CFU-C) with myeloid and erythroid potential in clonogenic in vitro assays, and they generated CD56(+) natural killer cells and CD19(+)CD20(+)sIgM(+) B cells in polyclonal liquid cultures. CD34(+)CD45(low) cells mostly comprised erythroid- and myeloid-committed progenitors, while CD34(-) cells lacked CFU-C. The placenta-derived precursors were fetal in origin, as demonstrated by FISH using repeat-sequence chromosome-specific probes for X and Y. The number of CD34(++)CD45(low) cells increased with gestational age, but their density (cells per gram of tissue) peaked at 5-8 wk, decreasing more than sevenfold at the onset of the fetal phase (9 wk of gestation). In addition to multipotent progenitors, the placenta contained myeloid- and erythroid-committed progenitors indicative of active in situ hematopoiesis. These data suggest that the human placenta is an important hematopoietic organ, raising the possibility of banking placental hematopoietic stem cells along with cord blood for transplantation.

  13. The genome of Austrofundulus limnaeus offers insights into extreme vertebrate stress tolerance and embryonic development.

    Science.gov (United States)

    Wagner, Josiah T; Singh, Param Priya; Romney, Amie L; Riggs, Claire L; Minx, Patrick; Woll, Steven C; Roush, Jake; Warren, Wesley C; Brunet, Anne; Podrabsky, Jason E

    2018-02-20

    The annual killifish Austrofundulus limnaeus inhabits ephemeral ponds in northern Venezuela, South America, and is an emerging extremophile model for vertebrate diapause, stress tolerance, and evolution. Embryos of A. limnaeus regularly experience extended periods of desiccation and anoxia as a part of their natural history and have unique metabolic and developmental adaptations. Currently, there are limited genomic resources available for gene expression and evolutionary studies that can take advantage of A. limnaeus as a unique model system. We describe the first draft genome sequence of A. limnaeus. The genome was assembled de novo using a merged assembly strategy and was annotated using the NCBI Eukaryotic Annotation Pipeline. We show that the assembled genome has a high degree of completeness in genic regions that is on par with several other teleost genomes. Using RNA-seq and phylogenetic-based approaches, we identify several candidate genes that may be important for embryonic stress tolerance and post-diapause development in A. limnaeus. Several of these genes include heat shock proteins that have unique expression patterns in A. limnaeus embryos and at least one of these may be under positive selection. The A. limnaeus genome is the first South American annual killifish genome made publicly available. This genome will be a valuable resource for comparative genomics to determine the genetic and evolutionary mechanisms that support the unique biology of annual killifishes. In a broader context, this genome will be a valuable tool for exploring genome-environment interactions and their impacts on vertebrate physiology and evolution.

  14. Effects of Krenite? brush control agent (fosamine ammonium) on embryonic development in mallards and bobwhite

    Science.gov (United States)

    Hoffman, D.J.

    1988-01-01

    Fosamine ammonium (Krenite) is a highly water-soluble carbamoylphosphonate herbicide used to control woody brush. It has been reported to be teratogenic to avian embryos following spray application of the eggs. The embryotoxic and teratogenic potential of Krenite was examined in mallards (Anas platyrhynchos) and bobwhite (Colinus virginianus). At 96 h of development, eggs were briefly immersed in distilled water or in Krenite formulation in distilled water at concentrations of 1.5, 6.5, or 30% fosamine ammonium. At 6.5% active ingredient (a.i.), Krenite reduced hatching success in bobwhite and mallards to 85 and 33% of that in the distilled-water controls. At 30% a.i., Krenite caused 95 to 100% mortality in both species by the time of hatching. Early embryonic growth was impaired by 30% Krenite in both species. There was no evidence of teratogenesis of the axial skeleton, as reported previously in chickens and Japanese quail (Coturnix japonica). Most abnormal embryos had severe edema and some stunting. Mallard hatchlings from the 1.5 and 6.5% Krenite groups weighed significantly less than controls and had lower plasma alanine aminotransferase and aspartate aminotransferase activities, with elevated plasma glucose and cholesterol concentrations. Brain acetylcholinesterase activity was unaffected by Krenite in embryos and hatchlings.

  15. Contrasting roles for MyoD in organizing myogenic promoter structures during embryonic skeletal muscle development.

    Science.gov (United States)

    Cho, Ok Hyun; Mallappa, Chandrashekara; Hernández-Hernández, J Manuel; Rivera-Pérez, Jaime A; Imbalzano, Anthony N

    2015-01-01

    Among the complexities of skeletal muscle differentiation is a temporal distinction in the onset of expression of different lineage-specific genes. The lineage-determining factor MyoD is bound to myogenic genes at the onset of differentiation whether gene activation is immediate or delayed. How temporal regulation of differentiation-specific genes is established remains unclear. Using embryonic tissue, we addressed the molecular differences in the organization of the myogenin and muscle creatine kinase (MCK) gene promoters by examining regulatory factor binding as a function of both time and spatial organization during somitogenesis. At the myogenin promoter, binding of the homeodomain factor Pbx1 coincided with H3 hyperacetylation and was followed by binding of co-activators that modulate chromatin structure. MyoD and myogenin binding occurred subsequently, demonstrating that Pbx1 facilitates chromatin remodeling and modification before myogenic regulatory factor binding. At the same time, the MCK promoter was bound by HDAC2 and MyoD, and activating histone marks were largely absent. The association of HDAC2 and MyoD was confirmed by co-immunoprecipitation, proximity ligation assay (PLA), and sequential ChIP. MyoD differentially promotes activated and repressed chromatin structures at myogenic genes early after the onset of skeletal muscle differentiation in the developing mouse embryo. © 2014 Wiley Periodicals, Inc.

  16. Cadmium affects muscle type development and axon growth in zebrafish embryonic somitogenesis.

    Science.gov (United States)

    Hen Chow, Elly Suk; Cheng, Shuk Han

    2003-05-01

    We have previously reported that exposure to cadmium during zebrafish embryonic development caused morphological malformations of organs and ectopic expression of genes involved in regulating developmental process. One of the most common developmental defects observed was altered axial curvature resulting from defects in the myotomes of the somites. In this study, we investigated the mechanisms of cadmium-induced toxicity in zebrafish somitogenesis. We showed that the critical period of exposure was the gastrulation period, which actually preceded the formation of the first morphologically distinct somites. The somites thus formed lost the typical chevron V-shape and are packed disorderly. The myogenic lineage commitment of the axial mesodermal cells was not affected, as the myogenic regulatory transcription factors were expressed normally. There were, however, losses of fast and slow muscle fibers in the myotomes. The innervation of the muscle blocks by spinal motoneurons is an important process of the somitogenesis. Both primary and secondary motoneurons appear to form normally while the axon growth is affected in cadmium-treated embryos. The notochord, which is essential in the patterning of the somites and the central nervous system, showed abnormal morphological features and failed to extend to the tail region. Taken together, it appears that cadmium exposure led to abnormal somite patterning of the muscle fibers and defects in axonogenesis.

  17. Evidence for intron length conservation in a set of mammalian genes associated with embryonic development

    LENUS (Irish Health Repository)

    2011-10-05

    Abstract Background We carried out an analysis of intron length conservation across a diverse group of nineteen mammalian species. Motivated by recent research suggesting a role for time delays associated with intron transcription in gene expression oscillations required for early embryonic patterning, we searched for examples of genes that showed the most extreme conservation of total intron content in mammals. Results Gene sets annotated as being involved in pattern specification in the early embryo or containing the homeobox DNA-binding domain, were significantly enriched among genes with highly conserved intron content. We used ancestral sequences reconstructed with probabilistic models that account for insertion and deletion mutations to distinguish insertion and deletion events on lineages leading to human and mouse from their last common ancestor. Using a randomization procedure, we show that genes containing the homeobox domain show less change in intron content than expected, given the number of insertion and deletion events within their introns. Conclusions Our results suggest selection for gene expression precision or the existence of additional development-associated genes for which transcriptional delay is functionally significant.

  18. Identification of the proteome composition occurring during the course of embryonic development of bees (Apis mellifera).

    Science.gov (United States)

    Li, J; Zhang, L; Feng, M; Zhang, Z; Pan, Y

    2009-02-01

    To investigate the proteome during embryonic development of honeybees, Apis mellifera, proteins were identified by two-dimensional gel electrophoresis, mass spectrometry and protein engine identification tools that were applied to MASCOT and Xproteo search engines. 312, 320, 315 proteins were detected in 24, 48 and 72 h embryos. Thirty-eight highly abundant proteins were identified at the three time points by MS fingerprinting. All 21 proteins could be identified as products of annotated genes of the honeybee. Identified proteins included six proteins related to the metabolism of carbohydrates and energy production, six proteins belonging to the heat shock protein family, three cytoskeletal proteins, four proteins related to the antioxidant system of the embryo and two proteins related to growth regulation of the embryo. Quantitative proteomics was applied to analyze differences in amounts of these proteins during the three above mentioned developmental stages. Our data present an initial molecular picture of honeybee embryos, and will hopefully pave the way for future research on this animal.

  19. Residual morphogenetic competence in the proximal core region of stage 25 chick limbs: Zwilling's hypothesis revisited.

    Science.gov (United States)

    Paulsen, D F; Miller, J W; Bentley, P A; Donald, M R

    1986-06-01

    Morphogenetic competence (MC) exists in embryonic limb tissue once thought to have lost this property as a consequence of cytodifferentiation. By stage 25 of chick embryonic development, cells in the proximal core of the limb have committed to the cartilage phenotype and are producing their characteristic extracellular matrix. Recombinant limb-bud grafts constructed using isolated fragments of this tissue produce outgrowths with a limb-like skeletal pattern. Inclusion of proximal peripheral tissue in the grafts (with or without the polarizing tissue) inhibits outgrowth and skeletal morphogenesis, explaining the failure of earlier studies to reveal the MC of the proximal core (chondrogenic) cells. Since definitive chondroblasts express MC in more permissive surroundings, it appears that Zwilling's assertion, that the onset of cytodifferentiation causes the loss of MC, is an oversimplification and that complex tissue interactions are probably involved.

  20. Adverse effects of parental zinc deficiency on metal homeostasis and embryonic development in a zebrafish model.

    Science.gov (United States)

    Beaver, Laura M; Nkrumah-Elie, Yasmeen M; Truong, Lisa; Barton, Carrie L; Knecht, Andrea L; Gonnerman, Greg D; Wong, Carmen P; Tanguay, Robert L; Ho, Emily

    2017-05-01

    The high prevalence of zinc deficiency is a global public health concern, and suboptimal maternal zinc consumption has been associated with adverse effects ranging from impaired glucose tolerance to low birthweights. The mechanisms that contribute to altered development and poor health in zinc deficient offspring are not completely understood. To address this gap, we utilized the Danio rerio model and investigated the impact of dietary zinc deficiency on adults and their developing progeny. Zinc deficient adult fish were significantly smaller in size, and had decreases in learning and fitness. We hypothesized that parental zinc deficiency would have an impact on their offspring's mineral homeostasis and embryonic development. Results from mineral analysis showed that parental zinc deficiency caused their progeny to be zinc deficient. Furthermore, parental dietary zinc deficiency had adverse consequences for their offspring including a significant increase in mortality and decreased physical activity. Zinc deficient embryos had altered expression of genes that regulate metal homeostasis including several zinc transporters (ZnT8, ZnT9) and the metal-regulatory transcription factor 1 (MTF-1). Zinc deficiency was also associated with decreased expression of genes related to diabetes and pancreatic development in the embryo (Insa, Pax4, Pdx1). Decreased expression of DNA methyltransferases (Dnmt4, Dnmt6) was also found in zinc deficient offspring, which suggests that zinc deficiency in parents may cause altered epigenetic profiles for their progeny. These data should inform future studies regarding zinc deficiency and pregnancy and suggest that supplementation of zinc deficient mothers prior to pregnancy may be beneficial. Published by Elsevier Inc.

  1. Embryonic, Larval, and Early Juvenile Development of the Tropical Sea Urchin, Salmacis sphaeroides (Echinodermata: Echinoidea

    Directory of Open Access Journals (Sweden)

    M. Aminur Rahman

    2012-01-01

    Full Text Available Salmacis sphaeroides (Linnaeus, 1758 is one of the regular echinoids, occuring in the warm Indo-West Pacific, including Johor Straits, between Malaysia and Singapore. In order to investigate the developmental basis of morphological changes in embryos and larvae, we documented the ontogeny of S. sphaeroides in laboratory condition. Gametes were obtained from adult individuals by 0.5 M KCl injection into the coelomic cavity. Fertilization rate at limited sperm concentration (10−5 dilution was 96.6±1.4% and the resulting embryos were reared at 24°C. First cleavage (2-cell, 4-cell, 8-cell, 16-cell, 32-cell, and multicell (Morulla stages were achieved 01.12, 02.03, 02.28, 02.51, 03.12, and 03.32 h postfertilization. Ciliated blastulae with a mean length of 174.72±4.43 μm hatched 08.45 h after sperm entry. The gastrulae formed 16.15 h postfertilization and the archenteron elongated constantly while ectodermal red-pigmented cells migrated synchronously to the apical plate. Pluteus larva started to feed unicellular algae in 2 d, grew continuously, and finally attained metamorphic competence in 35 d after fertilization. Metamorphosis took approximately 1 h 30 min from attachment to the complete resorption of larval tissues and the development of complete juvenile structure with adult spines, extended tubefeet and well-developed pedicellaria, the whole event of which usually took place within 1 d postsettlement. This study represents the first successful investigation on embryonic, larval, and early juvenile development of S. sphaeroides. The findings would greatly be helpful towards the understanding of ontogeny and life-history strategies, which will facilitate us to develop the breeding, seed production, and culture techniques of sea urchins in captive condition.

  2. WNT regulation of embryonic development likely involves pathways independent of nuclear CTNNB1.

    Science.gov (United States)

    Tribulo, Paula; Moss, James I; Ozawa, Manabu; Jiang, Zongliang; Tian, Xiuchun Cindy; Hansen, Peter J

    2017-04-01

    The bovine was used to examine the potential for WNT signaling to affect the preimplantation embryo. Expression of seven key genes involved in canonical WNT signaling declined to a nadir at the morula or blastocyst stage. Expression of 80 genes associated with WNT signaling in the morula and inner cell mass (ICM) and trophectoderm (TE) of the blastocyst was also evaluated. Many genes associated with WNT signaling were characterized by low transcript abundance. Seven genes were different between ICM and TE, and all of them were overexpressed in TE as compared to ICM, including WNT6, FZD1, FZD7, LRP6, PORCN, APC and SFRP1 Immunoreactive CTNNB1 was localized primarily to the plasma membrane at all stages examined from the 2-cell to blastocyst stages of development. Strikingly, neither CTNNB1 nor non-phospho (i.e., active) CTNNB1 was observed in the nucleus of blastomeres at any stage of development even after the addition of WNT activators to culture. In contrast, CTNNB1 associated with the plasma membrane was increased by activators of WNT signaling. The planar cell polarity pathway (PCP) could be activated in the embryo as indicated by an experiment demonstrating an increase in phospho-JNK in the nucleus of blastocysts treated with the non-canonical WNT11. Furthermore, WNT11 improved development to the blastocyst stage. In conclusion, canonical WNT signaling is attenuated in the preimplantation bovine embryo but WNT can activate the PCP component JNK. Thus, regulation of embryonic development by WNT is likely to involve activation of pathways independent of nuclear actions of CTNNB1. © 2017 Society for Reproduction and Fertility.

  3. Retinoid-like compounds produced by phytoplankton affect embryonic development of Xenopus laevis.

    Science.gov (United States)

    Smutná, M; Priebojová, J; Večerková, J; Hilscherová, K

    2017-04-01

    Teratogenic effects, which were remarkably similar to those induced by retinoic acids, have been seen in wild frogs indicating possible source of retinoids in the environment. Recent studies indicate that some cyanobacterial species can contain teratogenic retinoic acids (RAs) and their analogues. Retinoids are known to regulate important processes such as differentiation, development, and embryogenesis. The study investigated the effects of exudates (extracellular compounds) of two cyanobacteria species with retinoic-like activity and one algae species on embryonic development of amphibians. The retinoid-like activity determined by in vitro reporter gene assay reached 528ng retinoid equivalents (REQ)/L and 1000ng REQ/L in exudates of Cylindrospermopsis raciborskii and Microcystis aeruginosa, respectively, while algal exudates showed no detectable activity. Total mean of retinoid-like copounds into exudate was 35.6ng ATRA/mil.cells for M.aeruginosa and 6.71ng ATRA/mil.cells for C.raciborskii, respectively. Toxicity tests with amphibian embryos up to 96h of development were carried out according to the standard guide for the Frog Embryo Teratogenesis Assay Xenopus. Lowest observed effect concentrations (LOEC) of malformations (2.5-2.6µg/L REQ) were two times lower than LOEC for ATRA (5µg/L). The exudates of both cyanobacteria were indeed provoking diverse teratogenic effects (e.g. tail, gut and eyes deformation) and interference with growth in frogs embryos, while such effects were not observed for the algae. Xenopus embryos were also exposed to all-trans retinoic acid (ATRA) in concentration range (1-40µg/L) equivalent to the REQs detected in cyanobacterial exudates. ATRA (10µg/L) caused similar teratogenic phenotypes at corresponding REQs as cyanobacterial exudates. The study confirms the ability of some species of cyanobacteria to produce retinoids naturally and excrete them directly into the environment at concentrations which might have adverse influence on

  4. Toxicological effects of the different substances in tobacco smoke on human embryonic development by a systems chemo-biology approach.

    Directory of Open Access Journals (Sweden)

    Bruno César Feltes

    Full Text Available The physiological and molecular effects of tobacco smoke in adult humans and the development of cancer have been well described. In contrast, how tobacco smoke affects embryonic development remains poorly understood. Morphological studies of the fetuses of smoking pregnant women have shown various physical deformities induced by constant fetal exposure to tobacco components, especially nicotine. In addition, nicotine exposure decreases fetal body weight and bone/cartilage growth in addition to decreasing cranial diameter and tibia length. Unfortunately, the molecular pathways leading to these morphological anomalies are not completely understood. In this study, we applied interactome data mining tools and small compound interaction networks to elucidate possible molecular pathways associated with the effects of tobacco smoke components during embryonic development in pregnant female smokers. Our analysis showed a relationship between nicotine and 50 additional harmful substances involved in a variety of biological process that can cause abnormal proliferation, impaired cell differentiation, and increased oxidative stress. We also describe how nicotine can negatively affect retinoic acid signaling and cell differentiation through inhibition of retinoic acid receptors. In addition, nicotine causes a stress reaction and/or a pro-inflammatory response that inhibits the agonistic action of retinoic acid. Moreover, we show that the effect of cigarette smoke on the developing fetus could represent systemic and aggressive impacts in the short term, causing malformations during certain stages of development. Our work provides the first approach describing how different tobacco constituents affect a broad range of biological process in human embryonic development.

  5. Limb Prosthetics

    Science.gov (United States)

    ... Catheter Insertion Additional Content Medical News Overview of Limb Prosthetics By James Baird, CPO, Director of Education, Hanger ... DOCTORS: Click here for the Professional Version Limb Prosthetics Overview of Limb Prosthetics Prosthetic Parts Options for Limb Prostheses Preparing ...

  6. Mouse zygotes respond to severe sperm DNA damage by delaying paternal DNA replication and embryonic development.

    Directory of Open Access Journals (Sweden)

    Joanna E Gawecka

    Full Text Available Mouse zygotes do not activate apoptosis in response to DNA damage. We previously reported a unique form of inducible sperm DNA damage termed sperm chromatin fragmentation (SCF. SCF mirrors some aspects of somatic cell apoptosis in that the DNA degradation is mediated by reversible double strand breaks caused by topoisomerase 2B (TOP2B followed by irreversible DNA degradation by a nuclease(s. Here, we created zygotes using spermatozoa induced to undergo SCF (SCF zygotes and tested how they responded to moderate and severe paternal DNA damage during the first cell cycle. We found that the TUNEL assay was not sensitive enough to identify the breaks caused by SCF in zygotes in either case. However, paternal pronuclei in both groups stained positively for γH2AX, a marker for DNA damage, at 5 hrs after fertilization, just before DNA synthesis, while the maternal pronuclei were negative. We also found that both pronuclei in SCF zygotes with moderate DNA damage replicated normally, but paternal pronuclei in the SCF zygotes with severe DNA damage delayed the initiation of DNA replication by up to 12 hrs even though the maternal pronuclei had no discernable delay. Chromosomal analysis of both groups confirmed that the paternal DNA was degraded after S-phase while the maternal pronuclei formed normal chromosomes. The DNA replication delay caused a marked retardation in progression to the 2-cell stage, and a large portion of the embryos arrested at the G2/M border, suggesting that this is an important checkpoint in zygotic development. Those embryos that progressed through the G2/M border died at later stages and none developed to the blastocyst stage. Our data demonstrate that the zygote responds to sperm DNA damage through a non-apoptotic mechanism that acts by slowing paternal DNA replication and ultimately leads to arrest in embryonic development.

  7. Embryonic stem cell-derived embryoid bodies development in collagen gels recapitulates sprouting angiogenesis.

    Science.gov (United States)

    Feraud, O; Cao, Y; Vittet, D

    2001-12-01

    The formation of new blood vessels proceeds by both vasculogenesis and angiogenesis. The development of models, which fully recapitulate spatio-temporal events involved during these processes, are crucial to fully understand their mechanisms of regulation. In vitro differentiation of murine embryonic stem (ES) cells has been shown to be a useful tool to investigate factors and genes potentially involved in vasculogenesis (Hirashima et al, 1999; Risau et al, 1988; Vittet et al, 1996; Wang et al, 1992; Wartenberg et al, 1998). We asked here whether this model system can also recapitulate angiogenesis, which may offer new means to study mechanisms involved in this process. ES-derived embryoid bodies (EBs) obtained after 11 days of differentiation, in which a primitive vascular network had formed, were then subcultured into a type I collagen matrix. In the presence of angiogenic growth factors, EBs rapidly developed branching pseudopods. Whole mount immunostainings with a PECAM antibody revealed that more than 75% EBs displayed, within a few days, a large number of endothelial outgrowths that can give tube-like structures with concomitant differentiation of alpha-smooth muscle actin positive cells, thus evoking sprouting angiogenesis. High expression levels of flk1 (VEGFR2), flt1 (VEGFR1), tie-1, and tie-2 are also found, indicating that budding endothelial cells displayed an angiogenic phenotype. The endothelial sprouting response was specifically induced by angiogenic factors with a major contribution of vascular endothelial growth factor (VEGF). Known angiostatic agents, such as platelet factor 4 (PF4), angiostatin, and endostatin inhibited the formation of endothelial sprouts induced by angiogenic factors. Moreover, consistent with the in vivo phenotype, VE-cadherin deficient EBs failed to develop angiogenesis in this model. ES cell differentiation can then recapitulate, in addition to vasculogenesis, the early stages of sprouting angiogenesis. This model system

  8. Maternal topoisomerase II alpha, not topoisomerase II beta, enables embryonic development of zebrafish top2a-/- mutants

    Directory of Open Access Journals (Sweden)

    Sapetto-Rebow Beata

    2011-11-01

    Full Text Available Abstract Background Genetic alterations in human topoisomerase II alpha (TOP2A are linked to cancer susceptibility. TOP2A decatenates chromosomes and thus is necessary for multiple aspects of cell division including DNA replication, chromosome condensation and segregation. Topoisomerase II alpha is also required for embryonic development in mammals, as mouse Top2a knockouts result in embryonic lethality as early as the 4-8 cell stage. The purpose of this study was to determine whether the extended developmental capability of zebrafish top2a mutants arises from maternal expression of top2a or compensation from its top2b paralogue. Results Here, we describe bloody minded (blm, a novel mutant of zebrafish top2a. In contrast to mouse Top2a nulls, zebrafish top2a mutants survive to larval stages (4-5 day post fertilization. Developmental analyses demonstrate abundant expression of maternal top2a but not top2b. Inhibition or poisoning of maternal topoisomerase II delays embryonic development by extending the cell cycle M-phase. Zygotic top2a and top2b are co-expressed in the zebrafish CNS, but endogenous or ectopic top2b RNA appear unable to prevent the blm phenotype. Conclusions We conclude that maternal top2a enables zebrafish development before the mid-zygotic transition (MZT and that zebrafish top2a and top2b are not functionally redundant during development after activation of the zygotic genome.

  9. Maternal topoisomerase II alpha, not topoisomerase II beta, enables embryonic development of zebrafish top2a-/- mutants

    LENUS (Irish Health Repository)

    Sapetto-Rebow, Beata

    2011-11-23

    Abstract Background Genetic alterations in human topoisomerase II alpha (TOP2A) are linked to cancer susceptibility. TOP2A decatenates chromosomes and thus is necessary for multiple aspects of cell division including DNA replication, chromosome condensation and segregation. Topoisomerase II alpha is also required for embryonic development in mammals, as mouse Top2a knockouts result in embryonic lethality as early as the 4-8 cell stage. The purpose of this study was to determine whether the extended developmental capability of zebrafish top2a mutants arises from maternal expression of top2a or compensation from its top2b paralogue. Results Here, we describe bloody minded (blm), a novel mutant of zebrafish top2a. In contrast to mouse Top2a nulls, zebrafish top2a mutants survive to larval stages (4-5 day post fertilization). Developmental analyses demonstrate abundant expression of maternal top2a but not top2b. Inhibition or poisoning of maternal topoisomerase II delays embryonic development by extending the cell cycle M-phase. Zygotic top2a and top2b are co-expressed in the zebrafish CNS, but endogenous or ectopic top2b RNA appear unable to prevent the blm phenotype. Conclusions We conclude that maternal top2a enables zebrafish development before the mid-zygotic transition (MZT) and that zebrafish top2a and top2b are not functionally redundant during development after activation of the zygotic genome.

  10. Membrane properties of chick semicircular canal hair cells in situ during embryonic development.

    Science.gov (United States)

    Masetto, S; Perin, P; Malusà, A; Zucca, G; Valli, P

    2000-05-01

    The electrophysiological properties of developing vestibular hair cells have been investigated in a chick crista slice preparation, from embryonic day 10 (E10) to E21 (when hatching would occur). Patch-clamp whole-cell experiments showed that different types of ion channels are sequentially expressed during development. An inward Ca(2+) current and a slow outward rectifying K(+) current (I(K(V))) are acquired first, at or before E10, followed by a rapid transient K(+) current (I(K(A))) at E12, and by a small Ca-dependent K(+) current (I(KCa)) at E14. Hair cell maturation then proceeds with the expression of hyperpolarization-activated currents: a slow I(h) appears first, around E16, followed by the fast inward rectifier I(K1) around E19. From the time of its first appearance, I(K(A)) is preferentially expressed in peripheral (zone 1) hair cells, whereas inward rectifying currents are preferentially expressed in intermediate (zone 2) and central (zone 3) hair cells. Each conductance conferred distinctive properties on hair cell voltage response. Starting from E15, some hair cells, preferentially located at the intermediate region, showed the amphora shape typical of type I hair cells. From E17 (a time when the afferent calyx is completed) these cells expressed I(K, L), the signature current of mature type I hair cells. Close to hatching, hair cell complements and regional organization of ion currents appeared similar to those reported for the mature avian crista. By the progressive acquisition of different types of inward and outward rectifying currents, hair cell repolarization after both positive- and negative-current injections is greatly strengthened and speeded up.

  11. Effects of copper and cadmium spiked-sediments on embryonic development of Japanese medaka (Oryzias latipes).

    Science.gov (United States)

    Barjhoux, Iris; Baudrimont, Magalie; Morin, Bénédicte; Landi, Laure; Gonzalez, Patrice; Cachot, Jérôme

    2012-05-01

    Because of their high capacity to accumulate contaminants such as persistent organic pollutants and heavy metals, aquatic sediments are considered as a long-term source of contamination for aquatic organisms. In compliance with the increasing interest both for sediment quality evaluation and the use of fish early life stage (ELS) toxicity assays, we proposed an embryo-larval test to evaluate embryotoxicity and genotoxicity of sediment-bound contaminants. Pre-blastula stage medaka (Oryzias latipes) embryos were exposed by static sediment contact to two model heavy metals (cadmium and copper) at environmental concentrations during the whole 10-day embryonic development. Lethal and sub-lethal effects were recorded in both embryos and larvae for 20 days post fertilisation (dpf) using several global toxicity and phenotypic endpoints. The comet assay was also performed on medaka prolarvae to evaluate genotoxic effects of the tested chemicals. Environmental concentrations of cadmium (Cd) and copper (Cu) did not affect embryo and larval survival. However, both heavy metals significantly induced morphological abnormalities, particularly spinal and cardiovascular deformities. Cd but not Cu induced tachycardia. Both heavy metals induced a significant increase in DNA damage at all tested concentrations. Resulting LOEC values for Cd and Cu corresponded to 1.9 and 8.5 μg/g d.w. sediment, respectively. Although metal bioavailability is probably lower for naturally contaminated sediments, the relatively low toxicity thresholds for both Cd and Cu raise the question of possible risk for fish embryos developing in direct contact to sediments. This study demonstrates the applicability, sensitivity and relevance of the Japanese medaka embryo-larval assay (MELA) to evaluate sediment hazardous potency at environmental concentrations of heavy metals. Copyright © 2012. Published by Elsevier Inc.

  12. Genetic interactions between Shox2 and Hox genes during the regional growth and development of the mouse limb.

    Science.gov (United States)

    Neufeld, Stanley J; Wang, Fan; Cobb, John

    2014-11-01

    The growth and development of the vertebrate limb relies on homeobox genes of the Hox and Shox families, with their independent mutation often giving dose-dependent effects. Here we investigate whether Shox2 and Hox genes function together during mouse limb development by modulating their relative dosage and examining the limb for nonadditive effects on growth. Using double mRNA fluorescence in situ hybridization (FISH) in single embryos, we first show that Shox2 and Hox genes have associated spatial expression dynamics, with Shox2 expression restricted to the proximal limb along with Hoxd9 and Hoxa11 expression, juxtaposing the distal expression of Hoxa13 and Hoxd13. By generating mice with all possible dosage combinations of mutant Shox2 alleles and HoxA/D cluster deletions, we then show that their coordinated proximal limb expression is critical to generate normally proportioned limb segments. These epistatic interactions tune limb length, where Shox2 underexpression enhances, and Shox2 overexpression suppresses, Hox-mutant phenotypes. Disruption of either Shox2 or Hox genes leads to a similar reduction in Runx2 expression in the developing humerus, suggesting their concerted action drives cartilage maturation during normal development. While we furthermore provide evidence that Hox gene function influences Shox2 expression, this regulation is limited in extent and is unlikely on its own to be a major explanation for their genetic interaction. Given the similar effect of human SHOX mutations on regional limb growth, Shox and Hox genes may generally function as genetic interaction partners during the growth and development of the proximal vertebrate limb. Copyright © 2014 by the Genetics Society of America.

  13. Effect of culture medium volume and embryo density on early mouse embryonic development: tracking the development of the individual embryo.

    Science.gov (United States)

    Dai, Shan-Jun; Xu, Chang-Long; Wang, Jeffrey; Sun, Ying-Pu; Chian, Ri-Cheng

    2012-07-01

    To determine the optimal volume or density of embryos for the well-of-the-well (WOW) system in order to track the development of individual embryos and to determine whether the WOW system can reverse the negative impact of culturing embryos singly. (1) Mouse embryos (groups of nine at the 2-cell stage) were cultured in 6.25 μl, 12.50 μl, 25.00 μl and 50.00 μl of droplets of culture medium under paraffin oil; (2) Groups of three, six, nine and twelve embryos at the 2-cell stage were cultured in 50 μl of droplet of culture medium under paraffin oil; (3) Groups of nine embryos at the 2-cell stage were cultured in 50 μl of droplet under paraffin oil with or without nine micro-wells made on the bottom of the Petri dish into each of which were placed one of the nine embryos (WOW system). Also single 2-cell stage embryos was cultured individually in 5.5 μl of droplet of culture medium under paraffin oil with or without a single micro-well made on the bottom of the Petri dish (WOW system for single culture). At the end of culture, the percentages of blastocyst development, hatching and hatched blastocysts were compared in each group. The blastocysts were fixed for differential staining. The blastocyst development was significantly higher (P WOW system. The blastocyst development was not improved when single embryo cultured individually in a micro-well was compared to single embryo cultured individually without micro-well. The total cell numbers of blastocysts were significantly higher in group embryo culture than single embryo culture regardless of whether the WOW system was used. In addition, the total cell numbers of blastocysts were significantly higher (P WOW system than without. Group embryo culture is superior to single embryo culture for blastocyst development. The WOW system with 50 μl of droplet of culture medium can be used to track the individual development of embryo cultured in groups while preserving good embryonic development. The reduced

  14. Reproduction and embryonic development in two species of squaliform sharks, Centrophorus granulosus and Etmopterus princeps: Evidence of matrotrophy?

    Science.gov (United States)

    Cotton, Charles F.; Dean Grubbs, R.; Dyb, Jan E.; Fossen, Inge; Musick, John A.

    2015-05-01

    Modes of reproduction and embryonic development vary greatly among the elasmobranchs, and prior studies have suggested that the energetic toll of embryogenesis in lecithotrophic species depletes embryonic organic matter by 20% or more. Matrotrophic species experience a lesser reduction or an increase in organic matter during embryogenesis. To investigate the maternal-embryonic nutritional relationship, we measured changes in organic matter from fertilization to near-parturition in embryos of Centrophorus granulosus and Etmopterus princeps. Embryos of C. granulosus experienced a reduction of 19.5% in organic matter, while E. princeps embryos experienced a reduction of 7.7% in organic matter over the course of embryonic development, suggesting some level of matrotrophy occurs, particularly for the latter species. Uterine villi were present in both species and developed concurrently with the embryos, increasing in length and thickness while becoming progressively vascularized. Embryos of C. granulosus were dissected to track the partitioning of water, organic matter, and inorganic matter to the liver, external yolk sac, internal yolk sac, digestive tract, and evicerated body throughout development. Mating was aseasonal for both species and spatially-mediated segregation by sex and maturity stage was observed. Ovarian cycles were concurrent for C. granulosus and consecutive for E. princeps. Size at maturity for C. granulosus was determined to be 111 cm TL for males and 143 cm TL for females, with an average fecundity of 5.3 embryos (range=4-7). Size at maturity for E. princeps was determined to be 56.5 cm TL for males and 61 cm TL for females north of the Azores and 54 cm TL for males and 69 cm TL for females near the Charlie Gibbs Fracture Zone. Average fecundity was 11.2 embryos (range=7-18) for this species. This is the first reporting of reproductive parameters for these two species, and the information provided will be valuable for informing stock assessment

  15. Temperature during the last week of incubation. I. Effects on hatching pattern and broiler chicken embryonic organ development

    NARCIS (Netherlands)

    Maatjens, C.M.; Roovert-Reijrink, van I.A.M.; Engel, B.; Pol, van der C.W.; Kemp, B.; Brand, van den H.

    2016-01-01

    We investigated the effects of an eggshell temperature (EST) of 35.6, 36.7, 37.8, and 38.9°C applied from d of incubation (E) 15, E17, and E19 on hatching pattern and embryonic organ development. A total of 2,850 first-grade eggs of a 43-week-old Ross 308 broiler breeder flock were incubated at an

  16. Release of Ecdysteroid-Phosphates from Egg Yolk Granules and Their Dephosphorylation during Early Embryonic Development in Silkworm, Bombyx mori

    OpenAIRE

    Yamada, Ryouichi; Yamahama, Yumi; Sonobe, Haruyuki

    2005-01-01

    Newly laid eggs of many insect species store maternal ecdysteroids as physiologically inactive phosphoric esters. In the silkworm Bombyx mori, we previously reported the presence of a specific enzyme, called ecdysteroid-phosphate phosphatase (EPPase), which catalyzes the dephosphorylation of ecdysteroid-phosphates to increase the amount of free ecdysteroids during early embryonic development. In this study, we demonstrated that (1) EPPase is found in the cytosol of yolk cells, (2) ecdysteroid...

  17. Proteomics reveals changes in hepatic proteins during chicken embryonic development: an alternative model to study human obesity

    OpenAIRE

    Peng, Mengling; Li, Shengnan; He, Qianian; Zhao, Jinlong; Li, Longlong; Ma, Haitian

    2018-01-01

    Background Chicken embryos are widely used as a model for studies of obesity; however, no detailed information is available about the dynamic changes of proteins during the regulation of adipose biology and metabolism. Thus, the present study used an isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic approach to identify the changes in protein abundance at different stages of chicken embryonic development. Results In this study, the abundances of 293 hepatic proteins...

  18. Caenorhabditis elegans OSM-11 signaling regulates SKN-1/Nrf during embryonic development and adult longevity and stress response.

    Science.gov (United States)

    Dresen, Arne; Finkbeiner, Sandra; Dottermusch, Matthias; Beume, Jan-Sebastian; Li, Yujie; Walz, Gerd; Neumann-Haefelin, Elke

    2015-04-01

    The Nrf family of transcription factors is critical for stress defense and detoxification. In Caenorhabditis elegans, the Nrf protein ortholog SKN-1 mediates this conserved stress response and promotes longevity. Moreover, SKN-1 is well known for its essential functions during C. elegans embryogenesis. SKN-1 is maternally deployed and initiates a signaling network specifying development of the endoderm and mesoderm. In this study, we identify the conserved Notch ligand OSM-11 as a novel regulator of SKN-1. We find that genetic inactivation of osm-11 re-establishes development of the pharynx and intestine in skn-1 deficient embryos and thereby rescues embryonic lethality associated with loss of skn-1 function. Inactivation of other DSL- and DOS-motif Notch ligands does not prevent skn-1 embryonic lethality. In addition, we show that inactivation of osm-11 in adult worms robustly enhances lifespan and promotes resistance to environmental stress. SKN-1 is required for increased longevity and heat and oxidative stress resistance but not hyperosmotic stress conferred by osm-11. OSM-11 prevents the nuclear accumulation of SKN-1 and represses the transcriptional activation of SKN-1 target genes for cellular detoxification. Our findings indicate that OSM-11 antagonizes SKN-1 during embryonic development and reveal a highly context-specific relationship between OSM-11 and SKN-1 in promoting stress resistance and longevity. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Development of an Ex-Situ Limb Perfusion System for a Rodent Model.

    Science.gov (United States)

    Gok, Emre; Alghanem, Fares; Moon, Ruth; Guy, Erin; Rojas-Pena, Alvaro; Bartlett, Robert H; Ozer, Kagan

    2018-03-26

    Ex-situ perfusion (ESP) is a promising method in preserving vascularized composite tissue allografts (VCAs) with potential to widen donor procurement to larger geographic areas. To optimize the method of preservation, we developed a small animal model to conduct biomolecular investigations. Twenty rat hind limbs (18.2 ± 1.3 g) were procured and connected to our custom-made ESP system. Perfusion pressure and flow parameters were measured with hourly blood gas analysis under near-normothermic (30-35˚C) conditions. Perfusate was prepared with swine hemoglobin (6-9 g/dL) and STEEN Solution. After 6 hours of perfusion, gastrocnemius muscles were evaluated for their histology and metabolomic profiling. Following 3 sets of experiments, perfusion was maintained at an average flow of 0.9 ± 0.24 mL/min and resulted in lactate levels of 3.78 ± 1.02 mmol/L. Metabolomic analysis revealed maintained cellular energy stores (total adenylates perfusion 0.698 ± 0.052 versus baseline 0.685 ± 0.091 umols/ug, p = 0.831), and histologic analysis revealed no evidence of barotrauma or myodegeneration. Rat hind limbs were viable after 6 hours of ESP on our miniaturized ESP system. This study is the first to document the ex-situ hind limb perfusion platform on a rodent model. These experimental findings have potential to guide future research to extend the viable duration of VCA preservation.

  20. Stepwise renal lineage differentiation of mouse embryonic stem cells tracing in vivo development

    Energy Technology Data Exchange (ETDEWEB)

    Nishikawa, Masaki, E-mail: masakiwestriver@gmail.com [Medical and Research Services, Greater Los Angeles Veterans Affairs Healthcare System at Sepulveda, North Hills, CA (United States); University of California at Los Angeles, David Geffen School of Medicine, Los Angeles, CA 91343 (United States); Yanagawa, Naomi [Medical and Research Services, Greater Los Angeles Veterans Affairs Healthcare System at Sepulveda, North Hills, CA (United States); University of California at Los Angeles, David Geffen School of Medicine, Los Angeles, CA 91343 (United States); Kojima, Nobuhiko [Institute of Industrial Science (IIS), University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505 (Japan); Yuri, Shunsuke; Hauser, Peter V.; Jo, Oak D.; Yanagawa, Norimoto [Medical and Research Services, Greater Los Angeles Veterans Affairs Healthcare System at Sepulveda, North Hills, CA (United States); University of California at Los Angeles, David Geffen School of Medicine, Los Angeles, CA 91343 (United States)

    2012-01-13

    Highlights: Black-Right-Pointing-Pointer We induced renal lineages from mESCs by following the in vivo developmental cues. Black-Right-Pointing-Pointer We induced nephrogenic intermediate mesoderm by stepwise addition of factors. Black-Right-Pointing-Pointer We induced two types of renal progenitor cells by reciprocal conditioned media. Black-Right-Pointing-Pointer We propose the potential role of CD24 for the enrichment of renal lineage cells. -- Abstract: The in vitro derivation of renal lineage progenitor cells is essential for renal cell therapy and regeneration. Despite extensive studies in the past, a protocol for renal lineage induction from embryonic stem cells remains unestablished. In this study, we aimed to induce renal lineages from mouse embryonic stem cells (mESC) by following in vivo developmental stages, i.e., the induction of mesoderm (Stage I), intermediate mesoderm (Stage II) and renal lineages (Stage III). For stage I induction, in accordance with known signaling pathways involved in mesoderm development in vivo, i.e., Nodal, bone morphogenic proteins (BMPs) and Wnt, we found that the sequential addition of three factors, i.e., Activin-A (A), a surrogate for Nodal signaling, during days 0-2, A plus BMP-4 (4) during days 2-4, and A4 plus lithium (L), a surrogate for Wnt signaling, during days 4-6, was most effective to induce the mesodermal marker, Brachyury. For stage II induction, the addition of retinoic acid (R) in the continuous presence of A4L during days 6-8 was most effective to induce nephrogenic intermediate mesodermal markers, such as Pax2 and Lim1. Under this condition, more than 30% of cells were stained positive for Pax2, and there was a concomitant decrease in the expression of non-mesodermal markers. For stage III induction, in resemblance to the reciprocal induction between ureteric bud (UB) and metanephric mesenchyme (MM) during kidney development, we found that the exposure to conditioned media derived from UB and MM cells was

  1. The impact of ZnO nanoparticle aggregates on the embryonic development of zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Xiaoshan; Zhang Xuezhi; Chen Yongsheng [Department of Civil and Environmental Engineering, Arizona State University, Tempe, AZ 85287 (United States); Wang Jiangxin; Chang Yung [School of Life Sciences, Center for Infectious Diseases and Vaccinology, Biodesign Institute, Arizona State University, Tempe, AZ 85287 (United States)], E-mail: yung.chang@asu.edu, E-mail: yschen@asu.edu

    2009-05-13

    With extensive use of metal oxide nanoparticles (NPs) in a variety of applications comes a higher potential of release into aquatic environments. NPs tend to form much larger aggregates in water, which are expected to settle down to the bottom of the water column and possibly get mixed with the sediments. However, little is known about the environmental impacts and biological effects of these aggregated NPs in the sediment column. In this study, we examined the sedimentation of nanoscale ZnO particles (nZnO) in zebrafish culture medium, and assessed the toxicity of settled nZnO aggregates on developing zebrafish embryos and larvae. Given the known dissolution of nZnO particles to release Zn{sup 2+}, we also assessed the toxic effect of soluble Zn{sup 2+} in this organism. We demonstrated that within 48 h, micron-sized nZnO aggregates were formed and settled out of the culture medium. These aggregates were found to exert dose-dependent toxicity to zebrafish embryos and larvae, reducing the hatching rate and causing pericardial edema. The observed toxicity of the nZnO aggregates was not likely a result solely of particle dissolution, as soluble Zn{sup 2+} alone caused much less toxicity to zebrafish embryos than nZnO. Instead, the combination of both nZnO and Zn{sup 2+} may contribute to the embryonic toxicity, possibly by increasing reactive oxidative species (ROS) and/or compromising the cellular oxidative stress response. Interestingly, we demonstrated that one type of formulated sediments could mitigate the toxicity of nZnO aggregates, highlighting a possible countermeasure to reduce the adverse impact of nZnO aggregates on the environment.

  2. The impact of ZnO nanoparticle aggregates on the embryonic development of zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Zhu Xiaoshan; Zhang Xuezhi; Chen Yongsheng; Wang Jiangxin; Chang Yung

    2009-01-01

    With extensive use of metal oxide nanoparticles (NPs) in a variety of applications comes a higher potential of release into aquatic environments. NPs tend to form much larger aggregates in water, which are expected to settle down to the bottom of the water column and possibly get mixed with the sediments. However, little is known about the environmental impacts and biological effects of these aggregated NPs in the sediment column. In this study, we examined the sedimentation of nanoscale ZnO particles (nZnO) in zebrafish culture medium, and assessed the toxicity of settled nZnO aggregates on developing zebrafish embryos and larvae. Given the known dissolution of nZnO particles to release Zn 2+ , we also assessed the toxic effect of soluble Zn 2+ in this organism. We demonstrated that within 48 h, micron-sized nZnO aggregates were formed and settled out of the culture medium. These aggregates were found to exert dose-dependent toxicity to zebrafish embryos and larvae, reducing the hatching rate and causing pericardial edema. The observed toxicity of the nZnO aggregates was not likely a result solely of particle dissolution, as soluble Zn 2+ alone caused much less toxicity to zebrafish embryos than nZnO. Instead, the combination of both nZnO and Zn 2+ may contribute to the embryonic toxicity, possibly by increasing reactive oxidative species (ROS) and/or compromising the cellular oxidative stress response. Interestingly, we demonstrated that one type of formulated sediments could mitigate the toxicity of nZnO aggregates, highlighting a possible countermeasure to reduce the adverse impact of nZnO aggregates on the environment.

  3. Venous-derived angioblasts generate organ-specific vessels during zebrafish embryonic development.

    Science.gov (United States)

    Hen, Gideon; Nicenboim, Julian; Mayseless, Oded; Asaf, Lihee; Shin, Masahiro; Busolin, Giorgia; Hofi, Roy; Almog, Gabriella; Tiso, Natascia; Lawson, Nathan D; Yaniv, Karina

    2015-12-15

    Formation and remodeling of vascular beds are complex processes orchestrated by multiple signaling pathways. Although it is well accepted that vessels of a particular organ display specific features that enable them to fulfill distinct functions, the embryonic origins of tissue-specific vessels and the molecular mechanisms regulating their formation are poorly understood. The subintestinal plexus of the zebrafish embryo comprises vessels that vascularize the gut, liver and pancreas and, as such, represents an ideal model in which to investigate the early steps of organ-specific vessel formation. Here, we show that both arterial and venous components of the subintestinal plexus originate from a pool of specialized angioblasts residing in the floor of the posterior cardinal vein (PCV). Using live imaging of zebrafish embryos, in combination with photoconvertable transgenic reporters, we demonstrate that these angioblasts undergo two phases of migration and differentiation. Initially, a subintestinal vein forms and expands ventrally through a Bone Morphogenetic Protein-dependent step of collective migration. Concomitantly, a Vascular Endothelial Growth Factor-dependent shift in the directionality of migration, coupled to the upregulation of arterial markers, is observed, which culminates with the generation of the supraintestinal artery. Together, our results establish the zebrafish subintestinal plexus as an advantageous model for the study of organ-specific vessel development and provide new insights into the molecular mechanisms controlling its formation. More broadly, our findings suggest that PCV-specialized angioblasts contribute not only to the formation of the early trunk vasculature, but also to the establishment of late-forming, tissue-specific vascular beds. © 2015. Published by The Company of Biologists Ltd.

  4. Real-time Visualization of Tissue Dynamics during Embryonic Development and Malignant Transformation

    Science.gov (United States)

    Yamada, Kenneth

    Tissues undergo dramatic changes in organization during embryonic development, as well as during cancer progression and invasion. Recent advances in microscopy now allow us to visualize and track directly the dynamic movements of tissues, their constituent cells, and cellular substructures. This behavior can now be visualized not only in regular tissue culture on flat surfaces (`2D' environments), but also in a variety of 3D environments that may provide physiological cues relevant to understanding dynamics within living organisms. Acquisition of imaging data using various microscopy modalities will provide rich opportunities for determining the roles of physical factors and for computational modeling of complex processes in living tissues. Direct visualization of real-time motility is providing insight into biology spanning multiple spatio-temporal scales. Many cells in our body are known to be in contact with connective tissue and other forms of extracellular matrix. They do so through microscopic cellular adhesions that bind to matrix proteins. In particular, fluorescence microscopy has revealed that cells dynamically probe and bend the matrix at the sites of cell adhesions, and that 3D matrix architecture, stiffness, and elasticity can each regulate migration of the cells. Conversely, cells remodel their local matrix as organs form or tumors invade. Cancer cells can invade tissues using microscopic protrusions that degrade the surrounding matrix; in this case, the local matrix protein concentration is more important for inducing the micro-invasive protrusions than stiffness. On the length scales of tissues, transiently high rates of individual cell movement appear to help establish organ architecture. In fact, isolated cells can self-organize to form tissue structures. In all of these cases, in-depth real-time visualization will ultimately provide the extensive data needed for computer modeling and for testing hypotheses in which physical forces interact

  5. Development of a multiplex PCR assay for characterization of embryonic stem cells.

    Science.gov (United States)

    Pal, Rajarshi; Mamidi, Murali Krishna; Das, Anjan Kumar; Rao, Mahendra; Bhonde, Ramesh

    2013-01-01

    Several molecular methods like real-time PCR (Q-PCR), expression sequence tag (EST) scan, microarray and microRNA analysis, and massively parallel signature sequencing (MPSS) have proved to be increasingly sensitive and efficient for monitoring human embryonic stem cell (hESC) differentiation. However, most of these high-throughput tests have a limited use due to high cost, extended turnaround time, and the involvement of highly specialized technical expertise. Hence, there is a need of rapid, cost-effective, robust, yet sensitive method for routine screening of hESCs. A critical requirement in hESC cultures is to maintain a uniform undifferentiated state and to determine their differentiation capacity by showing the expression of germ-layer-specific gene markers. To determine the modulation of gene expression in hESCs during propagation, expansion, and differentiation via embryoid body (EB) formation, we developed a simple, rapid, inexpensive, and definitive multimarker, semiquantitative multiplex RT-PCR (mxPCR) platform technology. Among the 15 gene primers tested, 4 were pluripotent markers comprising of set 1; and 3 lineage-specific markers from each ecto-, meso-, and endoderm layers were combined as sets 2, 3, and 4, respectively. In summary, this study was performed to characterize hESCs on a molecular level and to determine the quality and degree of variability among hESC and their early progenies (EB). This single-reaction mxPCR assay was flexible and, by selecting appropriate reporter genes, can be designed for characterization of different hESC lines during routine maintenance and directed differentiation.

  6. Cytotoxic assessment of silver nanoparticles in embryonic development and kidney tissue in pregnant mice

    Directory of Open Access Journals (Sweden)

    Bagher seyedalipour

    2015-10-01

    Full Text Available Background and Aim: Regarding the widespread use of silver nanoparticles in medecine and lack of a detailed study of toxicity effects of these particles on fetus, this study was carried out to investigate histopathological changes of the kidneys and also embryonic development following exposure to silver nanoparticles. Materials and Methods: In this experimental study, thirty five female NMRI mice were randomly divided into five equal groups i.e. one control group and four experimental groups. The experimental groups intraperitoneally (IP received silver nanoparticles at concentrations of 50, 100, 200 and 400 mg/ kg . .every other day. On the 17th day  of pregnancy, the mice were dissected and  their kidneys and embryos tissues were separated and stained with hematoxylin and eosin for histopathological examinations. .Finally, the obtained data was fed into SPSS software (V:16 using statistical tests including Kolmogrof-Smearnof, one-way variance analysis, Dante, Mann-Whitney and Kruskal-Wallis and P<0.05 was taken as the significant level. Results: Histopathological assessment of kidney tissue following IP administration of silver nanoparticle indicated pathological changes including congestion, necrosis, inflammatory cell infiltration, vacuolar degeneration compared to the control group. Our findings showed that silver nanoparticles during the gestation period affects fetal organogenesis, evolution of neural structure, liver lobulation and fetal growth retardation. Mean number of somites in groups receiving doses of 200 and 400 mg kg, . significantly reduced compared to the control group (P<0.05. Conclusion: The obtained results suggest that  passing of silver nanoparticles through placenta is possible and damage caused by the particles  could lead to the deformity or developmental retardation of the fetus.

  7. Expression of the cholinergic signal-transduction pathway components during embryonic rat heart development

    NARCIS (Netherlands)

    Franco, D.; Moorman, A. F.; Lamers, W. H.

    1997-01-01

    BACKGROUND: Previous studies showed that acetylcholinesterase (AChE) activity is present in the downstream (arterial) part of the embryonic chick and rat heart, but its functional significance was unclear. To establish whether other components of a cholinergic signal-transduction pathway are present

  8. Expression and action of transforming growth factor beta (TGFbeta1, TGFbeta2, and TGFbeta3) during embryonic rat testis development.

    Science.gov (United States)

    Cupp, A S; Kim, G; Skinner, M K

    1999-06-01

    The objective of the current study was to determine the role of transforming growth factor beta (TGFbeta) during seminiferous cord formation and embryonic testis development. The expression pattern of mRNA for TGFbeta isoforms was evaluated during testis development through a quantitative reverse transcription-polymerase chain reaction (QRT-PCR) procedure. Expression of mRNA for TGFbeta1 was highest at postnatal day 0 (P0) and P10. In contrast, TGFbeta2 was high at embryonic day 15 (E15), declined at E16, and showed a transient increase at P0 through P3 of testis development. Interestingly, expression of mRNA for TGFbeta3 was high during embryonic development and then declined after P3. Immunohistochemical localization of TGFbeta1 and TGFbeta2 demonstrated expression in Sertoli cells at E14 and in the seminiferous cords at P0. Selective interstitial cells expressed high concentrations of TGFbeta1 and TGFbeta2 in P0 testis. TGFbeta3 was expressed in selective cells at the junction of the E14 testis and mesonephros. The cells expressing TGFbeta3 in the testis appeared to be preperitubular cells that resided around the seminiferous cords. TGFbeta3 was localized to gonocytes in P0 testis. TGFbeta1 was found to have no influence on seminiferous cord formation in embryonic organ cultures of E13 testis. In contrast, growth of both E13 and E14 embryonic organ cultures was inhibited by TGFbeta1 and resulted in reduced testis size (40% of controls) with fewer cords present. A P0 testis cell culture and thymidine incorporation assay were used to directly examine the effects of recombinant TGFbeta1. TGFbeta1 alone had no influence on thymidine incorporation in P0 testis cell cultures when compared to controls. Interestingly, TGFbeta1 inhibited epidermal growth factor (EGF), and 10% calf serum stimulated P0 testis cell growth but not FSH-stimulated growth. Therefore, TGFbeta1 appears to inhibit testis growth in both the embryonic and early postnatal periods. The hormonal

  9. Development of a 3-D Rehabilitation System for Upper Limbs Using ER Actuators in a Nedo Project

    Science.gov (United States)

    Furusho, Junji; Koyanagi, Ken'ichi; Nakanishi, Kazuhiko; Ryu, Ushio; Takenaka, Shigekazu; Inoue, Akio; Domen, Kazuhisa; Miyakoshi, Koichi

    New training methods and exercises for upper limbs rehabilitation are made possible by application of robotics and virtual reality technology. The technologies can also make quantitative evaluations and enhance the qualitative effect of training. We have joined a project managed by NEDO (New Energy and Industrial Technology Development Organization as a semi-governmental organization under the Ministry of Economy, Trade and Industry of Japan) 5-year Project, "Rehabilitation System for the Upper Limbs and Lower Limbs", and developed a 3-DOF exercise machine for upper limbs (EMUL) using ER actuators. In this paper, we also present the development of software for motion exercise trainings and some results of clinical evaluation. Moreover, it is discussed how ER actuators ensure the mechanical safety.

  10. Embryonic development of a whirligig beetle, Dineutus mellyi, with special reference to external morphology (insecta: Coleoptera, Gyrinidae).

    Science.gov (United States)

    Komatsu, Shintaro; Kobayashi, Yukimasa

    2012-05-01

    The egg morphology and successive changes of developing embryos of the whirligig beetle, Dineutus mellyi (Adephaga: Gyrinidae) are described from observations based on light and scanning electron microscopy. The egg surface is characterized by minute conical projections covering the entire egg surface, a stalk-like micropylar projection at the anterior pole of the egg, and a longitudinal split line along which the chorion is cleaved during the middle embryonic stages. The germ band or embryo is formed on the ventral egg surface, and develops on the surface throughout the egg period; thus, the egg is a superficial type, as is the case in most coleopteran species. A pair of lateral tracheal gills (LTGs) of the first abdominal segment originates from appendage-like projections arising at the lateral side of pleuropodia, and the LTGs of the second to ninth abdominal segments are arranged in a row with that of the first segment. Therefore, LTGs are structures with serial homology. The paired dorsal tracheal gills (DTGs) of the ninth abdominal segment are formed on the regions just latero-dorsal to the LTGs of this segment. Regarding the pleuropodia as the structures being homologous with thoracic legs, neither the LTGs nor DTGs are homologous with thoracic legs, but originate in the more lateral region corresponding to the future pleura of the thoracic segments. The last (10th) abdominal segment in the larva is formed by the fusion of the embryonic 10th and 11th abdominal segments. Four terminal hooks at the end of the last abdominal segment originate from two pairs of swellings on the posterior end of the embryonic 11th abdominal segment. It is proposed that the terminal hooks possibly correspond to the claws of medially fused cerci of the embryonic 11th abdominal segment. Copyright © 2011 Wiley Periodicals, Inc.

  11. Parthenogenesis in unfertilized eggs of Coturnix chinensis, the Chinese painted quail, and the effect of egg clutch position on embryonic development.

    Science.gov (United States)

    Parker, H M; McDaniel, C D

    2009-04-01

    Parthenogenesis, embryonic development of an unfertilized egg, was studied for many years in turkeys. In fact, as many as 49% of unfertilized Beltsville Small White turkey eggs develop embryos. However, no research exists on parthenogenesis in quail. The Chinese painted quail is a close relative of the more common Japanese quail and, unlike turkeys or chickens, the small Chinese painted quail reaches sexual maturity rapidly, making it a great candidate for further research on parthenogenesis. Obviously, a better understanding of avian parthenogenesis should increase our knowledge of avian fertilization and early embryonic development. Therefore, we determined if unfertilized Chinese painted quail hens produce embryos. Second, we explored the possibility that position of the egg within the clutch influences parthenogenesis. When initial secondary sexual plumage was apparent at 4 wk of age, male chicks were separated from females to prevent fertilization. Hens were placed in individual cages near sexual maturity, at approximately 6 wk of age. Individual eggs were collected daily and labeled with hen number and date. Eggs were stored for 0 to 3 d at 20 degrees C before incubation at 37.5 degrees C. After 10 d of incubation, approximately 4,000 eggs from 300 laying hens were examined for embryonic development under a magnifying lamp. On average, 4.8% of the unfertilized eggs contained an abortive form of embryonic development consisting of undifferentiated cells and unorganized membranes. Approximately 27% of the laying hens produced at least 1 egg with parthenogenic development. However, about 10% (30) of these hens exhibited a predisposition for parthenogenesis by producing 2 or more unfertilized eggs with embryonic development. Twenty percent of the eggs from 2 hens produced embryonic development. Additionally, the first egg laid in a clutch was most likely to produce embryonic development, with a steady decline in the percentage of eggs with embryonic development

  12. Embryonic Lethality Due to Arrested Cardiac Development in Psip1/Hdgfrp2 Double-Deficient Mice.

    Directory of Open Access Journals (Sweden)

    Hao Wang

    Full Text Available Hepatoma-derived growth factor (HDGF related protein 2 (HRP2 and lens epithelium-derived growth factor (LEDGF/p75 are closely related members of the HRP2 protein family. LEDGF/p75 has been implicated in numerous human pathologies including cancer, autoimmunity, and infectious disease. Knockout of the Psip1 gene, which encodes for LEDGF/p75 and the shorter LEDGF/p52 isoform, was previously shown to cause perinatal lethality in mice. The function of HRP2 was by contrast largely unknown. To learn about the role of HRP2 in development, we knocked out the Hdgfrp2 gene, which encodes for HRP2, in both normal and Psip1 knockout mice. Hdgfrp2 knockout mice developed normally and were fertile. By contrast, the double deficient mice died at approximate embryonic day (E 13.5. Histological examination revealed ventricular septal defect (VSD associated with E14.5 double knockout embryos. To investigate the underlying molecular mechanism(s, RNA recovered from ventricular tissue was subjected to RNA-sequencing on the Illumina platform. Bioinformatic analysis revealed several genes and biological pathways that were significantly deregulated by the Psip1 knockout and/or Psip1/Hdgfrp2 double knockout. Among the dozen genes known to encode for LEDGF/p75 binding factors, only the expression of Nova1, which encodes an RNA splicing factor, was significantly deregulated by the knockouts. However the expression of other RNA splicing factors, including the LEDGF/p52-interacting protein ASF/SF2, was not significantly altered, indicating that deregulation of global RNA splicing was not a driving factor in the pathology of the VSD. Tumor growth factor (Tgf β-signaling, which plays a key role in cardiac morphogenesis during development, was the only pathway significantly deregulated by the double knockout as compared to control and Psip1 knockout samples. We accordingly speculate that deregulated Tgf-β signaling was a contributing factor to the VSD and prenatal lethality

  13. Prenatal arsenic exposure alters the programming of the glucocorticoid signaling system during embryonic development

    Science.gov (United States)

    Caldwell, Katharine E.; Labrecque, Matthew T.; Solomon, Benjamin R.; Ali, Abdulmehdi; Allan, Andrea M.

    2015-01-01

    The glucocorticoid system, which plays a critical role in a host of cellular functions including mood disorders and learning and memory, has been reported to be disrupted by arsenic. In previous work we have developed and characterized a prenatal moderate arsenic exposure (50 ppb) model and identified several deficits in learning and memory and mood disorders, as well as alterations within the glucocorticoid receptor signaling system in the adolescent mouse. In these present studies we assessed the effects of arsenic on the glucocorticoid receptor (GR) pathway in both the placenta and the fetal brain in response at two critical periods, embryonic days 14 and 18. The focus of these studies was on the 11β-hydroxysteroid dehydrogenase enzymes (11β-HSD1 and 11β-HSD2) which play a key role in glucorticoid synthesis, as well as the expression and set point of the GR negative feedback regulation. Negative feedback regulation is established early in development. At E14 we found arsenic exposure significantly decreased expression of both protein and message in brain of GR and the 11β-HSD1, while 11β-HSD2 enzyme protein levels were increased but mRNA levels were decreased in the brain. These changes in brain protein continued into the E18 time point, but mRNA levels were no longer significantly altered. Placental HSD11B2 mRNA was not altered by arsenic treatment but protein levels were elevated at E14. GR placental protein levels were decreased at E18 in the arsenic exposed condition. This suggests that arsenic exposure may alter GR expression levels as a consequence of a prolonged developmental imbalance between 11β-HSD1 and 11β-HSD2 protein expression despite decreased 11HSDB2 mRNA. The suppression of GR and the failure to turn down 11β-HSD2 protein expression during fetal development may lead to an altered set point for GR signaling throughout adulthood. To our knowledge, these studies are the first to demonstrate that gestational exposure to moderate levels of

  14. Glycogen and glucose metabolism are essential for early embryonic development of the red flour beetle Tribolium castaneum.

    Directory of Open Access Journals (Sweden)

    Amanda Fraga

    Full Text Available Control of energy metabolism is an essential process for life. In insects, egg formation (oogenesis and embryogenesis is dependent on stored molecules deposited by the mother or transcribed later by the zygote. In oviparous insects the egg becomes an isolated system after egg laying with all energy conversion taking place during embryogenesis. Previous studies in a few vector species showed a strong correlation of key morphogenetic events and changes in glucose metabolism. Here, we investigate glycogen and glucose metabolism in the red flour beetle Tribolium castaneum, an insect amenable to functional genomic studies. To examine the role of the key enzymes on glycogen and glucose regulation we cloned and analyzed the function of glycogen synthase kinase 3 (GSK-3 and hexokinase (HexA genes during T. castaneum embryogenesis. Expression analysis via in situ hybridization shows that both genes are expressed only in the embryonic tissue, suggesting that embryonic and extra-embryonic cells display different metabolic activities. dsRNA adult female injection (parental RNAi of both genes lead a reduction in egg laying and to embryonic lethality. Morphological analysis via DAPI stainings indicates that early development is impaired in Tc-GSK-3 and Tc-HexA1 RNAi embryos. Importantly, glycogen levels are upregulated after Tc-GSK-3 RNAi and glucose levels are upregulated after Tc-HexA1 RNAi, indicating that both genes control metabolism during embryogenesis and oogenesis, respectively. Altogether our results show that T. castaneum embryogenesis depends on the proper control of glucose and glycogen.

  15. PERKEMBANGAN EMBRIO dan LARVA IKAN PATIN NASUTUS (Pangasius Nasutus Bleeker, 1863) (Pangasiidae; Pisces) [Embryonic And Larval Development Of Patin Nasutus (Pangasius Nasutus Bleeker, 1863) (Pangasiidae; Pisces)

    OpenAIRE

    Iswanto, Bambang; Tahapari, Evi

    2013-01-01

    Patin nasutus (Pangasius nasutus Bleeker, 1863) (Pangasiidae; Pisces) is a potential pangasiid catfish species to be cultured in Indonesia.Many efforts has been done to explore the potency of P.nasutus for aquaculture purposes.However, basic knowledge is still very rare such as its embryonic and larval development.The present study aimed to understand the embryonic and larval development of P. nasutus resulted from induced spawning of P.nasutus brooders at Research Institute for Fish Breeding...

  16. Inhibition of platelet-derived growth factor actions in the embryonic testis influences normal cord development and morphology.

    Science.gov (United States)

    Uzumcu, Mehmet; Dirks, Kristen A; Skinner, Michael K

    2002-03-01

    Platelet-derived growth factors (PDGFs) are paracrine factors with roles in mesenchymal-epithelial interactions during normal and pathologic processes. Previously, PDGF and its receptor (PDGFR) have been shown to be present in perinatal, peripubertal, and adult rat testes. The role of PDGF in embryonic testicular cord formation is not known. The hypothesis tested is that PDGFs and PDGFRs are expressed during cord formation and that inhibition of their action influences normal cord formation during embryonic testis development. Embryonic Day (E) 13 gonadal organ cultures were used. Organs were cultured for 3 days and treated daily with vehicle or a PDGFR-specific tyrosine phosphorylation inhibitor (i.e., the tyrphostin AG1295 or AG1296). Vehicle-treated testes formed normal cords, whereas tyrphostin-treated testes formed "swollen cords," a phenomenon characterized by a significant decrease in the number of cords per testis area and increased cord diameter due to fusion of cords. Expression of PDGF and PDGFR in E13, E14, E16, Postnatal Day (P) 0, and P20 testes was examined. Messenger RNAs for PDGF-A and -B and PDGF alpha- and beta-receptors were expressed in isolated testes during all developmental periods examined. Immunoreactivity for PDGF was present throughout the testicular compartment at E14, restricted primarily to testicular cords at E16, and present in cells of the testicular cords with a stronger immunoreactivity in certain interstitial cell types of P0 testis. PDGFR beta-receptor immunoreactivity was primarily localized to the mesonephros of E14 organs and the testicular interstitium of E16 and P0 testes. Tyrphostins did not affect apoptotic cell number in the testis. PDGF had no effect on cell growth in P0 testis cultures. The results show that PDGFs and PDGFRs are expressed in embryonic testis during cord formation in a tissue-specific manner. Inhibition of PDGF actions does not inhibit cord formation but does alter normal cord development and

  17. Time-Series Interactions of Gene Expression, Vascular Growth and Hemodynamics during Early Embryonic Arterial Development.

    Science.gov (United States)

    Goktas, Selda; Uslu, Fazil E; Kowalski, William J; Ermek, Erhan; Keller, Bradley B; Pekkan, Kerem

    2016-01-01

    The role of hemodynamic forces within the embryo as biomechanical regulators for cardiovascular morphogenesis, growth, and remodeling is well supported through the experimental studies. Furthermore, clinical experience suggests that perturbed flow disrupts the normal vascular growth process as one etiology for congenital heart diseases (CHD) and for fetal adaptation to CHD. However, the relationships between hemodynamics, gene expression and embryonic vascular growth are poorly defined due to the lack of concurrent, sequential in vivo data. In this study, a long-term, time-lapse optical coherence tomography (OCT) imaging campaign was conducted to acquire simultaneous blood velocity, pulsatile micro-pressure and morphometric data for 3 consecutive early embryonic stages in the chick embryo. In conjunction with the in vivo growth and hemodynamics data, in vitro reverse transcription polymerase chain reaction (RT-PCR) analysis was performed to track changes in transcript expression relevant to histogenesis and remodeling of the embryonic arterial wall. Our non-invasive extended OCT imaging technique for the microstructural data showed continuous vessel growth. OCT data coupled with the PIV technique revealed significant but intermitted increases in wall shear stress (WSS) between first and second assigned stages and a noticeable decrease afterwards. Growth rate, however, did not vary significantly throughout the embryonic period. Among all the genes studied, only the MMP-2 and CASP-3 expression levels remained unchanged during the time course. Concurrent relationships were obtained among the transcriptional modulation of the genes, vascular growth and hemodynamics-related changes. Further studies are indicated to determine cause and effect relationships and reversibility between mechanical and molecular regulation of vasculogenesis.

  18. Time-Series Interactions of Gene Expression, Vascular Growth and Hemodynamics during Early Embryonic Arterial Development.

    Directory of Open Access Journals (Sweden)

    Selda Goktas

    Full Text Available The role of hemodynamic forces within the embryo as biomechanical regulators for cardiovascular morphogenesis, growth, and remodeling is well supported through the experimental studies. Furthermore, clinical experience suggests that perturbed flow disrupts the normal vascular growth process as one etiology for congenital heart diseases (CHD and for fetal adaptation to CHD. However, the relationships between hemodynamics, gene expression and embryonic vascular growth are poorly defined due to the lack of concurrent, sequential in vivo data. In this study, a long-term, time-lapse optical coherence tomography (OCT imaging campaign was conducted to acquire simultaneous blood velocity, pulsatile micro-pressure and morphometric data for 3 consecutive early embryonic stages in the chick embryo. In conjunction with the in vivo growth and hemodynamics data, in vitro reverse transcription polymerase chain reaction (RT-PCR analysis was performed to track changes in transcript expression relevant to histogenesis and remodeling of the embryonic arterial wall. Our non-invasive extended OCT imaging technique for the microstructural data showed continuous vessel growth. OCT data coupled with the PIV technique revealed significant but intermitted increases in wall shear stress (WSS between first and second assigned stages and a noticeable decrease afterwards. Growth rate, however, did not vary significantly throughout the embryonic period. Among all the genes studied, only the MMP-2 and CASP-3 expression levels remained unchanged during the time course. Concurrent relationships were obtained among the transcriptional modulation of the genes, vascular growth and hemodynamics-related changes. Further studies are indicated to determine cause and effect relationships and reversibility between mechanical and molecular regulation of vasculogenesis.

  19. Fibroblast growth factor receptor 2 (FGFR2) is required for corneal epithelial cell proliferation and differentiation during embryonic development.

    Science.gov (United States)

    Zhang, Jinglin; Upadhya, Dinesh; Lu, Lin; Reneker, Lixing W

    2015-01-01

    Fibroblast growth factors (FGFs) play important roles in many aspects of embryonic development. During eye development, the lens and corneal epithelium are derived from the same surface ectodermal tissue. FGF receptor (FGFR)-signaling is essential for lens cell differentiation and survival, but its role in corneal development has not been fully investigated. In this study, we examined the corneal defects in Fgfr2 conditional knockout mice in which Cre expression is activated at lens induction stage by Pax6 P0 promoter. The cornea in LeCre, Fgfr2(loxP/loxP) mice (referred as Fgfr2(CKO)) was analyzed to assess changes in cell proliferation, differentiation and survival. We found that Fgfr2(CKO) cornea was much thinner in epithelial and stromal layer when compared to WT cornea. At embryonic day 12.5-13.5 (E12.5-13.5) shortly after the lens vesicle detaches from the overlying surface ectoderm, cell proliferation (judged by labeling indices of Ki-67, BrdU and phospho-histone H3) was significantly reduced in corneal epithelium in Fgfr2(CKO) mice. At later stage, cell differentiation markers for corneal epithelium and underlying stromal mesenchyme, keratin-12 and keratocan respectively, were not expressed in Fgfr2(CKO) cornea. Furthermore, Pax6, a transcription factor essential for eye development, was not present in the Fgfr2(CKO) mutant corneal epithelial at E16.5 but was expressed normally at E12.5, suggesting that FGFR2-signaling is required for maintaining Pax6 expression in this tissue. Interestingly, the role of FGFR2 in corneal epithelial development is independent of ERK1/2-signaling. In contrast to the lens, FGFR2 is not required for cell survival in cornea. This study demonstrates for the first time that FGFR2 plays an essential role in controlling cell proliferation and differentiation, and maintaining Pax6 levels in corneal epithelium via ERK-independent pathways during embryonic development.

  20. Proteomics reveals changes in hepatic proteins during chicken embryonic development: an alternative model to study human obesity.

    Science.gov (United States)

    Peng, Mengling; Li, Shengnan; He, Qianian; Zhao, Jinlong; Li, Longlong; Ma, Haitian

    2018-01-08

    Chicken embryos are widely used as a model for studies of obesity; however, no detailed information is available about the dynamic changes of proteins during the regulation of adipose biology and metabolism. Thus, the present study used an isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic approach to identify the changes in protein abundance at different stages of chicken embryonic development. In this study, the abundances of 293 hepatic proteins in 19-day old of chicken embryos compared with 14-day old and 160 hepatic proteins at hatching compared with 19-day old embryos were significantly changed. Pathway analysis showed that fatty acid degradation (upregulated ACAA2, CPT1A, and ACOX1), protein folding (upregulated PDIs, CALR3, LMAN1, and UBQLN1) and gluconeogenesis (upregulated ACSS1, AKR1A1, ALDH3A2, ALDH7A1, and FBP2) were enhanced from embryonic day 14 (E14) to E19 of chicken embryo development. Analysis of the differentially abundant proteins indicated that glycolysis was not the main way to produce energy from E19 to hatching day during chicken embryo development. In addition, purine metabolism was enhanced, as deduced from increased IMPDH2, NT5C, PGM2, and XDH abundances, and the decrease of growth rate could be overcome by increasing the abundance of ribosomal proteins from E19 to the hatching day. The levels of certain proteins were coordinated with each other to regulate the changes in metabolic pathways to satisfy the requirement for growth and development at different stages of chicken embryo development. Importantly, ACAA2, CPT1A, and ACOX1 might be key factors to control fat deposition during chicken embryonic development. These results provided information showing that chicken is a useful model to further investigate the mechanism of obesity and insulin resistance in humans.

  1. Expression, function and regulation of Evi-1 during embryonic avian development

    Czech Academy of Sciences Publication Activity Database

    Celá, Petra; Moravcová Balková, Simona; Bryjová, Anna; Horáková, D.; Míšek, Ivan; Richman, J. M.; Buchtová, Marcela

    2013-01-01

    Roč. 13, č. 8 (2013), s. 343-353 ISSN 1567-133X R&D Projects: GA ČR GA304/09/0725 Institutional support: RVO:67985904 ; RVO:68081766 Keywords : ecotropical viral integration site 1 * chondrogenesis * siRNA * limb patterning Subject RIV: EA - Cell Biology; EG - Zoology (UBO-W) Impact factor: 1.356, year: 2013

  2. Development of a residuum/socket interface simulator for lower limb prosthetics.

    Science.gov (United States)

    McGrath, Michael Paul; Gao, Jianliang; Tang, Jinghua; Laszczak, Piotr; Jiang, Liudi; Bader, Dan; Moser, David; Zahedi, Saeed

    2017-03-01

    Mechanical coupling at the interface between lower limb residua and prosthetic sockets plays an important role in assessing socket fitting and tissue health. However, most research lab-based lower limb prosthetic simulators to-date have implemented a rigid socket coupling. This study describes the fabrication and implementation of a lower limb residuum/socket interface simulator, designed to reproduce the forces and moments present during the key loading phases of amputee walking. An artificial residuum made with model bones encased in silicone was used, mimicking the compliant mechanical loading of a real residuum/socket interface. A 6-degree-of-freedom load cell measured the overall kinetics, having previously been incorporated into an amputee's prosthesis to collect reference data. The developed simulator was compared to a setup where a rigid pylon replaced the artificial residuum. A maximum uniaxial load of 850 N was applied, comparable to the peak vertical ground reaction force component during amputee walking. Load cell outputs from both pylon and residuum setups were compared. During weight acceptance, when including the artificial residuum, compression decreased by 10%, while during push off, sagittal bending and anterior-posterior shear showed a 25% increase and 34% decrease, respectively. Such notable difference by including a compliant residuum further highlighted the need for such an interface simulator. Subsequently, the simulator was adjusted to produce key load cell outputs briefly aligning with those from amputee walking. Force sensing resistors were deployed at load bearing anatomic locations on the residuum/socket interface to measure pressures and were compared to those cited in the literature for similar locations. The development of such a novel simulator provides an objective adjunct, using commonly available mechanical test machines. It could potentially be used to provide further insight into socket design, fit and the complex load

  3. Gait and Lower Limb Observation of Paediatrics (GALLOP): development of a consensus based paediatric podiatry and physiotherapy standardised recording proforma.

    Science.gov (United States)

    Cranage, Simone; Banwell, Helen; Williams, Cylie M

    2016-01-01

    Paediatric gait and lower limb assessments are frequently undertaken in podiatry and physiotherapy clinical practice and this is a growing area of expertise within Australia. No concise paediatric standardised recording proforma exists to assist clinicians in clinical practice. The aim of this study was to develop a gait and lower limb standardised recording proforma guided by the literature and consensus, for assessment of the paediatric foot and lower limb in children aged 0-18 years. Expert Australian podiatrists and physiotherapists were invited to participate in a three round Delphi survey panel using the online Qualtrics(©) survey platform. The first round of the survey consisted of open-ended questions on paediatric gait and lower limb assessment developed from existing templates and a literature search of standardised lower limb assessment methods. Rounds two and three consisted of statements developed from the first round responses. Questions and statements were included in the final proforma if 70 % or more of the participants indicated consensus or agreement with the assessment method and if there was support within the literature for paediatric age-specific normative data with acceptable reliability of outcome measures. There were 17 of the 21 (81 %) participants who completed three rounds of the survey. Consensus was achieved for 41 statements in Round one, 54 statements achieved agreement in two subsequent rounds. Participants agreed on 95 statements relating to birth history, developmental history, hip measurement, rotation of the lower limb, ankle range of motion, foot posture, balance and gait. Assessments with acceptable validity and reliability were included within the final Gait and Lower Limb Observation of Paediatrics (GALLOP) proforma. The GALLOP proforma is a consensus based, systematic and standardised way to collect information and outcome measures in paediatric lower limb assessment. This standardised recording proforma will assist

  4. Sp6 and Sp8 Transcription Factors Control AER Formation and Dorsal-Ventral Patterning in Limb Development

    Science.gov (United States)

    Haro, Endika; Delgado, Irene; Junco, Marisa; Yamada, Yoshihiko; Mansouri, Ahmed; Oberg, Kerby C.; Ros, Marian A.

    2014-01-01

    The formation and maintenance of the apical ectodermal ridge (AER) is critical for the outgrowth and patterning of the vertebrate limb. The induction of the AER is a complex process that relies on integrated interactions among the Fgf, Wnt, and Bmp signaling pathways that operate within the ectoderm and between the ectoderm and the mesoderm of the early limb bud. The transcription factors Sp6 and Sp8 are expressed in the limb ectoderm and AER during limb development. Sp6 mutant mice display a mild syndactyly phenotype while Sp8 mutants exhibit severe limb truncations. Both mutants show defects in AER maturation and in dorsal-ventral patterning. To gain further insights into the role Sp6 and Sp8 play in limb development, we have produced mice lacking both Sp6 and Sp8 activity in the limb ectoderm. Remarkably, the elimination or significant reduction in Sp6;Sp8 gene dosage leads to tetra-amelia; initial budding occurs, but neither Fgf8 nor En1 are activated. Mutants bearing a single functional allele of Sp8 (Sp6−/−;Sp8+/−) exhibit a split-hand/foot malformation phenotype with double dorsal digit tips probably due to an irregular and immature AER that is not maintained in the center of the bud and on the abnormal expansion of Wnt7a expression to the ventral ectoderm. Our data are compatible with Sp6 and Sp8 working together and in a dose-dependent manner as indispensable mediators of Wnt/βcatenin and Bmp signaling in the limb ectoderm. We suggest that the function of these factors links proximal-distal and dorsal-ventral patterning. PMID:25166858

  5. Hemihypertrophy and a poorly differentiated embryonal rhabdomyosarcoma of the pelvis.

    Science.gov (United States)

    Samuel, D P; Tsokos, M; DeBaun, M R

    1999-01-01

    Asymmetry of the limbs (conventionally known as hemihypertrophy) is one of the overgrowth syndromes occurring sporadically in the general population at a frequency of approximately 1:86,000. Hemihypertrophy is also reported as part of the Beckwith-Wiedemann syndrome which has as its cardinal features omphalocele, macroglossia and gigantism with hypoglycemia, organomegaly, renal anomalies, hemihypertrophy, and embryonal tumors occurring less frequently. Various neoplasms are also associated with isolated hemihypertrophy. Wilms tumor, adrenocortical carcinoma, and hepatoblastoma are the most frequent. Rhabdomyosarcoma, neuroblastoma, phaeochromocytoma, and undifferentiated sarcoma of the lung are encountered only rarely. Loss of heterozygosity (LOH) of chromosome 11p15.5 is strongly associated with childhood embryonal tumors, particularly Wilms tumor, hepatoblastoma, and rhabdomyosarcoma. In this article, we describe an adolescent male with congenital asymmetry of the lower limbs who presented with a large poorly differentiated pelvic sarcoma. Conventional histologic, immunohistochemical, and ultrastructural studies of this tumor were insufficient for accurate subclassfication. However, positive staining for MyoD1 (a recently identified embryonically expressed marker of muscle differentiation) and LOH at the tyrosine hydroxylase locus of chromosome 11p15.5 by molecular analysis favored the diagnosis of embryonal rhabdomyosarcoma over an undifferentiated sarcoma. This case stresses the importance of pursuing clinical findings when they occur in conditions with an increased risk of developing cancer, which in this case was asymmetry of a limb. Also illustrated by this patient is the need for early consideration of molecular diagnostic tests where available, to refine an uncertain pathologic diagnosis that may ultimately have an impact on treatment and prognosis.

  6. Ca2+ signaling and early embryonic patterning during the blastula and gastrula periods of zebrafish and Xenopus development.

    Science.gov (United States)

    Webb, Sarah E; Miller, Andrew L

    2006-11-01

    It has been proposed that Ca(2+) signaling, in the form of pulses, waves and steady gradients, may play a crucial role in key pattern forming events during early vertebrate development [L.F. Jaffe, Organization of early development by calcium patterns, BioEssays 21 (1999) 657-667; M.J. Berridge, P. Lipp, M.D. Bootman, The versatility and universality of calcium signaling, Nat. Rev. Mol. Cell Biol. 1 (2000) 11-21; S.E. Webb, A.L. Miller, Calcium signalling during embryonic development, Nat. Rev. Mol. Cell Biol. 4 (2003) 539-551]. With reference to the embryos of zebrafish (Danio rerio) and the frog, Xenopus laevis, we review the Ca(2+) signals reported during the Blastula and Gastrula Periods. This developmental window encompasses the major pattern forming events of epiboly, involution, and convergent extension, which result in the establishment of the basic germ layers and body axes [C.B. Kimmel, W.W. Ballard, S.R. Kimmel, B. Ullmann, T.F. Schilling, Stages of embryonic development of the zebrafish, Dev. Dyn. 203 (1995) 253-310]. Data will be presented to support the suggestion that propagating waves (both long and short range) of Ca(2+) release, followed by sequestration, may play a crucial role in: (1) Coordinating cell movements during these pattern forming events and (2) Contributing to the establishment of the basic embryonic axes, as well as (3) Helping to define the morphological boundaries of specific tissue domains and embryonic structures, including future organ anlagen [E. Gilland, A.L. Miller, E. Karplus, R. Baker, S.E. Webb, Imaging of multicellular large-scale rhythmic calcium waves during zebrafish gastrulation, Proc. Natl. Acad. Sci. USA 96 (1999) 157-161; J.B. Wallingford, A.J. Ewald, R.M. Harland, S.E. Fraser, Calcium signaling during convergent extension in Xenopus, Curr. Biol. 11 (2001) 652-661]. The various potential targets of these Ca(2+) transients will also be discussed, as well as how they might integrate with other known pattern forming

  7. Synergistic Function of E2F7 and E2F8 is Essential for Cell Survival and Embryonic Development

    OpenAIRE

    Li, Jing; Ran, Cong; Li, Edward; Gordon, Faye; Comstock, Grant; Siddiqui, Hasan; Cleghorn, Whitney; Chen, Hui-zi; Kornacker, Karl; Pandit, Shusil K.; Khanizadeh, Mehrbod; Weinstein, Michael; Leone, Gustavo; de Bruin, Alain

    2008-01-01

    The novel E2f7 and E2f8 family members are thought to function as transcriptional repressors important for the control of cell proliferation. Here we have analyzed the consequences of inactivating E2f7 and E2f8 in mice and show that their individual loss had no significant effect on development. Their combined ablation, however, resulted in massive apoptosis and dilation of blood vessels, culminating in lethality by embryonic day E11.5. A deficiency in E2f7 and E2f8 led to an increase in E2f1...

  8. Embryonic development of chicken (Gallus Gallus Domesticus) from 1st to 19th day-ectodermal structures.

    Science.gov (United States)

    Toledo Fonseca, Erika; De Oliveira Silva, Fernanda Menezes; Alcântara, Dayane; Carvalho Cardoso, Rafael; Luís Franciolli, André; Sarmento, Carlos Alberto Palmeira; Fratini, Paula; José Piantino Ferreira, Antônio; Miglino, Maria Angélica

    2013-12-01

    Birds occupy a prominent place in the Brazilian economy not only in the poultry industry but also as an animal model in many areas of scientific research. Thus the aim of this study was to provide a description of macro and microscopic aspects of the ectoderm-derived structures in chicken embryos / fetuses poultry (Gallus gallus domesticus) from 1st to 19th day of incubation. 40 fertilized eggs, from a strain of domestic chickens, with an incubation period of 2-19 days were subjected to macroscopic description, biometrics, light, and scanning microscopy. All changes observed during the development were described. The nervous system, skin and appendages and organs related to vision and hearing began to be identified, both macro and microscopically, from the second day of incubation. The vesicles from the primitive central nervous system-forebrain, midbrain, and hindbrain-were identified on the third day of incubation. On the sixth day of incubation, there was a clear vascularization of the skin. The optic vesicle was first observed fourth day of development and on the fifth day there was the beginning of the lens formation. Although embryonic development is influenced by animal line as well as external factors such as incubation temperature, this paper provides a chronological description for chicken (Gallus gallus domesticus) during its embryonic development. Copyright © 2013 Wiley Periodicals, Inc.

  9. Analysis of Drosophila melanogaster proteome dynamics during embryonic development by a combination of label-free proteomics approaches.

    Science.gov (United States)

    Fabre, Bertrand; Korona, Dagmara; Groen, Arnoud; Vowinckel, Jakob; Gatto, Laurent; Deery, Michael J; Ralser, Markus; Russell, Steven; Lilley, Kathryn S

    2016-08-01

    During embryogenesis, organisms undergo considerable cellular remodelling requiring the combined action of thousands of proteins. In case of the well-studied model Drosophila melanogaster, transcriptomic studies, most notably from the modENCODE project, have described in detail changes in gene expression at the mRNA level across development. Although such data are clearly very useful to understand how the genome is regulated during embryogenesis, it is important to understand how changes in gene expression are reflected at the level of the proteome. In this study, we describe a combination of two quantitative label-free approaches, SWATH and data-dependent acquisition, to monitor changes in protein expression across a timecourse of D. melanogaster embryonic development. We demonstrate that both approaches provide robust and reproducible methods for the analysis of proteome changes. In a preliminary analysis of Drosophila embryogenesis, we identified several pathways, including the heat-shock response, nuclear protein import and energy production that are regulated during embryo development. In some cases changes in protein expression mirrored transcript levels across development, whereas other proteins showed signatures of post-transcriptional regulation. Taken together, our pilot study provides a solid platform for a more detailed exploration of the embryonic proteome. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Fecundity, embryonic and ovarian development of blue swimming crab, Portunus pelagicus (Linnaeus, 1758) in coastal water of Johor, Malaysia.

    Science.gov (United States)

    Ikhwanuddin, M; Azra, M N; Siti-Aimuni, H; Abol-Munafi, A B

    2012-08-01

    Blue swimming crab, Portunus pelagicus is widely study and research throughout the Indo-West Pacific, but little is known of its reproductive biology in Malaysia. The present study describes the fecundity, embryonic development and ovarian development stages of the P. pelagicus from Johor coastal water, Malaysia. Carapace width range of berried crabs sampled was from 9.64 to 13.32 cm, while the body weight range was from 75 to 235 g. The mean number of egg produced by females in different sizes ranged from 105443.333 +/- 35448.075 per eggs batch. Mean egg size during embryonic development at stage 1 was 0.307 +/- 0.037, while 0.386 +/- 0.039 and 0.396 +/- 0.033 for stage 2 and stage 3, respectively. Study showed that there was significant (p < 0.05) relationship between the number of eggs and carapace width/body weight. Mean diameter oocyte during ovarian development at stage 1 was 97.732 +/- 12.391 while for stage 2 was 149.516 +/- 23.287. Stage 3 showed increasingly of size with mean diameter was 158.506 +/- 27.616 and 181.013 +/- 24.339 for stage 4.

  11. Development of nylon-based artificial muscles for the usage in robotic prosthetic limb

    Science.gov (United States)

    Atikah, Nurul Anis; Weng, Leong Yeng; Anuar, Adzly; Fat, Chau Chien; Abidin, Izham Zainal; Sahari, Khairul Salleh Mohamed

    2017-09-01

    This paper describes the development of nylon-based artificial muscles that is intended to be used in prosthetic limb for young amputees. Prosthetic limbs are very expensive and this situation is further compounded for young amputees who are very quickly out-grow their prosthesis. The proposed artificial muscles are made of nylon fishing strings from various size such as 0.45mm, 0.55mm, 0.65mm and 1.00mm. These fishing strings were twisted into coils to create Super Coiled Polymers (SCP) and tested using hot air blower. These artificial muscles react counterintuitively, where when it is exposed to heat, contracts, and when cooled, expands. Peltier devices, when switched-on acts as heat pump, where one side is hot and the other is cold. This phenomenon, when affixed in between 2 SCP's, creates tandem motion similar to triceps and biceps. As initial study, the hot side of the Peltier module was tested using these artificial muscles. The string was measured for both its force production, length contraction, the initial results were promising.

  12. Hormone-mediated maternal stress affects embryonic development during incubation without adverse effect on chick weight and body composition.

    Science.gov (United States)

    Babacanoğlu, E; Yalçin, S

    2014-01-01

    1. The objective of this study was to evaluate the effect of maternal stress (MS) induced by supplementing the hen's diet with 2 mg/hen/d dietary corticosterone (CORT) on embryonic development, biochemical blood parameters and hatching performance of broiler chicks. 2. A total of 200 Ross broiler breeder hens at 42 weeks of age were randomly divided into two groups: MS or control. Hens in the MS were fed 2 mg/hen/d CORT for 14 d. Eggs (648 and 635 eggs for MS and control, respectively) were collected from d 3 to 14 of dietary CORT supplementation and incubated. Weights of embryo, chicks and organs and body composition were determined during incubation and at hatch. Biochemical blood parameters were measured at internal pipping stage and day of hatch. Hatching performance and embryonic mortalities were recorded. 3. Hens fed a diet supplemented with CORT had lighter body weight and produced less eggs at the end of the 14-d treatment period. Although MS embryos were heavier than control from 12 to 18 d of incubation, chick weight was similar at the day of hatch. Lower relative weights for yolk sac and bursa were observed at 12 d of incubation for MS chicks compared to control. Chicks from both groups had similar body content in spite of higher fat content of MS embryos on d 18 of incubation. 4. MS had no effect on the duration of incubation or hatching performance but increased mortality at the pipping stage. 5. The results suggest that hormone-mediated MS might affect embryonic development during incubation without adverse effect on chick weight and body composition.

  13. Embryonic and larval development of Eugerres mexicanus (Perciformes: Gerreidae in Tenosique: Tabasco, Mexico

    Directory of Open Access Journals (Sweden)

    Raúl E Hernández

    2012-03-01

    Full Text Available Most studies on Eugerres mexicanus mainly consider biogeographic and systematic aspects and rarely address reproductive characteristics, which are useful for fishery population management plans. This study aimed at evaluating the ontogeny of E. mexicanus, based on 30 embryos and 30 larvae sampled by induced spawning of breeders, taken in February 2009 from the Usumacinta River in Tenosique, Tabasco, Mexico. All descriptions of the embryonic development were based on morphometric and meristic data and followed standard methods. Eggs, recovered at the gastrula stage, had an average diameter of 1.17mm (SD=0.08. The bud stage appeared during the first three hours of development, in which the posterior side was adhered to the vitellus; Kupffer´s vesicle was visible. Yolk-sac larvae hatched 18 hours after fertilization, exhibiting a light brown color and an average total length of 2.94mm (SD=0.70; the preflexion stage was reached eight days after hatching, with a total average length of 4.67mm (SD=0.50 and a total notochord length of 4.45mm (SD=0.50. The flexion stage was reached on the 16th day, with an average total length of 6.66mm (SD=1.53, while postflexion was reached on the 24th day, with 10.33mm (SD=1.45. The pre-juvenile stage was reached on the 33rd day, with a total length of 14.30mm (SD=0.93, showing IX spines and 10 rays and III spines and eight rays in the dorsal and anal fins, respectively. The juvenile stage was reached by the 45th day, with an average length of 28.16mm (SD=1.93 and average weight of 4.75g (SD=1.49. Prejuveniles showed an initial pigmentation with dark colored dots in the superior and inferior jaw and dispersed on the head, while juveniles presented the same pigmentation pattern, decreasing towards the margin of the caudal peduncle. In conclusion, the embryonic developmental stages of E. mexicanus were typical for the Gerreidae group. However, their morphometric characters were slightly different since the diameter

  14. Development of Quasi-3DOF upper limb rehabilitation system using ER brake: PLEMO-P1

    Science.gov (United States)

    Kikuchi, T.; Fukushima, K.; Furusho, J.; Ozawa, T.

    2009-02-01

    In recent years, many researchers have studied the potential of using robotics technology to assist and quantify the motor functions for neuron-rehabilitation. Some kinds of haptic devices have been developed and evaluated its efficiency with clinical tests, for example, upper limb training for patients with spasticity after stroke. However, almost all the devices are active-type (motor-driven) haptic devices and they basically require high-cost safety system compared to passive-type (brake-based) devices. In this study, we developed a new practical haptic device 'PLEMO-P1'; this system adopted ER brakes as its force generators. In this paper, the mechanism of PLEMO-P1 and its software for a reaching rehabilitation are described.

  15. Development of Quasi-3DOF upper limb rehabilitation system using ER brake: PLEMO-P1

    International Nuclear Information System (INIS)

    Kikuchi, T; Fukushima, K; Furusho, J; Ozawa, T

    2009-01-01

    In recent years, many researchers have studied the potential of using robotics technology to assist and quantify the motor functions for neuron-rehabilitation. Some kinds of haptic devices have been developed and evaluated its efficiency with clinical tests, for example, upper limb training for patients with spasticity after stroke. However, almost all the devices are active-type (motor-driven) haptic devices and they basically require high-cost safety system compared to passive-type (brake-based) devices. In this study, we developed a new practical haptic device 'PLEMO-P1'; this system adopted ER brakes as its force generators. In this paper, the mechanism of PLEMO-P1 and its software for a reaching rehabilitation are described.

  16. Development of Quasi-3DOF upper limb rehabilitation system using ER brake: PLEMO-P1

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, T; Fukushima, K; Furusho, J; Ozawa, T [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)], E-mail: kikuchi@mech.eng.osaka-u.ac.jp

    2009-02-01

    In recent years, many researchers have studied the potential of using robotics technology to assist and quantify the motor functions for neuron-rehabilitation. Some kinds of haptic devices have been developed and evaluated its efficiency with clinical tests, for example, upper limb training for patients with spasticity after stroke. However, almost all the devices are active-type (motor-driven) haptic devices and they basically require high-cost safety system compared to passive-type (brake-based) devices. In this study, we developed a new practical haptic device 'PLEMO-P1'; this system adopted ER brakes as its force generators. In this paper, the mechanism of PLEMO-P1 and its software for a reaching rehabilitation are described.

  17. FGF/EGF signaling regulates the renewal of early nephron progenitors during embryonic development.

    Science.gov (United States)

    Brown, Aaron C; Adams, Derek; de Caestecker, Mark; Yang, Xuehui; Friesel, Robert; Oxburgh, Leif

    2011-12-01

    Recent studies indicate that nephron progenitor cells of the embryonic kidney are arranged in a series of compartments of an increasing state of differentiation. The earliest progenitor compartment, distinguished by expression of CITED1, possesses greater capacity for renewal and differentiation than later compartments. Signaling events governing progression of nephron progenitor cells through stages of increasing differentiation are poorly understood, and their elucidation will provide key insights into normal and dysregulated nephrogenesis, as well as into regenerative processes that follow kidney injury. In this study, we found that the mouse CITED1(+) progenitor compartment is maintained in response to receptor tyrosine kinase (RTK) ligands that activate both FGF and EGF receptors. This RTK signaling function is dependent on RAS and PI3K signaling but not ERK. In vivo, RAS inactivation by expression of sprouty 1 (Spry1) in CITED1(+) nephron progenitors results in loss of characteristic molecular marker expression and in increased death of progenitor cells. Lineage tracing shows that surviving Spry1-expressing progenitor cells are impaired in their subsequent epithelial differentiation, infrequently contributing to epithelial structures. These findings demonstrate that the survival and developmental potential of cells in the earliest embryonic nephron progenitor cell compartment are dependent on FGF/EGF signaling through RAS.

  18. Promotion of hair follicle development and trichogenesis by Wnt-10b in cultured embryonic skin and in reconstituted skin

    International Nuclear Information System (INIS)

    Ouji, Yukiteru; Yoshikawa, Masahide; Shiroi, Akira; Ishizaka, Shigeaki

    2006-01-01

    We previously showed that Wnt-10b promoted the differentiation of primary skin epithelial cells (MPSEC) toward hair shaft and inner root sheath of the hair follicle (IRS) cells in vitro. In the present study, we found that Wnt-10b promotes the development of hair follicles using a culture of mouse embryonic skin tissue and trichogenesis using a reconstitution experiment with nude mice. Hair follicle development was observed in skin taken from mouse embryos on embryonic day 10.5 following a 2-day culture with recombinant Wnt-10b (rWnt-10b), however, not without rWnt-10b. Brown hair growth was observed at the site of reconstituted skin in Balb/c nude mice where dermal fibroblasts and keratinocytes, derived from C3H/HeN new born mice, were transplanted with Wnt-10b-producing COS cells (Wnt-COS). Without the co-transplantation of Wnt-COS, no hair growth was observed. Our results suggest an important role of Wnt-10b in the initiation of hair follicle development and following trichogenesis

  19. The zebrafish digital embryo: in toto reconstruction of zebrafish early embryonic development with digital scanned laser light sheet fluorescence microscopy

    Science.gov (United States)

    Keller, Philipp J.; Schmidt, Annette D.; Wittbrodt, Joachim; Stelzer, Ernst H. K.

    2009-07-01

    The analysis of all cell movements and all cell interactions in a vertebrate during the entire period of embryonic development is a fundamental goal in biology. Using DSLM, we recorded the development of entire zebrafish embryos in vivo and with sub-cellular resolution. By imaging at a speed of 1.5 billion volume elements per minute, image data in the order of several terabytes were acquired for each embryo over the time course of an entire day, i.e. up to a stage, in which the embryo comprises 20,000 cells and major organs are in a functional state. By using automated image processing algorithms the image data of each embryo were converted into a digital representation of the embryo (the "digital embryo"), i.e. a database with comprehensive information about migratory tracks and divisions of the embryo's cells. The digital embryos permit to follow single cells as a function of time such that the "fate" as well as the origin of the cells can be reconstructed. By means of these analyses, developmental blueprints of tissues and organs can be determined in a whole-embryo context. Defects in embryonic development or disease models can now be analyzed and understood on a quantitative level.

  20. NSrp70 is significant for embryonic growth and development, being a crucial factor for gastrulation and mesoderm induction.

    Science.gov (United States)

    Lee, Soo-Ho; Kim, Chowon; Lee, Hyun-Kyung; Kim, Yoo-Kyung; Ismail, Tayaba; Jeong, Youngeun; Park, Kyungyeon; Park, Mae-Ja; Park, Do-Sim; Lee, Hyun-Shik

    2016-10-14

    NSrp70 (nuclear speckle-related protein 70), a recently discovered protein and it belongs to the serine/arginine (SR) rich related protein family. NSrp70 is recognized as an important splicing factor comprising RNA recognition motif (RRM) and arginine/serine (RS)-like regions at the N- and C-terminus respectively, along with two coiled coil domains at each terminus. However, other functions of NSrp70 remain unelucidated. In this study, we investigated the role of NSrp70 in Xenopus embryogenesis and found that its maternal expression plays a critical role in embryonic development. Knockdown of NSrp70 resulted in dramatic reduction in the length of developing tadpoles and mild to severe malformation in Xenopus embryos. In addition, knockdown of NSrp70 resulted in an extremely short axis by blocking gastrulation and convergent extension. Further, animal cap assays along with activin A treatment revealed that NSrp70 is an essential factor for dorsal mesoderm induction as knockdown of NSrp70 caused a dramatic down-regulation of dorsal mesoderm specific genes and its loss significantly shortened the elongation region of animal caps. In conclusion, NSrp70 is crucial for early embryonic development, influencing gastrulation and mesoderm induction. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. The effects of neonicotinoid exposure on embryonic development and organ mass in northern bobwhite quail (Colinus virginianus).

    Science.gov (United States)

    Gobeli, Amanda; Crossley, Dane; Johnson, Jeff; Reyna, Kelly

    2017-05-01

    Since their emergence in the early 1990s, neonicotinoid use has increased exponentially to make them the world's most prevalent insecticides. Although there has been considerable research concerning the lethality of neonicotinoids, their sub-lethal and developmental effects are still being explored, especially with regard to non-mammalian species. The goal of this research was to investigate the effects of the neonicotinoid imidacloprid on the morphological and physiological development of northern bobwhite quail (Colinus virginianus). Bobwhite eggs (n=390) were injected with imidacloprid concentrations of 0 (sham), 10, 50, 100, and 150mg/kg of egg mass, which was administered at day 0 (pre-incubation), 3, 6, 9, or 12 of growth. Embryos were dissected, weighed, staged, and examined for any overt structural deformities after 19days of incubation. The mass of the embryonic heart, liver, lungs and kidneys was also recorded. The majority of treatments produced no discernible differences in embryo morphology; however, in some instances, embryos were subject to increased frequency of anatomical deformity and altered organ masses. Some impacts were more pronounced in specific dosing periods, implying that there may be critical windows of development when embryos are more susceptible to neonicotinoid exposure. This investigation suggests that imidacloprid has the potential to impact bobwhite quail embryonic development and chick survival. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Persistent expression of BMP-4 in embryonic chick adrenal cortical cells and its role in chromaffin cell development

    Directory of Open Access Journals (Sweden)

    Halbach Oliver

    2008-10-01

    Full Text Available Abstract Background Adrenal chromaffin cells and sympathetic neurons both originate from the neural crest, yet signals that trigger chromaffin development remain elusive. Bone morphogenetic proteins (BMPs emanating from the dorsal aorta are important signals for the induction of a sympathoadrenal catecholaminergic cell fate. Results We report here that BMP-4 is also expressed by adrenal cortical cells throughout chick embryonic development, suggesting a putative role in chromaffin cell development. Moreover, bone morphogenetic protein receptor IA is expressed by both cortical and chromaffin cells. Inhibiting BMP-4 with noggin prevents the increase in the number of tyrosine hydroxylase positive cells in adrenal explants without affecting cell proliferation. Hence, adrenal BMP-4 is likely to induce tyrosine hydroxylase in sympathoadrenal progenitors. To investigate whether persistent BMP-4 exposure is able to induce chromaffin traits in sympathetic ganglia, we locally grafted BMP-4 overexpressing cells next to sympathetic ganglia. Embryonic day 8 chick sympathetic ganglia, in addition to principal neurons, contain about 25% chromaffin-like cells. Ectopic BMP-4 did not increase this proportion, yet numbers and sizes of 'chromaffin' granules were significantly increased. Conclusion BMP-4 may serve to promote specific chromaffin traits, but is not sufficient to convert sympathetic neurons into a chromaffin phenotype.

  3. A macroscopic classification of the embryonic development of the one-sided livebearer Jenynsia multidentata (Teleostei: Anablepidae

    Directory of Open Access Journals (Sweden)

    Nathalia C. López-Rodríguez

    2017-12-01

    Full Text Available ABSTRACT This study proposes eight stages according to the main discernible changes recorded throughout the embryonic development of Jenynsia multidentata. The development of morphological embryo structures, pigmentation, and changes in tissues connecting mother and embryo were included in the stage characterization. From the fertilized egg (Stage 1, an embryo reaches the intermediary stages when presenting yolk syncytial layer (Stage 2, initial pigmentation of the outer layers of the retina and dorsal region of the head (Stage 3, and the sprouting of the caudal (Stage 4, dorsal and anal fins (Stage 5. During the later stages, the ovarian folds enter the gills, and the body pigmentation becomes more intense (Stage 6, the body becomes elongated (Stage 7, and there is a greater intensity in body pigmentation and increased muscle mass (Stage 8. The dry weight of the batches varied between 0.6 ± 0.3 mg (Stage 3 to 54.6 ± 19.7 mg (Stage 8, but the dry weight of the maternal-embryonic connecting tissues remained almost constant. After controlling the effect of those reproductive tissues, the gain in dry weight of the batches throughout development increased exponentially from Stage 6, reflecting the increase in size and weight of the embryos due to matrotrophy.

  4. EMBRYONIC AND LARVAL DEVELOPMENT OF A RED STRAIN OF THE EGYPTIAN AFRICAN CATFISH (Clarias gariepinus Burchell, 1822

    Directory of Open Access Journals (Sweden)

    Bambang Iswanto

    2015-06-01

    Full Text Available Egyptian African catfish is one of several African catfish (Clarias gariepinus strains introduced to Indonesia. Several breeding activities using that strain in Sukamandi resulted in some individuals with redish-yellow body colour (a red strain. Biological informations related to aquacultural aspects of that red strain were still scarce. The present study aimed to elucidate the embryonic and larval developments of the red strain compared to those of the black (normal coloured one, using the progenies obtained from artificial spawning of each red and black coloured brooders. Results of the present study revealed that embryonic developments of the red and black strains were similar. Their larval development were also quite similar, however, both larvae could be distinguished based on the pigmentation. The red strain larvae were golden-red-yellowish in colour, while the black strain larvae were greyish covered with dense melanophores. Total length of the red strain larvae tended to be lower than those of the black strain.

  5. Micro-computed tomography-based phenotypic approaches in embryology: procedural artifacts on assessments of embryonic craniofacial growth and development

    Directory of Open Access Journals (Sweden)

    Logan C Cairine

    2010-02-01

    Full Text Available Abstract Background Growing demand for three dimensional (3D digital images of embryos for purposes of phenotypic assessment drives implementation of new histological and imaging techniques. Among these micro-computed tomography (μCT has recently been utilized as an effective and practical method for generating images at resolutions permitting 3D quantitative analysis of gross morphological attributes of developing tissues and organs in embryonic mice. However, histological processing in preparation for μCT scanning induces changes in organ size and shape. Establishing normative expectations for experimentally induced changes in size and shape will be an important feature of 3D μCT-based phenotypic assessments, especially if quantifying differences in the values of those parameters between comparison sets of developing embryos is a primary aim. Toward that end, we assessed the nature and degree of morphological artifacts attending μCT scanning following use of common fixatives, using a two dimensional (2D landmark geometric morphometric approach to track the accumulation of distortions affecting the embryonic head from the native, uterine state through to fixation and subsequent scanning. Results Bouin's fixation reduced average centroid sizes of embryonic mouse crania by approximately 30% and substantially altered the morphometric shape, as measured by the shift in Procrustes distance, from the unfixed state, after the data were normalized for naturally occurring shape variation. Subsequent μCT scanning produced negligible changes in size but did appear to reduce or even reverse fixation-induced random shape changes. Mixtures of paraformaldehyde + glutaraldehyde reduced average centroid sizes by 2-3%. Changes in craniofacial shape progressively increased post-fixation. Conclusions The degree to which artifacts are introduced in the generation of random craniofacial shape variation relates to the degree of specimen dehydration during the

  6. Micro-computed tomography-based phenotypic approaches in embryology: procedural artifacts on assessments of embryonic craniofacial growth and development.

    Science.gov (United States)

    Schmidt, Eric J; Parsons, Trish E; Jamniczky, Heather A; Gitelman, Julian; Trpkov, Cvett; Boughner, Julia C; Logan, C Cairine; Sensen, Christoph W; Hallgrímsson, Benedikt

    2010-02-17

    Growing demand for three dimensional (3D) digital images of embryos for purposes of phenotypic assessment drives implementation of new histological and imaging techniques. Among these micro-computed tomography (microCT) has recently been utilized as an effective and practical method for generating images at resolutions permitting 3D quantitative analysis of gross morphological attributes of developing tissues and organs in embryonic mice. However, histological processing in preparation for microCT scanning induces changes in organ size and shape. Establishing normative expectations for experimentally induced changes in size and shape will be an important feature of 3D microCT-based phenotypic assessments, especially if quantifying differences in the values of those parameters between comparison sets of developing embryos is a primary aim. Toward that end, we assessed the nature and degree of morphological artifacts attending microCT scanning following use of common fixatives, using a two dimensional (2D) landmark geometric morphometric approach to track the accumulation of distortions affecting the embryonic head from the native, uterine state through to fixation and subsequent scanning. Bouin's fixation reduced average centroid sizes of embryonic mouse crania by approximately 30% and substantially altered the morphometric shape, as measured by the shift in Procrustes distance, from the unfixed state, after the data were normalized for naturally occurring shape variation. Subsequent microCT scanning produced negligible changes in size but did appear to reduce or even reverse fixation-induced random shape changes. Mixtures of paraformaldehyde + glutaraldehyde reduced average centroid sizes by 2-3%. Changes in craniofacial shape progressively increased post-fixation. The degree to which artifacts are introduced in the generation of random craniofacial shape variation relates to the degree of specimen dehydration during the initial fixation. Fixation methods that

  7. Development of a Novel Tissue Engineering Strategy Towards Whole Limb Regeneration

    National Research Council Canada - National Science Library

    Laurencin, Cato T

    2008-01-01

    .... In contrast to the bottom up approach of limb regeneration that relies on blastema formation outgrowth and cell dedifferentiation as seen in amphibians and lower vertebrates tissue engineering...

  8. Synergistic Function of E2F7 and E2F8 is Essential for Cell Survival and Embryonic Development

    Science.gov (United States)

    Li, Jing; Ran, Cong; Li, Edward; Gordon, Faye; Comstock, Grant; Siddiqui, Hasan; Cleghorn, Whitney; Chen, Hui-zi; Kornacker, Karl; Pandit, Shusil K.; Khanizadeh, Mehrbod; Weinstein, Michael; Leone, Gustavo; de Bruin, Alain

    2008-01-01

    Summary The novel E2f7 and E2f8 family members are thought to function as transcriptional repressors important for the control of cell proliferation. Here we have analyzed the consequences of inactivating E2f7 and E2f8 in mice and show that their individual loss had no significant effect on development. Their combined ablation, however, resulted in massive apoptosis and dilation of blood vessels, culminating in lethality by embryonic day E11.5. A deficiency in E2f7 and E2f8 led to an increase in E2f1 and p53, as well as in many stress-related genes. Homo- and hetero-dimers of E2F7 and E2F8 were found on target promoters, including E2f1. Importantly, loss of either E2f1 or p53 suppressed the massive apoptosis in double mutant embryos. These results identify E2F7 and E2F8 as a unique repressive arm of the E2F transcriptional network that is critical for embryonic development and control of the E2F1-p53 apoptotic axis. PMID:18194653

  9. Identification and characterization of L1-specific endo-siRNAs essential for early embryonic development in pig.

    Science.gov (United States)

    Zhang, Heng; Liu, Jilong; Tai, Yurong; Zhang, Xiaolei; Zhang, Jiaming; Liu, Shichao; Lv, Jiawei; Liu, Zhonghua; Kong, Qingran

    2017-04-04

    Small noncoding RNAs (sncRNAs) play important roles in RNA interference (RNAi). In addition to microRNA (miRNA) and Piwi-interacting RNA (piRNA), one key member of sncRNAs group is endogenous small interfering RNA (endo-siRNA). Some studies do show the role of endo-siRNAs in Dicer and/or Ago mutants, however, the biological functions of specific endo-siRNAs remains mostly unanswered. In the study, we have performed a comparative analysis of endo-siRNAs present in porcine sperms, oocytes and zygotes, identified by deep sequencing and bioinformatics analysis. Further, we observe a large amount of endo-siRNAs specific binding on ORF2 and 3' UTR of porcine L1 (L1-siRNAs). And, 9 L1-siRNAs generated from a dsRNA formed between L1 transcript and a newly identified an antisense noncoding RNA was characterized. We show the L1-siRNAs regulate early embryonic development by inhibiting the activity of L1 retrotransposition. This work can contribute to understanding the functional role of abundant endo-siRNAs in embryonic development.

  10. Development of chain limbing and small-drum barking equipment; Ketjukarsinta- ja pienrumpukuorintaan perustuvan laitteiston kehittaeminen tuotantovalmiiksi

    Energy Technology Data Exchange (ETDEWEB)

    Rieppo, K. [Metsaeteho Oy, Helsinki (Finland); Hakkila, P.; Kalaja, H. [Finnish Forest Research Inst., Vantaa (Finland)

    1997-12-01

    Three test series were carried out in 1996 at the chain limbing- drum barking station developed by Pertti Szepaniak Oy. The test equipment was developed during the test series. During the first experiment in February the wood used was frozen. In this test series the whipping efficiency was insignificant and consequently, the bark contents remained too large. In the second test in September the whipping efficiency was too high and was not easy to adjust, and as a consequence the wood loss was unreasonable. In the third test in November, when the wood was not yet frozen, the whipping efficiency was correct and promising results were obtained both with regard to the bark content and wood loss. Limbed pine pulpwood was used as raw material. The bark contents of the chips ranged from 0.2 to 0.4 % and the wood loss in barking from 2.8 to 3.6 %. The productivity also improved clearly during the tests. The experiments indicated that a separate station based on a combination of chain limbing- barking and drum-barking is able to produce high-grade pulp chips both from limbed and non-limbed first-thinning pine wood. (orig.)

  11. The effect of dietary protein on reproduction in the mare. VII. Embryonic development, early embryonic death, foetal losses and their relationship with serum progestagen

    Directory of Open Access Journals (Sweden)

    F.E. Van Niekerk

    1998-07-01

    Full Text Available Sixty-four Thoroughbred and Anglo-Arab mares aged 6-12 years were randomly allocated to 4 dietary groups and fed diets that differed in the total protein content and quality (essential amino-acids. Forty mares were non-lactating and 24 lactating. Eight mares were withdrawn from the investigation owing to injuries or gynaecological pathology. An overall conception rate of 94.6%and a foaling rate of 80%was achieved. Five of 14 (35.7 % mares (Group 1 fed a low-quality protein diet suffered from early embryonic loss before 90 days of pregnancy compared to 3 of 41 (7.3 % mares in the remaining groups that received the higher-quality protein in their diets. Serum progestagen concentrations of mares in Group 1 that suffered foetal loss were indicative of luteal function insufficiency during the 1st 40 days post-ovulation. Non-lactating mares in all 4 groups gained on average approximately 30 kg in mass during the 90 days before the breeding period. Lactating mares in Group 1 (low-quality protein lost on average 25 kg in mass during lactation, with no weight loss observed among the lactating mares in the other 3 groups. No difference in the diameter of the embryonic vesicle was found between dietary groups until Day 35 of pregnancy.

  12. Ground reaction forces and lower-limb joint kinetics of turning gait in typically developing children.

    Science.gov (United States)

    Dixon, Philippe C; Stebbins, Julie; Theologis, Tim; Zavatsky, Amy B

    2014-11-28

    Turning is a common locomotor task essential to daily activity; however, very little is known about the forces and moments responsible for the kinematic adaptations occurring relative to straight-line gait in typically developing children. Thus, the aims of this study were to analyse ground reaction forces (GRFs), ground reaction free vertical torque (TZ), and the lower-limb joint kinetics of 90° outside (step) and inside (spin) limb turns. Step, spin, and straight walking trials from fifty-four typically developing children were analysed. All children were fit with the Plug-in Gait and Oxford Foot Model marker sets while walking over force plates embedded in the walkway. Net internal joint moments and power were computed via a standard inverse dynamics approach. All dependent variables were statistically analysed over the entire curves using the mean difference 95% bootstrap confidence band approach. GRFs were directed medially for step turns and laterally for spin turns during the turning phase. Directions were reversed and magnitudes decreased during the approach phase. Step turns showed reduced ankle power generation, while spin turns showed large TZ. Both strategies required large knee and hip coronal and transverse plane moments during swing. These kinetic differences highlight adaptations required to maintain stability and reorient the body towards the new walking direction during turning. From a clinical perspective, turning gait may better reveal weaknesses and motor control deficits than straight walking in pathological populations, such as children with cerebral palsy, and could potentially be implemented in standard gait analysis sessions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. cables1 Is Required for Embryonic Neural Development: Molecular, Cellular, and Behavioral Evidence From the Zebrafish

    Science.gov (United States)

    GROENEWEG, JOLIJN W.; WHITE, YVONNE A.R.; KOKEL, DAVID; PETERSON, RANDALL T.; ZUKERBERG, LAWRENCE R.; BERIN, INNA; RUEDA, BO R.; WOOD, ANTONY W.

    2014-01-01

    SUMMARY In vitro studies have suggested that the Cables1 gene regulates epithelial cell proliferation, whereas other studies suggest a role in promoting neural differentiation. In efforts to clarify the functions of Cables1 in vivo, we conducted gain- and loss-of-function studies targeting its ortholog (cables1) in the zebrafish embryo. Similar to rodents, zebrafish cables1 mRNA expression is detected most robustly in embryonic neural tissues. Antisense knockdown of cables1 leads to increased numbers of apoptotic cells, particularly in brain tissue, in addition to a distinct behavioral phenotype, characterized by hyperactivity in response to stimulation. Apoptosis and the behavioral abnormality could be rescued by co-expression of a morpholino-resistant cables1 construct. Suppression of p53 expression in cables1 morphants partially rescued both apoptosis and the behavioral phenotype, suggesting that the phenotype of cables1 morphants is due in part to p53-dependent apoptosis. Alterations in the expression patterns of several neural transcription factors were observed in cables1 morphants during early neurulation, suggesting that cables1 is required for early neural differentiation. Ectopic overexpression of cables1 strongly disrupted embryonic morphogenesis, while overexpression of a cables1 mutant lacking the C-terminal cyclin box had little effect, suggesting functional importance of the cyclin box. Lastly, marked reductions in p35, but not Cdk5, were observed in cables1 morphants. Collectively, these data suggest that cables1 is important for neural differentiation during embryogenesis, in a mechanism that likely involves interactions with the Cdk5/p35 kinase pathway. PMID:21268180

  14. Changes in the levels, expression, and possible roles of serotonin and dopamine during embryonic development in the giant freshwater prawn, Macrobrachium rosenbergii.

    Science.gov (United States)

    Tinikul, Yotsawan; Poljaroen, Jaruwan; Tinikul, Ruchanok; Sobhon, Prasert

    2016-01-01

    We investigated the changes in the levels of serotonin (5-HT) and dopamine (DA), and their possible roles during embryonic development of the freshwater prawn, Macrobrachium rosenbergii. The 5-HT and DA concentrations were quantified using high performance liquid chromatography with electrochemical detection (HPLC-ECD). The levels of 5-HT and DA gradually increased from early developing embryos to late developing embryos. The 5-HT concentrations gradually increased from the pale yellow egg to orange egg stages, and reaching a maximum at the black egg stage. DA concentrations were much lower in the early embryos than those of 5-HT (P<0.05), and gradually increased to reach the highest level at the black egg stage. Immunohistochemically, 5-HT was firstly detected in the early embryonic stages, whereas DA developed later than 5-HT. Functionally, 5-HT-treated female prawns at doses of 2.5×10(-5), 2.5×10(-6) and 2.5×10(-7)mol/prawn, produced embryos with significantly shortened lengths of early embryonic stages, whereas DA-treated prawns at all three doses, exerted its effects by significantly lengthening the period of mid-embryonic stage onwards. These results suggest significant involvement of 5-HT and DA in embryonic developmental processes of this species. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Early intrauterine embryonic development in Khawia sinensis Hsü, 1935 (Cestoda, Caryophyllidea, Lytocestidae), an invasive tapeworm of carp (Cyprinus carpio): an ultrastructural study.

    Science.gov (United States)

    Bruňanská, Magdaléna; Mackiewicz, John S; Młocicki, Daniel; Swiderski, Zdzisław; Nebesářová, Jana

    2012-02-01

    Intrauterine embryonic development in the caryophyllidean tapeworm Khawia sinensis has been investigated using transmission electron microscopy and cytochemical staining with periodic acid-thiosemicarbazide-silver proteinate for glycogen. Contrary to previous light microscopy findings that reported the release of non-embryonated eggs of K. sinenesis to the external environment, the present study documents various stages of embryonation (ovoviviparity) within the intrauterine eggs of this cestode. At the initial stage of embryonic development, each fertilised oocyte is accompanied by several vitellocytes that become enclosed within the operculate, electrondense shell. Cleavage divisions result in formation of blastomeres (up to about 24 cells) of various sizes. Mitotic divisions and apparent rosette arrangment of the blastomeres, the latter atypical within the Eucestoda, are observed for the first time in the intrauterine eggs of K. sinenesis. The early embryo enclosed within the electrondense shell is surrounded by a thin membraneous layer which in some enlarged regions shows presence of nuclei. Simultaneously to multiplication and differentiation, some of the blastomeres undergo deterioration. A progressive degeneration of the vitellocytes within eggs provides nutritive reserves, including lipids, for the developing embryo. The possible significance of this atypical timing of the intrauterine embryonic development to (1) the ecology of K. sinensis and that of a recent introduction of another invasive tapeworm, the caryophyllidean Atractolytocestus huronensis Anthony, 1958 to Europe; and (2) the affiliation of caryophyllideans with other lower cestodes, are discussed.

  16. Conserved versus derived patterns of controlled cell death during the embryonic development of two species of Onychophora (velvet worms).

    Science.gov (United States)

    Treffkorn, Sandra; Mayer, Georg

    2017-05-01

    Apoptosis is involved in various developmental processes, including cell migration and tissue and organ formation. Some of these processes are conserved across metazoans, while others are specific to particular taxa. Although the patterns of apoptosis have been investigated in arthropods, no corresponding data are available from one of their closest relatives, the Onychophora (velvet worms). We analyzed the patterns of apoptosis in embryos of two onychophoran species: the lecithotrophic/matrotrophic viviparous peripatopsid Euperipatoides rowelli, and the placentotrophic viviparous peripatid Principapillatus hitoyensis. Our data show that apoptosis occurs early in development and might be responsible for the degeneration of extra-embryonic tissues. Moreover, apoptosis might be involved in the morphogenesis of the ventral and preventral organs in both species and occurs additionally in the placental stalk of P. hitoyensis. Despite the different developmental modes in these onychophoran species, our data suggest that patterns of apoptosis are conserved among onychophorans. While apoptosis in the dorsal extra-embryonic tissue might contribute to dorsal closure-a process also known from arthropods-the involvement of apoptosis in ventral closure might be unique to onychophorans. Apoptosis in the placental stalk of P. hitoyensis is most likely a derived feature of the placentotrophic onychophorans. Developmental Dynamics 246:403-416, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  17. Genomic and Functional Analysis of the Toxic Effect of Tachyplesin I on the Embryonic Development of Zebrafish

    Directory of Open Access Journals (Sweden)

    Hongya Zhao

    2014-01-01

    Full Text Available Tachyplesin I (TP I is an antimicrobial peptide isolated from the hemocytes of the horseshoe crab. With the developments of DNA microarray technology, the genetic analysis of the toxic effect of TP I on embryo was originally considered in our recent study. Based on our microarray data of the embryonic samples of zebrafish treated with the different doses of TP I, we performed a series of statistical data analyses to explore the toxic effect of TP I at the genomic level. In this paper, we first employed the hexaMplot to illustrate the continuous variation of the gene expressions of the embryonic cells treated with the different doses of TP I. The probabilistic model-based Hough transform was used to classify these differentially coexpressed genes of TP I on the zebrafish embryos. As a result, three line rays supported with the corresponding 174 genes were detected in our analysis. Some biological processes of the featured genes, such as antigen processing, nuclear chromatin, and structural constituent of eye lens, were significantly filtered with the smaller P values.

  18. Permanent brachial plexus birth palsy does not impair the development and function of the spine and lower limbs.

    Science.gov (United States)

    Kirjavainen, Mikko O; Remes, Ville M; Peltonen, Jari; Helenius, Ilkka J; Rautakorpi, Sanna M; Vähäsarja, Vesa J; Pöyhiä, Tiina H; Nietosvaara, Yrjänä

    2009-11-01

    Permanent brachial plexus birth palsy (BPBP) impairs the function of the affected upper limb. Avulsion type root injuries may damage the cervical spinal cord. Whether abnormal function of an upper limb affected by BPBP has any observable effects on the development of the locomotion system and overall motor function has not been clarified in depth. A total of 111 patients who had undergone brachial plexus surgery for BPBP in infancy were examined after a mean follow-up time of 13 (5-32) years. Patients' physical activities were recorded by a questionnaire. No significant inequalities in leg length were found and the incidence of structural scoliosis (1.7%) did not differ from that of the reference population. Nearly half of the patients (43%) had asynchronous motion of the upper limbs during gait, which was associated with impaired upper limb function. Data obtained from the completed questionnaires indicated that only few patients were unable to participate in normal activities such as: bicycling, cross-country skiing or swimming. Not surprisingly, 71% of the patients reported problems related to the affected upper limb, such as muscle weakness and/or joint stiffness during the aforementioned activities.

  19. Dose-dependent effects of extracted microcystins on embryonic development, larval growth and histopathological changes of southern catfish (Silurus meridionalis).

    Science.gov (United States)

    Zhang, Xuezhen; Xie, Ping; Wang, Weimin; Li, Dapeng; Li, Li; Tang, Rong; Lei, Hehua; Shi, Zechao

    2008-03-01

    A laboratory toxic experiment was conducted to examine dose-dependent effects of extracted microcystins (MCs) on embryonic development, larval growth and histopathological changes of southern catfish (Silurus meridionalis). Fertilized eggs were incubated in solutions with four concentrations of MCs (0, 1, 10, 100 microg MC-L Req l(-1)). Higher MCs retarded egg development (2-10h delays) and larval growth, reduced hatching rate (up to 45%), and caused high malformation rate (up to 15%) and hepatocytes damage (characterized by disorganization of cell structure and a loss of adherence between hepatocytes, cellular degeneration with vacuolar hepatocytes and marginal nuclei, even hepatocellular necrosis). A 10 microg MC-L Req l(-1) is close to a high concentration in natural cyanobacterial blooms, suggesting a possible existence of such toxic effects in eutrophic waters.

  20. C. elegans MRP-5 Exports Vitamin B12 from Mother to Offspring to Support Embryonic Development.

    Science.gov (United States)

    Na, Huimin; Ponomarova, Olga; Giese, Gabrielle E; Walhout, Albertha J M

    2018-03-20

    Vitamin B12 functions as a cofactor for methionine synthase to produce the anabolic methyl donor S-adenosylmethionine (SAM) and for methylmalonyl-CoA mutase to catabolize the short-chain fatty acid propionate. In the nematode Caenorhabditis elegans, maternally supplied vitamin B12 is required for the development of offspring. However, the mechanism for exporting vitamin B12 from the mother to the offspring is not yet known. Here, we use RNAi of more than 200 transporters with a vitamin B12-sensor transgene to identify the ABC transporter MRP-5 as a candidate vitamin B12 exporter. We show that the injection of vitamin B12 into the gonad of mrp-5 deficient mothers rescues embryonic lethality in the offspring. Altogether, our findings identify a maternal mechanism for the transit of an essential vitamin to support the development of the next generation. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  1. Niche-dependent development of functional neuronal networks from embryonic stem cell-derived neural populations

    Directory of Open Access Journals (Sweden)

    Siebler Mario

    2009-08-01

    Full Text Available Abstract Background The present work was performed to investigate the ability of two different embryonic stem (ES cell-derived neural precursor populations to generate functional neuronal networks in vitro. The first ES cell-derived neural precursor population was cultivated as free-floating neural aggregates which are known to form a developmental niche comprising different types of neural cells, including neural precursor cells (NPCs, progenitor cells and even further matured cells. This niche provides by itself a variety of different growth factors and extracellular matrix proteins that influence the proliferation and differentiation of neural precursor and progenitor cells. The second population was cultivated adherently in monolayer cultures to control most stringently the extracellular environment. This population comprises highly homogeneous NPCs which are supposed to represent an attractive way to provide well-defined neuronal progeny. However, the ability of these different ES cell-derived immature neural cell populations to generate functional neuronal networks has not been assessed so far. Results While both precursor populations were shown to differentiate into sufficient quantities of mature NeuN+ neurons that also express GABA or vesicular-glutamate-transporter-2 (vGlut2, only aggregate-derived neuronal populations exhibited a synchronously oscillating network activity 2–4 weeks after initiating the differentiation as detected by the microelectrode array technology. Neurons derived from homogeneous NPCs within monolayer cultures did merely show uncorrelated spiking activity even when differentiated for up to 12 weeks. We demonstrated that these neurons exhibited sparsely ramified neurites and an embryonic vGlut2 distribution suggesting an inhibited terminal neuronal maturation. In comparison, neurons derived from heterogeneous populations within neural aggregates appeared as fully mature with a dense neurite network and punctuated

  2. Embryonic development of four species of palaemonid prawns (Crustacea, Decapoda: pre-naupliar, naupliar and post-naupliar periods

    Directory of Open Access Journals (Sweden)

    Yara Müller

    2004-03-01

    Full Text Available The embryonic development of four species of the family Palaemonidae was studied under laboratory conditions. Adults of Macrobrachium olfersi (Wiegman, 1836, Macrobrachium potiuna (Müller, 1880, Palaemon pandaliformis (Stimpson, 1871 and Palaemonetes argentinus (Nobili, 1901 were collected in Santa Catarina Island, Santa Catarina, Brazil and maintained at 26ºC. The following embryonic characters were analyzed: egg shape, yolk organization and cleavage plane, naupliar and post-naupliar appendages, stomodeum, optical lobes, eyes, telson, embryo curvature and the space occupied by the embryo in the egg. Different rates of development were observed for the four species, with M. potiuna showing the longest time of embryogenesis. The species studied followed the pattern of embryogenesis of centrolecithal eggs, enabling the identification of similar features of the development, and the establishment of eight common embryonic stages.Foi estudado o desenvolvimento embrionário de quatro espécies de Palaemonidae em condições controladas de laboratório. Adultos de Macrobrachium olfersi (Wiegman, 1836, Macrobrachium potiuna (Müller, 1880, Palaemon pandaliformis (Stimpson, 1871 e Palaemonetes argentinus (Nobili, 1901 foram coletados na Ilha de Santa Catarina, SC, Brasil e mantidos à temperatura de 26ºC. Foram analisadas as seguintes características embrionárias: forma do ovo, organização do vitelo e planos de clivagem, apêndices naupliares e pós-naupliares, estomodeo, lobos ópticos, olhos, telson, curvatura do embrião e o espaço ocupado pelo embrião no ovo. Diferentes ritmos de desenvolvimento foram observados espécies, sendo que M. potiuna mostrou o maior tempo de embriogênese. As espécies seguem o padrão de embriogênese de ovos centrolécitos, sendo identificadas características similares do desenvolvimento, possibilitando o estabelecimento de oito estágios embrionários, comuns as quatro espécies.

  3. Porcine embryonic stem cells

    DEFF Research Database (Denmark)

    Hall, Vanessa Jane

    2008-01-01

    The development of porcine embryonic stem cell lines (pESC) has received renewed interest given the advances being made in the production of immunocompatible transgenic pigs. However, difficulties are evident in the production of pESCs in-vitro. This may largely be attributable to differences...

  4. Effect of divergent selection for uterine capacity on embryonic survival and development at 30 h post-mating in unilaterally ovariectomized rabbit females

    Directory of Open Access Journals (Sweden)

    R. Peiro

    2015-12-01

    Full Text Available Uterine capacity has been proposed as an indirect way to increase litter size. The aim of this work is to study the effect of a divergent selection for uterine capacity (UC on reproductive traits at 30 h post mating in unilaterally ovariectomized (ULO females. A total of 62 ULO females from the high line (selected to increase UC and 39 ULO females from the low line (selected to decrease UC were used. Ovulation rate was estimated as the number of corpora haemorrhagica and early embryonic survival was estimated as the ratio between number of embryos and ovulation rate. No differences in ovulation rate and early embryonic survival at 30 h post mating were found between high and low lines. Selection for UC did not change the embryonic stage of development either, the majority of embryos being at 4-cell stage. Additionally, the embryos were evaluated according to morphological criteria and more than 95% of the embryos were evaluated as good or fair quality. No differences in embryonic morphological criteria between high and low lines were found either. Thus, selection for UC did not modify the early embryonic survival and development in ULO females at 30 h post mating.

  5. Recent advances in the study of limb development: the emergence and function of the apical ectodermal ridge.

    Science.gov (United States)

    Rodriguez-Leon, Joaquin; Tomas, Ana Raquel; Johnson, Austin; Kawakami, Yasuhiko

    2013-01-01

    Vertebrate extremities develop from limb buds, which emerge as paired protrusions in the lateral plate mesoderm. Forelimb buds are located anteriorly and hindlimb buds are positioned posteriorly. The morphogenesis of the limb requires coordinated actions of several organizing centers, among which the apical ectodermal ridge (AER) plays crucial roles in limb development. Recent studies have shown how the life of the AER (induction, maturation, maintenance and regression) is regulated. This regulation includes cell type- and process- specific roles of previously identified molecules, such as fibroblast growth factors (FGFs), Wnts and bone morphogenetic proteins (BMPs). The studies have also revealed several new players, such as Arid3b, R-Spondin 2 and Flrt3. These advances have enhanced the understanding of how the AER is regulated from its emergence to its regression. Progress has also been made in understanding AER function in relation to processes critical for limb development: proximal-distal patterning, anterior-posterior patterning, chondrogenesis and apoptosis. By focusing on two major model systems, chick and mouse embryos, we will review recent advances in combination with relevant previous studies in the development and function of the AER.

  6. Glucocorticoids suppress beta-cell development and induce hepatic metaplasia in embryonic pancreas.

    Science.gov (United States)

    Shen, Chia-Ning; Seckl, Jonathan R; Slack, Jonathan M W; Tosh, David

    2003-10-01

    Elevated glucocorticoids are associated with low birth weight and fetal 'programming' of hypertension and glucose intolerance. In the present paper, we show that treatment of fetal rats with dexamethasone during the last week of gestation reduces the insulin content of their pancreatic beta-cells. We reproduce this effect of dexamethasone in vitro using organ cultures of mouse embryonic pancreas, and show that it is associated with an elevation of expression of the transcription factor C/EBPbeta (CCAAT/enhancer-binding protein beta) and a reduction of the transcription factor Pdx-1 (pancreatic duodenal homeobox-1). Dexamethasone also induces the appearance of hepatocyte-like cells in organ cultures of pancreas, based on the expression of liver markers, albumin, alpha1-antitrypsin and transthyretin. Evidence that C/EBPbeta is responsible for compromising the differentiation and later function of beta-cells is obtained from its effects on the beta-cell-like cell line RIN-5F. Transfection with a constitutive form of C/EBPb suppresses insulin formation, whereas introduction of a dominant-negative inhibitor of C/EBPb has no effect. We conclude that dexamethasone inhibits insulin expression in pancreatic beta-cells via a mechanism involving down-regulation of Pdx-1 and induction of C/EBPbeta. This mechanism may operate in combination with other changes during fetal programming, leading to type 2 diabetes in later life.

  7. Genetic background and embryonic temperature affect DNA methylation and expression of myogenin and muscle development in Atlantic salmon (Salmo salar.

    Directory of Open Access Journals (Sweden)

    Erik Burgerhout

    Full Text Available The development of ectothermic embryos is strongly affected by incubation temperature, and thermal imprinting of body growth and muscle phenotype has been reported in various teleost fishes. The complex epigenetic regulation of muscle development in vertebrates involves DNA methylation of the myogenin promoter. Body growth is a heritable and highly variable trait among fish populations that allows for local adaptations, but also for selective breeding. Here we studied the epigenetic effects of embryonic temperature and genetic background on body growth, muscle cellularity and myogenin expression in farmed Atlantic salmon (Salmo salar. Eggs from salmon families with either high or low estimated breeding values for body growth, referred to as Fast and Slow genotypes, were incubated at 8°C or 4°C until the embryonic 'eyed-stage' followed by rearing at the production temperature of 8°C. Rearing temperature strongly affected the growth rates, and the 8°C fish were about twice as heavy as the 4°C fish in the order Fast8>Slow8>Fast4>Slow4 prior to seawater transfer. Fast8 was the largest fish also at harvest despite strong growth compensation in the low temperature groups. Larval myogenin expression was approximately 4-6 fold higher in the Fast8 group than in the other groups and was associated with relative low DNA methylation levels, but was positively correlated with the expression levels of the DNA methyltransferase genes dnmt1, dnmt3a and dnmt3b. Juvenile Fast8 fish displayed thicker white muscle fibres than Fast4 fish, while Slow 8 and Slow 4 showed no difference in muscle cellularity. The impact of genetic background on the thermal imprinting of body growth and muscle development in Atlantic salmon suggests that epigenetic variation might play a significant role in the local adaptation to fluctuating temperatures over short evolutionary time.

  8. Genetic background and embryonic temperature affect DNA methylation and expression of myogenin and muscle development in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Burgerhout, Erik; Mommens, Maren; Johnsen, Hanne; Aunsmo, Arnfinn; Santi, Nina; Andersen, Øivind

    2017-01-01

    The development of ectothermic embryos is strongly affected by incubation temperature, and thermal imprinting of body growth and muscle phenotype has been reported in various teleost fishes. The complex epigenetic regulation of muscle development in vertebrates involves DNA methylation of the myogenin promoter. Body growth is a heritable and highly variable trait among fish populations that allows for local adaptations, but also for selective breeding. Here we studied the epigenetic effects of embryonic temperature and genetic background on body growth, muscle cellularity and myogenin expression in farmed Atlantic salmon (Salmo salar). Eggs from salmon families with either high or low estimated breeding values for body growth, referred to as Fast and Slow genotypes, were incubated at 8°C or 4°C until the embryonic 'eyed-stage' followed by rearing at the production temperature of 8°C. Rearing temperature strongly affected the growth rates, and the 8°C fish were about twice as heavy as the 4°C fish in the order Fast8>Slow8>Fast4>Slow4 prior to seawater transfer. Fast8 was the largest fish also at harvest despite strong growth compensation in the low temperature groups. Larval myogenin expression was approximately 4-6 fold higher in the Fast8 group than in the other groups and was associated with relative low DNA methylation levels, but was positively correlated with the expression levels of the DNA methyltransferase genes dnmt1, dnmt3a and dnmt3b. Juvenile Fast8 fish displayed thicker white muscle fibres than Fast4 fish, while Slow 8 and Slow 4 showed no difference in muscle cellularity. The impact of genetic background on the thermal imprinting of body growth and muscle development in Atlantic salmon suggests that epigenetic variation might play a significant role in the local adaptation to fluctuating temperatures over short evolutionary time.

  9. In ovo temperature manipulation differentially influences limb musculoskeletal development in two lines of chick embryos selected for divergent growth rates.

    Science.gov (United States)

    Al-Musawi, Sara L; Stickland, Neil C; Bayol, Stéphanie A M

    2012-05-01

    Selective breeding has led to diverging phenotypic evolution in layer and broiler chickens through genomic and epigenetic modifications. Here we show that in ovo environmental manipulation differentially influences embryonic limb muscle phenotype in these two breeds. We demonstrate that raising incubation temperature from 37.5 to 38.5°C between embryonic days (ED) 4 and 7 increased motility and body mass in both layer and broiler embryos. In layers, this was accompanied by gastrocnemius muscle hypertrophy, increased fibre and nuclei numbers and a higher nuclei to fibre ratio (ED18), preceded by increased hindlimb Myf5 (ED5-8), Pax7 (ED5-10), BMP4 (ED6-9) and IGF-I (ED9-10, ED18) mRNAs. In broilers, the same temperature treatment led to reduced gastrocnemius cross-sectional area with fewer fibres and nuclei and an unchanged fibre to nuclei ratio (ED18). This was preceded by a delay in the peak of hindlimb Myf5 expression, increased Pax7 (ED5, ED7-10) and BMP4 (ED6-8) but reduced IGF-I (ED8-10) mRNAs. Rather than promoting myogenesis as in layer embryos, the temperature treatment promoted gastrocnemius intramuscular fat deposition in broilers (ED18) preceded by increased hindlimb PPARγ mRNA (ED7-10). The treatment increased tibia/tarsus bone length as well as femur cross-sectional area in both breeds, but femur length and bone to cartilage ratio in the femur and tibia/tarsus were only increased in treated layers (ED18). We conclude that in ovo temperature manipulation differentially affected the molecular regulation of hindlimb myogenic, adipogenic and growth factor expression in broiler and layer embryos, leading to differential changes in muscle phenotype. The underlying interactive mechanisms between genes and the environment need further investigation.

  10. Development of subliminal persuasion system to improve the upper limb posture in laparoscopic training: a preliminary study.

    Science.gov (United States)

    Zhang, Di; Sessa, Salvatore; Kong, Weisheng; Cosentino, Sarah; Magistro, Daniele; Ishii, Hiroyuki; Zecca, Massimiliano; Takanishi, Atsuo

    2015-11-01

    Current training for laparoscopy focuses only on the enhancement of manual skill and does not give advice on improving trainees' posture. However, a poor posture can result in increased static muscle loading, faster fatigue, and impaired psychomotor task performance. In this paper, the authors propose a method, named subliminal persuasion, which gives the trainee real-time advice for correcting the upper limb posture during laparoscopic training like the expert but leads to a lower increment in the workload. A 9-axis inertial measurement unit was used to compute the upper limb posture, and a Detection Reaction Time device was developed and used to measure the workload. A monitor displayed not only images from laparoscope, but also a visual stimulus, a transparent red cross superimposed to the laparoscopic images, when the trainee had incorrect upper limb posture. One group was exposed, when their posture was not correct during training, to a short (about 33 ms) subliminal visual stimulus. The control group instead was exposed to longer (about 660 ms) supraliminal visual stimuli. We found that subliminal visual stimulation is a valid method to improve trainees' upper limb posture during laparoscopic training. Moreover, the additional workload required for subconscious processing of subliminal visual stimuli is less than the one required for supraliminal visual stimuli, which is processed instead at the conscious level. We propose subliminal persuasion as a method to give subconscious real-time stimuli to improve upper limb posture during laparoscopic training. Its effectiveness and efficiency were confirmed against supraliminal stimuli transmitted at the conscious level: Subliminal persuasion improved upper limb posture of trainees, with a smaller increase on the overall workload.

  11. Molecular phylogeny of Myriapoda provides insights into evolutionary patterns of the mode in post-embryonic development

    Science.gov (United States)

    Miyazawa, Hideyuki; Ueda, Chiaki; Yahata, Kensuke; Su, Zhi-Hui

    2014-01-01

    Myriapoda, a subphylum of Arthropoda, comprises four classes, Chilopoda, Diplopoda, Pauropoda, and Symphyla. While recent molecular evidence has shown that Myriapoda is monophyletic, the internal phylogeny, which is pivotal for understanding the evolutionary history of myriapods, remains unresolved. Here we report the results of phylogenetic analyses and estimations of divergence time and ancestral state of myriapods. Phylogenetic analyses were performed based on three nuclear protein-coding genes determined from 19 myriapods representing the four classes (17 orders) and 11 outgroup species. The results revealed that Symphyla whose phylogenetic position has long been debated is the sister lineage to all other myriapods, and that the interordinal relationships within classes were consistent with traditional classifications. Ancestral state estimation based on the tree topology suggests that myriapods evolved from an ancestral state that was characterized by a hemianamorphic mode of post-embryonic development and had a relatively low number of body segments and legs. PMID:24535281

  12. Editor's Highlight: Development of Novel Neural Embryonic Stem CellTests for High-Throughput Screening of Embryotoxic Chemicals.

    Science.gov (United States)

    Kobayashi, Kumiko; Suzuki, Noriyuki; Higashi, Kiyoshi; Muroi, Akane; Le Coz, Florian; Nagahori, Hirohisa; Saito, Koichi

    2017-09-01

    There is a great demand for appropriate alternative methods to rapidly evaluate the developmental and reproductive toxicity of a wide variety of chemicals. We used the differentiation of mouse embryonic stem cells (mESCs) into cardiomyocytes as a basis for establishing a rapid and highly reproducible invitro embryotoxicity test known as the Hand1-Luc Embryonic Stem Cell Test (Hand1-Luc EST). In this study, we developed novel neural-Luc ESTs using two marker genes for neural development, tubulin beta-3 (Tubb3) and Reelin (Reln), and evaluated the capacity of these tests to predict developmental toxicity. In addition, we tested whether an integrated approach (a combination of neural-Luc ESTs and the Hand1-Luc EST) improved developmental toxicant detection. To perform our neural-Luc ESTs, we needed to generate stable transgenic mESCs with individual promoters linked to the luciferase gene, and to establish that similar changes in promoter activities and mRNA expression levels occur during neural differentiation. Based on the concentration-response curves of 15 developmental toxicants and 17 non-developmental toxic chemicals, we derived a prediction formula and assessed the capacity of this formula to predict developmental toxicity. Although both were highly sensitive and specific for predicting developmental toxicity, neural-Luc ESTs had similar predictive capacities. In contrast, neural-Luc ESTs and Hand1-Luc EST had significantly different predictive powers. As expected, the combination of these ESTs increased the sensitivity of developmental toxicant detection. These results demonstrate the convenience and the usefulness of this combination of ESTs as an alternative assay system for future toxicological and mechanistic studies of developmental toxicity. © 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.

  13. Study on development of active-passive rehabilitation system for upper limbs: Hybrid-PLEMO

    International Nuclear Information System (INIS)

    Kikuchi, T; Jin, Y; Fukushima, K; Akai, H; Furusho, J

    2009-01-01

    In recent years, many researchers have studied the potential of using robotics technology to assist and quantify the motor functions for neuron-rehabilitation. Some kinds of haptic devices have been developed and evaluated its efficiency with clinical tests, for example, upper limb training for patients with spasticity after stroke. Active-type (motor-driven) haptic devices can realize a lot of varieties of haptics. But they basically require high-cost safety system. On the other hand, passive-type (brake-based) haptic devices have inherent safety. However, the passive robot system has strong limitation on varieties of haptics. There are not sufficient evidences to clarify how the passive/active haptics effect to the rehabilitation of motor skills. In this paper, we developed an active-passive-switchable rehabilitation system with ER clutch/brake device named 'Hybrid-PLEMO' in order to address these problems. In this paper, basic structures and haptic control methods of the Hybrid-PLEMO are described.

  14. Study on development of active-passive rehabilitation system for upper limbs: Hybrid-PLEMO

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, T; Jin, Y; Fukushima, K; Akai, H; Furusho, J [Department of Mechanical Engineering, Graduate School of Engineering, Osaka University, Osaka (Japan)], E-mail: kikuchi@mech.eng.osaka-u.ac.jp

    2009-02-01

    In recent years, many researchers have studied the potential of using robotics technology to assist and quantify the motor functions for neuron-rehabilitation. Some kinds of haptic devices have been developed and evaluated its efficiency with clinical tests, for example, upper limb training for patients with spasticity after stroke. Active-type (motor-driven) haptic devices can realize a lot of varieties of haptics. But they basically require high-cost safety system. On the other hand, passive-type (brake-based) haptic devices have inherent safety. However, the passive robot system has strong limitation on varieties of haptics. There are not sufficient evidences to clarify how the passive/active haptics effect to the rehabilitation of motor skills. In this paper, we developed an active-passive-switchable rehabilitation system with ER clutch/brake device named 'Hybrid-PLEMO' in order to address these problems. In this paper, basic structures and haptic control methods of the Hybrid-PLEMO are described.

  15. Brain machine interface and limb reanimation technologies: restoring function after spinal cord injury through development of a bypass system.

    Science.gov (United States)

    Lobel, Darlene A; Lee, Kendall H

    2014-05-01

    Functional restoration of limb movement after traumatic spinal cord injury (SCI) remains the ultimate goal in SCI treatment and directs the focus of current research strategies. To date, most investigations in the treatment of SCI focus on repairing the injury site. Although offering some promise, these efforts have met with significant roadblocks because treatment measures that are successful in animal trials do not yield similar results in human trials. In contrast to biologic therapies, there are now emerging neural interface technologies, such as brain machine interface (BMI) and limb reanimation through electrical stimulators, to create a bypass around the site of the SCI. The BMI systems analyze brain signals to allow control of devices that are used to assist SCI patients. Such devices may include a computer, robotic arm, or exoskeleton. Limb reanimation technologies, which include functional electrical stimulation, epidural stimulation, and intraspinal microstimulation systems, activate neuronal pathways below the level of the SCI. We present a concise review of recent advances in the BMI and limb reanimation technologies that provides the foundation for the development of a bypass system to improve functional outcome after traumatic SCI. We also discuss challenges to the practical implementation of such a bypass system in both these developing fields. Copyright © 2014 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  16. Clustering of Tissue-Specific Sub-TADs Accompanies the Regulation of HoxA Genes in Developing Limbs

    Science.gov (United States)

    Berlivet, Soizik; Paquette, Denis; Dumouchel, Annie; Langlais, David; Dostie, Josée; Kmita, Marie

    2013-01-01

    HoxA genes exhibit central roles during development and causal mutations have been found in several human syndromes including limb malformation. Despite their importance, information on how these genes are regulated is lacking. Here, we report on the first identification of bona fide transcriptional enhancers controlling HoxA genes in developing limbs and show that these enhancers are grouped into distinct topological domains at the sub-megabase scale (sub-TADs). We provide evidence that target genes and regulatory elements physically interact with each other through contacts between sub-TADs rather than by the formation of discreet “DNA loops”. Interestingly, there is no obvious relationship between the functional domains of the enhancers within the limb and how they are partitioned among the topological domains, suggesting that sub-TAD formation does not rely on enhancer activity. Moreover, we show that suppressing the transcriptional activity of enhancers does not abrogate their contacts with HoxA genes. Based on these data, we propose a model whereby chromatin architecture defines the functional landscapes of enhancers. From an evolutionary standpoint, our data points to the convergent evolution of HoxA and HoxD regulation in the fin-to-limb transition, one of the major morphological innovations in vertebrates. PMID:24385922

  17. Clustering of tissue-specific sub-TADs accompanies the regulation of HoxA genes in developing limbs.

    Directory of Open Access Journals (Sweden)

    Soizik Berlivet

    Full Text Available HoxA genes exhibit central roles during development and causal mutations have been found in several human syndromes including limb malformation. Despite their importance, information on how these genes are regulated is lacking. Here, we report on the first identification of bona fide transcriptional enhancers controlling HoxA genes in developing limbs and show that these enhancers are grouped into distinct topological domains at the sub-megabase scale (sub-TADs. We provide evidence that target genes and regulatory elements physically interact with each other through contacts between sub-TADs rather than by the formation of discreet "DNA loops". Interestingly, there is no obvious relationship between the functional domains of the enhancers within the limb and how they are partitioned among the topological domains, suggesting that sub-TAD formation does not rely on enhancer activity. Moreover, we show that suppressing the transcriptional activity of enhancers does not abrogate their contacts with HoxA genes. Based on these data, we propose a model whereby chromatin architecture defines the functional landscapes of enhancers. From an evolutionary standpoint, our data points to the convergent evolution of HoxA and HoxD regulation in the fin-to-limb transition, one of the major morphological innovations in vertebrates.

  18. Virtual reality imaging techniques in the study of embryonic and early placental health.

    Science.gov (United States)

    Rousian, Melek; Koster, Maria P H; Mulders, Annemarie G M G J; Koning, Anton H J; Steegers-Theunissen, Régine P M; Steegers, Eric A P

    2018-04-01

    Embryonic and placental growth and development in the first trimester of pregnancy have impact on the health of the fetus, newborn, child and even the adult. This emphasizes the importance of this often neglected period in life. The development of three-dimensional transvaginal ultrasonography in combination with virtual reality (VR) opens the possibility of accurate and reliable visualization of embryonic and placental structures with real depth perception. These techniques enable new biometry and volumetry measurements that contribute to the knowledge of the (patho)physiology of embryonic and early placental health. Examples of such measurements are the length of complex structures like the umbilical cord, vitelline duct, limbs and cerebellum or the volume of the whole embryo and brain cavities. Moreover, for the first time, embryos can now be staged in vivo (Carnegie stages) and vasculature volumes of both the embryo and the early placenta can be measured when VR is combined with power Doppler signals. These innovative developments have already been used to study associations between periconceptional maternal factors, such as age, smoking, alcohol use, diet and vitamin status, and embryonic and early placental growth and development. Future studies will also focus on the identification of abnormal embryonic and early placental development already in the earliest weeks of pregnancy, which provides opportunities for early prevention of pregnancy complications. Copyright © 2018 IFPA, Elsevier Ltd. Published by Elsevier Ltd.. All rights reserved.

  19. Effect of silver nanoparticles on Mediterranean sea urchin embryonal development is species specific and depends on moment of first exposure.

    Science.gov (United States)

    Burić, Petra; Jakšić, Željko; Štajner, Lara; Dutour Sikirić, Maja; Jurašin, Darija; Cascio, Claudia; Calzolai, Luigi; Lyons, Daniel Mark

    2015-10-01

    With the ever growing use of nanoparticles in a broad range of industrial and consumer applications there is increasing likelihood that such nanoparticles will enter the aquatic environment and be transported through freshwater systems, eventually reaching estuarine or marine waters. Due to silver's known antimicrobial properties and widespread use of silver nanoparticles (AgNP), their environmental fate and impact is therefore of particular concern. In this context we have investigated the species-specific effects of low concentrations of 60 nm AgNP on embryonal development in Mediterranean sea urchins Arbacia lixula, Paracentrotus lividus and Sphaerechinus granularis. The sensitivity of urchin embryos was tested by exposing embryos to nanoparticle concentrations in the 1-100 μg L(-1) range, with times of exposure varying from 30 min to 24 h (1 h-48 h for S. granularis) post-fertilisation which corresponded with fertilized egg, 4 cell, blastula and gastrula development phases. The most sensitive species to AgNP was A. lixula with significant modulation of embryonal development at the lowest AgNP concentrations of 1-10 μg L(-1) with high numbers of malformed embryos or arrested development. The greatest impact on development was noted for those embryos first exposed to nanoparticles at 6 and 24 h post fertilisation. For P. lividus, similar effects were noted at higher concentrations of 50 μg L(-1) and 100 μg L(-1) for all times of first exposure. The S. granularis embryos indicated a moderate AgNP impact, and significant developmental abnormalities were recorded in the concentration range of 10-50 μg L(-1). As later post-fertilisation exposure times to AgNP caused greater developmental changes in spite of a shorter total exposure time led us to postulate on additional mechanisms of AgNP toxicity. The results herein indicate that toxic effects of AgNP are species-specific. The moment at which embryos first encounter AgNP is also shown to be

  20. Development and reliability of the rating of compensatory movements in upper limb prosthesis wearers during work-related tasks.

    Science.gov (United States)

    van der Laan, Tallie M J; Postema, Sietke G; Reneman, Michiel F; Bongers, Raoul M; van der Sluis, Corry K

    2018-02-10

    Reliability study. Quantifying compensatory movements during work-related tasks may help to prevent musculoskeletal complaints in individuals with upper limb absence. (1) To develop a qualitative scoring system for rating compensatory shoulder and trunk movements in upper limb prosthesis wearers during the performance of functional capacity evaluation tests adjusted for use by 1-handed individuals (functional capacity evaluation-one handed [FCE-OH]); (2) to examine the interrater and intrarater reliability of the scoring system; and (3) to assess its feasibility. Movement patterns of 12 videotaped upper limb prosthesis wearers and 20 controls were analyzed. Compensatory movements were defined for each FCE-OH test, and a scoring system was developed, pilot tested, and adjusted. During reliability testing, 18 raters (12 FCE experts and 6 physiotherapists/gait analysts) scored videotapes of upper limb prosthesis wearers performing 4 FCE-OH tests 2 times (2 weeks apart). Agreement was expressed in % and kappa value. Feasibility (focus area's "acceptability", "demand," and "implementation") was determined by using a questionnaire. After 2 rounds of pilot testing and adjusting, reliability of a third version was tested. The interrater reliability for the first and second rating sessions were к = 0.54 (confidence interval [CI]: 0.52-0.57) and к = 0.64 (CI: 0.61-0.66), respectively. The intrarater reliability was к = 0.77 (CI: 0.72-0.82). The feasibility was good but could be improved by a training program. It seems possible to identify compensatory movements in upper limb prosthesis wearers during the performance of FCE-OH tests reliably by observation using the developed observational scoring system. Interrater reliability was satisfactory in most instances; intrarater reliability was good. Feasibility was established. Copyright © 2018 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  1. Dynamic expression of N-myc in mouse embryonic development using an enhanced green fluorescent protein reporter gene in the N-myc locus.

    Science.gov (United States)

    Ma, Ming; Zhao, Kai; Wu, Wenting; Sun, Ruilin; Fei, Jian

    2014-02-01

    N-myc belongs to the Myc oncogene family and plays an essential role in mammalian embryonic development. The expression of N-myc is dynamically regulated during embryonic development; however, its expression pattern has not been well characterized due to the lack of a suitable animal model. In this paper, a genetically modified mouse model was generated in which the enhanced green fluorescent protein (EGFP) coding sequence was inserted into the N-myc locus, so that endogenous N-myc expression could be traced by the signal of EGFP. The EGFP signal in the transgenic mouse was confirmed to be consistent with the expression pattern of endogenous N-myc by fluorescence microscopy and immunohistochemical staining. Furthermore, the spatial and temporal expression of EGFP was observed in the central and peripheral nervous system, heart, lung and kidney, given the known indispensable role of N-myc in their formation. EGFP was also strongly detected in the liver, paranephros and the epithelium of the intestine. The EGFP signal can be used to trace N-myc expression in this transgenic mouse model. N-myc expression was observed in specific locations and cell lineages, and dynamically changed during embryonic development. The changing N-myc expression pattern seen in mouse embryonic development and the animal model described in this paper provide important insights and a new tool to research N-myc function. © 2014 The Authors Development, Growth & Differentiation © 2014 Japanese Society of Developmental Biologists.

  2. Loss of ribosomal protein L11 affects zebrafish embryonic development through a p53-dependent apoptotic response.

    Directory of Open Access Journals (Sweden)

    Anirban Chakraborty

    Full Text Available Ribosome is responsible for protein synthesis in all organisms and ribosomal proteins (RPs play important roles in the formation of a functional ribosome. L11 was recently shown to regulate p53 activity through a direct binding with MDM2 and abrogating the MDM2-induced p53 degradation in response to ribosomal stress. However, the studies were performed in cell lines and the significance of this tumor suppressor function of L11 has yet to be explored in animal models. To investigate the effects of the deletion of L11 and its physiological relevance to p53 activity, we knocked down the rpl11 gene in zebrafish and analyzed the p53 response. Contrary to the cell line-based results, our data indicate that an L11 deficiency in a model organism activates the p53 pathway. The L11-deficient embryos (morphants displayed developmental abnormalities primarily in the brain, leading to embryonic lethality within 6-7 days post fertilization. Extensive apoptosis was observed in the head region of the morphants, thus correlating the morphological defects with apparent cell death. A decrease in total abundance of genes involved in neural patterning of the brain was observed in the morphants, suggesting a reduction in neural progenitor cells. Upregulation of the genes involved in the p53 pathway were observed in the morphants. Simultaneous knockdown of the p53 gene rescued the developmental defects and apoptosis in the morphants. These results suggest that ribosomal dysfunction due to the loss of L11 activates a p53-dependent checkpoint response to prevent improper embryonic development.

  3. Development of a Biofeedback Therapeutic Exercise Supporting Manipulator for Lower Limbs

    Science.gov (United States)

    Hashimoto, Yosuke; Hisada, Takashi; Komada, Satoshi; Hirai, Junji

    Although equipments that support physical therapy have been developed, there are few types of equipment to improve quality of physical therapy. This paper proposes a new concept of robotic biofeedback exercise equipment that displays human muscle force during training. The concept tries to have therapeutic value through grasping of condition for trainee during exercise and giving an incentive to perform training. The equipment is not only for convalescent patients but also for athletes and healthy persons with a physical trouble. The manipulator is designed to support lower limb rehabilitation of knee and hip joints in sagittal plane, where a 3-degrees-of-freedom manipulator is adopted in order to realize low height equipment. Since the manipulator has redundant degree of freedom, collision avoidance is performed by a controller based on acceleration control by disturbance observer. Moreover, simultaneous isokinetic movement for knee and hip joints that has an adjustment capability of maximum speed and time constant is realized in order to perform safe training by isokinetic muscular contraction. Desired motion is realized experimentally by the proposed manipulator.

  4. Regulation of wingless signaling by the CKI family in Drosophila limb development.

    Science.gov (United States)

    Zhang, Lei; Jia, Jianhang; Wang, Bing; Amanai, Kazuhito; Wharton, Keith A; Jiang, Jin

    2006-11-01

    The Wingless (Wg)/Wnt signaling pathway regulates a myriad of developmental processes and its malfunction leads to human disorders including cancer. Recent studies suggest that casein kinase I (CKI) family members play pivotal roles in the Wg/Wnt pathway. However, genetic evidence for the involvement of CKI family members in physiological Wg/Wnt signaling events is lacking. In addition, there are conflicting reports regarding whether a given CKI family member functions as a positive or negative regulator of the pathway. Here we examine the roles of seven CKI family members in Wg signaling during Drosophila limb development. We find that increased CKIepsilon stimulates whereas dominant-negative or a null CKIepsilon mutation inhibits Wg signaling. In contrast, inactivation of CKIalpha by RNA interference (RNAi) leads to ectopic Wg signaling. Interestingly, hypomorphic CKIepsilon mutations synergize with CKIalpha RNAi to induce ectopic Wg signaling, revealing a negative role for CKIepsilon. Conversely, CKIalpha RNAi enhances the loss-of-Wg phenotypes caused by CKIepsilon null mutation, suggesting a positive role for CKIalpha. While none of the other five CKI isoforms can substitute for CKIalpha in its inhibitory role in the Wg pathway, several CKI isoforms including CG12147 exhibit a positive role based on overexpression. Moreover, loss of Gilgamesh (Gish)/CKIgamma attenuates Wg signaling activity. Finally, we provide evidence that several CKI isoforms including CKIalpha and Gish/CKIgamma can phosphorylate the Wg coreceptor Arrow (Arr), which may account, at least in part, for their positive roles in the Wg pathway.

  5. Embryonic epithelial membrane transporters.

    Science.gov (United States)

    Horster, M

    2000-12-01

    Embryonic epithelial membrane transporters are organized into transporter families that are functional in several epithelial organs, namely, in kidney, lung, pancreas, intestine, and salivary gland. Family members (subtypes) are developmentally expressed in plasma membranes in temporospatial patterns that are 1) similar for one subtype within different organs, like aquaporin-1 (AQP1) in lung and kidney; 2) different between subtypes within the same organ, like the amiloride-sensitive epithelial sodium channel (ENaC) in lung; and 3) apparently matched among members of different transporter families, as alpha-ENaC with AQP1 and -4 in lung and with AQP2 in kidney. Finally, comparison of temporal expression patterns in early embryonic development of transporters from different families [e.g., cystic fibrosis transmembrane conductance regulator (CFTR), ENaC, and outer medullary potassium channel] suggests regulatory activating or inactivating interactions in defined morphogenic periods. This review focuses on embryonic patterns, at the mRNA and immunoprotein level, of the following transporter entities expressed in epithelial cell plasma membranes: ENaC; the chloride transporters CFTR, ClC-2, bumetanide-sensitive Na-K-Cl cotransporter, Cl/OH, and Cl/HCO(3); the sodium glucose transporter-glucose transporter; the sodium/hydrogen exchanger; the sodium-phosphate cotransporter; the ATPases; and AQP. The purpose of this article is to relate temporal and spatial expression patterns in embryonic and in early postnatal epithelia to developmental changes in organ structure and function.

  6. A lower limb assessment tool for athletes at risk of developing patellar tendinopathy.

    Science.gov (United States)

    Mann, Kerry J; Edwards, Suzi; Drinkwater, Eric J; Bird, Stephen P

    2013-03-01

    Patellar tendon abnormality (PTA) on diagnostic imaging is part of the diagnostic criteria for patellar tendinopathy. PTA and altered landing strategies are primary risk factors that increase the likelihood of asymptomatic athletes developing patellar tendinopathy. Therefore, the aim of this study was to examine the risk factors that are predictors of the presence and severity of a PTA in junior pre-elite athletes. Ten junior pre-elite male basketball athletes with a PTA were matched with 10 athletes with normal patellar tendons. Participants had patellar tendon morphology, Victorian Institute of Sport Assessment (VISA) score, body composition, lower limb flexibility, and maximum vertical jump height measured before performing five successful stop-jump tasks. During each stop-jump task, both two-dimensional and three-dimensional kinematics and ground reaction forces were recorded. Multiple regression analyses were used to identify factors for estimating PTA presence and severity, and discriminate analysis was used to classify PTA presence. Sixty-eight percent of variance for presence of a PTA was accounted for by hip joint range of motion (ROM) and knee joint angle at initial foot-ground contact (IC) during stop-jump task and quadriceps flexibility, whereas hip joint ROM during stop-jump task and VISA score accounted for 62% of variance for PTA severity. Prediction of the presence of a PTA was achieved with 95% accuracy and 95% cross-validation. An easily implemented, reliable, and valid movement screening tool composed of three criteria enables coaches and/or clinicians to predict the presence and severity of a PTA in asymptomatic athletes. This enables identification of asymptomatic athletes at higher risk of developing patellar tendinopathy, which allows the development of effective preventative measures to aid in the reduction of patellar tendinopathy injury prevalence.

  7. Identification of microRNAs controlling hepatic mRNA levels for metabolic genes during the metabolic transition from embryonic to posthatch development in the chicken.

    Science.gov (United States)

    Hicks, Julie A; Porter, Tom E; Liu, Hsiao-Ching

    2017-09-05

    The transition from embryonic to posthatch development in the chicken represents a massive metabolic switch from primarily lipolytic to primarily lipogenic metabolism. This metabolic switch is essential for the chick to successfully transition from the metabolism of stored egg yolk to the utilization of carbohydrate-based feed. However, regulation of this metabolic switch is not well understood. We hypothesized that microRNAs (miRNAs) play an important role in the metabolic switch that is essential to efficient growth of chickens. We used high-throughput RNA sequencing to characterize expression profiles of mRNA and miRNA in liver during late embryonic and early posthatch development of the chicken. This extensive data set was used to define the contributions of microRNAs to the metabolic switch during development that is critical to growth and nutrient utilization in chickens. We found that expression of over 800 mRNAs and 30 miRNAs was altered in the embryonic liver between embryonic day 18 and posthatch day 3, and many of these differentially expressed mRNAs and miRNAs are associated with metabolic processes. We confirmed the regulation of some of these mRNAs by miRNAs expressed in a reciprocal pattern using luciferase reporter assays. Finally, through the use of yeast one-hybrid screens, we identified several proteins that likely regulate expression of one of these important miRNAs. Integration of the upstream regulatory mechanisms governing miRNA expression along with monitoring the downstream effects of this expression will ultimately allow for the construction of complete miRNA regulatory networks associated with the hepatic metabolic switch in chickens. Our findings support a key role for miRNAs in controlling the metabolic switch that occurs between embryonic and posthatch development in the chicken.

  8. Maternal N-Carbamylglutamate Supplementation during Early Pregnancy Enhances Embryonic Survival and Development through Modulation of the Endometrial Proteome in Gilts.

    Science.gov (United States)

    Zhu, Jinlong; Zeng, Xiangfang; Peng, Qian; Zeng, Shenming; Zhao, Haiyi; Shen, Hexiao; Qiao, Shiyan

    2015-10-01

    Early pregnancy loss is a major concern in humans and animals. N-carbamylglutamate (NCG) has been found to enhance embryonic survival during early pregnancy in rats. However, little is known about the key factors in the endometrium involved in the improvement of embryonic implantation and development induced by maternal NCG supplementation. Our objectives were to investigate whether NCG supplementation during early gestation enhanced embryonic survival and development in gilts and to uncover the related factors using the approach of endometrium proteome analysis with isobaric tags for relative and absolute quantification (iTRAQ). Uteruses and embryos/fetuses were obtained on days 14 and 28 of gestation from gilts fed a basal diet that was or was not supplemented with 0.05% NCG. The iTRAQ-based quantitative proteomics approach was performed to explore the endometrium proteome altered by NCG supplementation. Maternal NCG supplementation significantly increased the number of total fetuses and live fetuses on day 28 of gestation by 1.32 and 1.29, respectively (P gilts. The differentially expressed proteins primarily are involved in cell adhesion, energy metabolism, lipid metabolism, protein metabolism, antioxidative stress, and immune response. On day 14 of gestation, several proteins closely related to embryonic implantation and development, such as integrin-αv, integrin-β3, talin, and endothelial nitric oxide synthase, were upregulated (3.7-, 4.1-, 2.4-, and 5.4-fold increases, respectively) by NCG supplementation. To our knowledge, our results provide the first evidence that altered abundance of the endometrial proteome induced by NCG supplementation is highly associated with the improvement of embryonic survival and development in gilts. © 2015 American Society for Nutrition.

  9. Inactivating the spindle checkpoint kinase Bub1 during embryonic development results in a global shutdown of proliferation

    Directory of Open Access Journals (Sweden)

    Taylor Stephen S

    2009-09-01

    Full Text Available Abstract Background Bub1 is a component of the spindle assembly checkpoint, a surveillance mechanism that maintains chromosome stability during M-phase. Bub1 is essential during the early stages of embryogenesis, with homozygous BUB1-null mice dying shortly after day E3.5. Bub1 is also required later during embryogenesis; inactivation of BUB1 on day E10.5 appears to rapidly block all further development. However, the mechanism(s responsible for this phenotype remain unclear. Findings Here we show that inactivating BUB1 on day E10.5 stalls embryogenesis within 48 hours. This is accompanied by a global shutdown of proliferation, widespread apoptosis and haemorrhaging. Conclusion Our results suggest that Bub1 is required throughout the developing embryo for cellular proliferation. Therefore, Bub1 has been shown to be essential in all scenarios analyzed thus far in mice: proliferation of cultured fibroblasts, spermatogenesis, oogenesis and both early and late embryonic development. This likely reflects the fact that Bub1 has dual functions during mitosis, being required for both SAC function and chromosome alignment.

  10. Post-embryonic development in the mite suborder Opilioacarida, with notes on segmental homology in Parasitiformes (Arachnida).

    Science.gov (United States)

    Klompen, Hans; Vázquez, Ma Magdalena; Bernardi, Leopoldo Ferreira de Oliveira

    2015-10-01

    In order to study homology among the major lineages of the mite (super)order Parasitiformes, developmental patterns in Opilioacarida are documented, emphasizing morphology of the earliest, post-embryonic instars. Developmental patterns are summarized for all external body structures, based on examination of material in four different genera. Development includes an egg, a 6-legged prelarva and larva, three 8-legged nymphal instars, and the adults, for the most complete ontogenetic sequence in Parasitiformes. The prelarva and larva appear to be non-feeding. Examination of cuticular structures over ontogeny allows development of an updated model for body segmentation and sensillar distribution patterns in Opilioacarida. This model includes a body made up of a well-developed ocular segment plus at most 17 additional segments. In the larvae and protonymphs each segment may carry up to six pairs of sensilla (setae or lyrifissures) arranged is distinct series (J, Z, S, Sv, Zv, Jv). The post-protonymphal instars add two more series (R and Rv) but no extra segments. This basic model is compatible with sensillar patterns in other Parasitiformes, leading to the hypothesis that all taxa in that (super)order may have the same segmental ground plan. The substantial segmental distortion implied in the model can be explained using a single process involving differential growth in the coxal regions of all appendage-bearing segments.

  11. Changes in the fat body during the post-embryonic development of the predator Toxorhynchites theobaldi (Dyar & Knab) (Diptera: Culicidae).

    Science.gov (United States)

    Pascini, T V; Albeny, D S; Ramalho-Ortigão, M; Vilela, E F; Serrão, J E; Martins, G F

    2011-01-01

    Several studies have focused on understanding the biochemistry and morphology of the fat body of the hematophagous mosquito Aedes aegypti (L.) (Diptera: Culicidae). In contrast, few studies, if any, have focused on morphological characters of the fat body in other mosquitoes, especially non-hematophagous taxa such as the culicid Toxorhynchites. Larvae of Toxorhynchites prey upon the larvae of other mosquito species and are used in vector mosquito control. We investigated aspects of the fat body trophocytes, including the morphometric analyses of the lipid droplets, protein granules and nuclei, during Toxorhynchites theobaldi (Dyar & Knab) post-embryonic development. Following the body weight increase from larval stage L2 to L4, the size of lipid droplets within the trophocytes also increase, and are likely the result of lipogenesis. Lipid droplets decrease in size during L4 to the female pupal stage and increase once again during the period from newly-emerged to mature adult females. Protein granules are observed for the first time in female pupae, and their appearance might be related to protein storage during metamorphosis. The size of the nucleus of trophocytes also increases during larval development, followed by a decrease during metamorphosis and an additional increase as adult female ages. In conclusion, the morphology of the fat body of T. theobaldi changes according to the developmental stage. Our study provides for the first time important insights into T. theobaldi fat body development and contributes to understand this species biology.

  12. Development of heart muscle-cell diversity: a help or a hindrance for phenotyping embryonic stem cell-derived cardiomyocytes

    NARCIS (Netherlands)

    Fijnvandraat, Arnoud C.; Lekanne Deprez, Ronald H.; Moorman, Antoon F. M.

    2003-01-01

    Despite the advances in cardiovascular treatment, cardiac disease remains a major cause of morbidity in all industrialized countries. The extraordinary potential of (embryonic) stem cells for therapeutic purposes has revolutionized ideas about cardiac repair of diseased cardiac muscle to exciting

  13. Studies on improving ostrich egg hatch ability and its relation with some factors affecting embryonic development during artificial incubation

    International Nuclear Information System (INIS)

    Amer, N.S.I.

    2012-01-01

    The present study was carried out in co-operation between the Ostrich Production Farm, Nuclear Research Center, Atomic Energy Authority, Cairo, Egypt and the Faculty of Agriculture, AL-Azhar University, Nasr City, Cairo, Egypt. Ostrich eggs were obtained from Resk Company for Ostrich Production and set for incubation at ElShfie Farm, Belbas, Sharkia, Egypt. The objectives are:1- To follow up changes in some vital physiological parameters and blood components associated with ostrich embryonic development during incubation and to provide reference blood biochemical baseline values for future studies of avian species and to document novel information on some normal changes associated with growth of the developing ostrich embryo during the incubation, as no similar and complete data could be found on this aspect in the literature. 2- In an effort to improve the hatch ability and hatching performance of ostrich eggs by testing the effect of in ovo injection of several nutrients. Two trials were carried out: 1-First trial To follow up changes in some vital physiological parameters and blood components associated with ostrich embryonic development during incubation. A total number of 60 ostrich eggs weighed between 1300 and 1500 g were obtained from from Resk Company for Ostrich Production. Eggs were collected weekly in patches of 25 eggs and Egg incubation was performed in ElShfie Farm, Belbas, Egypt. Egg weight and egg weight loss during incubation were determined on each eggs.2- Second Trial In vivo injection In an effort to improve the hatch ability and hatching performance of ostrich eggs by testing the effect of in ovo injection of several nutrients. A total of 100 fertile ostrich eggs weighed between 1300 and 1500 g were obtained from from Resk Company for Ostrich Production. Eggs were collected weekly in patches of 25 eggs and egg incubation was performed in ElShfie Farm, Belbas, Egypt. Eggs were injected at the 7 th day of incubation to deposit test material in

  14. Sarcomagenesis and myofibril maturation during limb regeneration and development of the newt, Triturus alpestris and salamander, Salamandra salamandra.

    Science.gov (United States)

    Kilarski, W; Kozlowska, M

    1980-01-01

    During limb regeneration of the salamander, Salamandra salamandra, muscles dedifferentiate and then mesenchymal cells appear, which subsequently, differentiate into muscle. Both in regenerates and in developing limbs of newts larvae mesenchymal cells begin to differentiate into myoblasts, which contain both thin (7 nm) and thick (14 nm) filaments, which are often associated with microtubules, developing a cytoskeletal network, which contribute directly to the shape of myoblasts and a linear alignment of the myofibrils. Both thin and thick filaments appear as a tandem near the periphery of the myoblasts, where myofibrilogenesis occurs. In the early stage of sarcomagenesis the appearance of "Z-bodies" was observed. They were intimately associated with the tandem of filaments thus forming the primary sarcomere units. Consequently the "Z-bodies" coalesce to form primitive Z-lines. The maturation of the primary sarcomeres occurs during fibrilogenesis and is manifested by the gradual thining of the Z-line and thickening of the M-line.

  15. Single cell analysis of caspase-3 in apoptotic and non-apoptotic cells during mouse limb development

    Czech Academy of Sciences Publication Activity Database

    Adamová, Eva; Klepárník, Karel; Matalová, E.

    2014-01-01

    Roč. 3, - (2014), PP58 ISSN 2052-1219. [European Calcified Tissue Society Congress /41./. 17.05.2014-20.05.2014, Praha] R&D Projects: GA ČR GAP206/11/2377; GA ČR(CZ) GA14-28254S Institutional support: RVO:68081715 Keywords : single cell analysis * caspase-3 * mouse limb development Subject RIV: CB - Analytical Chemistry, Separation

  16. Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development.

    Science.gov (United States)

    Krishnamurthy, Vishnu V; Turgeon, Aurora J; Khamo, John S; Mondal, Payel; Sharum, Savanna R; Mei, Wenyan; Yang, Jing; Zhang, Kai

    2017-06-15

    Kinase activity is crucial for a plethora of cellular functions, including cell proliferation, differentiation, migration, and apoptosis. During early embryonic development, kinase activity is highly dynamic and widespread across the embryo. Pharmacological and genetic approaches are commonly used to probe kinase activities. Unfortunately, it is challenging to achieve superior spatial and temporal resolution using these strategies. Furthermore, it is not feasible to control the kinase activity in a reversible fashion in live cells and multicellular organisms. Such a limitation remains a bottleneck for achieving a quantitative understanding of kinase activity during development and differentiation. This work presents an optogenetic strategy that takes advantage of a bicistronic system containing photoactivatable proteins Arabidopsis thaliana cryptochrome 2 (CRY2) and the N-terminal domain of cryptochrome-interacting basic-helix-loop-helix (CIBN). Reversible activation of the mitogen-activated protein kinase (MAPK) signaling pathway is achieved through light-mediated protein translocation in live cells. This approach can be applied to mammalian cell cultures and live vertebrate embryos. This bicistronic system can be generalized to control the activity of other kinases with similar activation mechanisms and can be applied to other model systems.

  17. Tetrodotoxin concentrations within a clutch and across embryonic development in eggs of the rough-skinned newts (Taricha granulosa).

    Science.gov (United States)

    Gall, Brian G; Stokes, Amber N; Pett, Jory J; Spivey, Kari L; French, Susannah S; Brodie, Edmund D; Brodie, Edmund D

    2014-11-01

    Tetrodotoxin is an enigmatic neurotoxin that is found in a wide-variety of organisms. Unfortunately, tetrodotoxin (TTX) toxicity across life-history stages is poorly understood in most organisms. Rough-skinned newts (Taricha granulosa) possess the greatest known quantities of TTX of any organism and numerous studies have begun to elucidate these patterns in this species. We conducted a series of studies to answer the following questions: (1) do eggs from a single female's clutch vary in toxicity? (2) does TTX concentration change during embryonic development? and (3) does the jelly coat from newt eggs possess TTX? We found that the amount of TTX in newt eggs depended on the relative "position" of the egg within a clutch; eggs deposited at the beginning of the clutch had substantially more TTX than those at the end. During development egg toxicity remained consistent until hatching. The jelly coat contained small quantities of TTX, but these were not correlated with the toxicity of the embryo. These results clarify several long-held interpretations about embryo toxicity and continue to elucidate the life-history patterns of tetrodotoxin toxicity in this amphibian. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Embryonic and larvae development of reciprocal crosses between Pangasianodon hypophthalmus (Sauvage, 1878 and Clarias gariepinus (Burchell, 1822

    Directory of Open Access Journals (Sweden)

    V.T. Okomoda

    2017-12-01

    Full Text Available The egg and larval development of reciprocal crosses of Pangasianodon hypophthalmus (Sauvage, 1878 and Clarias gariepinus (Burchell, 1822 were studied under laboratory conditions. Crosses between ♀C. gariepinus × ♂P. hypophthalmus (Clariothalmus and ♀P. hypophthalmus × ♂C. gariepinus (Pangapinus had embryonic stages similar to those of the pure sib, however, unequal cell cleavages were notable in the early development of both crosses, hence, leading to different forms of deformities. The critical stage where highest mortality occurred during the embryogenesis was the somite (21.68% and hatching (48.1% stages (respectively for the Clariothalmus and Pangapinus. However, both crosses produced viable larvae (60.21 vs 13.20% hatchability respectively, which survived (30.3 vs 2.1% respectively until the end of the study (2 weeks. The external morphological features of the larvae were completely formed by the 14th day after hatching. The body forms of the crosses at this time were either phenotypic intermediary of the parent species (92% of Clariothalmus or indistinguishable from the female parent (all Pangapinus and 8% of the Clariothalmus. This study thus laid the groundwork for further comparative studies on hybrid performance and characterization.

  19. Achievement report for fiscal 1999 on research and development of technologies for medical welfare equipment. Rehabilitation system for upper limbs and lower limbs; 1999 nendo iryo fukushi kiki gijutsu kenkyu kaihatsu seika hokokusho. Shintai kino rihabiri shien system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-05-01

    This project aims to develop physical function measuring and training systems equipped with a variety of feedback utilities and widely applicable to the prevention of the elderly from physical function degradation, to the preservation of physical functions, and to their recovery from mild physical difficulties, thereby helping the elderly enjoy independence and participation in social activities. Possibilities will be studied of providing them with engineering support in the field of exercise therapy through the analysis of the characteristics of old people's movement, and the findings will be applied to the designing and assessment of welfare and nursing equipment and also fed back to their development environment. In the gait training system, the suspension force is adjusted according to data from the force plate and various position sensors, and the system produces an effect similar to that of walking in the water. The lower limb rehabilitation system facilitates the treatment of the aged or handicapped people, and patients suffering from cerebral disorders, at any of their physical positions from lying to standing. The upper limb training support system is to provide motivation for the aged or handicapped people suffering from mild difficulties in their upper limbs. In this fiscal year, basic designs have been prepared for the gait training system and the lower limb rehabilitation system, and a preparatory survey is conducted for the upper limb training support system. (NEDO)

  20. Anatomical Network Comparison of Human Upper and Lower, Newborn and Adult, and Normal and Abnormal Limbs, with Notes on Development, Pathology and Limb Serial Homology vs. Homoplasy.

    Science.gov (United States)

    Diogo, Rui; Esteve-Altava, Borja; Smith, Christopher; Boughner, Julia C; Rasskin-Gutman, Diego

    2015-01-01

    How do the various anatomical parts (modules) of the animal body evolve into very different integrated forms (integration) yet still function properly without decreasing the individual's survival? This long-standing question remains unanswered for multiple reasons, including lack of consensus about conceptual definitions and approaches, as well as a reasonable bias toward the study of hard tissues over soft tissues. A major difficulty concerns the non-trivial technical hurdles of addressing this problem, specifically the lack of quantitative tools to quantify and compare variation across multiple disparate anatomical parts and tissue types. In this paper we apply for the first time a powerful new quantitative tool, Anatomical Network Analysis (AnNA), to examine and compare in detail the musculoskeletal modularity and integration of normal and abnormal human upper and lower limbs. In contrast to other morphological methods, the strength of AnNA is that it allows efficient and direct empirical comparisons among body parts with even vastly different architectures (e.g. upper and lower limbs) and diverse or complex tissue composition (e.g. bones, cartilages and muscles), by quantifying the spatial organization of these parts-their topological patterns relative to each other-using tools borrowed from network theory. Our results reveal similarities between the skeletal networks of the normal newborn/adult upper limb vs. lower limb, with exception to the shoulder vs. pelvis. However, when muscles are included, the overall musculoskeletal network organization of the upper limb is strikingly different from that of the lower limb, particularly that of the more proximal structures of each limb. Importantly, the obtained data provide further evidence to be added to the vast amount of paleontological, gross anatomical, developmental, molecular and embryological data recently obtained that contradicts the long-standing dogma that the upper and lower limbs are serial homologues