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Sample records for early mammalian development

  1. Cell fate regulation in early mammalian development

    NASA Astrophysics Data System (ADS)

    Oron, Efrat; Ivanova, Natalia

    2012-08-01

    Preimplantation development in mammals encompasses a period from fertilization to implantation and results in formation of a blastocyst composed of three distinct cell lineages: epiblast, trophectoderm and primitive endoderm. The epiblast gives rise to the organism, while the trophectoderm and the primitive endoderm contribute to extraembryonic tissues that support embryo development after implantation. In many vertebrates, such as frog or fish, maternally supplied lineage determinants are partitioned within the egg. Cell cleavage that follows fertilization results in polarization of these factors between the individual blastomeres, which become restricted in their developmental fate. In contrast, the mouse oocyte and zygote lack clear polarity and, until the eight-cell stage, individual blastomeres retain the potential to form all lineages. How are cell lineages specified in the absence of a maternally supplied blueprint? This is a fundamental question in the field of developmental biology. The answer to this question lies in understanding the cell-cell interactions and gene networks involved in embryonic development prior to implantation and using this knowledge to create testable models of the developmental processes that govern cell fates. We provide an overview of classic and contemporary models of early lineage development in the mouse and discuss the emerging body of work that highlights similarities and differences between blastocyst development in the mouse and other mammalian species.

  2. Studies toward birth and early mammalian development in space

    NASA Astrophysics Data System (ADS)

    Ronca, April E.

    2003-10-01

    Sustaining life beyond Earth on either space stations or other planets will require a clear understanding of how the space environment affects key phases of mammalian reproduction and development. Pregnancy, parturition (birth) and the early development of offspring are complex processes essential for successful reproduction and the proliferation of mammalian species. While no mammal has yet undergone birth within the space environment, studies spanning the gravity continuum from 0- to 2-g are revealing startling insights into how reproduction and development may proceed under gravitational conditions deviating from those typically experienced on Earth. In this report, I review studies of pregnant Norway rats and their offspring flown in microgravity (μg) onboard the NASA Space Shuttle throughout the period corresponding to mid- to late gestation, and analogous studies of pregnant rats exposed to hypergravity ( ht) onboard the NASA Ames Research Center 24-ft centrifuge. Studies of postnatal rats flown in space or exposed to centrifugation are reviewed. Although many important questions remain unanswered, the available data suggest that numerous aspects of pregnancy, birth and early mammalian development can proceed under altered gravity conditions. Published by Elsevier Ltd on behalf of COSPAR.

  3. Studies Toward Birth and Early Mammalian Development in Space

    NASA Technical Reports Server (NTRS)

    Ronca, April E.; Dalton, Bonnie (Technical Monitor)

    2002-01-01

    Successful reproduction is the hallmark of a species' ability to adapt to its environment and must be realized to sustain life beyond Earth. Before taking this immense step, we need to understand the effects of altered gravity on critical phases of mammalian reproduction, viz., those events surrounding pregnancy, birth and the early development of offspring. No mammal has yet undergone birth in space. however studies spanning the gravity continuum from 0 to 2-g are revealing insights into how birth and early postnatal development will proceed in space. In this presentation, I will report the results of behavioral studies of rat mothers and offspring exposed from mid- to late pregnancy to either hypogravity (0-g) or hypergravity (1.5 or 2-g).

  4. Effects of Gravity, Microgravity or Microgravity Simulation on Early Mammalian Development.

    PubMed

    Ruden, Douglas M; Bolnick, Alan; Awonuga, Awoniyi; Abdulhasan, Mohammed; Perez, Gloria; Puscheck, Elizabeth E; Rappolee, Daniel A

    2018-06-11

    Plant and animal life forms evolved mechanisms for sensing and responding to gravity on Earth where homeostatic needs require responses. The lack of gravity, such as in the International Space Station (ISS), causes acute, intra-generational changes in the quality of life. These include maintaining calcium levels in bone, maintaining muscle tone, and disturbances in the vestibular apparatus in the ears. These problems decrease work efficiency and quality of life of humans not only during microgravity exposures but also after return to higher gravity on Earth or destinations such as Mars or the Moon. It has been hypothesized that lack of gravity during mammalian development may cause prenatal, postnatal and transgenerational effects that conflict with the environment, especially if the developing organism and its progeny are returned, or introduced de novo, into the varied gravity environments mentioned above. Although chicken and frog pregastrulation development, and plant root development, have profound effects due to orientation of cues by gravity-sensing mechanisms and responses, mammalian development is not typically characterized as gravity-sensing. Although no effects of microgravity simulation (MGS) on mouse fertilization were observed in two reports, negative effects of MGS on early mammalian development after fertilization and before gastrulation are presented in four reports that vary with the modality of MGS. This review will analyze the positive and negative mammalian early developmental outcomes, and enzymatic and epigenetic mechanisms known to mediate developmental responses to simulated microgravity on Earth and microgravity during spaceflight experiments. We will update experimental techniques that have already been developed or need to be developed for zero gravity molecular, cellular, and developmental biology experiments.

  5. Mammalian development in space

    NASA Technical Reports Server (NTRS)

    Ronca, April E.

    2003-01-01

    Life on Earth, and thus the reproductive and ontogenetic processes of all extant species and their ancestors, evolved under the constant influence of the Earth's l g gravitational field. These considerations raise important questions about the ability of mammals to reproduce and develop in space. In this chapter, I review the current state of our knowledge of spaceflight effects on developing mammals. Recent studies are revealing the first insights into how the space environment affects critical phases of mammalian reproduction and development, viz., those events surrounding fertilization, embryogenesis, pregnancy, birth, postnatal maturation and parental care. This review emphasizes fetal and early postnatal life, the developmental epochs for which the greatest amounts of mammalian spaceflight data have been amassed. The maternal-offspring system, the coordinated aggregate of mother and young comprising mammalian development, is of primary importance during these early, formative developmental phases. The existing research supports the view that biologically meaningful interactions between mothers and offspring are changed in the weightlessness of space. These changes may, in turn, cloud interpretations of spaceflight effects on developing offspring. Whereas studies of mid-pregnant rats in space have been extraordinarily successful, studies of young rat litters launched at 9 days of postnatal age or earlier, have been encumbered with problems related to the design of in-flight caging and compromised maternal-offspring interactions. Possibilities for mammalian birth in space, an event that has not yet transpired, are considered. In the aggregate, the results indicate a strong need for new studies of mammalian reproduction and development in space. Habitat development and systematic ground-based testing are important prerequisites to future research with young postnatal rodents in space. Together, the findings support the view that the environment within which young

  6. Metabolic plasticity during mammalian development is directionally dependent on early nutritional status.

    PubMed

    Gluckman, Peter D; Lillycrop, Karen A; Vickers, Mark H; Pleasants, Anthony B; Phillips, Emma S; Beedle, Alan S; Burdge, Graham C; Hanson, Mark A

    2007-07-31

    Developmental plasticity in response to environmental cues can take the form of polyphenism, as for the discrete morphs of some insects, or of an apparently continuous spectrum of phenotype, as for most mammalian traits. The metabolic phenotype of adult rats, including the propensity to obesity, hyperinsulinemia, and hyperphagia, shows plasticity in response to prenatal nutrition and to neonatal administration of the adipokine leptin. Here, we report that the effects of neonatal leptin on hepatic gene expression and epigenetic status in adulthood are directionally dependent on the animal's nutritional status in utero. These results demonstrate that, during mammalian development, the direction of the response to one cue can be determined by previous exposure to another, suggesting the potential for a discontinuous distribution of environmentally induced phenotypes, analogous to the phenomenon of polyphenism.

  7. Mammalian Target of Rapamycin: Its Role in Early Neural Development and in Adult and Aged Brain Function

    PubMed Central

    Garza-Lombó, Carla; Gonsebatt, María E.

    2016-01-01

    The kinase mammalian target of rapamycin (mTOR) integrates signals triggered by energy, stress, oxygen levels, and growth factors. It regulates ribosome biogenesis, mRNA translation, nutrient metabolism, and autophagy. mTOR participates in various functions of the brain, such as synaptic plasticity, adult neurogenesis, memory, and learning. mTOR is present during early neural development and participates in axon and dendrite development, neuron differentiation, and gliogenesis, among other processes. Furthermore, mTOR has been shown to modulate lifespan in multiple organisms. This protein is an important energy sensor that is present throughout our lifetime its role must be precisely described in order to develop therapeutic strategies and prevent diseases of the central nervous system. The aim of this review is to present our current understanding of the functions of mTOR in neural development, the adult brain and aging. PMID:27378854

  8. Importance of the pluripotency factor LIN28 in the mammalian nucleolus during early embryonic development.

    PubMed

    Vogt, Edgar J; Meglicki, Maciej; Hartung, Kristina Ilka; Borsuk, Ewa; Behr, Rüdiger

    2012-12-01

    The maternal nucleolus is required for proper activation of the embryonic genome (EGA) and early embryonic development. Nucleologenesis is characterized by the transformation of a nucleolar precursor body (NPB) to a mature nucleolus during preimplantation development. However, the function of NPBs and the involved molecular factors are unknown. We uncover a novel role for the pluripotency factor LIN28, the biological significance of which was previously demonstrated in the reprogramming of human somatic cells to induced pluripotent stem (iPS) cells. Here, we show that LIN28 accumulates at the NPB and the mature nucleolus in mouse preimplantation embryos and embryonic stem cells (ESCs), where it colocalizes with the nucleolar marker B23 (nucleophosmin 1). LIN28 has nucleolar localization in non-human primate (NHP) preimplantation embryos, but is cytoplasmic in NHP ESCs. Lin28 transcripts show a striking decline before mouse EGA, whereas LIN28 protein localizes to NPBs at the time of EGA. Following knockdown with a Lin28 morpholino, the majority of embryos arrest between the 2- and 4-cell stages and never develop to morula or blastocyst. Lin28 morpholino-injected embryos arrested at the 2-cell stage were not enriched with nucleophosmin at presumptive NPB sites, indicating that functional NPBs were not assembled. Based on these results, we propose that LIN28 is an essential factor of nucleologenesis during early embryonic development.

  9. Early mammalian development under conditions of reorientation relative to the gravity vector

    NASA Technical Reports Server (NTRS)

    Wolgemuth, D. J.; Grills, G. S.

    1985-01-01

    A clinostat was used to assess the effects of reorientation relative to the gravity vector on mammalian germ cells cultured in vitro. Previous studies using this system revealed an inhibition of meiotic maturation of mouse oocytes. In the present study, the effects of clinostat rotation on in vitro fertilization were examined. The frequency of fertilization of experimental cultures did not vary from that of the clinostat vertical control cultures at either of the rotation rates examined. Importantly, no abnormalities of fertilization, such as parthenogenetic activation, fragmentation, or polyspermy were seen. It is concluded that the initial events of fertilization were unaffected by this treatment, although the developmental potential of these embryos remains to be assessed.

  10. PreImplantation Factor (PIF) correlates with early mammalian embryo development-bovine and murine models

    PubMed Central

    2011-01-01

    Background PreImplantation Factor (PIF), a novel peptide secreted by viable embryos is essential for pregnancy: PIF modulates local immunity, promotes decidual pro-adhesion molecules and enhances trophoblast invasion. To determine the role of PIF in post-fertilization embryo development, we measured the peptide's concentration in the culture medium and tested endogenous PIF's potential trophic effects and direct interaction with the embryo. Methods Determine PIF levels in culture medium of multiple mouse and single bovine embryos cultured up to the blastocyst stage using PIF-ELISA. Examine the inhibitory effects of anti-PIF-monoclonal antibody (mAb) added to medium on cultured mouse embryos development. Test FITC-PIF uptake by cultured bovine blastocysts using fluorescent microscopy. Results PIF levels in mouse embryo culture medium significantly increased from the morula to the blastocyst stage (ANOVA, P = 0.01). In contrast, atretic embryos medium was similar to the medium only control. Detectable - though low - PIF levels were secreted already by 2-cell stage mouse embryos. In single bovine IVF-derived embryos, PIF levels in medium at day 3 of culture were higher than non-cleaving embryos (control) (P = 0.01) and at day 7 were higher than day 3 (P = 0.03). In non-cleaving embryos culture medium was similar to medium alone (control). Anti-PIF-mAb added to mouse embryo cultures lowered blastocyst formation rate 3-fold in a dose-dependent manner (2-way contingency table, multiple groups, X2; P = 0.01) as compared with non-specific mouse mAb, and medium alone, control. FITC-PIF was taken-up by cultured bovine blastocysts, but not by scrambled FITC-PIF (control). Conclusions PIF is an early embryo viability marker that has a direct supportive role on embryo development in culture. PIF-ELISA use to assess IVF embryo quality prior to transfer is warranted. Overall, our data supports PIF's endogenous self sustaining role in embryo development and the utility of PIF

  11. FOXL2 activates P450 aromatase gene transcription: towards a better characterization of the early steps of mammalian ovarian development.

    PubMed

    Pannetier, Maëlle; Fabre, Stéphane; Batista, Frank; Kocer, Ayhan; Renault, Lauriane; Jolivet, Geneviève; Mandon-Pépin, Béatrice; Cotinot, Corinne; Veitia, Reiner; Pailhoux, Eric

    2006-06-01

    Previous studies have equated FOXL2 as a crucial actor in the ovarian differentiation process in different vertebrate species. Its transcriptional extinction in the polled intersex syndrome (PIS) leads primarily to a drastic decrease of aromatase (CYP19) expression in the first steps of goat ovarian development. In this study, we provide a better characterization of early ovarian development in goat, and we provide experimental evidence demonstrating that FOXL2 represents a direct transcriptional activator of the CYP19 gene through its ovarian-specific promoter 2. Moreover, the ovarian location of FOXL2 and CYP19 proteins, together with their expression profiles in the female gonads, stress the involvement of FOXL2 co-factor(s) for regulating CYP19 transcription. Expressional analyses show that activin-betaA can be considered as a strong candidate for being one of these FOXL2 co-factors. Finally, we discuss evidence for a role of activin and estrogens in somatic and germinal cell proliferation occurring before germ cell meiosis. This period, of 20 days in goat, seems to have no equivalent in mouse. This species-specific difference could explain the phenotype discrepancy observed between XX goat PIS(-/-) and XX mouse Foxl2(-/-).

  12. Early development of the primordial mammalian diaphragm and cellular mechanisms of nitrofen-induced congenital diaphragmatic hernia.

    PubMed

    Clugston, Robin D; Zhang, Wei; Greer, John J

    2010-01-01

    Congenital diaphragmatic hernia (CDH) is a frequently occurring cause of neonatal respiratory distress and is associated with high mortality and long-term morbidity. Evidence from animal models suggests that CDH has its origins in the malformation of the pleuroperitoneal fold (PPF), a key structure in embryonic diaphragm formation. The aims of this study were to characterize the embryogenesis of the PPF in rats and humans, and to determine the potential mechanism that leads to abnormal PPF development in the nitrofen model of CDH. Analysis of rat embryos, and archived human embryo sections, allowed the timeframe of PPF formation to be determined for both species, thus delineating a critical period of diaphragm development in relation to CDH. Experiments on nitrofen-exposed NIH 3T3 cells in vitro led us to hypothesize that nitrofen might cause diaphragmatic hernia in vivo by two possible mechanisms: through decreased cell proliferation or by inducing apoptosis. Data from nitrofen-exposed rat embryos indicates that the primary mechanism of nitrofen teratogenesis in the PPF is through decreased cell proliferation. This study provides novel insight into the embryogenesis of the PPF in rats and humans, and it indicates that impaired cell proliferation might contribute to abnormal diaphragm development in the nitrofen model of CDH. Copyright 2009 Wiley-Liss, Inc.

  13. Mammalian oocyte growth and development in vitro.

    PubMed

    Eppig, J J; O'Brien, M; Wigglesworth, K

    1996-06-01

    This paper is a review of the current status of technology for mammalian oocyte growth and development in vitro. It compares and contrasts the characteristics of the various culture systems that have been devised for the culture of either isolated preantral follicles or the oocyte-granulosa cell complexes form preantral follicles. The advantages and disadvantages of these various systems are discussed. Endpoints for the evaluation of oocyte development in vitro, including oocyte maturation and embryogenesis, are described. Considerations for the improvement of the culture systems are also presented. These include discussions of the possible effects of apoptosis and inappropriate differentiation of oocyte-associated granulosa cells on oocyte development. Finally, the potential applications of the technology for oocyte growth and development in vitro are discussed. For example, studies of oocyte development in vitro could help to identify specific molecules produced during oocyte development that are essential for normal early embryogenesis and perhaps recognize defects leading to infertility or abnormalities in embryonic development. Moreover, the culture systems may provide the methods necessary to enlarge the populations of valuable agricultural, pharmaceutical product-producing, and endangered animals, and to rescue the oocytes of women about to undergo clinical procedures that place oocytes at risk.

  14. A shark antibody heavy chain encoded by a nonsomatically rearranged VDJ is preferentially expressed in early development and is convergent with mammalian IgG.

    PubMed

    Rumfelt, L L; Avila, D; Diaz, M; Bartl, S; McKinney, E C; Flajnik, M F

    2001-02-13

    In most vertebrate embryos and neonates studied to date unique antigen receptors (antibodies and T cell receptors) are expressed that possess a limited immune repertoire. We have isolated a subclass of IgM, IgM(1gj), from the nurse shark Ginglymostoma cirratum that is preferentially expressed in neonates. The variable (V) region gene encoding the heavy (H) chain underwent V-D-J rearrangement in germ cells ("germline-joined"). Such H chain V genes were discovered over 10 years ago in sharks but until now were not shown to be expressed at appreciable levels; we find expression of H(1gj) in primary and secondary lymphoid tissues early in life, but in adults only in primary lymphoid tissue, which is identified in this work as the epigonal organ. H(1gj) chain associates covalently with light (L) chains and is most similar in sequence to IgM H chains, but like mammalian IgG has three rather than the four IgM constant domains; deletion of the ancestral IgM C2 domain thus defines both IgG and IgM(1gj). Because sharks are the members of the oldest vertebrate class known to possess antibodies, unique or specialized antibodies expressed early in ontogeny in sharks and other vertebrates were likely present at the inception of the adaptive immune system.

  15. A shark antibody heavy chain encoded by a nonsomatically rearranged VDJ is preferentially expressed in early development and is convergent with mammalian IgG

    PubMed Central

    Rumfelt, Lynn L.; Avila, David; Diaz, Marilyn; Bartl, Simona; McKinney, E. Churchill; Flajnik, Martin F.

    2001-01-01

    In most vertebrate embryos and neonates studied to date unique antigen receptors (antibodies and T cell receptors) are expressed that possess a limited immune repertoire. We have isolated a subclass of IgM, IgM1gj, from the nurse shark Ginglymostoma cirratum that is preferentially expressed in neonates. The variable (V) region gene encoding the heavy (H) chain underwent V-D-J rearrangement in germ cells (“germline-joined”). Such H chain V genes were discovered over 10 years ago in sharks but until now were not shown to be expressed at appreciable levels; we find expression of H1gj in primary and secondary lymphoid tissues early in life, but in adults only in primary lymphoid tissue, which is identified in this work as the epigonal organ. H1gj chain associates covalently with light (L) chains and is most similar in sequence to IgM H chains, but like mammalian IgG has three rather than the four IgM constant domains; deletion of the ancestral IgM C2 domain thus defines both IgG and IgM1gj. Because sharks are the members of the oldest vertebrate class known to possess antibodies, unique or specialized antibodies expressed early in ontogeny in sharks and other vertebrates were likely present at the inception of the adaptive immune system. PMID:11172027

  16. Programmed cell senescence during mammalian embryonic development.

    PubMed

    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.

  17. Evolution and development of the mammalian cerebral cortex.

    PubMed

    Molnár, Zoltán; Kaas, Jon H; de Carlos, Juan A; Hevner, Robert F; Lein, Ed; Němec, Pavel

    2014-01-01

    Comparative developmental studies of the mammalian brain can identify key changes that can generate the diverse structures and functions of the brain. We have studied how the neocortex of early mammals became organized into functionally distinct areas, and how the current level of cortical cellular and laminar specialization arose from the simpler premammalian cortex. We demonstrate the neocortical organization in early mammals, which helps to elucidate how the large, complex human brain evolved from a long line of ancestors. The radial and tangential enlargement of the cortex was driven by changes in the patterns of cortical neurogenesis, including alterations in the proportions of distinct progenitor types. Some cortical cell populations travel to the cortex through tangential migration whereas others migrate radially. A number of recent studies have begun to characterize the chick, mouse and human and nonhuman primate cortical transcriptome to help us understand how gene expression relates to the development and anatomical and functional organization of the adult neocortex. Although all mammalian forms share the basic layout of cortical areas, the areal proportions and distributions are driven by distinct evolutionary pressures acting on sensory and motor experiences during the individual ontogenies. © 2014 S. Karger AG, Basel.

  18. The role of early development in mammalian limb diversification: a descriptive comparison of early limb development between the Natal long-fingered bat (Miniopterus natalensis) and the mouse (Mus musculus).

    PubMed

    Hockman, Dorit; Mason, Mandy K; Jacobs, David S; Illing, Nicola

    2009-04-01

    Comparative embryology expands our understanding of unique limb structures, such as that found in bats. Bat forelimb digits 2 to 5 are differentially elongated and joined by webbing, while the hindlimb digits are of similar length in many species. We compare limb development between the mouse and the Natal long-fingered bat, Miniopterus natalensis, to pinpoint the stage at which their limbs begin to differ. The bat forelimb differs from the mouse at Carollia stage (CS) 14 with the appearance of the wing membrane primordia. This difference is enhanced at CS 15 with the posterior expansion of the hand plate. The bat hindlimb begins to differ from the mouse between CS 15 and 16 when the foot plate undergoes a proximal expansion resulting in digit primordia of very similar length. Our findings support recent gene expression studies, which reveal a role for early patterning in the development of the bat limb. Copyright 2009 Wiley-Liss, Inc.

  19. Regulation of the Embryonic Cell Cycle During Mammalian Preimplantation Development.

    PubMed

    Palmer, N; Kaldis, P

    2016-01-01

    The preimplantation development stage of mammalian embryogenesis consists of a series of highly conserved, regulated, and predictable cell divisions. This process is essential to allow the rapid expansion and differentiation of a single-cell zygote into a multicellular blastocyst containing cells of multiple developmental lineages. This period of development, also known as the germinal stage, encompasses several important developmental transitions, which are accompanied by dramatic changes in cell cycle profiles and dynamics. These changes are driven primarily by differences in the establishment and enforcement of cell cycle checkpoints, which must be bypassed to facilitate the completion of essential cell cycle events. Much of the current knowledge in this area has been amassed through the study of knockout models in mice. These mouse models are powerful experimental tools, which have allowed us to dissect the relative dependence of the early embryonic cell cycles on various aspects of the cell cycle machinery and highlight the extent of functional redundancy between members of the same gene family. This chapter will explore the ways in which the cell cycle machinery, their accessory proteins, and their stimuli operate during mammalian preimplantation using mouse models as a reference and how this allows for the usually well-defined stages of the cell cycle to be shaped and transformed during this unique and critical stage of development. © 2016 Elsevier Inc. All rights reserved.

  20. Effects of simulated weightlessness on mammalian development. Part 1: Development of clinostat for mammalian tissue culture and use in studies on meiotic maturation of mouse oocytes

    NASA Technical Reports Server (NTRS)

    Wolegemuth, D. J.; Grills, G. S.

    1984-01-01

    The effects of weightlessness on three aspects of mammalian reproduction: oocyte development, fertilization, and early embryogenesis was studied. Zero-gravity conditions within the laboratory by construction of a clinostat designed to support in vitro tissue culture were simulated and the effects of simulated weightlessness on meiotic maturation in mammalian oocytes using mouse as the model system were studied. The timing and frequency of germinal vesicule breakdown and polar body extrusion, and the structural and numerical properties of meiotic chromosomes at Metaphase and Metaphase of meiosis are assessed.

  1. Wnt4 is essential to normal mammalian lung development.

    PubMed

    Caprioli, Arianna; Villasenor, Alethia; Wylie, Lyndsay A; Braitsch, Caitlin; Marty-Santos, Leilani; Barry, David; Karner, Courtney M; Fu, Stephen; Meadows, Stryder M; Carroll, Thomas J; Cleaver, Ondine

    2015-10-15

    Wnt signaling is essential to many events during organogenesis, including the development of the mammalian lung. The Wnt family member Wnt4 has been shown to be required for the development of kidney, gonads, thymus, mammary and pituitary glands. Here, we show that Wnt4 is critical for proper morphogenesis and growth of the respiratory system. Using in situ hybridization in mouse embryos, we identify a previously uncharacterized site of Wnt4 expression in the anterior trunk mesoderm. This expression domain initiates as early as E8.25 in the mesoderm abutting the tracheoesophageal endoderm, between the fusing dorsal aortae and the heart. Analysis of Wnt4(-/-) embryos reveals severe lung hypoplasia and tracheal abnormalities; however, aortic fusion and esophageal development are unaffected. We find decreased cell proliferation in Wnt4(-/-) lung buds, particularly in tip domains. In addition, we observe reduction of the important lung growth factors Fgf9, Fgf10, Sox9 and Wnt2 in the lung bud during early stages of organogenesis, as well as decreased tracheal expression of the progenitor factor Sox9. Together, these data reveal a previously unknown role for the secreted protein Wnt4 in respiratory system development. Copyright © 2015. Published by Elsevier Inc.

  2. Self-Organization of Stem Cell Colonies and of Early Mammalian Embryos: Recent Experiments Shed New Light on the Role of Autonomy vs. External Instructions in Basic Body Plan Development

    PubMed Central

    Denker, Hans-Werner

    2016-01-01

    “Organoids”, i.e., complex structures that can develop when pluripotent or multipotent stem cells are maintained in three-dimensional cultures, have become a new area of interest in stem cell research. Hopes have grown that when focussing experimentally on the mechanisms behind this type of in vitro morphogenesis, research aiming at tissue and organ replacements can be boosted. Processes leading to the formation of organoids in vitro are now often addressed as self-organization, a term referring to the formation of complex tissue architecture in groups of cells without depending on specific instruction provided by other cells or tissues. The present article focuses on recent reports using the term self-organization in the context of studies on embryogenesis, specifically addressing pattern formation processes in human blastocysts attaching in vitro, or in colonies of pluripotent stem cells (“gastruloids”). These morphogenetic processes are of particular interest because, during development in vivo, they lead to basic body plan formation and individuation. Since improved methodologies like those employed by the cited authors became available, early embryonic pattern formation/self-organization appears to evolve now as a research topic of its own. This review discusses concepts concerning the involved mechanisms, focussing on autonomy of basic body plan development vs. dependence on external signals, as possibly provided by implantation in the uterus, and it addresses biological differences between an early mammalian embryo, e.g., a morula, and a cluster of pluripotent stem cells. It is concluded that, apart from being of considerable biological interest, the described type of research needs to be contemplated carefully with regard to ethical implications when performed with human cells. PMID:27792143

  3. Self-Organization of Stem Cell Colonies and of Early Mammalian Embryos: Recent Experiments Shed New Light on the Role of Autonomy vs. External Instructions in Basic Body Plan Development.

    PubMed

    Denker, Hans-Werner

    2016-10-25

    " Organoids ", i.e., complex structures that can develop when pluripotent or multipotent stem cells are maintained in three-dimensional cultures, have become a new area of interest in stem cell research. Hopes have grown that when focussing experimentally on the mechanisms behind this type of in vitro morphogenesis, research aiming at tissue and organ replacements can be boosted. Processes leading to the formation of organoids in vitro are now often addressed as self-organization , a term referring to the formation of complex tissue architecture in groups of cells without depending on specific instruction provided by other cells or tissues. The present article focuses on recent reports using the term self-organization in the context of studies on embryogenesis , specifically addressing pattern formation processes in human blastocysts attaching in vitro, or in colonies of pluripotent stem cells (" gastruloids "). These morphogenetic processes are of particular interest because, during development in vivo, they lead to basic body plan formation and individuation. Since improved methodologies like those employed by the cited authors became available, early embryonic pattern formation/self-organization appears to evolve now as a research topic of its own. This review discusses concepts concerning the involved mechanisms, focussing on autonomy of basic body plan development vs. dependence on external signals, as possibly provided by implantation in the uterus, and it addresses biological differences between an early mammalian embryo, e.g., a morula, and a cluster of pluripotent stem cells. It is concluded that, apart from being of considerable biological interest, the described type of research needs to be contemplated carefully with regard to ethical implications when performed with human cells.

  4. The impact of transposable elements on mammalian development

    PubMed Central

    Garcia-Perez, Jose L.; Widmann, Thomas J.; Adams, Ian R.

    2018-01-01

    Summary Despite often being classified as selfish or junk DNA, transposable elements (TEs) are a group of abundant genetic sequences that significantly impact on mammalian development and genome regulation. In recent years, our understanding of how pre-existing TEs affect genome architecture, gene regulatory networks and protein function during mammalian embryogenesis has dramatically expanded. In addition, the mobilization of active TEs in selected cell types has been shown to generate genetic variation during development and in fully differentiated tissues. Importantly, the ongoing domestication and evolution of TEs appears to provide a rich source of regulatory elements, functional modules and genetic variation that fuels the evolution of mammalian developmental processes. Here, we review the functional impact that TEs exert on mammalian developmental processes and how the somatic activity of TEs can influence gene regulatory networks. PMID:27875251

  5. The impact of transposable elements on mammalian development.

    PubMed

    Garcia-Perez, Jose L; Widmann, Thomas J; Adams, Ian R

    2016-11-15

    Despite often being classified as selfish or junk DNA, transposable elements (TEs) are a group of abundant genetic sequences that have a significant impact on mammalian development and genome regulation. In recent years, our understanding of how pre-existing TEs affect genome architecture, gene regulatory networks and protein function during mammalian embryogenesis has dramatically expanded. In addition, the mobilization of active TEs in selected cell types has been shown to generate genetic variation during development and in fully differentiated tissues. Importantly, the ongoing domestication and evolution of TEs appears to provide a rich source of regulatory elements, functional modules and genetic variation that fuels the evolution of mammalian developmental processes. Here, we review the functional impact that TEs exert on mammalian developmental processes and discuss how the somatic activity of TEs can influence gene regulatory networks. © 2016. Published by The Company of Biologists Ltd.

  6. Early and late mammalian responses to heavy charged particles

    NASA Technical Reports Server (NTRS)

    Ainsworth, E. J.

    1986-01-01

    This overview summarizes murine results on acute lethality responses, inactivation of marrow CFU-S and intestinal microcolonies, testes weight loss, life span shortening, and posterior lens opacification in mice irradiated with heavy charged particles. RBE-LET relationships for these mammalian responses are compared with results from in vitro studies. The trend is that the maximum RBE for in vivo responses tends to be lower and occurs at a lower LET than for inactivation of V79 and T-1 cells in culture. Based on inactivation cross sections, the response of CFU-S in vivo conforms to expectations from earlier studies with prokaryotic systems and mammalian cells in culture. Effects of heavy ions are compared with fission spectrum neutrons, and the results are consistent with the interpretation that RBEs are lower than for fission neutrons at about the same LET, probably due to differences in track structure.

  7. Early Developmental and Evolutionary Origins of Gene Body DNA Methylation Patterns in Mammalian Placentas

    PubMed Central

    Schroeder, Diane I.; Jayashankar, Kartika; Douglas, Kory C.; Thirkill, Twanda L.; York, Daniel; Dickinson, Pete J.; Williams, Lawrence E.; Samollow, Paul B.; Ross, Pablo J.; Bannasch, Danika L.; Douglas, Gordon C.; LaSalle, Janine M.

    2015-01-01

    Over the last 20-80 million years the mammalian placenta has taken on a variety of morphologies through both divergent and convergent evolution. Recently we have shown that the human placenta genome has a unique epigenetic pattern of large partially methylated domains (PMDs) and highly methylated domains (HMDs) with gene body DNA methylation positively correlating with level of gene expression. In order to determine the evolutionary conservation of DNA methylation patterns and transcriptional regulatory programs in the placenta, we performed a genome-wide methylome (MethylC-seq) analysis of human, rhesus macaque, squirrel monkey, mouse, dog, horse, and cow placentas as well as opossum extraembryonic membrane. We found that, similar to human placenta, mammalian placentas and opossum extraembryonic membrane have globally lower levels of methylation compared to somatic tissues. Higher relative gene body methylation was the conserved feature across all mammalian placentas, despite differences in PMD/HMDs and absolute methylation levels. Specifically, higher methylation over the bodies of genes involved in mitosis, vesicle-mediated transport, protein phosphorylation, and chromatin modification was observed compared with the rest of the genome. As in human placenta, higher methylation is associated with higher gene expression and is predictive of genic location across species. Analysis of DNA methylation in oocytes and preimplantation embryos shows a conserved pattern of gene body methylation similar to the placenta. Intriguingly, mouse and cow oocytes and mouse early embryos have PMD/HMDs but their placentas do not, suggesting that PMD/HMDs are a feature of early preimplantation methylation patterns that become lost during placental development in some species and following implantation of the embryo. PMID:26241857

  8. Where hearing starts: the development of the mammalian cochlea.

    PubMed

    Basch, Martin L; Brown, Rogers M; Jen, Hsin-I; Groves, Andrew K

    2016-02-01

    The mammalian cochlea is a remarkable sensory organ, capable of perceiving sound over a range of 10(12) in pressure, and discriminating both infrasonic and ultrasonic frequencies in different species. The sensory hair cells of the mammalian cochlea are exquisitely sensitive, responding to atomic-level deflections at speeds on the order of tens of microseconds. The number and placement of hair cells are precisely determined during inner ear development, and a large number of developmental processes sculpt the shape, size and morphology of these cells along the length of the cochlear duct to make them optimally responsive to different sound frequencies. In this review, we briefly discuss the evolutionary origins of the mammalian cochlea, and then describe the successive developmental processes that lead to its induction, cell cycle exit, cellular patterning and the establishment of topologically distinct frequency responses along its length. © 2015 Anatomical Society.

  9. Genetic regulation of mammalian gonad development.

    PubMed

    Eggers, Stefanie; Ohnesorg, Thomas; Sinclair, Andrew

    2014-11-01

    Sex-specific gonadal development starts with formation of the bipotential gonad, which then differentiates into either a mature testis or an ovary. This process is dependent on activation of either the testis-specific or the ovary-specific pathway while the opposite pathway is continuously repressed. A network of transcription factors tightly regulates initiation and maintenance of these distinct pathways; disruption of these networks can lead to disorders of sex development in humans and male-to-female or female-to-male sex reversal in mice. Sry is the Y-linked master switch that is both required and sufficient to drive the testis-determining pathway. Another key component of the testis pathway is Sox9, which acts immediately downstream of Sry. In contrast to the testis pathway, no single sex-determining factor has been identified in the ovary pathway; however, multiple genes, such as Foxl2, Rspo1, Ctnnb1, and Wnt4, seem to work synergistically and in parallel to ensure proper ovary development. Our understanding of the regulatory networks that underpin testis and ovary development has grown substantially over the past two decades.

  10. Histone H3.3 maintains genome integrity during mammalian development

    PubMed Central

    Jang, Chuan-Wei; Shibata, Yoichiro; Starmer, Joshua; Yee, Della; Magnuson, Terry

    2015-01-01

    Histone H3.3 is a highly conserved histone H3 replacement variant in metazoans and has been implicated in many important biological processes, including cell differentiation and reprogramming. Germline and somatic mutations in H3.3 genomic incorporation pathway components or in H3.3 encoding genes have been associated with human congenital diseases and cancers, respectively. However, the role of H3.3 in mammalian development remains unclear. To address this question, we generated H3.3-null mouse models through classical genetic approaches. We found that H3.3 plays an essential role in mouse development. Complete depletion of H3.3 leads to developmental retardation and early embryonic lethality. At the cellular level, H3.3 loss triggers cell cycle suppression and cell death. Surprisingly, H3.3 depletion does not dramatically disrupt gene regulation in the developing embryo. Instead, H3.3 depletion causes dysfunction of heterochromatin structures at telomeres, centromeres, and pericentromeric regions of chromosomes, leading to mitotic defects. The resulting karyotypical abnormalities and DNA damage lead to p53 pathway activation. In summary, our results reveal that an important function of H3.3 is to support chromosomal heterochromatic structures, thus maintaining genome integrity during mammalian development. PMID:26159997

  11. Early Developments, 1998.

    ERIC Educational Resources Information Center

    Little, Loyd, Ed.

    1998-01-01

    This document consists of the two 1998 issues of a journal reporting new research in early child development conducted by the Frank Porter Graham Child Development Center at the University of North Carolina at Chapel Hill. In the Spring 1998 issue, articles highlight the Center's diverse cross-cultural projects and global research, training and…

  12. Faunal reorganisation in terrestrial mammalian communities: evidence from France during the Lateglacial-Early Holocene transition

    NASA Astrophysics Data System (ADS)

    Bridault, Anne

    2010-05-01

    The Lateglacial-Early Holocene transition is characterized by rapid oscillations between warm and cold episodes. Their impact on ecosystem dynamics was particularly pronounced in north-western Europe where hunter-gatherer societies experienced a succession of environmental transformations, including the expansion and dispersal of biotic communities and changing herbivore habitats. Recent archaeozoological studies and AMS direct dating on mammalian bones/or bone collagen allow to map and precise this process at a supra-regional scale (France). At regional scales (i.e. Paris Basin & Jura-Northern French Alps), results indicate a rapid faunal reorganisation at the end of Lateglacial that will be presented in detail. Composition of faunal assemblages remains then unchanged during the Early Holocene. By contrast, significant herbivore habitat changes are recorded during the Early Holocene by other proxies (pollen data and isotopic data) and a decrease in Red Deer size through time is evidenced by osteometrical analyses. Hypotheses regarding the kind of adaptation process experienced by the faunal communities through time will be presented. Factors that may have controlled the observed changes will be discussed.

  13. Development and evolution of the mammalian limb: adaptive diversification of nails, hooves, and claws.

    PubMed

    Hamrick, M W

    2001-01-01

    Paleontological evidence indicates that the evolutionary diversification of mammals early in the Cenozoic era was characterized by an adaptive radiation of distal limb structures. Likewise, neontological data show that morphological variation in distal limb integumentary appendages (e.g., nails, hooves, and claws) can be observed not only among distantly related mammalian taxa but also among closely related species within the same clade. Comparative analysis of nail, claw, and hoof morphogenesis reveals relatively subtle differences in mesenchymal and epithelial patterning underlying these adult differences in distal limb appendage morphology. Furthermore, studies of regulatory gene expression during vertebrate claw development demonstrate that many of the signaling molecules involved in patterning ectodermal derivatives such as teeth, hair, and feathers are also involved in organizing mammalian distal limb appendages. For example, Bmp4 signaling plays an important role during the recruitment of mesenchymal cells into the condensations forming the terminal phalanges, whereas Msx2 affects the length of nails and claws by suppressing proliferation of germinal epidermal cells. Evolutionary changes in the form of distal integumentary appendages may therefore result from changes in gene expression during formation of mesenchymal condensations (Bmp4, posterior Hox genes), induction of the claw fold and germinal matrix (shh), and/or proliferation of epidermal cells in the claw matrix (Msx1, Msx2). The prevalence of convergences and parallelisms in nail and claw structure among mammals underscores the existence of multiple morphogenetic pathways for evolutionary change in distal limb appendages.

  14. Early Childhood Development.

    ERIC Educational Resources Information Center

    Koh, Edgar, Ed.

    1989-01-01

    Focused on early childhood development, this "UNICEF Intercom" asserts that developmental programs should aim to give children a fair chance at growth beyond survival. First presented are moral, scientific, social equity, economic, population, and programatic arguments for looking beyond the fundamental objective of saving young lives.…

  15. Early Program Development

    NASA Image and Video Library

    1971-01-01

    This 1971 artist's concept shows a Nuclear Shuttle and an early Space Shuttle docked with an Orbital Propellant Depot. As envisioned by Marshall Space Flight Center Program Development persornel, an orbital modular propellant storage depot, supplied periodically by the Space Shuttle or Earth-to-orbit fuel tankers, would be critical in making available large amounts of fuel to various orbital vehicles and spacecraft.

  16. Early Program Development

    NASA Image and Video Library

    1970-01-01

    This artist's concept from 1970 shows a Nuclear Shuttle docked to an Orbital Propellant Depot and an early Space Shuttle. As envisioned by Marshall Space Flight Center Program Development plarners, the Nuclear Shuttle, in either manned or unmanned mode, would deliver payloads to lunar orbit or other destinations then return to Earth orbit for refueling and additonal missions.

  17. Mammalian brain development and our grandmothering life history.

    PubMed

    Hawkes, Kristen; Finlay, Barbara L

    2018-05-02

    Among mammals, including humans, adult brain size and the relative size of brain components depend precisely on the duration of a highly regular process of neural development. Much wider variation is seen in rates of body growth and the state of neural maturation at life history events like birth and weaning. Large brains result from slow maturation, which in humans is accompanied by weaning early with respect to both neural maturation and longevity. The grandmother hypothesis proposes this distinctive combination of life history features evolved as ancestral populations began to depend on foods that just weaned juveniles couldn't handle. Here we trace possible reciprocal connections between brain development and life history, highlighting the resulting extended neural plasticity in a wider cognitive ecology of allomaternal care that distinguishes human ontogeny with consequences for other peculiarities of our lineage. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Effects of Simulated Weightlessness on Mammalian Development. Part 2: Meiotic Maturation of Mouse Oocytes During Clinostat Rotation

    NASA Technical Reports Server (NTRS)

    Wolgemuth, D. J.; Grills, G. S.

    1985-01-01

    In order to understand the role of gravity in basic cellular processes that are important during development, the effects of a simulated microgravity environment on mammalian gametes and early embryos cultured in vitro are examined. A microgravity environment is simulated by use of a clinostat, which essentially reorients cells relative to the gravity vector. Initial studies have focused on assessing the effects of clinostat rotation on the meiotic progression of mouse oocytes. Modifications centered on providing the unique in vitro culture of the clinostat requirements of mammalian oocytes and embryos: 37 C temperature, constant humidity, and a 5% CO2 in air environment. The oocytes are observed under the dissecting microscope for polar body formation and gross morphological appearance. They are then processed for cytogenetic analysis.

  19. Unique genome organization of non-mammalian papillomaviruses provides insights into the evolution of viral early proteins.

    PubMed

    Van Doorslaer, Koenraad; Ruoppolo, Valeria; Schmidt, Annie; Lescroël, Amelie; Jongsomjit, Dennis; Elrod, Megan; Kraberger, Simona; Stainton, Daisy; Dugger, Katie M; Ballard, Grant; Ainley, David G; Varsani, Arvind

    2017-07-01

    The family Papillomaviridae contains more than 320 papillomavirus types, with most having been identified as infecting skin and mucosal epithelium in mammalian hosts. To date, only nine non-mammalian papillomaviruses have been described from birds ( n  = 5), a fish ( n  = 1), a snake ( n  = 1), and turtles ( n  = 2). The identification of papillomaviruses in sauropsids and a sparid fish suggests that early ancestors of papillomaviruses were already infecting the earliest Euteleostomi. The Euteleostomi clade includes more than 90 per cent of the living vertebrate species, and progeny virus could have been passed on to all members of this clade, inhabiting virtually every habitat on the planet. As part of this study, we isolated a novel papillomavirus from a 16-year-old female Adélie penguin ( Pygoscelis adeliae ) from Cape Crozier, Ross Island (Antarctica). The new papillomavirus shares ∼64 per cent genome-wide identity to a previously described Adélie penguin papillomavirus. Phylogenetic analyses show that the non-mammalian viruses (expect the python, Morelia spilota , associated papillomavirus) cluster near the base of the papillomavirus evolutionary tree. A papillomavirus isolated from an avian host (Northern fulmar; Fulmarus glacialis ), like the two turtle papillomaviruses, lacks a putative E9 protein that is found in all other avian papillomaviruses. Furthermore, the Northern fulmar papillomavirus has an E7 more similar to the mammalian viruses than the other avian papillomaviruses. Typical E6 proteins of mammalian papillomaviruses have two Zinc finger motifs, whereas the sauropsid papillomaviruses only have one such motif. Furthermore, this motif is absent in the fish papillomavirus. Thus, it is highly likely that the most recent common ancestor of the mammalian and sauropsid papillomaviruses had a single motif E6. It appears that a motif duplication resulted in mammalian papillomaviruses having a double Zinc finger motif in E6. We

  20. Unique genome organization of non-mammalian papillomaviruses provides insights into the evolution of viral early proteins

    USGS Publications Warehouse

    Van Doorslaer, Koenraad; Ruoppolo, Valeria; Schmidt, Annie; Lescroël, Amelie; Jongsomjit, Dennis; Elrod, Megan; Kraberger, Simona; Stainton, Daisy; Dugger, Katie M.; Ballard, Grant; Ainley, David G.; Varsani, Arvind

    2017-01-01

    The family Papillomaviridae contains more than 320 papillomavirus types, with most having been identified as infecting skin and mucosal epithelium in mammalian hosts. To date, only nine non-mammalian papillomaviruses have been described from birds (n = 5), a fish (n = 1), a snake (n = 1), and turtles (n = 2). The identification of papillomaviruses in sauropsids and a sparid fish suggests that early ancestors of papillomaviruses were already infecting the earliest Euteleostomi. The Euteleostomi clade includes more than 90 per cent of the living vertebrate species, and progeny virus could have been passed on to all members of this clade, inhabiting virtually every habitat on the planet. As part of this study, we isolated a novel papillomavirus from a 16-year-old female Adélie penguin (Pygoscelis adeliae) from Cape Crozier, Ross Island (Antarctica). The new papillomavirus shares ∼64 per cent genome-wide identity to a previously described Adélie penguin papillomavirus. Phylogenetic analyses show that the non-mammalian viruses (expect the python, Morelia spilota, associated papillomavirus) cluster near the base of the papillomavirus evolutionary tree. A papillomavirus isolated from an avian host (Northern fulmar; Fulmarus glacialis), like the two turtle papillomaviruses, lacks a putative E9 protein that is found in all other avian papillomaviruses. Furthermore, the Northern fulmar papillomavirus has an E7 more similar to the mammalian viruses than the other avian papillomaviruses. Typical E6 proteins of mammalian papillomaviruses have two Zinc finger motifs, whereas the sauropsid papillomaviruses only have one such motif. Furthermore, this motif is absent in the fish papillomavirus. Thus, it is highly likely that the most recent common ancestor of the mammalian and sauropsid papillomaviruses had a single motif E6. It appears that a motif duplication resulted in mammalian papillomaviruses having a double Zinc finger motif in E6. We estimated the

  1. Unique genome organization of non-mammalian papillomaviruses provides insights into the evolution of viral early proteins

    PubMed Central

    Ruoppolo, Valeria; Schmidt, Annie; Lescroël, Amelie; Jongsomjit, Dennis; Elrod, Megan; Kraberger, Simona; Stainton, Daisy; Dugger, Katie M; Ballard, Grant; Ainley, David G

    2017-01-01

    Abstract The family Papillomaviridae contains more than 320 papillomavirus types, with most having been identified as infecting skin and mucosal epithelium in mammalian hosts. To date, only nine non-mammalian papillomaviruses have been described from birds (n = 5), a fish (n = 1), a snake (n = 1), and turtles (n = 2). The identification of papillomaviruses in sauropsids and a sparid fish suggests that early ancestors of papillomaviruses were already infecting the earliest Euteleostomi. The Euteleostomi clade includes more than 90 per cent of the living vertebrate species, and progeny virus could have been passed on to all members of this clade, inhabiting virtually every habitat on the planet. As part of this study, we isolated a novel papillomavirus from a 16-year-old female Adélie penguin (Pygoscelis adeliae) from Cape Crozier, Ross Island (Antarctica). The new papillomavirus shares ∼64 per cent genome-wide identity to a previously described Adélie penguin papillomavirus. Phylogenetic analyses show that the non-mammalian viruses (expect the python, Morelia spilota, associated papillomavirus) cluster near the base of the papillomavirus evolutionary tree. A papillomavirus isolated from an avian host (Northern fulmar; Fulmarus glacialis), like the two turtle papillomaviruses, lacks a putative E9 protein that is found in all other avian papillomaviruses. Furthermore, the Northern fulmar papillomavirus has an E7 more similar to the mammalian viruses than the other avian papillomaviruses. Typical E6 proteins of mammalian papillomaviruses have two Zinc finger motifs, whereas the sauropsid papillomaviruses only have one such motif. Furthermore, this motif is absent in the fish papillomavirus. Thus, it is highly likely that the most recent common ancestor of the mammalian and sauropsid papillomaviruses had a single motif E6. It appears that a motif duplication resulted in mammalian papillomaviruses having a double Zinc finger motif in E6. We estimated

  2. Some process control/design considerations in the development of a microgravity mammalian cell bioreactor

    NASA Technical Reports Server (NTRS)

    Goochee, Charles F.

    1987-01-01

    The purpose is to review some of the physical/metabolic factors which must be considered in the development of an operating strategy for a mammalian cell bioreactor. Emphasis is placed on the dissolved oxygen and carbon dioxide requirements of growing mammalian epithelial cells. Literature reviews concerning oxygen and carbon dioxide requirements are discussed. A preliminary, dynamic model which encompasses the current features of the NASA bioreactor is presented. The implications of the literature survey and modeling effort on the design and operation of the NASA bioreactor are discussed.

  3. Regulation of germ cell development by intercellular signaling in the mammalian ovarian follicle.

    PubMed

    Clarke, Hugh J

    2018-01-01

    Prior to ovulation, the mammalian oocyte undergoes a process of differentiation within the ovarian follicle that confers on it the ability to give rise to an embryo. Differentiation comprises two phases-growth, during which the oocyte increases more than 100-fold in volume as it accumulates macromolecules and organelles that will sustain early embryogenesis; and meiotic maturation, during which the oocyte executes the first meiotic division and prepares for the second division. Entry of an oocyte into the growth phase appears to be triggered when the adjacent granulosa cells produce specific growth factors. As the oocyte grows, it elaborates a thick extracellular coat termed the zona pellucida. Nonetheless, cytoplasmic extensions of the adjacent granulosa cells, termed transzonal projections (TZPs), enable them to maintain contact-dependent communication with the oocyte. Through gap junctions located where the TZP tips meet the oocyte membrane, they provide the oocyte with products that sustain its metabolic activity and signals that regulate its differentiation. Conversely, the oocyte secretes diffusible growth factors that regulate proliferation and differentiation of the granulosa cells. Gap junction-permeable products of the granulosa cells prevent precocious initiation of meiotic maturation, and the gap junctions also enable oocyte maturation to begin in response to hormonal signals received by the granulosa cells. Development of the oocyte or the somatic compartment may also be regulated by extracellular vesicles newly identified in follicular fluid and at TZP tips, which could mediate intercellular transfer of macromolecules. Oocyte differentiation thus depends on continuous signaling interactions with the somatic cells of the follicle. WIREs Dev Biol 2018, 7:e294. doi: 10.1002/wdev.294 This article is categorized under: Gene Expression and Transcriptional Hierarchies > Cellular Differentiation Signaling Pathways > Cell Fate Signaling Early Embryonic

  4. Spaceflight Effects on Mammalian Development Summary of Research

    NASA Technical Reports Server (NTRS)

    Alberts, Jeffrey

    1998-01-01

    Pregnant rats were flown as small payloads on the Space Shuttle and studied during the flight and for approximately a week after returning to Earth, when they were due to deliver their offspring. Studies of vestibular function in the rat pups were examined as part of the research program. Daily videorecordings were made of the rats' behavior in the Animal Enclosure Modules (AEMS) and in identical compartments maintained in the Orbiter Environment Simulator at the Kennedy Space Center (referred to below as Synchronous Control groups). There was continuous postflight surveillance of the rat dams, including timelapse recordings of labor and delivery. The videorecords provided by crewmembers constitute the best systematic views of spaceflown rats to date, despite the dramatic deterioration of visibility sustained after about the 4th day of flight. We were able to make both qualitative and quantitative observations. Rats were observed to engage in a varied repertoire of species-typical activities within the confines of the AEM. We devised a kinematic coding scheme by which we classified and quantified the movements made by dams in space and in the 1-g control condition. We found that movements involving pitch and yaw were about equivalent in Flight and Synchronous animals. In contrast, Flight dams displayed about seven times more rolling movements than did Control. NASA enabled early access to the AEMs after the Shuttle landed. Rats were intact and healthy. Body weight gain during the 9-11 day flights was equivalent to Controls. Post-flight observations, derived from 24hr/day videorecordings, showed that Flight rats ambulated less, reared fewer times and spent less time bipedal than did controls. Overall, their anti-gravitational responses appeared compromised.

  5. Early Adolescent Ego Development.

    ERIC Educational Resources Information Center

    James, Michael A.

    1980-01-01

    Presented are the theoretical characteristics of social identity in early adolescence (ages 10 to 15). It is suggested that no longer is identity thought to begin with adolescence, but may have its beginnings in the preteen years. The article draws heavily on Eriksonian concepts. (Editor/KC)

  6. Early Program Development

    NASA Image and Video Library

    1969-01-01

    As part of the Space Task Group's recommendations for more commonality and integration in America's space program, Marshall Space Flight Center engineers proposed an orbiting propellant storage facility to augment Space Shuttle missions. In this artist's concept from 1969 an early version of the Space Shuttle is shown refueling at the facility.

  7. Mammalian follicular development and atresia: role of apoptosis.

    PubMed

    Asselin, E; Xiao, C W; Wang, Y F; Tsang, B K

    2000-01-01

    The regulation of follicular development and atresia is a complex process and involves interactions between endocrine factors (gonadotropins) and intraovarian regulators (sex steroids, growth factors and cytokines) in the control of follicular cell fate (i.e. proliferation, differentiation and programmed cell death). Granulosa and theca cells are key players in this fascinating process. As atresia is the fate of most follicles, understanding of how these physiological regulators participate in determining the destiny of the follicle (to degenerate or to ovulate) at cellular and subcellular levels is fundamental. This short review summarizes the role of intraovarian modulators of programmed cell death in the induction of atresia during follicular development. Copyright 2000 S. Karger AG, Basel

  8. Development and Tissue Origins of the Mammalian Cranial Base

    PubMed Central

    Iseki, S.; Bamforth, S. D.; Olsen, B. R.; Morriss-Kay, G. M.

    2008-01-01

    The vertebrate cranial base is a complex structure composed of bone, cartilage and other connective tissues underlying the brain; it is intimately connected with development of the face and cranial vault. Despite its central importance in craniofacial development, morphogenesis and tissue origins of the cranial base have not been studied in detail in the mouse, an important model organism. We describe here the location and time of appearance of the cartilages of the chondrocranium. We also examine the tissue origins of the mouse cranial base using a neural crest cell lineage cell marker, Wnt1-Cre/R26R, and a mesoderm lineage cell marker, Mesp1-Cre/R26R. The chondrocranium develops between E11 and E16 in the mouse, beginning with development of the caudal (occipital) chondrocranium, followed by chondrogenesis rostrally to form the nasal capsule, and finally fusion of these two parts via the midline central stem and the lateral struts of the vault cartilages. X-Gal staining of transgenic mice from E8.0 to 10 days post-natal showed that neural crest cells contribute to all of the cartilages that form the ethmoid, presphenoid, and basisphenoid bones with the exception of the hypochiasmatic cartilages. The basioccipital bone and non-squamous parts of the temporal bones are mesoderm derived. Therefore the prechordal head is mostly composed of neural crest-derived tissues, as predicted by the New Head Hypothesis. However, the anterior location of the mesoderm-derived hypochiasmatic cartilages, which are closely linked with the extra-ocular muscles, suggests that some tissues associated with the visual apparatus may have evolved independently of the rest of the “New Head”. PMID:18680740

  9. Early Program Development

    NASA Image and Video Library

    1969-01-01

    This 1969 artist's concept illustrates the use of three major elements of NASA's Integrated program, as proposed by President Nixon's Space Task Group. In Phases I and II, a Space Tug with a manipulator-equipped crew module removes a cargo module from an early Space Shuttle Orbiter and docks with it. In Phases III and IV, the Space Tug with attached cargo module flys toward a Nuclear Shuttle. As a result of the Space Task Group's recommendations for more commonality and integration in the American space program, Marshall Space Flight Center engineers studied many of the spacecraft depicted here.

  10. Retinoic acid signaling is dispensable for somatic development and function in the mammalian ovary.

    PubMed

    Minkina, Anna; Lindeman, Robin E; Gearhart, Micah D; Chassot, Anne-Amandine; Chaboissier, Marie-Christine; Ghyselinck, Norbert B; Bardwell, Vivian J; Zarkower, David

    2017-04-15

    Retinoic acid (RA) is a potent inducer of cell differentiation and plays an essential role in sex-specific germ cell development in the mammalian gonad. RA is essential for male gametogenesis and hence fertility. However, RA can also disrupt sexual cell fate in somatic cells of the testis, promoting transdifferentiation of male Sertoli cells to female granulosa-like cells when the male sexual regulator Dmrt1 is absent. The feminizing ability of RA in the Dmrt1 mutant somatic testis suggests that RA might normally play a role in somatic cell differentiation or cell fate maintenance in the ovary. To test for this possibility we disrupted RA signaling in somatic cells of the early fetal ovary using three genetic strategies and one pharmaceutical approach. We found that deleting all three RA receptors (RARs) in the XX somatic gonad at the time of sex determination did not significantly affect ovarian differentiation, follicle development, or female fertility. Transcriptome analysis of adult triple mutant ovaries revealed remarkably little effect on gene expression in the absence of somatic RAR function. Likewise, deletion of three RA synthesis enzymes (Aldh1a1-3) at the time of sex determination did not masculinize the ovary. A dominant-negative RAR transgene altered granulosa cell proliferation, likely due to interference with a non-RA signaling pathway, but did not prevent granulosa cell specification and oogenesis or abolish fertility. Finally, culture of fetal XX gonads with an RAR antagonist blocked germ cell meiotic initiation but did not disrupt sex-biased gene expression. We conclude that RA signaling, although crucial in the ovary for meiotic initiation, is not required for granulosa cell specification, differentiation, or reproductive function. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Mesozoic mammals from Arizona: new evidence on Mammalian evolution.

    PubMed

    Jenkins, F A; Crompton, A W; Downs, W R

    1983-12-16

    Knowledge of early mammalian evolution has been based on Old World Late Triassic-Early Jurassic faunas. The discovery of mammalian fossils of approximately equivalent age in the Kayenta Formation of northeastern Arizona gives evidence of greater diversity than known previously. A new taxon documents the development of an angular region of the jaw as a neomorphic process, and represents an intermediate stage in the origin of mammalian jaw musculature.

  12. Developing a de novo targeted knock-in method based on in utero electroporation into the mammalian brain.

    PubMed

    Tsunekawa, Yuji; Terhune, Raymond Kunikane; Fujita, Ikumi; Shitamukai, Atsunori; Suetsugu, Taeko; Matsuzaki, Fumio

    2016-09-01

    Genome-editing technology has revolutionized the field of biology. Here, we report a novel de novo gene-targeting method mediated by in utero electroporation into the developing mammalian brain. Electroporation of donor DNA with the CRISPR/Cas9 system vectors successfully leads to knock-in of the donor sequence, such as EGFP, to the target site via the homology-directed repair mechanism. We developed a targeting vector system optimized to prevent anomalous leaky expression of the donor gene from the plasmid, which otherwise often occurs depending on the donor sequence. The knock-in efficiency of the electroporated progenitors reached up to 40% in the early stage and 20% in the late stage of the developing mouse brain. Furthermore, we inserted different fluorescent markers into the target gene in each homologous chromosome, successfully distinguishing homozygous knock-in cells by color. We also applied this de novo gene targeting to the ferret model for the study of complex mammalian brains. Our results demonstrate that this technique is widely applicable for monitoring gene expression, visualizing protein localization, lineage analysis and gene knockout, all at the single-cell level, in developmental tissues. © 2016. Published by The Company of Biologists Ltd.

  13. Early Program Development

    NASA Image and Video Library

    1970-01-01

    In 1970, NASA initiated Phase A contracts to study alternate Space Shuttle designs in addition to the two-stage fully-reusable Space Shuttle system already under development. A number of alternate systems were developed to ensure the development of the optimum earth-to-orbit system, including the Stage-and-a-half Chemical Interorbital Shuttle, shown here. The concept would utilize a reusable marned spacecraft with an onboard propulsion system attached to an expendable fuel tank to provide supplementary propellants.

  14. Development in Early Childhood.

    ERIC Educational Resources Information Center

    Elkind, David

    1991-01-01

    Reviews some of the major cognitive, social, and emotional achievements of young children and discusses some of their limitations. Divides description of development into intellectual, language, social, and emotional development. Notes that this division represents adult categories of thought and does not represent young children's actual modes of…

  15. Behavioral biology of mammalian reproduction and development for a space station

    NASA Technical Reports Server (NTRS)

    Alberts, J. R.

    1983-01-01

    Space Station research includes two kinds of adaption to space: somatic (the adjustments made by an organism, within its lifetime, in response to local conditions), and transgenerational adaption (continuous exposure across sequential life cycles of genetic descendents). Transgenerational effects are akin to evolutionary process. Areas of a life Sciences Program in a space station address the questions of the behavioral biology of mammalian reproduction and development, using the Norway rat as the focus of experimentation.

  16. The parental non-equivalence of imprinting control regions during mammalian development and evolution.

    PubMed

    Schulz, Reiner; Proudhon, Charlotte; Bestor, Timothy H; Woodfine, Kathryn; Lin, Chyuan-Sheng; Lin, Shau-Ping; Prissette, Marine; Oakey, Rebecca J; Bourc'his, Déborah

    2010-11-18

    In mammals, imprinted gene expression results from the sex-specific methylation of imprinted control regions (ICRs) in the parental germlines. Imprinting is linked to therian reproduction, that is, the placenta and imprinting emerged at roughly the same time and potentially co-evolved. We assessed the transcriptome-wide and ontology effect of maternally versus paternally methylated ICRs at the developmental stage of setting of the chorioallantoic placenta in the mouse (8.5dpc), using two models of imprinting deficiency including completely imprint-free embryos. Paternal and maternal imprints have a similar quantitative impact on the embryonic transcriptome. However, transcriptional effects of maternal ICRs are qualitatively focused on the fetal-maternal interface, while paternal ICRs weakly affect non-convergent biological processes, with little consequence for viability at 8.5dpc. Moreover, genes regulated by maternal ICRs indirectly influence genes regulated by paternal ICRs, while the reverse is not observed. The functional dominance of maternal imprints over early embryonic development is potentially linked to selection pressures favoring methylation-dependent control of maternal over paternal ICRs. We previously hypothesized that the different methylation histories of ICRs in the maternal versus the paternal germlines may have put paternal ICRs under higher mutational pressure to lose CpGs by deamination. Using comparative genomics of 17 extant mammalian species, we show here that, while ICRs in general have been constrained to maintain more CpGs than non-imprinted sequences, the rate of CpG loss at paternal ICRs has indeed been higher than at maternal ICRs during evolution. In fact, maternal ICRs, which have the characteristics of CpG-rich promoters, have gained CpGs compared to non-imprinted CpG-rich promoters. Thus, the numerical and, during early embryonic development, functional dominance of maternal ICRs can be explained as the consequence of two

  17. The Parental Non-Equivalence of Imprinting Control Regions during Mammalian Development and Evolution

    PubMed Central

    Bestor, Timothy H.; Woodfine, Kathryn; Lin, Chyuan-Sheng; Lin, Shau-Ping; Prissette, Marine; Oakey, Rebecca J.; Bourc'his, Déborah

    2010-01-01

    In mammals, imprinted gene expression results from the sex-specific methylation of imprinted control regions (ICRs) in the parental germlines. Imprinting is linked to therian reproduction, that is, the placenta and imprinting emerged at roughly the same time and potentially co-evolved. We assessed the transcriptome-wide and ontology effect of maternally versus paternally methylated ICRs at the developmental stage of setting of the chorioallantoic placenta in the mouse (8.5dpc), using two models of imprinting deficiency including completely imprint-free embryos. Paternal and maternal imprints have a similar quantitative impact on the embryonic transcriptome. However, transcriptional effects of maternal ICRs are qualitatively focused on the fetal-maternal interface, while paternal ICRs weakly affect non-convergent biological processes, with little consequence for viability at 8.5dpc. Moreover, genes regulated by maternal ICRs indirectly influence genes regulated by paternal ICRs, while the reverse is not observed. The functional dominance of maternal imprints over early embryonic development is potentially linked to selection pressures favoring methylation-dependent control of maternal over paternal ICRs. We previously hypothesized that the different methylation histories of ICRs in the maternal versus the paternal germlines may have put paternal ICRs under higher mutational pressure to lose CpGs by deamination. Using comparative genomics of 17 extant mammalian species, we show here that, while ICRs in general have been constrained to maintain more CpGs than non-imprinted sequences, the rate of CpG loss at paternal ICRs has indeed been higher than at maternal ICRs during evolution. In fact, maternal ICRs, which have the characteristics of CpG-rich promoters, have gained CpGs compared to non-imprinted CpG-rich promoters. Thus, the numerical and, during early embryonic development, functional dominance of maternal ICRs can be explained as the consequence of two

  18. DEVELOPMENT, STANDARDIZATION AND VALIDATION OF THE MAMMALIAN IN VIVO ASSAYS IN THE PROPOSED TIER I SCREENING BATTERY FOR ENDOCRINE DISRUPTORS

    EPA Science Inventory

    This research directly supports the development, standardization and validation of several Tier 1 screening mammalian in vivo assays. Through the development and use of many of these assays for testing specific hypothesis in their respective research programs, these investigato...

  19. Early Program Development

    NASA Image and Video Library

    1970-01-01

    This artist's concept from 1970 shows a Nuclear Shuttle taking on fuel from an orbiting Liquid Hydrogen Depot. As envisioned by Marshall Space Flight Center Program Development persornel, the Nuclear Shuttle would deliver payloads to lunar orbit or other destinations then return to Earth orbit for refueling and additional missions.

  20. Early Program Development

    NASA Image and Video Library

    1970-01-01

    This 1970 artist's concept shows a Nuclear Shuttle in flight. As envisioned by Marshall Space Flight Center Program Development engineers, the Nuclear Shuttle would deliver payloads to lunar orbit or other destinations then return to Earth orbit for refueling and additional missions.

  1. Early Program Development

    NASA Image and Video Library

    1971-01-01

    In this 1971 artist's concept, the Nuclear Shuttle is shown in various space-based applications. As envisioned by Marshall Space Flight Center Program Development persornel, the Nuclear Shuttle would deliver payloads to geosychronous Earth orbits or lunar orbits then return to low Earth orbit for refueling. A cluster of Nuclear Shuttle units could form the basis for planetary missions.

  2. Early Program Development

    NASA Image and Video Library

    1971-01-01

    This 1971 artist's concept shows the Nuclear Shuttle in both its lunar logistics configuraton and geosynchronous station configuration. As envisioned by Marshall Space Flight Center Program Development persornel, the Nuclear Shuttle would deliver payloads to lunar orbits or other destinations then return to Earth orbit for refueling and additional missions.

  3. Early Program Development

    NASA Image and Video Library

    1963-01-01

    This artist's concept from 1963 shows a proposed NERVA (Nuclear Engine for Rocket Vehicle Application) incorporating the NRX-A1, the first NERVA-type cold flow reactor. The NERVA engine, based on Kiwi nuclear reactor technology, was intended to power a RIFT (Reactor-In-Flight-Test) nuclear stage, for which Marshall Space Flight Center had development responsibility.

  4. Nucleolus Precursor Bodies and Ribosome Biogenesis in Early Mammalian Embryos: Old Theories and New Discoveries.

    PubMed

    Fulka, Helena; Aoki, Fugaku

    2016-06-01

    In mammals, mature oocytes and early preimplantation embryos contain transcriptionally inactive structures termed nucleolus precursor bodies instead of the typical fibrillo-granular nucleoli. These nuclear organelles are essential and strictly of maternal origin. If they are removed from oocytes, the resulting embryos are unable to replace them and consequently fail to develop. Historically, nucleolus precursor bodies have been perceived as a passive repository site of nucleolar proteins that are required for embryos to form fully functional nucleoli. Recent results, however, contradict this long-standing dogma and show that these organelles are dispensable for nucleologenesis and ribosome biogenesis. In this article, we discuss the possible roles of nucleolus precursor bodies and propose how they might be involved in embryogenesis. Furthermore, we argue that these organelles are essential only shortly after fertilization and suggest that they might actively participate in centromeric chromatin establishment. © 2016 by the Society for the Study of Reproduction, Inc.

  5. Early Program Development

    NASA Image and Video Library

    2004-04-15

    This artist's concept illustrates the NERVA (Nuclear Engine for Rocket Vehicle Application) engine's hot bleed cycle in which a small amount of hydrogen gas is diverted from the thrust nozzle, thus eliminating the need for a separate system to drive the turbine. The NERVA engine, based on KIWI nuclear reactor technology, would power a RIFT (Reactor-In-Flight-Test) nuclear stage, for which the Marshall Space Flight Center had development responsibility.

  6. Early Program Development

    NASA Image and Video Library

    1970-01-01

    In this 1970 artist's concept, the Nuclear Shuttle is shown in its lunar and geosynchronous orbit configuration and in its planetary mission configuration. As envisioned by Marshall Space Flight Center Program Development plarners, the Nuclear Shuttle would deliver payloads to lunar orbit or other destinations then return to Earth orbit for refueling. A cluster of Nuclear Shuttle units could form the basis for planetary missions.

  7. Advances in the cryopreservation of mammalian oocytes and embryos: Development of ultrarapid vitrification

    PubMed Central

    2002-01-01

    The cryopreservation of embryos has become a powerful tool in assisted reproduction in several mammalian species. Embryos are cryopreserved by slow freezing or by vitrification. However, consistently high survival has not been obtained in most oocytes and in some embryos. The main reasons for the low survival would be sensitivity to low temperatures, which leads to chilling injury, and low permeability of the cell membrane, which leads to the formation of intracellular ice. As a strategy aiming to overcome these injuries, modified vitrification methods have been devised in which the cooling and warming rate is markedly increased by minimizing the volume of the solution and the container. The modified methods use electron microscope grids, open‐pulled straws, cryoloops, or container‐less microdrops. In this article, recent developments in the ultrarapid vitrification of mammalian oocytes and embryos are reviewed based on the understanding of the mechanisms of cell injury in cryopreservation. (Reprod Med Biol 2002; 1: 1–9) PMID:29699066

  8. Early Program Development

    NASA Image and Video Library

    1996-06-20

    Engineers at one of MSFC's vacuum chambers begin testing a microthruster model. The purpose of these tests are to collect sufficient data that will enabe NASA to develop microthrusters that will move the Space Shuttle, a future space station, or any other space related vehicle with the least amount of expended energy. When something is sent into outer space, the forces that try to pull it back to Earth (gravity) are very small so that it only requires a very small force to move very large objects. In space, a force equal to a paperclip can move an object as large as a car. Microthrusters are used to produce these small forces.

  9. Biomechanics of Early Cardiac Development

    PubMed Central

    Goenezen, Sevan; Rennie, Monique Y.

    2012-01-01

    Biomechanics affect early cardiac development, from looping to the development of chambers and valves. Hemodynamic forces are essential for proper cardiac development, and their disruption leads to congenital heart defects. A wealth of information already exists on early cardiac adaptations to hemodynamic loading, and new technologies, including high resolution imaging modalities and computational modeling, are enabling a more thorough understanding of relationships between hemodynamics and cardiac development. Imaging and modeling approaches, used in combination with biological data on cell behavior and adaptation, are paving the road for new discoveries on links between biomechanics and biology and their effect on cardiac development and fetal programming. PMID:22760547

  10. Replication labeling patterns and chromosome territories typical of mammalian nuclei are conserved in the early metazoan Hydra.

    PubMed

    Alexandrova, Olga; Solovei, Irina; Cremer, Thomas; David, Charles N

    2003-12-01

    To investigate the evolutionary conservation of higher order nuclear architecture previously described for mammalian cells we have analyzed the nuclear architecture of the simple polyp Hydra. These diploblastic organisms have large nuclei (8-10 microm) containing about 3x10(9) bp of DNA organized in 15 chromosome pairs. They belong to the earliest metazoan phylum and are separated from mammals by at least 600 million years. Single and double pulse labeling with halogenated nucleotides (bromodeoxyuridine, iododeoxyuridine and chlorodeoxyuridine) revealed striking similarities to the known sequence of replication labeling patterns in mammalian nuclei. These patterns reflect a persistent nuclear arrangement of early, mid-, and late replicating chromatin foci that could be identified during all stages of interphase over at least 5-10 cell generations. Segregation of labeled chromatids led after several cell divisions to nuclei with single or a few labeled chromosome territories. In such nuclei distinct clusters of labeled chromatin foci were separated by extended nuclear areas with non-labeled chromatin, which is typical of a territorial arrangement of interphase chromosomes. Our results indicate the conservation of fundamental features of higher order chromatin arrangements throughout the evolution of metazoan animals and suggest the existence of conserved mechanism(s) controlling this architecture.

  11. Sry and SoxE genes: How they participate in mammalian sex determination and gonadal development?

    PubMed

    She, Zhen-Yu; Yang, Wan-Xi

    2017-03-01

    In mammals, sex determination defines the differentiation of the bipotential genital ridge into either testes or ovaries. Sry, the mammalian Y-chromosomal testis-determining gene, is a master regulator of male sex determination. It acts to switch the undifferentiated genital ridge towards testis development, triggering the adoption of a male fate. Sry initiates a cascade of gene networks through the direct regulation of Sox9 expression and promotes supporting cell differentiation, Leydig cell specification, vasculature formation and testis cord development. In the absence of Sry, alternative genetic cascades, including female sex-determining genes RSPO1, Wnt4/β-catenin and Foxl2, are involved in the formation of female genitalia and the maintenance of female ovarian development. The mutual antagonisms between male and female sex-determining pathways are crucial in not just the initiation but also the maintenance of the somatic sex of the gonad throughout the organism's lifetime. Any imbalances in above sex-determining genes can cause disorders of sex development in humans and mice. In this review, we provide a detailed summary of the expression profiles, biochemical properties and developmental functions of Sry and SoxE genes in embryonic testis development and adult gonadal development. We also briefly summarize the dedicate balances between male and female sex-determining genes in mammalian sex development, with particular highlights on the molecular actions of Sry and Sox9 transcription factors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Creb1 regulates late stage mammalian lung development via respiratory epithelial and mesenchymal-independent mechanisms

    PubMed Central

    Antony, N.; McDougall, A. R.; Mantamadiotis, T.; Cole, T. J.; Bird, A. D.

    2016-01-01

    During mammalian lung development, the morphological transition from respiratory tree branching morphogenesis to a predominantly saccular architecture, capable of air-breathing at birth, is dependent on physical forces as well as molecular signaling by a range of transcription factors including the cAMP response element binding protein 1 (Creb1). Creb1−/− mutant mice exhibit complete neonatal lethality consistent with a lack of lung maturation beyond the branching phase. To further define its role in the developing mouse lung, we deleted Creb1 separately in the respiratory epithelium and mesenchyme. Surprisingly, we found no evidence of a morphological lung defect nor compromised neonatal survival in either conditional Creb1 mutant. Interestingly however, loss of mesenchymal Creb1 on a genetic background lacking the related Crem protein showed normal lung development but poor neonatal survival. To investigate the underlying requirement for Creb1 for normal lung development, Creb1−/− mice were re-examined for defects in both respiratory muscles and glucocorticoid hormone signaling, which are also required for late stage lung maturation. However, these systems appeared normal in Creb1−/− mice. Together our results suggest that the requirement of Creb1 for normal mammalian lung morphogenesis is not dependent upon its expression in lung epithelium or mesenchyme, nor its role in musculoskeletal development. PMID:27150575

  13. Krüppel-like factors in mammalian stem cells and development

    PubMed Central

    Bialkowska, Agnieszka B.; Yang, Vincent W.

    2017-01-01

    Krüppel-like factors (KLFs) are a family of zinc-finger transcription factors that are found in many species. Recent studies have shown that KLFs play a fundamental role in regulating diverse biological processes such as cell proliferation, differentiation, development and regeneration. Of note, several KLFs are also crucial for maintaining pluripotency and, hence, have been linked to reprogramming and regenerative medicine approaches. Here, we review the crucial functions of KLFs in mammalian embryogenesis, stem cell biology and regeneration, as revealed by studies of animal models. We also highlight how KLFs have been implicated in human diseases and outline potential avenues for future research. PMID:28246209

  14. A gene network model accounting for development and evolution of mammalian teeth

    PubMed Central

    Salazar-Ciudad, Isaac; Jernvall, Jukka

    2002-01-01

    Generation of morphological diversity remains a challenge for evolutionary biologists because it is unclear how an ultimately finite number of genes involved in initial pattern formation integrates with morphogenesis. Ideally, models used to search for the simplest developmental principles on how genes produce form should account for both developmental process and evolutionary change. Here we present a model reproducing the morphology of mammalian teeth by integrating experimental data on gene interactions and growth into a morphodynamic mechanism in which developing morphology has a causal role in patterning. The model predicts the course of tooth-shape development in different mammalian species and also reproduces key transitions in evolution. Furthermore, we reproduce the known expression patterns of several genes involved in tooth development and their dynamics over developmental time. Large morphological effects frequently can be achieved by small changes, according to this model, and similar morphologies can be produced by different changes. This finding may be consistent with why predicting the morphological outcomes of molecular experiments is challenging. Nevertheless, models incorporating morphology and gene activity show promise for linking genotypes to phenotypes. PMID:12048258

  15. Role of H1 Linker Histones in Mammalian Development and Stem Cell Differentiation

    PubMed Central

    Pan, Chenyi; Fan, Yuhong

    2016-01-01

    H1 linker histones are key chromatin architectural proteins facilitating the formation of higher order chromatin structures. The H1 family constitutes the most heterogeneous group of histone proteins, with eleven non-allelic H1 variants in mammals. H1 variants differ in their biochemical properties and exhibit significant sequence divergence from one another, yet most of them are highly conserved during evolution from mouse to human. H1 variants are differentially regulated during development and their cellular compositions undergo dramatic changes in embryogenesis, gametogenesis, tissue maturation and cellular differentiation. As a group, H1 histones are essential for mouse development and proper stem cell differentiation. Here we summarize our current knowledge on the expression and functions of H1 variants in mammalian development and stem cell differentiation. Their diversity, sequence conservation, complex expression and distinct functions suggest that H1s mediate chromatin reprogramming and contribute to the large variations and complexity of chromatin structure and gene expression in the mammalian genome. PMID:26689747

  16. Early androgen exposure and human gender development.

    PubMed

    Hines, Melissa; Constantinescu, Mihaela; Spencer, Debra

    2015-01-01

    During early development, testosterone plays an important role in sexual differentiation of the mammalian brain and has enduring influences on behavior. Testosterone exerts these influences at times when the testes are active, as evidenced by higher concentrations of testosterone in developing male than in developing female animals. This article critically reviews the available evidence regarding influences of testosterone on human gender-related development. In humans, testosterone is elevated in males from about weeks 8 to 24 of gestation and then again during early postnatal development. Individuals exposed to atypical concentrations of testosterone or other androgenic hormones prenatally, for example, because of genetic conditions or because their mothers were prescribed hormones during pregnancy, have been consistently found to show increased male-typical juvenile play behavior, alterations in sexual orientation and gender identity (the sense of self as male or female), and increased tendencies to engage in physically aggressive behavior. Studies of other behavioral outcomes following dramatic androgen abnormality prenatally are either too small in their numbers or too inconsistent in their results, to provide similarly conclusive evidence. Studies relating normal variability in testosterone prenatally to subsequent gender-related behavior have produced largely inconsistent results or have yet to be independently replicated. For studies of prenatal exposures in typically developing individuals, testosterone has been measured in single samples of maternal blood or amniotic fluid. These techniques may not be sufficiently powerful to consistently detect influences of testosterone on behavior, particularly in the relatively small samples that have generally been studied. The postnatal surge in testosterone in male infants, sometimes called mini-puberty, may provide a more accessible opportunity for measuring early androgen exposure during typical development. This

  17. Transgenic mice: an irreplaceable tool for the study of mammalian development and biology.

    PubMed

    Babinet, C

    2000-11-01

    Stable integration into the mouse genome of exogenous genetic information, i.e., the creation of transgenic mice, has become a privileged way of analyzing gene function in normal development and pathology. Both gene addition and gene replacement may be performed. This has allowed, in particular, the creation of mice in which precise mutations are introduced into a given gene. Furthermore, in recent years, strategies that induce the expression of a mutation in a given type of cell and/or at a given time in development have been developed. Thus, the transgenic methodology affords a unique and irreplaceable tool for the study of mammalian development and biology and for the creation of animal models for human genetic diseases.

  18. Dynamic transcriptional symmetry-breaking in pre-implantation mammalian embryo development revealed by single-cell RNA-seq.

    PubMed

    Shi, Junchao; Chen, Qi; Li, Xin; Zheng, Xiudeng; Zhang, Ying; Qiao, Jie; Tang, Fuchou; Tao, Yi; Zhou, Qi; Duan, Enkui

    2015-10-15

    During mammalian pre-implantation embryo development, when the first asymmetry emerges and how it develops to direct distinct cell fates remain longstanding questions. Here, by analyzing single-blastomere transcriptome data from mouse and human pre-implantation embryos, we revealed that the initial blastomere-to-blastomere biases emerge as early as the first embryonic cleavage division, following a binomial distribution pattern. The subsequent zygotic transcriptional activation further elevated overall blastomere-to-blastomere biases during the two- to 16-cell embryo stages. The trends of transcriptional asymmetry fell into two distinct patterns: for some genes, the extent of asymmetry was minimized between blastomeres (monostable pattern), whereas other genes, including those known to be lineage specifiers, showed ever-increasing asymmetry between blastomeres (bistable pattern), supposedly controlled by negative or positive feedbacks. Moreover, our analysis supports a scenario in which opposing lineage specifiers within an early blastomere constantly compete with each other based on their relative ratio, forming an inclined 'lineage strength' that pushes the blastomere onto a predisposed, yet flexible, lineage track before morphological distinction. © 2015. Published by The Company of Biologists Ltd.

  19. The cell cycle of early mammalian embryos: lessons from genetic mouse models.

    PubMed

    Artus, Jérôme; Babinet, Charles; Cohen-Tannoudji, Michel

    2006-03-01

    Genes coding for cell cycle components predicted to be essential for its regulation have been shown to be dispensable in mice, at the whole organism level. Such studies have highlighted the extraordinary plasticity of the embryonic cell cycle and suggest that many aspects of in vivo cell cycle regulation remain to be discovered. Here, we discuss the particularities of the mouse early embryonic cell cycle and review the mutations that result in cell cycle defects during mouse early embryogenesis, including deficiencies for genes of the cyclin family (cyclin A2 and B1), genes involved in cell cycle checkpoints (Mad2, Bub3, Chk1, Atr), genes involved in ubiquitin and ubiquitin-like pathways (Uba3, Ubc9, Cul1, Cul3, Apc2, Apc10, Csn2) as well as genes the function of which had not been previously ascribed to cell cycle regulation (Cdc2P1, E4F and Omcg1).

  20. Development of an Improved Mammalian Overexpression Method for Human CD62L

    PubMed Central

    Brown, Haley A.; Roth, Gwynne; Holzapfel, Genevieve; Shen, Sarek; Rahbari, Kate; Ireland, Joanna; Zou, Zhongcheng; Sun, Peter D.

    2014-01-01

    We have previously developed a glutamine synthetase (GS)-based mammalian recombinant protein expression system that is capable of producing 5 to 30 mg/L recombinant proteins. The over expression is based on multiple rounds of target gene amplification driven by methionine sulfoximine (MSX), an inhibitor of glutamine synthetase. However, like other stable mammalian over expression systems, a major shortcoming of the GS-based expression system is its lengthy turn-around time, typically taking 4–6 months to produce. To shorten the construction time, we replaced the muti-round target gene amplifications with single-round in situ amplifications, thereby shortening the cell line construction to 2 months. The single-round in situ amplification method resulted in highest recombinant CD62L expressing CHO cell lines producing ~5mg/L soluble CD62L, similar to those derived from the multi-round amplification and selection method. In addition, we developed a MSX resistance assay as an alternative to utilizing ELISA for evaluating the expression level of stable recombinant CHO cell lines. PMID:25286402

  1. Telomere lengthening early in development.

    PubMed

    Liu, Lin; Bailey, Susan M; Okuka, Maja; Muñoz, Purificación; Li, Chao; Zhou, Lingjun; Wu, Chao; Czerwiec, Eva; Sandler, Laurel; Seyfang, Andreas; Blasco, Maria A; Keefe, David L

    2007-12-01

    Stem cells and cancer cells maintain telomere length mostly through telomerase. Telomerase activity is high in male germ line and stem cells, but is low or absent in mature oocytes and cleavage stage embryos, and then high again in blastocysts. How early embryos reset telomere length remains poorly understood. Here, we show that oocytes actually have shorter telomeres than somatic cells, but their telomeres lengthen remarkably during early cleavage development. Moreover, parthenogenetically activated oocytes also lengthen their telomeres, thus the capacity to elongate telomeres must reside within oocytes themselves. Notably, telomeres also elongate in the early cleavage embryos of telomerase-null mice, demonstrating that telomerase is unlikely to be responsible for the abrupt lengthening of telomeres in these cells. Coincident with telomere lengthening, extensive telomere sister-chromatid exchange (T-SCE) and colocalization of the DNA recombination proteins Rad50 and TRF1 were observed in early cleavage embryos. Both T-SCE and DNA recombination proteins decrease in blastocyst stage embryos, whereas telomerase activity increases and telomeres elongate only slowly. We suggest that telomeres lengthen during the early cleavage cycles following fertilization through a recombination-based mechanism, and that from the blastocyst stage onwards, telomerase only maintains the telomere length established by this alternative mechanism.

  2. A Mammalian Conserved Element Derived from SINE Displays Enhancer Properties Recapitulating Satb2 Expression in Early-Born Callosal Projection Neurons

    PubMed Central

    Nakanishi, Akiko; Sasaki, Takeshi; Yan, Kuo; Tarabykin, Victor; Vigier, Lisa; Sumiyama, Kenta; Hirakawa, Mika; Nishihara, Hidenori; Pierani, Alessandra; Okada, Norihiro

    2011-01-01

    Short interspersed repetitive elements (SINEs) are highly repeated sequences that account for a significant proportion of many eukaryotic genomes and are usually considered “junk DNA”. However, we previously discovered that many AmnSINE1 loci are evolutionarily conserved across mammalian genomes, suggesting that they may have acquired significant functions involved in controlling mammalian-specific traits. Notably, we identified the AS021 SINE locus, located 390 kbp upstream of Satb2. Using transgenic mice, we showed that this SINE displays specific enhancer activity in the developing cerebral cortex. The transcription factor Satb2 is expressed by cortical neurons extending axons through the corpus callosum and is a determinant of callosal versus subcortical projection. Mouse mutants reveal a crucial function for Sabt2 in corpus callosum formation. In this study, we compared the enhancer activity of the AS021 locus with Satb2 expression during telencephalic development in the mouse. First, we showed that the AS021 enhancer is specifically activated in early-born Satb2+ neurons. Second, we demonstrated that the activity of the AS021 enhancer recapitulates the expression of Satb2 at later embryonic and postnatal stages in deep-layer but not superficial-layer neurons, suggesting the possibility that the expression of Satb2 in these two subpopulations of cortical neurons is under genetically distinct transcriptional control. Third, we showed that the AS021 enhancer is activated in neurons projecting through the corpus callosum, as described for Satb2+ neurons. Notably, AS021 drives specific expression in axons crossing through the ventral (TAG1−/NPY+) portion of the corpus callosum, confirming that it is active in a subpopulation of callosal neurons. These data suggest that exaptation of the AS021 SINE locus might be involved in enhancement of Satb2 expression, leading to the establishment of interhemispheric communication via the corpus callosum, a eutherian

  3. Early Eocene fossils suggest that the mammalian order Perissodactyla originated in India.

    PubMed

    Rose, Kenneth D; Holbrook, Luke T; Rana, Rajendra S; Kumar, Kishor; Jones, Katrina E; Ahrens, Heather E; Missiaen, Pieter; Sahni, Ashok; Smith, Thierry

    2014-11-20

    Cambaytheres (Cambaytherium, Nakusia and Kalitherium) are recently discovered early Eocene placental mammals from the Indo-Pakistan region. They have been assigned to either Perissodactyla (the clade including horses, tapirs and rhinos, which is a member of the superorder Laurasiatheria) or Anthracobunidae, an obscure family that has been variously considered artiodactyls or perissodactyls, but most recently placed at the base of Proboscidea or of Tethytheria (Proboscidea+Sirenia, superorder Afrotheria). Here we report new dental, cranial and postcranial fossils of Cambaytherium, from the Cambay Shale Formation, Gujarat, India (~54.5 Myr). These fossils demonstrate that cambaytheres occupy a pivotal position as the sister taxon of Perissodactyla, thereby providing insight on the phylogenetic and biogeographic origin of Perissodactyla. The presence of the sister group of perissodactyls in western India near or before the time of collision suggests that Perissodactyla may have originated on the Indian Plate during its final drift toward Asia.

  4. Mechanical activation of mammalian target of rapamycin pathway is required for cartilage development

    PubMed Central

    Guan, Yingjie; Yang, Xu; Yang, Wentian; Charbonneau, Cherie; Chen, Qian

    2014-01-01

    Mechanical stress regulates development by modulating cell signaling and gene expression. However, the cytoplasmic components mediating mechanotransduction remain unclear. In this study, elimination of muscle contraction during chicken embryonic development resulted in a reduction in the activity of mammalian target of rapamycin (mTOR) in the cartilaginous growth plate. Inhibition of mTOR activity led to significant inhibition of chondrocyte proliferation, cartilage tissue growth, and expression of chondrogenic genes, including Indian hedgehog (Ihh), a critical mediator of mechanotransduction. Conversely, cyclic loading (1 Hz, 5% matrix deformation) of embryonic chicken growth plate chondrocytes in 3-dimensional (3D) collagen scaffolding induced sustained activation of mTOR. Mechanical activation of mTOR occurred in serum-free medium, indicating that it is independent of growth factor or nutrients. Treatment of chondrocytes with Rapa abolished mechanical activation of cell proliferation and Ihh gene expression. Cyclic loading of chondroprogenitor cells deficient in SH2-containing protein tyrosine phosphatase 2 (Shp2) further enhanced mechanical activation of mTOR, cell proliferation, and chondrogenic gene expression. This result suggests that Shp2 is an antagonist of mechanotransduction through inhibition of mTOR activity. Our data demonstrate that mechanical activation of mTOR is necessary for cell proliferation, chondrogenesis, and cartilage growth during bone development, and that mTOR is an essential mechanotransduction component modulated by Shp2 in the cytoplasm.—Guan, Y., Yang, X., Yang, W., Charbonneau, C., Chen, Q. Mechanical activation of mammalian target of rapamycin pathway is required for cartilage development. PMID:25002119

  5. The interaction between early life epilepsy and autistic-like behavioral consequences: a role for the mammalian target of rapamycin (mTOR) pathway.

    PubMed

    Talos, Delia M; Sun, Hongyu; Zhou, Xiangping; Fitzgerald, Erin C; Jackson, Michele C; Klein, Peter M; Lan, Victor J; Joseph, Annelise; Jensen, Frances E

    2012-01-01

    Early life seizures can result in chronic epilepsy, cognitive deficits and behavioral changes such as autism, and conversely epilepsy is common in autistic children. We hypothesized that during early brain development, seizures could alter regulators of synaptic development and underlie the interaction between epilepsy and autism. The mammalian Target of Rapamycin (mTOR) modulates protein translation and is dysregulated in Tuberous Sclerosis Complex, a disorder characterized by epilepsy and autism. We used a rodent model of acute hypoxia-induced neonatal seizures that results in long term increases in neuronal excitability, seizure susceptibility, and spontaneous seizures, to determine how seizures alter mTOR Complex 1 (mTORC1) signaling. We hypothesized that seizures occurring at a developmental stage coinciding with a critical period of synaptogenesis will activate mTORC1, contributing to epileptic networks and autistic-like behavior in later life. Here we show that in the rat, baseline mTORC1 activation peaks during the first three postnatal weeks, and induction of seizures at postnatal day 10 results in further transient activation of its downstream targets phospho-4E-BP1 (Thr37/46), phospho-p70S6K (Thr389) and phospho-S6 (Ser235/236), as well as rapid induction of activity-dependent upstream signaling molecules, including BDNF, phospho-Akt (Thr308) and phospho-ERK (Thr202/Tyr204). Furthermore, treatment with the mTORC1 inhibitor rapamycin immediately before and after seizures reversed early increases in glutamatergic neurotransmission and seizure susceptibility and attenuated later life epilepsy and autistic-like behavior. Together, these findings suggest that in the developing brain the mTORC1 signaling pathway is involved in epileptogenesis and altered social behavior, and that it may be a target for development of novel therapies that eliminate the progressive effects of neonatal seizures.

  6. The Interaction between Early Life Epilepsy and Autistic-Like Behavioral Consequences: A Role for the Mammalian Target of Rapamycin (mTOR) Pathway

    PubMed Central

    Fitzgerald, Erin C.; Jackson, Michele C.; Klein, Peter M.; Lan, Victor J.; Joseph, Annelise; Jensen, Frances E.

    2012-01-01

    Early life seizures can result in chronic epilepsy, cognitive deficits and behavioral changes such as autism, and conversely epilepsy is common in autistic children. We hypothesized that during early brain development, seizures could alter regulators of synaptic development and underlie the interaction between epilepsy and autism. The mammalian Target of Rapamycin (mTOR) modulates protein translation and is dysregulated in Tuberous Sclerosis Complex, a disorder characterized by epilepsy and autism. We used a rodent model of acute hypoxia-induced neonatal seizures that results in long term increases in neuronal excitability, seizure susceptibility, and spontaneous seizures, to determine how seizures alter mTOR Complex 1 (mTORC1) signaling. We hypothesized that seizures occurring at a developmental stage coinciding with a critical period of synaptogenesis will activate mTORC1, contributing to epileptic networks and autistic-like behavior in later life. Here we show that in the rat, baseline mTORC1 activation peaks during the first three postnatal weeks, and induction of seizures at postnatal day 10 results in further transient activation of its downstream targets phospho-4E-BP1 (Thr37/46), phospho-p70S6K (Thr389) and phospho-S6 (Ser235/236), as well as rapid induction of activity-dependent upstream signaling molecules, including BDNF, phospho-Akt (Thr308) and phospho-ERK (Thr202/Tyr204). Furthermore, treatment with the mTORC1 inhibitor rapamycin immediately before and after seizures reversed early increases in glutamatergic neurotransmission and seizure susceptibility and attenuated later life epilepsy and autistic-like behavior. Together, these findings suggest that in the developing brain the mTORC1 signaling pathway is involved in epileptogenesis and altered social behavior, and that it may be a target for development of novel therapies that eliminate the progressive effects of neonatal seizures. PMID:22567115

  7. Temporally Distinct Six2-Positive Second Heart Field Progenitors Regulate Mammalian Heart Development and Disease.

    PubMed

    Zhou, Zhengfang; Wang, Jingying; Guo, Chaoshe; Chang, Weiting; Zhuang, Jian; Zhu, Ping; Li, Xue

    2017-01-24

    The embryonic process of forming a complex structure such as the heart remains poorly understood. Here, we show that Six2 marks a dynamic subset of second heart field progenitors. Six2-positive (Six2 + ) progenitors are rapidly recruited and assigned, and their descendants are allocated successively to regions of the heart from the right ventricle (RV) to the pulmonary trunk. Global ablation of Six2 + progenitors resulted in RV hypoplasia and pulmonary atresia. An early stage-specific ablation of a small subset of Six2 + progenitors did not cause any apparent structural defect at birth but rather resulted in adult-onset cardiac hypertrophy and dysfunction. Furthermore, Six2 expression depends in part on Shh signaling, and Shh deletion resulted in severe deficiency of Six2 + progenitors. Collectively, these findings unveil the chronological features of cardiogenesis, in which the mammalian heart is built sequentially by temporally distinct populations of cardiac progenitors, and provide insights into late-onset congenital heart disease. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  8. Calcium at fertilization and in early development

    PubMed Central

    Whitaker, Michael

    2012-01-01

    Fertilization calcium waves are introduced and the evidence from which we can infer general mechanisms of these waves is presented. The two main classes of hypothesis put forward to explain the generation of the fertilization calcium wave are set out and it is concluded that initiation of the fertilization calcium wave can be most generally explained in inverterbrates by a mechanism in which an activating substance enters the egg from the sperm on sperm-egg fusion, activating the egg by stimulating phospholipase C activation through a src family kinase pathway and in mammals by the diffusion of a sperm-specific phospholipase C from sperm to egg on sperm-egg fusion. The fertilization calcium wave is then set into the context of cell cycle control and the mechanism of repetitive calcium spiking in mammalian eggs is investigated. Evidence that calcium signals control cell division in early embryos is reviewed, and it is concluded that calcium signals are essential at all three stages of cell division in early embryos. Evidence that phosphoinositide signalling pathways control the resumption of meiosis during oocyte maturation is considered. It is concluded on balance that the evidence points to a need for phosphoinositide/calcium signalling during resumption of meiosis. Changes to the calcium signalling machinery occur during meiosis to enable the production of a calcium wave in the mature oocyte when it is fertilized; evidence that the shape and structure of the endoplasmic reticulum alters dynamically during maturation and after fertilization is reviewed and the link between ER dynamics and the cytoskeleton is discussed. There is evidence that calcium signalling plays a key part in the development of patterning in early embryos. Morphogenesis in ascidian, frog and zebrafish embryos is briefly described to provide the developmental context in which calcium signals act. Intracellular calcium waves that may play a role in axis formation in ascidian are discussed

  9. Cognitive Development in Early Readers.

    ERIC Educational Resources Information Center

    Briggs, Chari; Elkind, David

    Some studies of early readers are discussed. It is pointed out that study of early readers has relevance for practical and theoretical issues in psychology and education. Of interest in this document are the following questions: (1) Are there any special talents or traits distinguishing early from non-early readers? (2) Do children who read early…

  10. [Early childhood growth and development].

    PubMed

    Arce, Melitón

    2015-01-01

    This article describes and discusses issues related to the process of childhood growth and development, with emphasis on the early years, a period in which this process reaches critical speed on major structures and functions of the human economy. We reaffirm that this can contribute to the social availability of a generation of increasingly better adults, which in turn will be able to contribute to building a better world and within it a society that enjoys greater prosperity. In the first chapter, we discuss the general considerations on the favorable evolution of human society based on quality of future adults, meaning the accomplishments that today’s children will gain. A second chapter mentions the basics of growth and development in the different fields and the various phenomena that occur in it. In the third we refer to lost opportunities and negative factors that can affect delaying the process and thereby result in not obtaining the expected accomplishments. In the fourth, conclusions and recommendations are presented confirming the initial conception that good early child care serves to build a better society and some recommendations are formulated to make it a good practice.

  11. Calcium signaling in mammalian egg activation and embryo development: Influence of subcellular localization

    PubMed Central

    Miao, Yi-Liang; Williams, Carmen J.

    2012-01-01

    Calcium (Ca2+) signals drive the fundamental events surrounding fertilization and the activation of development in all species examined to date. Initial studies of Ca2+ signaling at fertilization in marine animals were tightly linked to new discoveries of bioluminescent proteins and their use as fluorescent Ca2+ sensors. Since that time, there has been rapid progress in our understanding of the key functions for Ca2+ in many cell types and the impact of cellular localization on Ca2+ signaling pathways. In this review, which focuses on mammalian egg activation, we consider how Ca2+ is regulated and stored at different stages of oocyte development and examine the functions of molecules that serve as both regulators of Ca2+ release and effectors of Ca2+ signals. We then summarize studies exploring how Ca2+ directs downstream effectors mediating both egg activation and later signaling events required for successful preimplantation embryo development. Throughout this review, we focus attention on how localization of Ca2+ signals influences downstream signaling events, and attempt to highlight gaps in our knowledge that are ripe areas for future research. PMID:22888043

  12. Product quality considerations for mammalian cell culture process development and manufacturing.

    PubMed

    Gramer, Michael J

    2014-01-01

    The manufacturing of a biologic drug from mammalian cells results in not a single substance, but an array of product isoforms, also known as variants. These isoforms arise due to intracellular or extracellular events as a result of biological or chemical modification. The most common examples related to biomanufacturing include amino acid modifications (glycosylation, isomerization, oxidation, adduct formation, pyroglutamate formation, phosphorylation, sulfation, amidation), amino acid sequence variants (genetic mutations, amino acid misincorporation, N- and C-terminal heterogeneity, clipping), and higher-order structure modifications (misfolding, aggregation, disulfide pairing). Process-related impurities (HCP, DNA, media components, viral particles) are also important quality attributes related to product safety. The observed ranges associated with each quality attribute define the product quality profile. A biologic drug must have a correct and consistent quality profile throughout clinical development and scale-up to commercial production to ensure product safety and efficacy. In general, the upstream process (cell culture) defines the quality of product-related substances, whereas the downstream process (purification) defines the residual level of process- and product-related impurities. The purpose of this chapter is to review the impact of the cell culture process on product quality. Emphasis is placed on studies with industrial significance and where the direct mechanism of product quality impact was determined. Where possible, recommendations for maintaining consistent or improved quality are provided.

  13. Epigenetic regulation of Atoh1 guides hair cell development in the mammalian cochlea.

    PubMed

    Stojanova, Zlatka P; Kwan, Tao; Segil, Neil

    2015-10-15

    In the developing cochlea, sensory hair cell differentiation depends on the regulated expression of the bHLH transcription factor Atoh1. In mammals, if hair cells die they do not regenerate, leading to permanent deafness. By contrast, in non-mammalian vertebrates robust regeneration occurs through upregulation of Atoh1 in the surviving supporting cells that surround hair cells, leading to functional recovery. Investigation of crucial transcriptional events in the developing organ of Corti, including those involving Atoh1, has been hampered by limited accessibility to purified populations of the small number of cells present in the inner ear. We used µChIP and qPCR assays of FACS-purified cells to track changes in the epigenetic status of the Atoh1 locus during sensory epithelia development in the mouse. Dynamic changes in the histone modifications H3K4me3/H3K27me3, H3K9ac and H3K9me3 reveal a progression from poised, to active, to repressive marks, correlating with the onset of Atoh1 expression and its subsequent silencing during the perinatal (P1 to P6) period. Inhibition of acetylation blocked the increase in Atoh1 mRNA in nascent hair cells, as well as ongoing hair cell differentiation during embryonic organ of Corti development ex vivo. These results reveal an epigenetic mechanism of Atoh1 regulation underlying hair cell differentiation and subsequent maturation. Interestingly, the H3K4me3/H3K27me3 bivalent chromatin structure observed in progenitors persists at the Atoh1 locus in perinatal supporting cells, suggesting an explanation for the latent capacity of these cells to transdifferentiate into hair cells, and highlighting their potential as therapeutic targets in hair cell regeneration. © 2015. Published by The Company of Biologists Ltd.

  14. Taiwanese Early Childhood Educators' Professional Development

    ERIC Educational Resources Information Center

    Hsu, Ching-Yun

    2008-01-01

    This study was designed based on a qualitative paradigm to explore the professional development of Taiwanese early childhood educators. The method of phenomenology was employed. The main research question addressed was "How do early childhood educators construe their professional development experience?" Seven Taiwanese early childhood…

  15. Early Childhood Diplomacy: Policy Planning for Early Childhood Development

    ERIC Educational Resources Information Center

    Vargas-Barón, Emily; Diehl, Kristel

    2018-01-01

    Children who are well nurtured, appropriately cared for, and provided with positive learning opportunities in their early years have a better chance of becoming healthy and productive citizens of nations and of the world. This article reviews the art and science of policy planning for early childhood development (ECD) from a diplomacy perspective.…

  16. Behavioral development in embryonic and early juvenile cuttlefish (Sepia officinalis).

    PubMed

    O'Brien, Caitlin E; Mezrai, Nawel; Darmaillacq, Anne-Sophie; Dickel, Ludovic

    2017-03-01

    Though a mollusc, the cuttlefish Sepia officinalis possesses a sophisticated brain, advanced sensory systems, and a large behavioral repertoire. Cuttlefish provide a unique perspective on animal behavior due to their phylogenic distance from more traditional (vertebrate) models. S. officinalis is well-suited to addressing questions of behavioral ontogeny. As embryos, they can perceive and learn from their environment and experience no direct parental care. A marked progression in learning and behavior is observed during late embryonic and early juvenile development. This improvement is concomitant with expansion and maturation of the vertical lobe, the cephalopod analog of the mammalian hippocampus. This review synthesizes existing knowledge regarding embryonic and juvenile development in this species in an effort to better understand cuttlefish behavior and animal behavior in general. It will serve as a guide to future researchers and encourage greater awareness of the utility of this species to behavioral science. © 2016 Wiley Periodicals, Inc.

  17. Transposable elements as genetic regulatory substrates in early development.

    PubMed

    Gifford, Wesley D; Pfaff, Samuel L; Macfarlan, Todd S

    2013-05-01

    The abundance and ancient origins of transposable elements (TEs) in eukaryotic genomes has spawned research into the potential symbiotic relationship between these elements and their hosts. In this review, we introduce the diversity of TEs, discuss how distinct classes are uniquely regulated in development, and describe how they appear to have been coopted for the purposes of gene regulation and the orchestration of a number of processes during early embryonic development. Although young, active TEs play an important role in somatic tissues and evolution, we focus mostly on the contributions of the older, fixed elements in mammalian genomes. We also discuss major challenges inherent in the study of TEs and contemplate future experimental approaches to further investigate how they coordinate developmental processes. Published by Elsevier Ltd.

  18. Transposable elements as genetic regulatory substrates in early development

    PubMed Central

    Gifford, Wesley D.; Pfaff, Samuel L.; Macfarlan, Todd S.

    2014-01-01

    The abundance and ancient origins of transposable elements (TEs) in eukaryotic genomes has spawned research into the potential symbiotic relationship between these elements and their hosts. In this review, we introduce the diversity of TEs, discuss how distinct classes are uniquely regulated in development, and describe how they appear to have been coopted for the purposes of gene regulation and the orchestration of a number of processes during early embryonic development. Although young, active TEs play an important role in somatic tissues and evolution, we focus mostly on the contributions of the older, fixed elements in mammalian genomes. We also discuss major challenges inherent in the study of TEs and contemplate future experimental approaches to further investigate how they coordinate developmental processes. PMID:23411159

  19. Regulation of prohibitin expression during follicular development and atresia in the mammalian ovary.

    PubMed

    Thompson, Winston E; Asselin, Eric; Branch, Alicia; Stiles, Jonathan K; Sutovsky, Peter; Lai, Liangxue; Im, Gi-Sun; Prather, Randall S; Isom, S Clay; Rucker, Edmund; Tsang, Benjamin K

    2004-07-01

    Prohibitin is a ubiquitous and highly conserved protein implicated as an important regulator in cell survival. Prohibitin content is inversely associated with cell proliferation, but it increases during granulosa cell differentiation as well as in earlier events of apoptosis in a temperature-sensitive granulosa cell line. In the present study, we have characterized the spatial expression patterns for prohibitin using established in vivo models for the induction of follicular development and atresia in the mammalian ovary. Comparative Western blot analyses of granulosa cell lysates from control ovaries and from ovaries primed with eCG or treated with eCG plus anti-eCG (gonadotropin withdrawal) were conducted. Prohibitin was immunolocalized in rat ovarian sections probed with antibodies against either proliferating cell nuclear antigen (PCNA) or cholesterol side-chain cleavage cytochrome P450 (P450(scc)) or in terminal deoxynucleotidyl transferase-mediated dUTP nick end labeled sections. Additionally, porcine oocytes, zygotes, and blastocyts were also immunolocalized with prohibitin antibody. Immunolocalization revealed the presence of prohibitin in granulosa cells, theca-interstitial cells, and the oocyte. The results indicate that prohibitin protein expression in the gonadotropin-treated cells was upregulated. Immunoreactivity of prohibitin was inversely related to PCNA expression during follicular maturation and colocalized with P450(scc). Prohibitin appeared to be translocated from the cytoplasm to the nucleus in atretic follicles, germinal vesicle-stage oocytes, zygotes, and blastocysts. These results suggest that prohibitin has several functional regulatory roles in granulosa and theca-interstitial cells and in the ovum during follicular maturation and atresia. It is likely that prohibitin may play an important role in determining the fate of these cells and eventual follicular destiny.

  20. DEVELOPMENT OF A REFINED DATABASE OF MAMMALIAN RELATIVE POTENCY ESTIMATES FOR DIOXIN-LIKE COMPOUNDS

    EPA Science Inventory

    The toxic equivalency factor (TEF) approach has been widely accepted as the most feasible method available at present for evaluating potential health risks associated with exposure to mixtures of dioxin-like compounds (DLCs). The current mammalian TEFs for the DLCs were establis...

  1. Kentucky's Statewide Early Childhood Professional Development System

    ERIC Educational Resources Information Center

    Rous, Beth; Grove, Jaime; Townley, Kim

    2007-01-01

    Public school systems have recently become major players in providing services for children in their early years. In addition, a number of other services are available to young children including child care, Head Start, and Early Head Start programs. The link between program quality and professional development of early care and education…

  2. Mammalian sleep

    NASA Astrophysics Data System (ADS)

    Staunton, Hugh

    2005-05-01

    This review examines the biological background to the development of ideas on rapid eye movement sleep (REM sleep), so-called paradoxical sleep (PS), and its relation to dreaming. Aspects of the phenomenon which are discussed include physiological changes and their anatomical location, the effects of total and selective sleep deprivation in the human and animal, and REM sleep behavior disorder, the latter with its clinical manifestations in the human. Although dreaming also occurs in other sleep phases (non-REM or NREM sleep), in the human, there is a contingent relation between REM sleep and dreaming. Thus, REM is taken as a marker for dreaming and as REM is distributed ubiquitously throughout the mammalian class, it is suggested that other mammals also dream. It is suggested that the overall function of REM sleep/dreaming is more important than the content of the individual dream; its function is to place the dreamer protagonist/observer on the topographical world. This has importance for the developing infant who needs to develop a sense of self and separateness from the world which it requires to navigate and from which it is separated for long periods in sleep. Dreaming may also serve to maintain a sense of ‘I’ness or “self” in the adult, in whom a fragility of this faculty is revealed in neurological disorders.

  3. Early development and replacement of the stickleback dentition

    PubMed Central

    Ellis, Nicholas A.; Donde, Nikunj N.; Miller, Craig T.

    2017-01-01

    Teeth have long served as a model system to study basic questions about vertebrate organogenesis, morphogenesis, and evolution. In non-mammalian vertebrates, teeth typically regenerate throughout adult life. Fish have evolved a tremendous diversity in dental patterning in both their oral and pharyngeal dentitions, offering numerous opportunities to study how morphology develops, regenerates, and evolves in different lineages. Threespine stickleback fish (Gasterosteus aculeatus) have emerged as a new system to study how morphology evolves, and provide a particularly powerful system to study the development and evolution of dental morphology. Here we describe the oral and pharyngeal dentitions of stickleback fish, providing additional morphological, histological, and molecular evidence for homology of oral and pharyngeal teeth. Focusing on the ventral pharyngeal dentition in a dense developmental time course of lab-reared fish, we describe the temporal and spatial consensus sequence of early tooth formation. Early in development, this sequence is highly stereotypical and consists of seventeen primary teeth forming the early tooth field, followed by the first tooth replacement event. Comparing this detailed morphological and ontogenetic sequence to that described in other fish reveals that major changes to how dental morphology arises and regenerates have evolved across different fish lineages. PMID:27145214

  4. Mammalian target of rapamycin is essential for cardiomyocyte survival and heart development in mice

    SciTech Connect

    Zhang, Pengpeng; Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070; Department of Animal Sciences, Purdue University, West Lafayette, IN 47907

    Highlights: • mTOR is a critical regulator of many biological processes yet its function in heart is not well understood. • MCK-Cre/Mtor{sup flox/flox} mice were established to delete Mtor in cardiomyocytes. • The mTOR-mKO mice developed normally but die prematurely within 5 weeks after birth due to heart disease. • The mTOR-mKO mice had dilated myocardium and increased cell death. • mTOR-mKO hearts had reduced expression of metabolic genes and activation of mTOR target proteins. - Abstract: Mammalian target of rapamycin (mTOR) is a critical regulator of protein synthesis, cell proliferation and energy metabolism. As constitutive knockout of Mtor leadsmore » to embryonic lethality, the in vivo function of mTOR in perinatal development and postnatal growth of heart is not well defined. In this study, we established a muscle-specific mTOR conditional knockout mouse model (mTOR-mKO) by crossing MCK-Cre and Mtor{sup flox/flox} mice. Although the mTOR-mKO mice survived embryonic and perinatal development, they exhibited severe postnatal growth retardation, cardiac muscle pathology and premature death. At the cellular level, the cardiac muscle of mTOR-mKO mice had fewer cardiomyocytes due to apoptosis and necrosis, leading to dilated cardiomyopathy. At the molecular level, the cardiac muscle of mTOR-mKO mice expressed lower levels of fatty acid oxidation and glycolysis related genes compared to the WT littermates. In addition, the mTOR-mKO cardiac muscle had reduced Myh6 but elevated Myh7 expression, indicating cardiac muscle degeneration. Furthermore, deletion of Mtor dramatically decreased the phosphorylation of S6 and AKT, two key targets downstream of mTORC1 and mTORC2 mediating the normal function of mTOR. These results demonstrate that mTOR is essential for cardiomyocyte survival and cardiac muscle function.« less

  5. The Development of STAR Early Literacy. Report.

    ERIC Educational Resources Information Center

    School Renaissance Inst., Inc., Madison, WI.

    This report describes the development and testing of a computerized early literacy diagnostic assessment for students in prekindergarten to grade 3 that can measure skills across a variety of preliteracy and reading domains. The STAR Early Literacy assessment was developed by a team of more than 50 people, including literacy experts,…

  6. Critical Issues in Early Childhood Professional Development

    ERIC Educational Resources Information Center

    Zaslow, Martha, Ed.; Martinez-Beck, Ivelisse, Ed.

    2005-01-01

    Effective teaching leads to positive student outcomes, and professional development for early childhood teachers is key to improving both. But what exactly is meant by "professional development"? What effect does it have on school readiness? Which models and approaches really work? This is the book the early childhood field needs to take the…

  7. Evaluation of Selected Borrelia burgdorferi lp54 Plasmid-Encoded Gene Products Expressed during Mammalian Infection as Antigens To Improve Serodiagnostic Testing for Early Lyme Disease

    PubMed Central

    Weiner, Zachary P.; Crew, Rebecca M.; Brandt, Kevin S.; Ullmann, Amy J.; Schriefer, Martin E.; Molins, Claudia R.

    2015-01-01

    Laboratory testing for the diagnosis of Lyme disease is performed primarily by serologic assays and is accurate for detection beyond the acute stage of the infection. Serodiagnostic assays to detect the early stages of infection, however, are limited in their sensitivity, and improvement is warranted. We analyzed a series of Borrelia burgdorferi proteins known to be induced within feeding ticks and/or during mammalian infection for their utility as serodiagnostic markers against a comprehensive panel of Lyme disease patient serum samples. The antigens were assayed for IgM and IgG reactivity in line immunoblots and separately by enzyme-linked immunosorbent assay (ELISA), with a focus on reactivity against early Lyme disease with erythema migrans (EM), early disseminated Lyme neuroborreliosis, and early Lyme carditis patient serum samples. By IgM immunoblotting, we found that recombinant proteins BBA65, BBA70, and BBA73 reacted with early Lyme EM samples at levels comparable to those of the OspC antigen used in the current IgM blotting criteria. Additionally, these proteins reacted with serum samples from patients with early neuroborreliosis and early carditis, suggesting value in detecting early stages of this disease progression. We also found serological reactivity against recombinant proteins BBA69 and BBA73 with early-Lyme-disease samples using IgG immunoblotting and ELISA. Significantly, some samples that had been scored negative by the Centers for Disease Control and Prevention-recommended 2-tiered testing algorithm demonstrated positive reactivity to one or more of the antigens by IgM/IgG immunoblot and ELISA. These results suggest that incorporating additional in vivo-expressed antigens into the current IgM/IgG immunoblotting tier in a recombinant protein platform assay may improve the performance of early-Lyme-disease serologic testing. PMID:26376927

  8. Evaluation of Selected Borrelia burgdorferi lp54 Plasmid-Encoded Gene Products Expressed during Mammalian Infection as Antigens To Improve Serodiagnostic Testing for Early Lyme Disease.

    PubMed

    Weiner, Zachary P; Crew, Rebecca M; Brandt, Kevin S; Ullmann, Amy J; Schriefer, Martin E; Molins, Claudia R; Gilmore, Robert D

    2015-11-01

    Laboratory testing for the diagnosis of Lyme disease is performed primarily by serologic assays and is accurate for detection beyond the acute stage of the infection. Serodiagnostic assays to detect the early stages of infection, however, are limited in their sensitivity, and improvement is warranted. We analyzed a series of Borrelia burgdorferi proteins known to be induced within feeding ticks and/or during mammalian infection for their utility as serodiagnostic markers against a comprehensive panel of Lyme disease patient serum samples. The antigens were assayed for IgM and IgG reactivity in line immunoblots and separately by enzyme-linked immunosorbent assay (ELISA), with a focus on reactivity against early Lyme disease with erythema migrans (EM), early disseminated Lyme neuroborreliosis, and early Lyme carditis patient serum samples. By IgM immunoblotting, we found that recombinant proteins BBA65, BBA70, and BBA73 reacted with early Lyme EM samples at levels comparable to those of the OspC antigen used in the current IgM blotting criteria. Additionally, these proteins reacted with serum samples from patients with early neuroborreliosis and early carditis, suggesting value in detecting early stages of this disease progression. We also found serological reactivity against recombinant proteins BBA69 and BBA73 with early-Lyme-disease samples using IgG immunoblotting and ELISA. Significantly, some samples that had been scored negative by the Centers for Disease Control and Prevention-recommended 2-tiered testing algorithm demonstrated positive reactivity to one or more of the antigens by IgM/IgG immunoblot and ELISA. These results suggest that incorporating additional in vivo-expressed antigens into the current IgM/IgG immunoblotting tier in a recombinant protein platform assay may improve the performance of early-Lyme-disease serologic testing. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Oxidized Base Damage and Single-Strand Break Repair in Mammalian Genomes: Role of Disordered Regions and Posttranslational Modifications in Early Enzymes

    PubMed Central

    Hegde, Muralidhar L.; Izumi, Tadahide; Mitra, Sankar

    2012-01-01

    Oxidative genome damage induced by reactive oxygen species includes oxidized bases, abasic (AP) sites, and single-strand breaks, all of which are repaired via the evolutionarily conserved base excision repair/single-strand break repair (BER/SSBR) pathway. BER/SSBR in mammalian cells is complex, with preferred and backup sub-pathways, and is linked to genome replication and transcription. The early BER/SSBR enzymes, namely, DNA glycosylases (DGs) and the end-processing proteins such as abasic endonuclease 1 (APE1), form complexes with downstream repair (and other noncanonical) proteins via pairwise interactions. Furthermore, a unique feature of mammalian early BER/ SSBR enzymes is the presence of a disordered terminal extension that is absent in their Escherichia coli prototypes. These nonconserved segments usually contain organelle-targeting signals, common interaction interfaces, and sites of posttranslational modifications that may be involved in regulating their repair function including lesion scanning. Finally, the linkage of BER/SSBR deficiency to cancer, aging, and human neurodegenerative diseases, and therapeutic targeting of BER/SSBR are discussed. PMID:22749145

  10. Control of early seed development.

    PubMed

    Chaudhury, A M; Koltunow, A; Payne, T; Luo, M; Tucker, M R; Dennis, E S; Peacock, W J

    2001-01-01

    Seed development requires coordinated expression of embryo and endosperm and has contributions from both sporophytic and male and female gametophytic genes. Genetic and molecular analyses in recent years have started to illuminate how products of these multiple genes interact to initiate seed development. Imprinting or differential expression of paternal and maternal genes seems to be involved in controlling seed development, presumably by controlling gene expression in developing endosperm. Epigenetic processes such as chromatin remodeling and DNA methylation affect imprinting of key seed-specific genes; however, the identity of many of these genes remains unknown. The discovery of FIS genes has illuminated control of autonomous endosperm development, a component of apomixis, which is an important developmental and agronomic trait. FIS genes are targets of imprinting, and the genes they control in developing endosperm are also regulated by DNA methylation and chromatin remodeling genes. These results define some exciting future areas of research in seed development.

  11. Genome sequence of an Australian kangaroo, Macropus eugenii, provides insight into the evolution of mammalian reproduction and development

    PubMed Central

    2011-01-01

    Background We present the genome sequence of the tammar wallaby, Macropus eugenii, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced. The tammar has many unusual biological characteristics, including the longest period of embryonic diapause of any mammal, extremely synchronized seasonal breeding and prolonged and sophisticated lactation within a well-defined pouch. Like other marsupials, it gives birth to highly altricial young, and has a small number of very large chromosomes, making it a valuable model for genomics, reproduction and development. Results The genome has been sequenced to 2 × coverage using Sanger sequencing, enhanced with additional next generation sequencing and the integration of extensive physical and linkage maps to build the genome assembly. We also sequenced the tammar transcriptome across many tissues and developmental time points. Our analyses of these data shed light on mammalian reproduction, development and genome evolution: there is innovation in reproductive and lactational genes, rapid evolution of germ cell genes, and incomplete, locus-specific X inactivation. We also observe novel retrotransposons and a highly rearranged major histocompatibility complex, with many class I genes located outside the complex. Novel microRNAs in the tammar HOX clusters uncover new potential mammalian HOX regulatory elements. Conclusions Analyses of these resources enhance our understanding of marsupial gene evolution, identify marsupial-specific conserved non-coding elements and critical genes across a range of biological systems, including reproduction, development and immunity, and provide new insight into marsupial and mammalian biology and genome evolution. PMID:21854559

  12. Genome sequence of an Australian kangaroo, Macropus eugenii, provides insight into the evolution of mammalian reproduction and development.

    PubMed

    Renfree, Marilyn B; Papenfuss, Anthony T; Deakin, Janine E; Lindsay, James; Heider, Thomas; Belov, Katherine; Rens, Willem; Waters, Paul D; Pharo, Elizabeth A; Shaw, Geoff; Wong, Emily S W; Lefèvre, Christophe M; Nicholas, Kevin R; Kuroki, Yoko; Wakefield, Matthew J; Zenger, Kyall R; Wang, Chenwei; Ferguson-Smith, Malcolm; Nicholas, Frank W; Hickford, Danielle; Yu, Hongshi; Short, Kirsty R; Siddle, Hannah V; Frankenberg, Stephen R; Chew, Keng Yih; Menzies, Brandon R; Stringer, Jessica M; Suzuki, Shunsuke; Hore, Timothy A; Delbridge, Margaret L; Patel, Hardip R; Mohammadi, Amir; Schneider, Nanette Y; Hu, Yanqiu; O'Hara, William; Al Nadaf, Shafagh; Wu, Chen; Feng, Zhi-Ping; Cocks, Benjamin G; Wang, Jianghui; Flicek, Paul; Searle, Stephen M J; Fairley, Susan; Beal, Kathryn; Herrero, Javier; Carone, Dawn M; Suzuki, Yutaka; Sugano, Sumio; Toyoda, Atsushi; Sakaki, Yoshiyuki; Kondo, Shinji; Nishida, Yuichiro; Tatsumoto, Shoji; Mandiou, Ion; Hsu, Arthur; McColl, Kaighin A; Lansdell, Benjamin; Weinstock, George; Kuczek, Elizabeth; McGrath, Annette; Wilson, Peter; Men, Artem; Hazar-Rethinam, Mehlika; Hall, Allison; Davis, John; Wood, David; Williams, Sarah; Sundaravadanam, Yogi; Muzny, Donna M; Jhangiani, Shalini N; Lewis, Lora R; Morgan, Margaret B; Okwuonu, Geoffrey O; Ruiz, San Juana; Santibanez, Jireh; Nazareth, Lynne; Cree, Andrew; Fowler, Gerald; Kovar, Christie L; Dinh, Huyen H; Joshi, Vandita; Jing, Chyn; Lara, Fremiet; Thornton, Rebecca; Chen, Lei; Deng, Jixin; Liu, Yue; Shen, Joshua Y; Song, Xing-Zhi; Edson, Janette; Troon, Carmen; Thomas, Daniel; Stephens, Amber; Yapa, Lankesha; Levchenko, Tanya; Gibbs, Richard A; Cooper, Desmond W; Speed, Terence P; Fujiyama, Asao; Graves, Jennifer A M; O'Neill, Rachel J; Pask, Andrew J; Forrest, Susan M; Worley, Kim C

    2011-08-29

    We present the genome sequence of the tammar wallaby, Macropus eugenii, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced. The tammar has many unusual biological characteristics, including the longest period of embryonic diapause of any mammal, extremely synchronized seasonal breeding and prolonged and sophisticated lactation within a well-defined pouch. Like other marsupials, it gives birth to highly altricial young, and has a small number of very large chromosomes, making it a valuable model for genomics, reproduction and development. The genome has been sequenced to 2 × coverage using Sanger sequencing, enhanced with additional next generation sequencing and the integration of extensive physical and linkage maps to build the genome assembly. We also sequenced the tammar transcriptome across many tissues and developmental time points. Our analyses of these data shed light on mammalian reproduction, development and genome evolution: there is innovation in reproductive and lactational genes, rapid evolution of germ cell genes, and incomplete, locus-specific X inactivation. We also observe novel retrotransposons and a highly rearranged major histocompatibility complex, with many class I genes located outside the complex. Novel microRNAs in the tammar HOX clusters uncover new potential mammalian HOX regulatory elements. Analyses of these resources enhance our understanding of marsupial gene evolution, identify marsupial-specific conserved non-coding elements and critical genes across a range of biological systems, including reproduction, development and immunity, and provide new insight into marsupial and mammalian biology and genome evolution.

  13. Optical coherence microscopy as a novel, non-invasive method for the 4D live imaging of early mammalian embryos.

    PubMed

    Karnowski, Karol; Ajduk, Anna; Wieloch, Bartosz; Tamborski, Szymon; Krawiec, Krzysztof; Wojtkowski, Maciej; Szkulmowski, Maciej

    2017-06-23

    Imaging of living cells based on traditional fluorescence and confocal laser scanning microscopy has delivered an enormous amount of information critical for understanding biological processes in single cells. However, the requirement for a high numerical aperture and fluorescent markers still limits researchers' ability to visualize the cellular architecture without causing short- and long-term photodamage. Optical coherence microscopy (OCM) is a promising alternative that circumvents the technical limitations of fluorescence imaging techniques and provides unique access to fundamental aspects of early embryonic development, without the requirement for sample pre-processing or labeling. In the present paper, we utilized the internal motion of cytoplasm, as well as custom scanning and signal processing protocols, to effectively reduce the speckle noise typical for standard OCM and enable high-resolution intracellular time-lapse imaging. To test our imaging system we used mouse and pig oocytes and embryos and visualized them through fertilization and the first embryonic division, as well as at selected stages of oogenesis and preimplantation development. Because all morphological and morphokinetic properties recorded by OCM are believed to be biomarkers of oocyte/embryo quality, OCM may represent a new chapter in imaging-based preimplantation embryo diagnostics.

  14. Elevated aminopeptidase N affects sperm motility and early embryo development

    PubMed Central

    Ryu, Do-Yeal; Kwon, Woo-Sung

    2017-01-01

    Aminopeptidase N (APN) is a naturally occurring ectopeptidase present in mammalian semen. Previous studies have demonstrated that APN adversely affects male fertility through the alteration of sperm motility. This enzyme constitutes 0.5 to 1% of the seminal plasma proteins, which can be transferred from the prostasomes to sperms by a fusion process. In the present study, we investigated the molecular mechanism of action of APN and its role in regulating sperm functions and male fertility. In this in vitro study, epididymal mouse spermatozoa were incubated in a capacitating media (pH 7) containing 20 ng/mL of recombinant mouse APN for 90 min. Our results demonstrated that the supplementation of recombinant APN in sperm culture medium significantly increased APN activity, and subsequently altered motility, hyperactivated motility, rapid and medium swimming speeds, viability, and the acrosome reaction of mouse spermatozoa. These effects were potentially caused by increased toxicity in the spermatozoa. Further, altered APN activity in sperm culture medium affected early embryonic development. Interestingly, the effect of elevated APN activity in sperm culture medium was independent of protein tyrosine phosphorylation and protein kinase A activity. On the basis of these results, we concluded that APN plays a significant role in the regulation of several sperm functions and early embryonic development. In addition, increased APN activity could potentially lead to several adverse consequences related to male fertility. PMID:28859152

  15. Dual effects of fluoxetine on mouse early embryonic development.

    PubMed

    Kim, Chang-Woon; Choe, Changyong; Kim, Eun-Jin; Lee, Jae-Ik; Yoon, Sook-Young; Cho, Young-Woo; Han, Sunkyu; Tak, Hyun-Min; Han, Jaehee; Kang, Dawon

    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 50μM) for different durations. When late 2-cells were incubated with 5μM fluoxetine for 6h, the percentage that developed into blastocysts increased compared to the control value. However, late 2-cells exposed to fluoxetine (5μM) over 24h showed a reduction in blastocyst formation. The addition of fluoxetine (5μM) 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(+) 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. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Recent advances on the role of long non-coding RNA H19 in regulating mammalian muscle growth and development.

    PubMed

    Qin, Chen Yu; Cai, He; Qing, Han Rui; Li, Li; Zhang, Hong Ping

    2017-12-20

    As one of the first identified long non-coding RNAs (lncRNAs), H19 plays a wide range of roles in vivo, including not only as a tumor suppressor and oncogene involved in disease process, but also as a regulator of growth and development of multiple tissues in mammalian embryos. The function of H19 in muscles (both skeletal and cardiac muscle) draws widespread attention due to the following two reasons. On one hand, H19 promotes myogenic differentiation and myogenesis of skeletal muscle satellite cells (SMSCs) via regulating Igf2 in cis. On the other hand, H19 also modulates the target genes in trans, including sponging let-7, miR-106 or miR-29 to mediate myocyte glucose uptake, cardiomyocyte proliferation and tendon repair, as well as promote embryonic development and muscle regeneration through binding to MBD1 as a chromatin modifier. In this review, we summarize the role of H19 in mammalian muscles, which will provide a reference for further research to unveil the molecular mechanism of muscle growth and development.

  17. Inhibition of mammalian target of rapamycin attenuates early brain injury through modulating microglial polarization after experimental subarachnoid hemorrhage in rats.

    PubMed

    You, Wanchun; Wang, Zhong; Li, Haiying; Shen, Haitao; Xu, Xiang; Jia, Genlai; Chen, Gang

    2016-08-15

    Here, we aimed to study the role and underlying mechanism of mTOR in early brain injury (EBI) after subarachnoid hemorrhage (SAH). Experiment 1, the time course of mTOR activation in the cortex following SAH. Experiment 2, the role of mTOR in SAH-induced EBI. Adult SD rats were divided into four groups: sham group (n=18), SAH+vehicle group (n=18), SAH+rapamycin group (n=18), SAH+AZD8055 group (n=18). Experiment 3, we incubated enriched microglia with OxyHb. Rapamycin and AZD8055 were also used to demonstrate the mTOR's role on microglial polarization in vitro. The phosphorylation levels of mTOR and its substrates were significantly increased and peaked at 24h after SAH. Rapamycin or AZD8055 markedly decreased the phosphorylation levels of mTOR and its substrates and the activation of microglia in vivo, and promoted the microglial polarization from M1 phenotype to M2 phenotype. In addition, administration of rapamycin and AZD8055 following SAH significantly ameliorated EBI, including neuronal apoptosis, neuronal necrosis, brain edema and blood-brain barrier permeability. Our findings suggested that the rapamycin and AZD8055 could attenuate the development of EBI in this SAH model, possibly through inhibiting the activation of microglia by mTOR pathway. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Enzymatic Removal of Ribonucleotides from DNA Is Essential for Mammalian Genome Integrity and Development

    PubMed Central

    Reijns, Martin A.M.; Rabe, Björn; Rigby, Rachel E.; Mill, Pleasantine; Astell, Katy R.; Lettice, Laura A.; Boyle, Shelagh; Leitch, Andrea; Keighren, Margaret; Kilanowski, Fiona; Devenney, Paul S.; Sexton, David; Grimes, Graeme; Holt, Ian J.; Hill, Robert E.; Taylor, Martin S.; Lawson, Kirstie A.; Dorin, Julia R.; Jackson, Andrew P.

    2012-01-01

    Summary The presence of ribonucleotides in genomic DNA is undesirable given their increased susceptibility to hydrolysis. Ribonuclease (RNase) H enzymes that recognize and process such embedded ribonucleotides are present in all domains of life. However, in unicellular organisms such as budding yeast, they are not required for viability or even efficient cellular proliferation, while in humans, RNase H2 hypomorphic mutations cause the neuroinflammatory disorder Aicardi-Goutières syndrome. Here, we report that RNase H2 is an essential enzyme in mice, required for embryonic growth from gastrulation onward. RNase H2 null embryos accumulate large numbers of single (or di-) ribonucleotides embedded in their genomic DNA (>1,000,000 per cell), resulting in genome instability and a p53-dependent DNA-damage response. Our findings establish RNase H2 as a key mammalian genome surveillance enzyme required for ribonucleotide removal and demonstrate that ribonucleotides are the most commonly occurring endogenous nucleotide base lesion in replicating cells. PMID:22579044

  19. Development of coherent neuronal activity patterns in mammalian cortical networks: common principles and local hetereogeneity.

    PubMed

    Egorov, Alexei V; Draguhn, Andreas

    2013-01-01

    Many mammals are born in a very immature state and develop their rich repertoire of behavioral and cognitive functions postnatally. This development goes in parallel with changes in the anatomical and functional organization of cortical structures which are involved in most complex activities. The emerging spatiotemporal activity patterns in multi-neuronal cortical networks may indeed form a direct neuronal correlate of systemic functions like perception, sensorimotor integration, decision making or memory formation. During recent years, several studies--mostly in rodents--have shed light on the ontogenesis of such highly organized patterns of network activity. While each local network has its own peculiar properties, some general rules can be derived. We therefore review and compare data from the developing hippocampus, neocortex and--as an intermediate region--entorhinal cortex. All cortices seem to follow a characteristic sequence starting with uncorrelated activity in uncoupled single neurons where transient activity seems to have mostly trophic effects. In rodents, before and shortly after birth, cortical networks develop weakly coordinated multineuronal discharges which have been termed synchronous plateau assemblies (SPAs). While these patterns rely mostly on electrical coupling by gap junctions, the subsequent increase in number and maturation of chemical synapses leads to the generation of large-scale coherent discharges. These patterns have been termed giant depolarizing potentials (GDPs) for predominantly GABA-induced events or early network oscillations (ENOs) for mostly glutamatergic bursts, respectively. During the third to fourth postnatal week, cortical areas reach their final activity patterns with distinct network oscillations and highly specific neuronal discharge sequences which support adult behavior. While some of the mechanisms underlying maturation of network activity have been elucidated much work remains to be done in order to fully

  20. Mammalian Pheromones

    PubMed Central

    Liberles, Stephen D.

    2015-01-01

    Mammalian pheromones control a myriad of innate social behaviors and acutely regulate hormone levels. Responses to pheromones are highly robust, reproducible, and stereotyped and likely involve developmentally predetermined neural circuits. Here, I review several facets of pheromone transduction in mammals, including (a) chemosensory receptors and signaling components of the main olfactory epithelium and vomeronasal organ involved in pheromone detection; (b) pheromone-activated neural circuits subject to sex-specific and state-dependent modulation; and (c) the striking chemical diversity of mammalian pheromones, which range from small, volatile molecules and sulfated steroids to large families of proteins. Finally, I review (d ) molecular mechanisms underlying various behavioral and endocrine responses, including modulation of puberty and estrous; control of reproduction, aggression, suckling, and parental behaviors; individual recognition; and distinguishing of own species from predators, competitors, and prey. Deconstruction of pheromone transduction mechanisms provides a critical foundation for understanding how odor response pathways generate instinctive behaviors. PMID:23988175

  1. Requirement for the Mitochondrial Pyruvate Carrier in Mammalian Development Revealed by a Hypomorphic Allelic Series

    PubMed Central

    Bowman, Caitlyn E.; Hartung, Thomas

    2016-01-01

    Glucose and oxygen are two of the most important molecules transferred from mother to fetus during eutherian pregnancy, and the metabolic fates of these nutrients converge at the transport and metabolism of pyruvate in mitochondria. Pyruvate enters the mitochondrial matrix through the mitochondrial pyruvate carrier (MPC), a complex in the inner mitochondrial membrane that consists of two essential components, MPC1 and MPC2. Here, we define the requirement for mitochondrial pyruvate metabolism during development with a progressive allelic series of Mpc1 deficiency in mouse. Mpc1 deletion was homozygous lethal in midgestation, but Mpc1 hypomorphs and tissue-specific deletion of Mpc1 presented as early perinatal lethality. The allelic series demonstrated that graded suppression of MPC resulted in dose-dependent metabolic and transcriptional changes. Steady-state metabolomics analysis of brain and liver from Mpc1 hypomorphic embryos identified compensatory changes in amino acid and lipid metabolism. Flux assays in Mpc1-deficient embryonic fibroblasts also reflected these changes, including a dramatic increase in mitochondrial alanine utilization. The mitochondrial alanine transaminase GPT2 was found to be necessary and sufficient for increased alanine flux upon MPC inhibition. These data show that impaired mitochondrial pyruvate transport results in biosynthetic deficiencies that can be mitigated in part by alternative anaplerotic substrates in utero. PMID:27215380

  2. Early childhood development in deprived urban settlements.

    PubMed

    Nair, M K C; Radhakrishnan, S Rekha

    2004-03-01

    Poverty, the root cause of the existence of slums or settlement colonies in urban areas has a great impact on almost all aspects of life of the urban poor, especially the all-round development of children. Examples from countries, across the globe provide evidence of improved early child development, made possible through integrated slum improvement programs, are few in numbers. The observed 2.5% prevalence of developmental delay in the less than 2 year olds of deprived urban settlements, the presence of risk factors for developmental delay like low birth weight, birth asphyxia, coupled with poor environment of home and alternate child care services, highlights the need for simple cost effective community model for promoting early child development. This review on early child development focuses on the developmental status of children in the deprived urban settlements, who are yet to be on the priority list of Governments and international agencies working for the welfare of children, the contributory nature-nurture factors and replicable working models like infant stimulation, early detection of developmental delay in infancy itself, developmental screening of toddlers, skill assessment for preschool children, school readiness programs, identification of mental sub-normality and primary education enhancement program for primary school children. Further, the review probes feasible intervention strategies through community owned early child care and development facilities, utilizing existing programs like ICDS, Urban Basic Services and by initiating services like Development Friendly Well Baby Clinics, Community Extension services, Child Development Referral Units at district hospitals and involving trained manpower like anganwadi/creche workers, public health nurses and developmental therapists. With the decentralization process the local self-government at municipalities and city corporations are financially equipped to be the prime movers to initiate, monitor and

  3. Early Brain Development Research Review and Update

    ERIC Educational Resources Information Center

    Schiller, Pam

    2010-01-01

    Thanks to imaging technology used in neurobiology, people have access to useful and critical information regarding the development of the human brain. This information allows them to become much more effective in helping children in their early development. In fact, when people base their practices on the findings from medical science research,…

  4. Gene-Chemical Interactions in the Developing Mammalian Nervous System: Effects on Proliferation, Neurogenesis and Differentiation

    PubMed Central

    Fox, Donald A.; Opanashuk, Lisa; Zharkovsky, Aleksander; Weiss, Bernie

    2010-01-01

    regulates xenobiotic metabolizing enzymes and growth factors, increased granule cell formation and apoptosis in the developing mouse cerebellum. Alex Zharkovsky described how postnatal early postnatal lead exposure decreased cell proliferation, neurogenesis and gene expression in the dentate gyrus of the adult hippocampus and its resultant behavioral effects. Bernard Weiss illustrated how environmental endocrine disruptors produced age- and gender-dependent alterations in synaptogenesis and cognitive behavior. PMID:20381523

  5. Early executive function predicts reasoning development.

    PubMed

    Richland, Lindsey E; Burchinal, Margaret R

    2013-01-01

    Analogical reasoning is a core cognitive skill that distinguishes humans from all other species and contributes to general fluid intelligence, creativity, and adaptive learning capacities. Yet its origins are not well understood. In the study reported here, we analyzed large-scale longitudinal data from the Study of Early Child Care and Youth Development to test predictors of growth in analogical-reasoning skill from third grade to adolescence. Our results suggest an integrative resolution to the theoretical debate regarding contributory factors arising from smaller-scale, cross-sectional experiments on analogy development. Children with greater executive-function skills (both composite and inhibitory control) and vocabulary knowledge in early elementary school displayed higher scores on a verbal analogies task at age 15 years, even after adjusting for key covariates. We posit that knowledge is a prerequisite to analogy performance, but strong executive-functioning resources during early childhood are related to long-term gains in fundamental reasoning skills.

  6. Bioecological Theory, Early Child Development and the Validation of the Population-Level Early Development Instrument

    ERIC Educational Resources Information Center

    Guhn, Martin; Goelman, Hillel

    2011-01-01

    The Early Development Instrument (EDI; Janus and Offord in "Canadian Journal of Behavioural Science" 39:1-22, 2007) project is a Canadian population-level, longitudinal research project, in which teacher ratings of Kindergarten children's early development and wellbeing are linked to health and academic achievement variables at the…

  7. Early Phonological Development: Creating an Assessment Test

    ERIC Educational Resources Information Center

    Stoel-Gammon, Carol; Williams, A. Lynn

    2013-01-01

    This paper describes a new protocol for assessing the phonological systems of two-year-olds with typical development and older children with delays in vocabulary acquisition. The test (Profiles of Early Expressive Phonological Skills ("PEEPS"), Williams & Stoel-Gammon, in preparation) differs from currently available assessments in…

  8. Early Intervention, Maternal Development and Children's Play.

    ERIC Educational Resources Information Center

    Slaughter, Diana T.

    The purposes of this longitudinal study of early intervention with 83 black mother-child dyads were (a) to test the thesis that sociocultural transmission influences childhood development in educationally significant ways, and (b) to describe the process through which such transmission can occur. Two social intervention programs were contrasted;…

  9. The Early Years: Development, Learning and Teaching.

    ERIC Educational Resources Information Center

    Boulton-Lewis, Gillian, Ed.; Catherwood, Di, Ed.

    Designed for teachers, students, caregivers, and health professionals who work with children from birth to age 8, this book provides a review of recent research and theories of development and learning in the early childhood years, with an emphasis on implications for effective teaching. Where appropriate, the book takes an Australian perspective,…

  10. EARLY CRANIOFACIAL DEVELOPMENT: LIFE AMONG THE SIGNALS

    EPA Science Inventory

    Early Craniofacial Development: Life Among the Signals. Sid Hunter and Keith Ward. Reproductive Toxicology Division, NHEERL, US EPA, RTP, NC, 27711

    Haloacetic acids (HAA) are chemicals formed during drinking water disinfection and present in finished tap water. Exposure o...

  11. Discovery of a Novel Prolactin in Non-Mammalian Vertebrates: Evolutionary Perspectives and Its Involvement in Teleost Retina Development

    PubMed Central

    Huang, Xigui; Hui, Michelle N. Y.; Liu, Yun; Yuen, Don S. H.; Zhang, Yong; Chan, Wood Yee; Lin, Hao Ran; Cheng, Shuk Han; Cheng, Christopher H. K.

    2009-01-01

    Background The three pituitary hormones, viz. prolactin (PRL), growth hormone (GH) and somatolactin (SL), together with the mammalian placental lactogen (PL), constitute a gene family of hormones with similar gene structure and encoded protein sequences. These hormones are believed to have evolved from a common ancestral gene through several rounds of gene duplication and subsequent divergence. Principal Findings In this study, we have identified a new PRL-like gene in non-mammalian vertebrates through bioinformatics and molecular cloning means. Phylogenetic analyses showed that this novel protein is homologous to the previously identified PRL. A receptor transactivation assay further showed that this novel protein could bind to PRL receptor to trigger the downstream post-receptor event, indicating that it is biologically active. In view of its close phylogenetic relationship with PRL and also its ability to activate PRL receptor, we name it as PRL2 and the previously identified PRL as PRL1. All the newly discovered PRL2 sequences possess three conserved disulfide linkages with the exception of the shark PRL2 which has only two. In sharp contrast to the classical PRL1 which is predominantly expressed in the pituitary, PRL2 was found to be mainly expressed in the eye and brain of the zebrafish but not in the pituitary. A largely reduced inner nuclear layer of the retina was observed after morpholino knockdown of zebrafish PRL2, indicating its role on retina development in teleost. Significance The discovery of this novel PRL has revitalized our understanding on the evolution of the GH/PRL/SL/PL gene family. Its unique expression and functions in the zebrafish eye also provide a new avenue of research on the neuroendocrine control of retina development in vertebrates. PMID:19584915

  12. Toward Understanding the Mammalian Zygoma: Insights From Comparative Anatomy, Growth and Development, and Morphometric Analysis.

    PubMed

    Márquez, Samuel; Pagano, Anthony S; Schwartz, Jeffrey H; Curtis, Abigail; Delman, Bradley N; Lawson, William; Laitman, Jeffrey T

    2017-01-01

    The zygoma, or jugum, is a cranial element that was present in Mesozoic tetrapods, well before the appearance of mammals. Although as an entity the zygoma is a primitive retention among mammals, it has assumed myriad configurations as this group diversified. As the zygoma is located at the intersection of the visual, respiratory, and masticatory apparatuses, it is potentially of great importance in systematic, phylogenetic, and functional studies focused on this region. For example, the facial component of the zygoma and its contribution to a postorbital bar (POB) appear to be relevant to the systematics of a number of mammalian subclades, and the formation of a bony postorbital septum (POS) that separates the orbit from the infratemporal fossa is unique to, and thus potentially phylogenetically significant for uniting anthropoid primates, while the zygoma itself appears to serve to resist tension and bending forces during mastication. In order to better understand the zygoma in the context of its contributions to the circumorbital region, we documented its morphological expression in specimens representing 10 orders of mammals. Since the presence of a POB and of a POS has long been used to justify uniting extant primates and anthropoid primates as respective clades, and because postorbital closure (POC) is morphologically more complex than a POB, we provide detail necessary to address these claims. Our taxically broad overview also allowed us to provide for the first time definitions of configurations that can be applied to future studies. Using a different, but also taxically broad sample of mammals, and of primates in particular, we performed two geometric morphometric analyses that were geared toward testing long-held interpretations of the functional role of the zygoma, especially with regard to mastication and in the context of orbital frontation (to which the zygoma contributes). Further, overall, zygomatic morphology tends not to scale with allometry

  13. Breastfeeding, parenting, and early cognitive development.

    PubMed

    Gibbs, Benjamin G; Forste, Renata

    2014-03-01

    To explain why breastfeeding is associated with children's cognitive development. By using a nationally representative longitudinal survey of early childhood (N = 7500), we examined how breastfeeding practices, the early introduction of solid foods, and putting an infant to bed with a bottle were associated with cognitive development across early childhood. We also explored whether this link can be explained by parenting behaviors and maternal education. There is a positive relationship between predominant breastfeeding for 3 months or more and child reading skills, but this link is the result of cognitively supportive parenting behaviors and greater levels of education among women who predominantly breastfed. We found little-to-no relationship between infant feeding practices and the cognitive development of children with less-educated mothers. Instead, reading to a child every day and being sensitive to a child's development were significant predictors of math and reading readiness outcomes. Although breastfeeding has important benefits in other settings, the encouragement of breastfeeding to promote school readiness does not appear to be a key intervention point. Promoting parenting behaviors that improve child cognitive development may be a more effective and direct strategy for practitioners to adopt, especially for disadvantaged children. Copyright © 2014 Mosby, Inc. All rights reserved.

  14. Nurturing care: promoting early childhood development.

    PubMed

    Britto, Pia R; Lye, Stephen J; Proulx, Kerrie; Yousafzai, Aisha K; Matthews, Stephen G; Vaivada, Tyler; Perez-Escamilla, Rafael; Rao, Nirmala; Ip, Patrick; Fernald, Lia C H; MacMillan, Harriet; Hanson, Mark; Wachs, Theodore D; Yao, Haogen; Yoshikawa, Hirokazu; Cerezo, Adrian; Leckman, James F; Bhutta, Zulfiqar A

    2017-01-07

    The UN Sustainable Development Goals provide a historic opportunity to implement interventions, at scale, to promote early childhood development. Although the evidence base for the importance of early childhood development has grown, the research is distributed across sectors, populations, and settings, with diversity noted in both scope and focus. We provide a comprehensive updated analysis of early childhood development interventions across the five sectors of health, nutrition, education, child protection, and social protection. Our review concludes that to make interventions successful, smart, and sustainable, they need to be implemented as multi-sectoral intervention packages anchored in nurturing care. The recommendations emphasise that intervention packages should be applied at developmentally appropriate times during the life course, target multiple risks, and build on existing delivery platforms for feasibility of scale-up. While interventions will continue to improve with the growth of developmental science, the evidence now strongly suggests that parents, caregivers, and families need to be supported in providing nurturing care and protection in order for young children to achieve their developmental potential. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Developmental insights from early mammalian embryos and core signaling pathways that influence human pluripotent cell growth and differentiation.

    PubMed

    Chen, Kevin G; Mallon, Barbara S; Johnson, Kory R; Hamilton, Rebecca S; McKay, Ronald D G; Robey, Pamela G

    2014-05-01

    Human pluripotent stem cells (hPSCs) have two potentially attractive applications: cell replacement-based therapies and drug discovery. Both require the efficient generation of large quantities of clinical-grade stem cells that are free from harmful genomic alterations. The currently employed colony-type culture methods often result in low cell yields, unavoidably heterogeneous cell populations, and substantial chromosomal abnormalities. Here, we shed light on the structural relationship between hPSC colonies/embryoid bodies and early-stage embryos in order to optimize current culture methods based on the insights from developmental biology. We further highlight core signaling pathways that underlie multiple epithelial-to-mesenchymal transitions (EMTs), cellular heterogeneity, and chromosomal instability in hPSCs. We also analyze emerging methods such as non-colony type monolayer (NCM) and suspension culture, which provide alternative growth models for hPSC expansion and differentiation. Furthermore, based on the influence of cell-cell interactions and signaling pathways, we propose concepts, strategies, and solutions for production of clinical-grade hPSCs, stem cell precursors, and miniorganoids, which are pivotal steps needed for future clinical applications. Published by Elsevier B.V.

  16. Early childhood development: putting knowledge into action.

    PubMed

    2000-11-01

    As part of its continuing mission to serve trustees and staff of health foundations and corporate giving programs, Grantmakers In Health (GIH) convened a select group of grantmakers and national experts who have made a major commitment to improve the health and well being of young children. The roundtable explored the latest research examining early childhood development, as well as public and private programs serving families with young children. The discussion ultimately centered upon the importance of grantmaker involvement to improve early childhood development, including the services delivered to young children and their families, training for professionals, and continued research and evaluation. This report brings together key points from the day's discussion with factual information on demographic, health and human services, and public policy trends drawn from a background paper prepared for the meeting. When available, recent findings, facts, and figures have been incorporated.

  17. Dual effects of fluoxetine on mouse early embryonic development

    SciTech Connect

    Kim, Chang-Woon; Department of Obstetrics and Gynecology, Samsung Changwon Hospital, Sungkyunkwan University, Changwon 630-723; Choe, Changyong

    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 fluoxetinemore » (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

  18. Expanding the test set: Chemicals with potential to disrupt mammalian brain development

    EPA Science Inventory

    High-throughput test methods including molecular, cellular, and alternative species-based assays that examine critical events of normal brain development are being developed for detection of developmental neurotoxcants. As new assays are developed, a "training set' of chemicals i...

  19. QCD development in the early universe

    SciTech Connect

    Gromov, N. A., E-mail: gromov@dm.komisc.ru

    The high-energy limit of Quantum Chromodynamics is generated by the contraction of its gauge groups. Contraction parameters are taken identical with those of the Electroweak Model and tend to zero when energy increases. At the infinite energy limit all quarks lose masses and have only one color degree of freedom. The limit model represents the development of Quantum Chromodynamics in the early Universe from the Big Bang up to the end of several milliseconds.

  20. Early colonial health developments in Mauritius.

    PubMed

    Parahoo, K A

    1986-01-01

    The historical development of Mauritius and in particular the early developments in health care are crucial to an understanding of the contemporary health system. The introduction of major epidemic diseases through the movements of French soldiers to and from India and the immigration of indentured laborers from India account for the high mortality and morbidity rates in the 18th and 19th centuries and later. The colonial economy created and fortified the dependence on a single cash crop and on imported food. It also contributed toward the impoverization of large sections of the Mauritian population. The colonial era is also responsible for initiating a three tier system of health care.

  1. Advances on microRNA in regulating mammalian skeletal muscle development.

    PubMed

    Li, Xin-Yun; Fu, Liang-Liang; Cheng, Hui-Jun; Zhao, Shu-Hong

    2017-11-20

    MicroRNA (miRNA) is a class of short non-coding RNA, which is about 22 bp in length. In mammals, miRNA exerts its funtion through binding with the 3°-UTR region of target genes and inhibiting their translation. Skeletal muscle development is a complex event, including: proliferation, migration and differentiation of skeletal muscle stem cells; proliferation, differentiation and fusion of myocytes; as well as hypertrophy, energy metabolism and conversion of muscle fiber types. The miRNA plays important roles in all processes of skeletal muscle development through targeting the key factors of different stages. Herein we summarize the miRNA related to muscle development, providing a better understanding of the skeletal muscle development.

  2. Computer simulation analysis of normal and abnormal development of the mammalian diaphragm

    PubMed Central

    Fisher, Jason C; Bodenstein, Lawrence

    2006-01-01

    Background Congenital diaphragmatic hernia (CDH) is a birth defect with significant morbidity and mortality. Knowledge of diaphragm morphogenesis and the aberrations leading to CDH is limited. Although classical embryologists described the diaphragm as arising from the septum transversum, pleuroperitoneal folds (PPF), esophageal mesentery and body wall, animal studies suggest that the PPF is the major, if not sole, contributor to the muscular diaphragm. Recently, a posterior defect in the PPF has been identified when the teratogen nitrofen is used to induce CDH in fetal rodents. We describe use of a cell-based computer modeling system (Nudge++™) to study diaphragm morphogenesis. Methods and results Key diaphragmatic structures were digitized from transverse serial sections of paraffin-embedded mouse embryos at embryonic days 11.5 and 13. Structure boundaries and simulated cells were combined in the Nudge++™ software. Model cells were assigned putative behavioral programs, and these programs were progressively modified to produce a diaphragm consistent with the observed anatomy in rodents. Homology between our model and recent anatomical observations occurred under the following simulation conditions: (1) cell mitoses are restricted to the edge of growing tissue; (2) cells near the chest wall remain mitotically active; (3) mitotically active non-edge cells migrate toward the chest wall; and (4) movement direction depends on clonal differentiation between anterior and posterior PPF cells. Conclusion With the PPF as the sole source of mitotic cells, an early defect in the PPF evolves into a posteromedial diaphragm defect, similar to that of the rodent nitrofen CDH model. A posterolateral defect, as occurs in human CDH, would be more readily recreated by invoking other cellular contributions. Our results suggest that recent reports of PPF-dominated diaphragm morphogenesis in the rodent may not be strictly applicable to man. The ability to recreate a CDH defect

  3. Computer simulation analysis of normal and abnormal development of the mammalian diaphragm.

    PubMed

    Fisher, Jason C; Bodenstein, Lawrence

    2006-02-17

    Congenital diaphragmatic hernia (CDH) is a birth defect with significant morbidity and mortality. Knowledge of diaphragm morphogenesis and the aberrations leading to CDH is limited. Although classical embryologists described the diaphragm as arising from the septum transversum, pleuroperitoneal folds (PPF), esophageal mesentery and body wall, animal studies suggest that the PPF is the major, if not sole, contributor to the muscular diaphragm. Recently, a posterior defect in the PPF has been identified when the teratogen nitrofen is used to induce CDH in fetal rodents. We describe use of a cell-based computer modeling system (Nudge++) to study diaphragm morphogenesis. Key diaphragmatic structures were digitized from transverse serial sections of paraffin-embedded mouse embryos at embryonic days 11.5 and 13. Structure boundaries and simulated cells were combined in the Nudge++ software. Model cells were assigned putative behavioral programs, and these programs were progressively modified to produce a diaphragm consistent with the observed anatomy in rodents. Homology between our model and recent anatomical observations occurred under the following simulation conditions: (1) cell mitoses are restricted to the edge of growing tissue; (2) cells near the chest wall remain mitotically active; (3) mitotically active non-edge cells migrate toward the chest wall; and (4) movement direction depends on clonal differentiation between anterior and posterior PPF cells. With the PPF as the sole source of mitotic cells, an early defect in the PPF evolves into a posteromedial diaphragm defect, similar to that of the rodent nitrofen CDH model. A posterolateral defect, as occurs in human CDH, would be more readily recreated by invoking other cellular contributions. Our results suggest that recent reports of PPF-dominated diaphragm morphogenesis in the rodent may not be strictly applicable to man. The ability to recreate a CDH defect using a combination of experimental data and

  4. The biology of mammalian parenting and its effect on offspring social development.

    PubMed

    Rilling, James K; Young, Larry J

    2014-08-15

    Parents know the transformative nature of having and caring for a child. Among many mammals, giving birth leads from an aversion to infant stimuli to irresistible attraction. Here, we review the biological mechanisms governing this shift in parental motivation in mammals. Estrogen and progesterone prepare the uterus for embryo implantation and placental development. Prolactin stimulates milk production, whereas oxytocin initiates labor and triggers milk ejection during nursing. These same molecules, interacting with dopamine, also activate specific neural pathways to motivate parents to nurture, bond with, and protect their offspring. Parenting in turn shapes the neural development of the infant social brain. Recent work suggests that many of the principles governing parental behavior and its effect on infant development are conserved from rodent to humans. Copyright © 2014, American Association for the Advancement of Science.

  5. Gravity in mammalian organ development: differentiation of cultured lung and pancreas rudiments during spaceflight

    NASA Technical Reports Server (NTRS)

    Spooner, B. S.; Hardman, P.; Paulsen, A.

    1994-01-01

    Organ culture of embryonic mouse lung and pancreas rudiments has been used to investigate development and differentiation, and to assess the effects of microgravity on culture differentiation, during orbital spaceflight of the shuttle Endeavour (mission STS-54). Lung rudiments continue to grow and branch during spaceflight, an initial result that should allow future detailed study of lung morphogenesis in microgravity. Cultured embryonic pancreas undergoes characteristic exocrine acinar tissue and endocrine islet tissue differentiation during spaceflight, and in ground controls. The rudiments developing in the microgravity environment of spaceflight appear to grow larger than their ground counterparts, and they may have differentiated more rapidly than controls, as judged by exocrine zymogen granule presence.

  6. Chemical energetics of force development, force maintenance, and relaxation in mammalian smooth muscle

    PubMed Central

    1980-01-01

    High-energy phosphate utilization (delta approximately P) associated with force development, force maintenance, and relaxation has been determined during single isometric tetani in the rabbit taenia coli. ATP resynthesis from glycolysis and respiration was stopped without deleterious effects on the muscle. At 18 degrees C and a muscle length of 95% l0, the resting rate of energy utilization is 1.8 +/- 0.2 nmol/g . s-1, or 0.85 +/- 0.2 mmol approximately P/mol of total creatine (Ct) . s-1, where Ct = 2.7 mumol/g wet wt. During the initial 25 s of stimulation when force is developed, the average rate of delta approximately P was -8.2 +/- 0.8 mmol/mol Ct . s-1, some four times greater than during the subsequent 35 s of force maintenance, when the rate was -2.0 +/- 0.6 mmol approximately P/mol Ct . s-1. The energy cost of force redevelopment (0 to 95% P0) after a quick release from the peak of a tetanus is very low compared with the initial force development. Therefore, the high rate of energy utilization during force development is not due only to internal work done against the series elasticity nor to any high rate of cross-bridge cycling inherently associated with force development. The high economy of force maintenance compared with other muscle types is undoubtedly due to a slower cross-bridge cycle time. The energy utilization during 45 s of relaxation was not statistically significant, and integral of Pdt/delta approximately P was higher during relaxation than during force maintenance in the stimulated muscle. PMID:6969290

  7. Pharmacogenomics in early-phase clinical development

    PubMed Central

    Burt, Tal; Dhillon, Savita

    2015-01-01

    Pharmacogenomics (PGx) offers the promise of utilizing genetic fingerprints to predict individual responses to drugs in terms of safety, efficacy and pharmacokinetics. Early-phase clinical trial PGx applications can identify human genome variations that are meaningful to study design, selection of participants, allocation of resources and clinical research ethics. Results can inform later-phase study design and pipeline developmental decisions. Nevertheless, our review of the clinicaltrials.gov database demonstrates that PGx is rarely used by drug developers. Of the total 323 trials that included PGx as an outcome, 80% have been conducted by academic institutions after initial regulatory approval. Barriers for the application of PGx are discussed. We propose a framework for the role of PGx in early-phase drug development and recommend PGx be universally considered in study design, result interpretation and hypothesis generation for later-phase studies, but PGx results from underpowered studies should not be used by themselves to terminate drug-development programs. PMID:23837482

  8. The developing hypopharyngeal microbiota in early life.

    PubMed

    Mortensen, Martin Steen; Brejnrod, Asker Daniel; Roggenbuck, Michael; Abu Al-Soud, Waleed; Balle, Christina; Krogfelt, Karen Angeliki; Stokholm, Jakob; Thorsen, Jonathan; Waage, Johannes; Rasmussen, Morten Arendt; Bisgaard, Hans; Sørensen, Søren Johannes

    2016-12-30

    The airways of healthy humans harbor a distinct microbial community. Perturbations in the microbial community have been associated with disease, yet little is known about the formation and development of a healthy airway microbiota in early life. Our goal was to understand the establishment of the airway microbiota within the first 3 months of life. We investigated the hypopharyngeal microbiota in the unselected COPSAC 2010 cohort of 700 infants, using 16S rRNA gene sequencing of hypopharyngeal aspirates from 1 week, 1 month, and 3 months of age. Our analysis shows that majority of the hypopharyngeal microbiota of healthy infants belong to each individual's core microbiota and we demonstrate five distinct community pneumotypes. Four of these pneumotypes are dominated by the genera Staphylococcus, Streptococcus, Moraxella, and Corynebacterium, respectively. Furthermore, we show temporal pneumotype changes suggesting a rapid development towards maturation of the hypopharyngeal microbiota and a significant effect from older siblings. Despite an overall common trajectory towards maturation, individual infants' microbiota are more similar to their own, than to others, over time. Our findings demonstrate a consolidation of the population of indigenous bacteria in healthy airways and indicate distinct trajectories in the early development of the hypopharyngeal microbiota.

  9. Mammalian meat allergy following a tick bite: a case report.

    PubMed

    Jackson, W Landon

    2018-02-01

    The alpha-gal allergy is an emerging IgE-mediated reaction against the galactose-alpha-1,3-galactose carbohydrate found in mammalian meats. Patients with this condition will develop anaphylactic symptoms 3-6 h after the ingestion of mammalian meat food products such as beef, pork or lamb. The prevalence of this allergy is drastically increasing and severe reactions including anaphylactic shock have been reported, yet many patients experience symptoms for years before a diagnosis is made. We describe the presentation, diagnosis and management of a patient with the alpha-gal allergy in attempt to improve early recognition and management of patients with this condition.

  10. A fusion-protein approach enabling mammalian cell production of tumor targeting protein domains for therapeutic development.

    PubMed

    Hu, Jia; Chen, Xiang; Zhang, Xuhua; Yuan, Xiaopeng; Yang, Mingjuan; Dai, Hui; Yang, Wei; Zhou, Qinghua; Wen, Weihong; Wang, Qirui; Qin, Weijun; Zhao, Aizhi

    2018-05-01

    A single chain Fv fragment (scFv) is a fusion of the variable regions of heavy (V H ) and light (V L ) chains of immunoglobulins. They are important elements of chimeric antigen receptors for cancer therapy. We sought to produce a panel of 16 extracellular protein domains of tumor markers for use in scFv yeast library screenings. A series of vectors comprising various combinations of expression elements was made, but expression was unpredictable and more than half of the protein domains could not be produced using any of the constructs. Here we describe a novel fusion expression system based on mouse TEM7 (tumor endothelial marker 7), which could facilitate protein expression. With this approach we could produce all but one of the tumor marker domains that could not otherwise be expressed. In addition, we demonstrated that the tumor associated antigen hFZD10 produced as a fusion protein with mTEM7 could be used to enrich scFv antibodies from a yeast display library. Collectively our study demonstrates the potential of specific fusion proteins based on mTEM7 in enabling mammalian cell production of tumor targeting protein domains for therapeutic development. © 2018 The Protein Society.

  11. Observations on the elimination of polyneuronal innervation in developing mammalian skeletal muscle.

    PubMed Central

    O'Brien, R A; Ostberg, A J; Vrbová, G

    1978-01-01

    1. The mechanism responsible for the elimination of polyneuronal innervation in developing rat soleus muscles was studied electrophysiologically and histologically. 2. Initially all the axons contacting a single end-plate have simple bulbous terminals. As elimination proceeds one axon develops terminal branches while the other terminals remain bulbous and may be seen in contact with, or a short distance away from, the end-plate. It is suggested that the branched terminal remains in contact with the muscle fibre while the other terminals withdraw. 3. At a time when polyneuronal innervation can no longer be detected electrophysiologically, the histological technique still shows the presence of end-plates contacted by more than one nerve terminal. 4. The effect of activity on the disappearance of polyneuronal innervation was examined. Activity was increased by electrical stimulation of the right sciatic nerve. This procedure also produced reflex activity in the contralateral limb. In both cases polyneuronal innervation was eliminated more rapidly in the active muscles. 5. The finding that proteolytic enzymes are released from muscles treated with acetylcholine (ACh), and the observation of the more rapid elimination of supernumerary terminals at the end-plates of active muscles, lead to the suggestion that superfluous nerve-muscle contacts are removed by the proteolytic enzymes in response to neuromuscular activity. The selective stabilization of only one of the terminals is discussed in the light of these results. Images Plate 1 Plate 2 PMID:722562

  12. Expression and function of FGF10 in mammalian inner ear development

    NASA Technical Reports Server (NTRS)

    Pauley, Sarah; Wright, Tracy J.; Pirvola, Ulla; Ornitz, David; Beisel, Kirk; Fritzsch, Bernd

    2003-01-01

    We have investigated the expression of FGF10 during ear development and the effect of an FGF10 null mutation on ear development. Our in situ hybridization data reveal expression of FGF10 in all three canal crista sensory epithelia and the cochlea anlage as well as all sensory neurons at embryonic day 11.5 (E11.5). Older embryos (E18.5) displayed strong graded expression in all sensory epithelia. FGF10 null mutants show complete agenesis of the posterior canal crista and the posterior canal. The posterior canal sensory neurons form initially and project rather normally by E11.5, but they disappear within 2 days. FGF10 null mutants have no posterior canal system at E18.5. In addition, these mutants have deformations of the anterior and horizontal cristae, reduced formation of the anterior and horizontal canals, as well as altered position of the remaining sensory epithelia with respect to the utricle. Hair cells form but some have defects in their cilia formation. No defects were detected in the organ of Corti at the cellular level. Together these data suggest that FGF10 plays a major role in ear morphogenesis. Most of these data are consistent with earlier findings on a null mutation in FGFR2b, one of FGF10's main receptors. Copyright 2003 Wiley-Liss, Inc.

  13. A mechanistic link between gene regulation and genome architecture in mammalian development.

    PubMed

    Bonora, Giancarlo; Plath, Kathrin; Denholtz, Matthew

    2014-08-01

    The organization of chromatin within the nucleus and the regulation of transcription are tightly linked. Recently, mechanisms underlying this relationship have been uncovered. By defining the organizational hierarchy of the genome, determining changes in chromatin organization associated with changes in cell identity, and describing chromatin organization within the context of linear genomic features (such as chromatin modifications and transcription factor binding) and architectural proteins (including Cohesin, CTCF, and Mediator), a new paradigm in genome biology was established wherein genomes are organized around gene regulatory factors that govern cell identity. As such, chromatin organization plays a central role in establishing and maintaining cell state during development, with gene regulation and genome organization being mutually dependent effectors of cell identity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Development of an electro-responsive platform for the controlled transfection of mammalian cells

    NASA Astrophysics Data System (ADS)

    Hook, Andrew L.; Thissen, Helmut W.; Hayes, Jason P.; Voelcker, Nicolas H.

    2005-02-01

    The recent development of living microarrays as novel tools for the analysis of gene expression in an in-situ environment promises to unravel gene function within living organisms. In order to significantly enhance microarray performance, we are working towards electro-responsive DNA transfection chips. This study focuses on the control of DNA adsorption and desorption by appropriate surface modification of highly doped p++ silicon. Silicon was modified by plasma polymerisation of allylamine (ALAPP), a non-toxic surface that sustains cell growth. Subsequent high surface density grafting of poly(ethylene oxide) formed a layer resistant to biomolecule adsorption and cell attachment. Spatially controlled excimer laser ablation of the surface produced micron resolution patterns of re-exposed plasma polymer whilst the rest of the surface remained non-fouling. We observed electro-stimulated preferential adsorption of DNA to the ALAPP surface and subsequent desorption by the application of a negative bias. Cell culture experiments with HEK 293 cells demonstrated efficient and controlled transfection of cells using the expression of green fluorescent protein as a reporter. Thus, these chemically patterned surfaces are promising platforms for use as living microarrays.

  15. Migrating Interneurons Secrete Fractalkine to Promote Oligodendrocyte Formation in the Developing Mammalian Brain.

    PubMed

    Voronova, Anastassia; Yuzwa, Scott A; Wang, Beatrix S; Zahr, Siraj; Syal, Charvi; Wang, Jing; Kaplan, David R; Miller, Freda D

    2017-05-03

    During development, newborn interneurons migrate throughout the embryonic brain. Here, we provide evidence that these interneurons act in a paracrine fashion to regulate developmental oligodendrocyte formation. Specifically, we show that medial ganglionic eminence (MGE) interneurons secrete factors that promote genesis of oligodendrocytes from glially biased cortical precursors in culture. Moreover, when MGE interneurons are genetically ablated in vivo prior to their migration, this causes a deficit in cortical oligodendrogenesis. Modeling of the interneuron-precursor paracrine interaction using transcriptome data identifies the cytokine fractalkine as responsible for the pro-oligodendrocyte effect in culture. This paracrine interaction is important in vivo, since knockdown of the fractalkine receptor CX3CR1 in embryonic cortical precursors, or constitutive knockout of CX3CR1, causes decreased numbers of oligodendrocyte progenitor cells (OPCs) and oligodendrocytes in the postnatal cortex. Thus, in addition to their role in regulating neuronal excitability, interneurons act in a paracrine fashion to promote the developmental genesis of oligodendrocytes. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Development, reliability and validation of an infant mammalian penetration-aspiration scale

    PubMed Central

    Holman, Shaina Devi; Campbell-Malone, Regina; Ding, Peng; Gierbolini-Norat, Estela M.; Griffioen, Anne M.; Inokuchi, Haruhi; Lukasik, Stacey L.; German, Rebecca Z.

    2012-01-01

    A penetration-aspiration scale exists for assessing airway protection in adult videofluoroscopy and fiberoptic endoscopic swallowing studies, however no such scale exists for animal models. The aim of this study was threefold to 1) develop a Penetration-Aspiration Scale (PAS) for infant mammals, 2) test the scale’s intra- and inter-rater reliability, and 3) to validate the use of the scale for distinguishing between abnormal and normal animals. After discussion and reviewing many videos, the result was a 7-Point Infant Mammal PAS. Reliability was tested by having 5 judges score 90 swallows recorded with videofluoroscopy across two time points. In these videos, the frame rate was either 30 or 60 frames per second and the animals were either normal, had a unilateral superior laryngeal nerve (SLN) lesion, or had hard palate local anesthesia. The scale was validated by having one judge score videos of both normal and SLN lesioned pigs and testing the difference using a t-test. Raters had a high intra-rater (average kappa of 0.82, intraclass correlation coefficient (ICC)= 0.92) and high inter-rater reliability (average kappa of 0.68, ICC= 0.66). There was a significant difference in reliability for videos captured at 30 and 60 frames per second for scores of 3 and 7 (p<0.001). The scale was also validated for distinguishing between normal and abnormal pigs (p<0.001). Given the increasing number of animal studies using videofluoroscopy to study dysphagia, this scale provides a valid and reliable measure of airway protection during swallowing in infant pigs that will give these animal models increased translational significance. PMID:23129423

  17. Report of the NASA Mammalian Developmental Biology Working Group

    NASA Technical Reports Server (NTRS)

    Keefe, J. R.

    1985-01-01

    Development is considered to encompass all aspects of the mammalian life span from initial initial germ cell production through the complete life cycle to death of the organism. Thus, gamete production, fertilization, embryogenesis, implantation, fetogenesis, birth, peri- and postnatal maturation, and aging were all considered as stages of a development continuum relevant to problems of Space Biology. Deliberations thus far have been limited to stages of the development cycle from fertilization to early postnatal life. The deliberations are detailed.

  18. Early Literacy and Early Numeracy: The Value of Including Early Literacy Skills in the Prediction of Numeracy Development

    ERIC Educational Resources Information Center

    Purpura, David J.; Hume, Laura E.; Sims, Darcey M.; Lonigan, Cristopher J.

    2011-01-01

    The purpose of this study was to examine whether early literacy skills uniquely predict early numeracy skills development. During the first year of the study, 69 3- to 5-year-old preschoolers were assessed on the Preschool Early Numeracy Skills (PENS) test and the Test of Preschool Early Literacy Skills (TOPEL). Participants were assessed again a…

  19. XBtg2 is required for notochord differentiation during early Xenopus development.

    PubMed

    Sugimoto, Kaoru; Hayata, Tadayoshi; Asashima, Makoto

    2005-09-01

    The notochord is essential for normal vertebrate development, serving as both a structural support for the embryo and a signaling source for the patterning of adjacent tissues. Previous studies on the notochord have mostly focused on its formation and function in early organogenesis but gene regulation in the differentiation of notochord cells itself remains poorly defined. In the course of screening for genes expressed in developing notochord, we have isolated Xenopus homolog of Btg2 (XBtg2). The mammalian Btg2 genes, Btg2/PC3/TIS21, have been reported to have multiple functions in the regulation of cell proliferation and differentiation but their roles in early development are still unclear. Here we characterized XBtg2 in early Xenopus laevis embryogenesis with focus on notochord development. Translational inhibition of XBtg2 resulted in a shortened and bent axis phenotype and the abnormal structures in the notochord tissue, which did not undergo vacuolation. The XBtg2-depleted notochord cells expressed early notochord markers such as chordin and Xnot at the early tailbud stage, but failed to express differentiation markers of notochord such as Tor70 and 5-D-4 antigens in the later stages. These results suggest that XBtg2 is required for the differentiation of notochord cells such as the process of vacuolar formation after determination of notochord cell fate.

  20. Development of Life on Early Mars

    NASA Technical Reports Server (NTRS)

    Gibson, Everett K.; McKay, David S.; Thomas-Keprta, Kathie L.; Clemett, Simon J.; Wentworth, Susan J.

    2009-01-01

    Exploration of Mars has begun to unveil the history of the planet. Combinations of remote sensing, in situ compositional measurements and photographic observations have shown Mars had a dynamic and active geologic evolution. Mars geologic evolution encompassed conditions that were suitable for supporting life. A habitable planet must have water, carbon and energy sources along with a dynamic geologic past. Mars meets all of these requirements. The first 600 My of Martian history were ripe for life to develop because of the abundance of (i) Water- as shown by carved canyons and oceans or lakes with the early presence of near surface water shown by precipitated carbonates in ALH84001, well-dated at 3.9 Gy, (ii) Energy from the original accretional processes, a molten core which generated a strong magnetic field leaving a permanent record in the early crust, active volcanism continuing throughout Martian history, and continuing impact processes, (iii) Carbon, water and a likely thicker atmosphere from extensive volcanic outgassing (i.e. H20, CO2, CH4, CO, O2, N2, H2S, SO2, etc.) and (iv) crustal tectonics as revealed by faulting and possible plate movement reflected by the magnetic pattern in the crust [1]. The question arises: "Why would life not develop from these favorable conditions on Mars in its first 600 My?" During this period, environmental near-surface conditions on Mars were more favorable to life than at any later time. Standing bodies of water, precipitation and flowing surface water, and possibly abundant hydrothermal energy would favor the formation of early life. (Even if life developed elsewhere on Earth, Venus, or on other bodies-it was transported to Mars where surface conditions were suitable for life to evolve). The commonly stated requirement that life would need hundreds of millions of year to get started is only an assumption; we know of no evidence that requires such a long interval for the development of life, if the proper habitable

  1. How Early Hormones Shape Gender Development

    PubMed Central

    Berenbaum, Sheri A.; Beltz, Adriene M.

    2015-01-01

    Many important psychological characteristics show sex differences, and are influenced by sex hormones at different developmental periods. We focus on the role of sex hormones in early development, particularly the differential effects of prenatal androgens on aspects of gender development. Increasing evidence confirms that prenatal androgens have facilitative effects on male-typed activity interests and engagement (including child toy preferences and adult careers), and spatial abilities, but relatively minimal effects on gender identity. Recent emphasis has been directed to the psychological mechanisms underlying these effects (including sex differences in propulsive movement, and androgen effects on interest in people versus things), and neural substrates of androgen effects (including regional brain volumes, and neural responses to mental rotation, sexually arousing stimuli, emotion, and reward). Ongoing and planned work is focused on understanding the ways in which hormones act jointly with the social environment across time to produce varying trajectories of gender development, and clarifying mechanisms by which androgens affect behaviors. Such work will be facilitated by applying lessons from other species, and by expanding methodology. Understanding hormonal influences on gender development enhances knowledge of psychological development generally, and has important implications for basic and applied questions, including sex differences in psychopathology, women’s underrepresentation in science and math, and clinical care of individuals with variations in gender expression. PMID:26688827

  2. Development of an enzyme immunoassay for detection of antibodies against Coccidioides in dogs and other mammalian species.

    PubMed

    Chow, Nancy A; Lindsley, Mark D; McCotter, Orion Z; Kangiser, Dave; Wohrle, Ron D; Clifford, Wayne R; Yaglom, Hayley D; Adams, Laura E; Komatsu, Kenneth; Durkin, Michelle M; Baker, Rocky J; Shubitz, Lisa F; Derado, Gordana; Chiller, Tom M; Litvintseva, Anastasia P

    2017-01-01

    Coccidioides is a soil-dwelling fungus that causes coccidioidomycosis, a disease also known as Valley fever, which affects humans and a variety of animal species. Recent findings of Coccidioides in new, unexpected areas of the United States have demonstrated the need for a better understanding of its geographic distribution. Large serological studies on animals could provide important information on the geographic distribution of this pathogen. To facilitate such studies, we used protein A/G, a recombinant protein that binds IgG antibodies from a variety of mammalian species, to develop an enzyme immunoassay (EIA) that detects IgG antibodies against Coccidioides in a highly sensitive and high-throughput manner. We showed the potential of this assay to be adapted to multiple animal species by testing a collection of serum and/or plasma samples from dogs, mice, and humans with or without confirmed coccidioidomycosis. We then evaluated the performance of the assay in dogs, using sera from dogs residing in a highly endemic area, and found seropositivity rates significantly higher than those in dogs of non-endemic areas. We further evaluated the specificity of the assay in dogs infected with other fungal pathogens known to cross-react with Coccidioides. Finally, we used the assay to perform a cross-sectional serosurvey investigating dogs from Washington, a state in which infection with Coccidioides has recently been documented. In summary, we have developed a Coccidioides EIA for the detection of antibodies in canines that is more sensitive and has higher throughput than currently available methods, and by testing this assay in mice and humans, we have shown a proof of principle of its adaptability for other animal species.

  3. Development of an enzyme immunoassay for detection of antibodies against Coccidioides in dogs and other mammalian species

    PubMed Central

    Lindsley, Mark D.; McCotter, Orion Z.; Kangiser, Dave; Wohrle, Ron D.; Clifford, Wayne R.; Yaglom, Hayley D.; Adams, Laura E.; Komatsu, Kenneth; Durkin, Michelle M.; Baker, Rocky J.; Shubitz, Lisa F.; Derado, Gordana; Chiller, Tom M.; Litvintseva, Anastasia P.

    2017-01-01

    Coccidioides is a soil-dwelling fungus that causes coccidioidomycosis, a disease also known as Valley fever, which affects humans and a variety of animal species. Recent findings of Coccidioides in new, unexpected areas of the United States have demonstrated the need for a better understanding of its geographic distribution. Large serological studies on animals could provide important information on the geographic distribution of this pathogen. To facilitate such studies, we used protein A/G, a recombinant protein that binds IgG antibodies from a variety of mammalian species, to develop an enzyme immunoassay (EIA) that detects IgG antibodies against Coccidioides in a highly sensitive and high-throughput manner. We showed the potential of this assay to be adapted to multiple animal species by testing a collection of serum and/or plasma samples from dogs, mice, and humans with or without confirmed coccidioidomycosis. We then evaluated the performance of the assay in dogs, using sera from dogs residing in a highly endemic area, and found seropositivity rates significantly higher than those in dogs of non-endemic areas. We further evaluated the specificity of the assay in dogs infected with other fungal pathogens known to cross-react with Coccidioides. Finally, we used the assay to perform a cross-sectional serosurvey investigating dogs from Washington, a state in which infection with Coccidioides has recently been documented. In summary, we have developed a Coccidioides EIA for the detection of antibodies in canines that is more sensitive and has higher throughput than currently available methods, and by testing this assay in mice and humans, we have shown a proof of principle of its adaptability for other animal species. PMID:28380017

  4. The nematode Caenorhabditis elegans as a tool to predict chemical activity on mammalian development and identify mechanisms influencing toxicological outcome.

    PubMed

    Harlow, Philippa H; Perry, Simon J; Widdison, Stephanie; Daniels, Shannon; Bondo, Eddie; Lamberth, Clemens; Currie, Richard A; Flemming, Anthony J

    2016-03-18

    To determine whether a C. elegans bioassay could predict mammalian developmental activity, we selected diverse compounds known and known not to elicit such activity and measured their effect on C. elegans egg viability. 89% of compounds that reduced C. elegans egg viability also had mammalian developmental activity. Conversely only 25% of compounds found not to reduce egg viability in C. elegans were also inactive in mammals. We conclude that the C. elegans egg viability assay is an accurate positive predictor, but an inaccurate negative predictor, of mammalian developmental activity. We then evaluated C. elegans as a tool to identify mechanisms affecting toxicological outcomes among related compounds. The difference in developmental activity of structurally related fungicides in C. elegans correlated with their rate of metabolism. Knockdown of the cytochrome P450s cyp-35A3 and cyp-35A4 increased the toxicity to C. elegans of the least developmentally active compounds to the level of the most developmentally active. This indicated that these P450s were involved in the greater rate of metabolism of the less toxic of these compounds. We conclude that C. elegans based approaches can predict mammalian developmental activity and can yield plausible hypotheses for factors affecting the biological potency of compounds in mammals.

  5. Early Vascular Ageing - A Concept in Development.

    PubMed

    M Nilsson, Peter

    2015-04-01

    Cardiovascular disease (CVD) is a prevalent condition in the elderly, often associated with metabolic disturbance and type 2 diabetes. For a number of years, research dedicated to understand atherosclerosis dominated, and for many good reasons, this pathophysiological process being proximal to the CVD events. In recent years, research has been devoted to an earlier stage of vascular pathology named arteriosclerosis (arterial stiffness) and the new concept of early vascular ageing (EVA), developed by a group of mostly European researchers. This overview describes recent developments in research dedicated to EVA and new emerging aspects found in studies of families at high cardiovascular risk. There are new aspects related to genetics, telomere biology and the role of gut microbiota. However, there is still no unifying definition available of EVA and no direct treatment, but rather only recommendations for conventional cardiovascular risk factor control. New interventions are being developed - not only new antihypertensive drugs, but also new drugs for vascular protection - the selective angiotensin-II (AT2) agonist Compound 21 (C21). Human studies are eagerly awaited. Even new functional food products could have the potential to positively influence cardiometabolic regulation, to be confirmed.

  6. Early Years Practitioners' Views on Early Personal, Social and Emotional Development

    ERIC Educational Resources Information Center

    Aubrey, Carol; Ward, Karen

    2013-01-01

    Current policy guidance stresses the need for early identification of obstacles to learning and appropriate intervention. New standards for learning (Early Years Foundation Stage) place personal, social and emotional development (PSED) as central to learning and development. This paper reports a survey and follow-up interviews with early years…

  7. Pluripotency and lineages in the mammalian blastocyst: an evolutionary view.

    PubMed

    Cañon, Susana; Fernandez-Tresguerres, Beatriz; Manzanares, Miguel

    2011-06-01

    Early mammalian development is characterized by a highly specific stage, the blastocyst, by which embryonic and extraembryonic lineages have been determined, but pattern formation has not yet begun. The blastocyst is also of interest because cell precursors of the embryo proper retain for a certain time the capability to generate all the cell types of the adult animal. This embryonic pluripotency is established and maintained by a regulatory network under the control of a small set of transcription factors, comprising Oct4, Sox2 and Nanog. This network is largely conserved in eutherian mammals, but there is scarce information about how it arose in vertebrates. We have analysed the conservation of gene regulatory networks controlling blastocyst lineages and pluripotency in the mouse by comparison with the chick. We found that few of elements of the network are novel to mammals; rather, most of them were present before the separation of the mammalian lineage from other amniotes, but acquired novel expression domains during early mammalian development. Our results strongly support the hypothesis that mammalian blastocyst regulatory networks evolved through rewiring of pre-existing components, involving the co-option and duplication of existing genes and the establishment of new regulatory interactions among them.

  8. Early Parental Depression and Child Language Development

    ERIC Educational Resources Information Center

    Paulson, James F.; Keefe, Heather A.; Leiferman, Jenn A.

    2009-01-01

    Objective: To examine the effects of early maternal and paternal depression on child expressive language at age 24 months and the role that parent-to-child reading may play in this pathway. Participants and methods: The 9-month and 24-month waves from a national prospective study of children and their families, the Early Childhood Longitudinal…

  9. The early research and development of ebselen.

    PubMed

    Parnham, Michael J; Sies, Helmut

    2013-11-01

    Ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one; PZ-51, DR-3305), is an organoselenium compound with glutathione peroxidase (GPx)-like, thiol-dependent, hydroperoxide reducing activity. As an enzyme mimic for activity of the selenoenzyme GPx, this compound has proved to be highly useful in research on mechanisms in redox biology. Furthermore, the reactivity of ebselen with protein thiols has helped to identify novel, selective targets for inhibitory actions on several enzymes of importance in pharmacology and toxicology. Importantly, the selenium in ebselen is not released and thus is not bioavailable, ebselen metabolites being excreted in bile and urine. As a consequence, initial concerns about selenium toxicity, fortunately, were unfounded. Potential applications in medical settings have been explored, notably in brain ischemia and stroke. More recently, there has been a surge in interest as new medical applications have been taken into consideration. The first publication on the biochemical effects of ebselen appeared 30 years ago (Müller et al.), which prompted the authors to retrace the early development from their perspective. It is a fascinating example of fruitful interaction between research-oriented industry and academia. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Parental Obesity and Early Childhood Development.

    PubMed

    Yeung, Edwina H; Sundaram, Rajeshwari; Ghassabian, Akhgar; Xie, Yunlong; Buck Louis, Germaine

    2017-02-01

    Previous studies identified associations between maternal obesity and childhood neurodevelopment, but few examined paternal obesity despite potentially distinct genetic/epigenetic effects related to developmental programming. Upstate KIDS (2008-2010) recruited mothers from New York State (excluding New York City) at ∼4 months postpartum. Parents completed the Ages and Stages Questionnaire (ASQ) when their children were 4, 8, 12, 18, 24, 30, and 36 months of age corrected for gestation. The ASQ is validated to screen for delays in 5 developmental domains (ie, fine motor, gross motor, communication, personal-social functioning, and problem-solving ability). Analyses included 3759 singletons and 1062 nonrelated twins with ≥1 ASQs returned. Adjusted odds ratios (aORs) and 95% confidence intervals were estimated by using generalized linear mixed models accounting for maternal covariates (ie, age, race, education, insurance, marital status, parity, and pregnancy smoking). Compared with normal/underweight mothers (BMI <25), children of obese mothers (26% with BMI ≥30) had increased odds of failing the fine motor domain (aOR 1.67; confidence interval 1.12-2.47). The association remained after additional adjustment for paternal BMI (1.67; 1.11-2.52). Paternal obesity (29%) was associated with increased risk of failing the personal-social domain (1.75; 1.13-2.71), albeit attenuated after adjustment for maternal obesity (aOR 1.71; 1.08-2.70). Children whose parents both had BMI ≥35 were likely to additionally fail the problem-solving domain (2.93; 1.09-7.85). Findings suggest that maternal and paternal obesity are each associated with specific delays in early childhood development, emphasizing the importance of family information when screening child development. Copyright © 2017 by the American Academy of Pediatrics.

  11. Parental Obesity and Early Childhood Development

    PubMed Central

    Sundaram, Rajeshwari; Ghassabian, Akhgar; Xie, Yunlong; Buck Louis, Germaine

    2017-01-01

    BACKGROUND: Previous studies identified associations between maternal obesity and childhood neurodevelopment, but few examined paternal obesity despite potentially distinct genetic/epigenetic effects related to developmental programming. METHODS: Upstate KIDS (2008–2010) recruited mothers from New York State (excluding New York City) at ∼4 months postpartum. Parents completed the Ages and Stages Questionnaire (ASQ) when their children were 4, 8, 12, 18, 24, 30, and 36 months of age corrected for gestation. The ASQ is validated to screen for delays in 5 developmental domains (ie, fine motor, gross motor, communication, personal-social functioning, and problem-solving ability). Analyses included 3759 singletons and 1062 nonrelated twins with ≥1 ASQs returned. Adjusted odds ratios (aORs) and 95% confidence intervals were estimated by using generalized linear mixed models accounting for maternal covariates (ie, age, race, education, insurance, marital status, parity, and pregnancy smoking). RESULTS: Compared with normal/underweight mothers (BMI <25), children of obese mothers (26% with BMI ≥30) had increased odds of failing the fine motor domain (aOR 1.67; confidence interval 1.12–2.47). The association remained after additional adjustment for paternal BMI (1.67; 1.11–2.52). Paternal obesity (29%) was associated with increased risk of failing the personal-social domain (1.75; 1.13–2.71), albeit attenuated after adjustment for maternal obesity (aOR 1.71; 1.08–2.70). Children whose parents both had BMI ≥35 were likely to additionally fail the problem-solving domain (2.93; 1.09–7.85). CONCLUSIONS: Findings suggest that maternal and paternal obesity are each associated with specific delays in early childhood development, emphasizing the importance of family information when screening child development. PMID:28044047

  12. Bridging the gap: facilities and technologies for development of early stage therapeutic mAb candidates.

    PubMed

    Munro, Trent P; Mahler, Stephen M; Huang, Edwin P; Chin, David Y; Gray, Peter P

    2011-01-01

    Therapeutic monoclonal antibodies (mAbs) currently dominate the biologics marketplace. Development of a new therapeutic mAb candidate is a complex, multistep process and early stages of development typically begin in an academic research environment. Recently, a number of facilities and initiatives have been launched to aid researchers along this difficult path and facilitate progression of the next mAb blockbuster. Complementing this, there has been a renewed interest from the pharmaceutical industry to reconnect with academia in order to boost dwindling pipelines and encourage innovation. In this review, we examine the steps required to take a therapeutic mAb from discovery through early stage preclinical development and toward becoming a feasible clinical candidate. Discussion of the technologies used for mAb discovery, production in mammalian cells and innovations in single-use bioprocessing is included. We also examine regulatory requirements for product quality and characterization that should be considered at the earliest stages of mAb development. We provide details on the facilities available to help researchers and small-biotech build value into early stage product development, and include examples from within our own facility of how technologies are utilized and an analysis of our client base.

  13. Assessment of the expression and role of the α1-nAChR subunit in efferent cholinergic function during the development of the mammalian cochlea

    PubMed Central

    Wu (武靜靜), Jingjing Sherry; McIntosh, J. Michael; Glowatzki, Elisabeth

    2016-01-01

    Hair cell (HC) activity in the mammalian cochlea is modulated by cholinergic efferent inputs from the brainstem. These inhibitory inputs are mediated by calcium-permeable nicotinic acetylcholine receptors (nAChRs) containing α9- and α10-subunits and by subsequent activation of calcium-dependent potassium channels. Intriguingly, mRNAs of α1- and γ-nAChRs, subunits of the “muscle-type” nAChR have also been found in developing HCs (Cai T, Jen HI, Kang H, Klisch TJ, Zoghbi HY, Groves AK. J Neurosci 35: 5870–5883, 2015; Scheffer D, Sage C, Plazas PV, Huang M, Wedemeyer C, Zhang DS, Chen ZY, Elgoyhen AB, Corey DP, Pingault V. J Neurochem 103: 2651–2664, 2007; Sinkkonen ST, Chai R, Jan TA, Hartman BH, Laske RD, Gahlen F, Sinkkonen W, Cheng AG, Oshima K, Heller S. Sci Rep 1: 26, 2011) prompting proposals that another type of nAChR is present and may be critical during early synaptic development. Mouse genetics, histochemistry, pharmacology, and whole cell recording approaches were combined to test the role of α1-nAChR subunit in HC efferent synapse formation and cholinergic function. The onset of α1-mRNA expression in mouse HCs was found to coincide with the onset of the ACh response and efferent synaptic function. However, in mouse inner hair cells (IHCs) no response to the muscle-type nAChR agonists (±)-anatoxin A, (±)-epibatidine, (−)-nicotine, or 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP) was detected, arguing against the presence of an independent functional α1-containing muscle-type nAChR in IHCs. In α1-deficient mice, no obvious change of IHC efferent innervation was detected at embryonic day 18, contrary to the hyperinnervation observed at the neuromuscular junction. Additionally, ACh response and efferent synaptic activity were detectable in α1-deficient IHCs, suggesting that α1 is not necessary for assembly and membrane targeting of nAChRs or for efferent synapse formation in IHCs. PMID:27098031

  14. Assessment of the expression and role of the α1-nAChR subunit in efferent cholinergic function during the development of the mammalian cochlea.

    PubMed

    Roux, Isabelle; Wu, Jingjing Sherry; McIntosh, J Michael; Glowatzki, Elisabeth

    2016-08-01

    Hair cell (HC) activity in the mammalian cochlea is modulated by cholinergic efferent inputs from the brainstem. These inhibitory inputs are mediated by calcium-permeable nicotinic acetylcholine receptors (nAChRs) containing α9- and α10-subunits and by subsequent activation of calcium-dependent potassium channels. Intriguingly, mRNAs of α1- and γ-nAChRs, subunits of the "muscle-type" nAChR have also been found in developing HCs (Cai T, Jen HI, Kang H, Klisch TJ, Zoghbi HY, Groves AK. J Neurosci 35: 5870-5883, 2015; Scheffer D, Sage C, Plazas PV, Huang M, Wedemeyer C, Zhang DS, Chen ZY, Elgoyhen AB, Corey DP, Pingault V. J Neurochem 103: 2651-2664, 2007; Sinkkonen ST, Chai R, Jan TA, Hartman BH, Laske RD, Gahlen F, Sinkkonen W, Cheng AG, Oshima K, Heller S. Sci Rep 1: 26, 2011) prompting proposals that another type of nAChR is present and may be critical during early synaptic development. Mouse genetics, histochemistry, pharmacology, and whole cell recording approaches were combined to test the role of α1-nAChR subunit in HC efferent synapse formation and cholinergic function. The onset of α1-mRNA expression in mouse HCs was found to coincide with the onset of the ACh response and efferent synaptic function. However, in mouse inner hair cells (IHCs) no response to the muscle-type nAChR agonists (±)-anatoxin A, (±)-epibatidine, (-)-nicotine, or 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP) was detected, arguing against the presence of an independent functional α1-containing muscle-type nAChR in IHCs. In α1-deficient mice, no obvious change of IHC efferent innervation was detected at embryonic day 18, contrary to the hyperinnervation observed at the neuromuscular junction. Additionally, ACh response and efferent synaptic activity were detectable in α1-deficient IHCs, suggesting that α1 is not necessary for assembly and membrane targeting of nAChRs or for efferent synapse formation in IHCs.

  15. Self-illuminating quantum dots for non-invasive bioluminescence imaging of mammalian

    USDA-ARS?s Scientific Manuscript database

    Background: The fertility performance of animals is still a mystery and the full comprehension of mammalian gametes maturation and early embryonic development remains to be elucidated. The recent development in nanotechnology offers a new opportunity for real-time study of reproductive cells in thei...

  16. Aquaporin 0 plays a pivotal role in refractive index gradient development in mammalian eye lens to prevent spherical aberration

    SciTech Connect

    Kumari, S. Sindhu; Varadaraj, Kulandaiappan, E-mail: kulandaiappan.varadaraj@stonybrook.edu; SUNY Eye Institute, New York, NY

    Highlights: • Intact AQP0 functions as fiber cell-to-fiber cell adhesion protein. • AQP0 facilitates reduction in extracellular space and lens water content. • AQP0 adhesion function aids in lens refractive index gradient (RING) formation. • AQP0 prevents lens spherical aberration by establishing RING. • AQP0 is critical for lens transparency and homeostasis. - Abstract: Aquaporin 0 (AQP0) is a transmembrane channel that constitutes ∼45% of the total membrane protein of the fiber cells in mammalian lens. It is critical for lens transparency and homeostasis as mutations and knockout cause autosomal dominant lens cataract. AQP0 functions as a water channel andmore » as a cell-to-cell adhesion (CTCA) molecule in the lens. Our recent in vitro studies showed that the CTCA function of AQP0 could be crucial to establish lens refractive index gradient (RING). However, there is a lack of in vivo data to corroborate the role of AQP0 as a fiber CTCA molecule which is critical for creating lens RING. The present investigation is undertaken to gather in vivo evidence for the involvement of AQP0 in developing lens RING. Lenses of wild type (WT) mouse, AQP0 knockout (heterozygous, AQP0{sup +/−}) and AQP0 knockout lens transgenically expressing AQP1 (heterozygous AQP0{sup +/−}/AQP1{sup +/−}) mouse models were used for the study. Data on AQP0 protein profile of intact and N- and/or C-terminal cleaved AQP0 in the lens by MALDI-TOF mass spectrometry and SDS–PAGE revealed that outer cortex fiber cells have only intact AQP0 of ∼28 kDa, inner cortical and outer nuclear fiber cells have both intact and cleaved forms, and inner nuclear fiber cells have only cleaved forms (∼26–24 kDa). Knocking out of 50% of AQP0 protein caused light scattering, spherical aberration (SA) and cataract. Restoring the lost fiber cell membrane water permeability (P{sub f}) by transgene AQP1 did not reinstate complete lens transparency and the mouse lenses showed light scattering and

  17. Early Intervention Paraprofessional Standards: Development and Field Validation

    ERIC Educational Resources Information Center

    Banerjee, Rashida; Chopra, Ritu V.; DiPalma, Geraldine

    2017-01-01

    Personnel standards are the foundations for how states and nations approve a program, engage in systemic assessment, and provide effective professional development to its early childhood professionals. However, despite the extensive use of paraprofessionals in early intervention/early childhood special education programs, there is a lack of…

  18. Early Developments in Argumentation in Physics.

    ERIC Educational Resources Information Center

    Bazerman, Charles

    An evaluation of four seventeenth and eighteenth century essays on optics revealed early trends in the evolution of scientific articles. The later articles showed a growing tendency to (1) separate practice from pure knowledge, (2) organize information around problems of knowledge and theory rather than around chronological events, (3) emphasize…

  19. The Development of Self-Regulation across Early Childhood

    ERIC Educational Resources Information Center

    Montroy, Janelle J.; Bowles, Ryan P.; Skibbe, Lori E.; McClelland, Megan M.; Morrison, Frederick J.

    2016-01-01

    The development of early childhood self-regulation is often considered an early life marker for later life successes. Yet little longitudinal research has evaluated whether there are different trajectories of self-regulation development across children. This study investigates the development of behavioral self-regulation between the ages of 3 and…

  20. Early Development and the Brain: Teaching Resources for Educators

    ERIC Educational Resources Information Center

    Gilkerson, Linda, Ed.; Klein, Rebecca, Ed.

    2008-01-01

    This nine-unit curriculum translates current scientific research on early brain development into practical suggestions to help early childhood professionals understand the reciprocal link between caregiving and brain development. The curriculum was created and extensively field-tested by the Erikson Institute Faculty Development Project on the…

  1. Parents' Role in the Early Head Start Children's Language Development

    ERIC Educational Resources Information Center

    Griswold, Cecelia Smalls

    2014-01-01

    The development of language during a child's early years has been linked to parental involvement. While Early Head Start (EHS) researchers have theorized that parental involvement is an important factor in language development, there has been little research on how parents view their roles in the language development process. The purpose of this…

  2. Classroom Effects of an Early Childhood Educator Professional Development Partnership

    ERIC Educational Resources Information Center

    Algozzine, Bob; Babb, Julie; Algozzine, Kate; Mraz, Maryann; Kissel, Brian; Spano, Sedra; Foxworth, Kimberly

    2011-01-01

    We evaluated an Early Childhood Educator Professional Development (ECEPD) project that provided high-quality, sustained, and intensive professional development designed to support developmentally appropriate instruction for preschool-age children based on the best available research on early childhood pedagogy, child development, and preschool…

  3. Early literacy and early numeracy: the value of including early literacy skills in the prediction of numeracy development.

    PubMed

    Purpura, David J; Hume, Laura E; Sims, Darcey M; Lonigan, Christopher J

    2011-12-01

    The purpose of this study was to examine whether early literacy skills uniquely predict early numeracy skills development. During the first year of the study, 69 3- to 5-year-old preschoolers were assessed on the Preschool Early Numeracy Skills (PENS) test and the Test of Preschool Early Literacy Skills (TOPEL). Participants were assessed again a year later on the PENS test and on the Applied Problems and Calculation subtests of the Woodcock-Johnson III Tests of Achievement. Three mixed effect regressions were conducted using Time 2 PENS, Applied Problems, and Calculation as the dependent variables. Print Knowledge and Vocabulary accounted for unique variance in the prediction of Time 2 numeracy scores. Phonological Awareness did not uniquely predict any of the mathematics domains. The findings of this study identify an important link between early literacy and early numeracy development. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Quality and cost assessment of a recombinant antibody fragment produced from mammalian, yeast and prokaryotic host cells: A case study prior to pharmaceutical development.

    PubMed

    Lebozec, Kristell; Jandrot-Perrus, Martine; Avenard, Gilles; Favre-Bulle, Olivier; Billiald, Philippe

    2018-09-25

    Monoclonal antibody fragments (Fab) are a promising class of therapeutic agents. Fabs are aglycosylated proteins and so many expression platforms have been developed including prokaryotic, yeast and mammalian cells. However, these platforms are not equivalent in terms of cell line development and culture time, product quality and possibly cost of production that greatly influence the success of a drug candidate's pharmaceutical development. This study is an assessment of the humanized Fab fragment ACT017 produced from two microorganisms (Escherichia coli and Pichia pastoris) and one mammalian cell host (CHO). Following low scale production and Protein L-affinity purification under generic conditions, physico-chemical and functional quality assessments were carried out prior to economic analysis of industrial scale production using a specialized software (Biosolve, Biopharm Services, UK). Results show higher titer production when using E. coli but associated with high heterogeneity of the protein content recovered in the supernatant. We also observed glycoforms of the Fab produced from P. pastoris, while Fab secreted from CHO was the most homogeneous despite a much longer culture time and slightly higher estimated cost of goods. This study may help inform future pharmaceutical development of this class of therapeutic proteins. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Conceptions of and Early Childhood Educators' Experiences in Early Childhood Professional Development Programs: A Qualitative Metasynthesis

    ERIC Educational Resources Information Center

    Brown, Christopher P.; Englehardt, Joanna

    2016-01-01

    Policy makers and early childhood stakeholders across the United States continue to seek policy solutions that improve early educators' instruction of young children. A primary vehicle for attaining this goal is professional development. This has led to an influx of empirical studies that seek to develop a set of best practices for professional…

  6. Constructivist Early Education for Moral Development.

    ERIC Educational Resources Information Center

    DeVries, Rheta; Hildebrandt, Carolyn; Zan, Betty

    2000-01-01

    Examines role that constructivist teachers play in fostering moral development in young children. Traces development of perspective taking, autonomy, and self- regulation, and examines effects of different teaching and parenting practices on children's character development. Provides suggestions for teachers to promote optimal moral development by…

  7. Redefining Leadership: Lessons from an Early Education Leadership Development Initiative

    ERIC Educational Resources Information Center

    Douglass, Anne

    2018-01-01

    This study examined how experienced early educators developed as change agents in the context of a leadership development program. Unlike in many other professions, experienced early educators lack opportunities to grow throughout their careers and access the supports they need to lead change in their classrooms, organizations, the profession, and…

  8. Promoting Professional Development for Physical Therapists in Early Intervention

    ERIC Educational Resources Information Center

    Catalino, Tricia; Chiarello, Lisa A.; Long, Toby; Weaver, Priscilla

    2015-01-01

    Early intervention service providers are expected to form cohesive teams to build the capacity of a family to promote their child's development. Given the differences in personnel preparation across disciplines of service providers, the Early Childhood Personnel Center is creating integrated and comprehensive professional development models for…

  9. Investments for Future: Early Childhood Development and Education

    ERIC Educational Resources Information Center

    Kartal, Hulya

    2007-01-01

    Investments relevant to the first years of life are directly connected to the future of societies. It can be argued that investments for early childhood development and education are one of the best ways of decreasing social inequality caused by adverse environments which hinder development in early ages and tackling poverty by reducing the rate…

  10. Assessing Home Environment for Early Child Development in Pakistan

    ERIC Educational Resources Information Center

    Nadeem, Sanober; Rafique, Ghazala; Khowaja, Liaquat; Yameen, Anjum

    2014-01-01

    Family environment plays a very important role in early child development and the availability of stimulating material in the early years of a child's life is crucial for optimising development. The Home Observation for Measurement of the Environment (HOME) inventory is one of the most widely used measures to assess the quality and quantity of…

  11. Early Communication Development and Intervention for Children with Autism

    ERIC Educational Resources Information Center

    Landa, Rebecca

    2007-01-01

    Autism is a neurodevelopmental disorder defined by impairments in social and communication development, accompanied by stereotyped patterns of behavior and interest. The focus of this paper is on the early development of communication in autism, and early intervention for impairments in communication associated with this disorder. An overview of…

  12. Comparative transcriptomics of early dipteran development

    PubMed Central

    2013-01-01

    Background Modern sequencing technologies have massively increased the amount of data available for comparative genomics. Whole-transcriptome shotgun sequencing (RNA-seq) provides a powerful basis for comparative studies. In particular, this approach holds great promise for emerging model species in fields such as evolutionary developmental biology (evo-devo). Results We have sequenced early embryonic transcriptomes of two non-drosophilid dipteran species: the moth midge Clogmia albipunctata, and the scuttle fly Megaselia abdita. Our analysis includes a third, published, transcriptome for the hoverfly Episyrphus balteatus. These emerging models for comparative developmental studies close an important phylogenetic gap between Drosophila melanogaster and other insect model systems. In this paper, we provide a comparative analysis of early embryonic transcriptomes across species, and use our data for a phylogenomic re-evaluation of dipteran phylogenetic relationships. Conclusions We show how comparative transcriptomics can be used to create useful resources for evo-devo, and to investigate phylogenetic relationships. Our results demonstrate that de novo assembly of short (Illumina) reads yields high-quality, high-coverage transcriptomic data sets. We use these data to investigate deep dipteran phylogenetic relationships. Our results, based on a concatenation of 160 orthologous genes, provide support for the traditional view of Clogmia being the sister group of Brachycera (Megaselia, Episyrphus, Drosophila), rather than that of Culicomorpha (which includes mosquitoes and blackflies). PMID:23432914

  13. History and early development of INCAP.

    PubMed

    Scrimshaw, Nevin S

    2010-02-01

    Nevin Scrimshaw was the founding Director of the Institute of Nutrition of Central America and Panama (INCAP), serving as Director from 1949 to 1961. In this article, he reviews the history of the founding of INCAP, including the role of the Rockefeller and Kellogg Foundations, the Central American governments, and the Pan American Health Organization. The objectives pursued by INCAP in its early years were to assess the nutrition and related health problems of Central America, to carry out research to find practical solutions to these problems, and to provide technical assistance to its member countries to implement solutions. INCAP pursued a strategy of selecting promising Central Americans for advanced education and training in the US who assumed positions of leadership on their return. After this early phase, talented non-Central Americans of diverse origins were brought to INCAP, as well as additional researchers from the region. Growth of INCAP, as reflected in its annual budget and in the physical plant, was rapid and this was accompanied by high scientific productivity. Several field studies were launched that contributed impetus and design elements for the Oriente Longitudinal Study, which is the focus of this supplement.

  14. Developments in early intervention for psychosis in Hong Kong.

    PubMed

    Wong, G H Y; Hui, C L M; Wong, D Y; Tang, J Y M; Chang, W C; Chan, S K W; Lee, E H M; Xu, J Q; Lin, J J X; Lai, D C; Tam, W; Kok, J; Chung, D W S; Hung, S F; Chen, E Y H

    2012-09-01

    The year 2011 marked the 10-year milestone of early intervention for psychosis in Hong Kong. Since 2001, the landscape of early psychosis services has changed markedly in Hong Kong. Substantial progress has been made in the areas of early intervention service implementation, knowledge generation, and public awareness promotion. Favourable outcomes attributable to the early intervention service are supported by solid evidence from local clinical research studies; early intervention service users showed improved functioning, ameliorated symptoms, and decreased hospitalisation and suicide rates. Continued development of early intervention in Hong Kong over the decade includes the introduction and maturation of several key platforms, such as the Hospital Authority Early Assessment Service for Young People with Psychosis programme, the Psychosis Studies and Intervention Unit by the University of Hong Kong, the Hong Kong Early Psychosis Intervention Society, the Jockey Club Early Psychosis Project, and the postgraduate Psychological Medicine (Psychosis Studies) programme. In this paper, we reviewed some of the major milestones in local service development with reference to features of the Hong Kong mental health system. We describe chronologically the implementation and consolidation of public early intervention services as well as recent progresses in public awareness work that are tied in with knowledge generation and transfer, and outline the prospects for early intervention in the next decade and those that follow.

  15. Sex Role Development in Early Adolescence.

    ERIC Educational Resources Information Center

    Wittig, Michele Andrisin

    1983-01-01

    Research involving adolescent identification with and development of sex roles is reviewed in the areas of cognitive skills and personality traits, theories of sex role development, and minority group adolescent sex role development. Emerging issues and educational implications in these areas are discussed. (CJ)

  16. Early Numeracy Assessment: The Development of the Preschool Early Numeracy Scales

    ERIC Educational Resources Information Center

    Purpura, David J.; Lonigan, Christopher J.

    2015-01-01

    Research Findings: The focus of this study was to construct and validate 12 brief early numeracy assessment tasks that measure the skills and concepts identified as key to early mathematics development by the National Council of Teachers of Mathematics (2006) and the National Mathematics Advisory Panel (2008)-as well as critical developmental…

  17. Parents Resourcing Children's Early Development and Learning

    ERIC Educational Resources Information Center

    Nichols, Sue; Nixon, Helen; Pudney, Valerie; Jurvansuu, Sari

    2009-01-01

    Parents deal with a complex web of choices when seeking and using knowledge and resources related to their young children's literacy development. Information concerning children's learning and development comes in many forms and is produced by an increasingly diverse range of players including governments, non-government organizations and…

  18. Early psychosis workforce development: Core competencies for mental health professionals working in the early psychosis field.

    PubMed

    Osman, Helen; Jorm, Anthony F; Killackey, Eoin; Francey, Shona; Mulcahy, Dianne

    2017-08-09

    The aim of this study was to identify the core competencies required of mental health professionals working in the early psychosis field, which could function as an evidence-based tool to support the early psychosis workforce and in turn assist early psychosis service implementation and strengthen early psychosis model fidelity. The Delphi method was used to establish expert consensus on the core competencies. In the first stage, a systematic literature search was conducted to generate competency items. In the second stage, a panel consisting of expert early psychosis clinicians from around the world was formed. Panel members then rated each of the competency items on how essential they are to the clinical practice of all early psychosis clinicians. In total, 1023 pieces of literature including textbooks, journal articles and grey literature were reviewed. A final 542 competency items were identified for inclusion in the questionnaire. A total of 63 early psychosis experts participated in 3 rating rounds. Of the 542 competency items, 242 were endorsed as the required core competencies. There were 29 competency items that were endorsed by 62 or more experts, and these may be considered the foundational competencies for early psychosis practice. The study generated a set of core competencies that provide a common language for early psychosis clinicians across professional disciplines and country of practice, and potentially are a useful professional resource to support early psychosis workforce development and service reform. © 2017 John Wiley & Sons Australia, Ltd.

  19. Notch intracellular domain deficiency in nuclear localization activity retains the ability to enhance neural stem cell character and block neurogenesis in mammalian brain development.

    PubMed

    Jang, Jiwon; Byun, Sung-Hyun; Han, Dasol; Lee, Junsub; Kim, Juwan; Lee, Nayeon; Kim, Inhee; Park, Soojeong; Ha, Soobong; Kwon, Mookwang; Ahn, Jyhyun; Chung, Woo-Jae; Kweon, Dae-Hyuk; Cho, Jae Youl; Kim, Sunyoung; Yoon, Keejung

    2014-12-01

    Notch has a broad range of regulatory functions in many developmental processes, including hematopoiesis, neurogenesis, and angiogenesis. Notch has several key functional regions such as the RBP-Jκ/CBF1 association module (RAM) domain, nuclear localization signals (NLS), and ankyrin (ANK) repeats. However, previous reports assessing the level of importance of these domains in the Notch signaling pathway are controversial. In this study, we have assessed the level of contribution of each Notch domain to the regulation of mammalian neural stem cells in vivo as well as in vitro. Reporter assays and real-time polymerase chain reactions show that the ANK repeats and RAM domain are indispensable to the transactivation of Notch target genes, whereas a nuclear export signal (NES)-fused Notch intracellular domain (NICD) mutant defective in nuclear localization exerts a level of activity comparable to unmodified NICD. Transactivational ability appears to be tightly coupled to Notch functions during brain development. Unlike ANK repeats and RAM domain deletion mutants, NES-NICD recapitulates NICD features such as promotion of astrogenesis at the expense of neurogenesis in vitro and enhancement of neural stem cell character in vivo. Our data support the previous observation that intranuclear localization is not essential to the oncogenesis of Notch1 in certain types of cells and imply the importance of the noncanonical Notch signaling pathway in the regulation of mammalian neural stem cells.

  20. Early development of fern gametophytes in microgravity

    NASA Technical Reports Server (NTRS)

    Roux, Stanley J.; Chatterjee, Ani; Hillier, Sheila; Cannon, Tom

    2003-01-01

    Dormant spores of the fern Ceratopteris richardii were flown on Shuttle mission STS-93 to evaluate the effects of micro-g on their development and on their pattern of gene expression. Prior to flight the spores were sterilized and sown into one of two environments: (1) Microscope slides in a video-microscopy module; and (2) Petri dishes. All spores were then stored in darkness until use. Spore germination was initiated on orbit after exposure to light. For the spores on microscope slides, cell level changes were recorded through the clear spore coat of the spores by video microscopy. After their exposure to light, spores in petri dishes were frozen in orbit at four different time points during which on earth gravity fixes the polarity of their development. Spores were then stored frozen in Biological Research in Canister units until recovery on earth. The RNAs from these cells and from 1-g control cells were extracted and analyzed on earth after flight to assay changes in gene expression. Video microscopy results revealed that the germinated spores developed normally in microgravity, although the polarity of their development, which is guided by gravity on earth, was random in space. Differential Display-PCR analyses of RNA extracted from space-flown cells showed that there was about a 5% change in the pattern of gene expression between cells developing in micro-g compared to those developing on earth. c2002 Published by Elsevier Science Ltd on behalf of COSPAR.

  1. Photodynamic Inactivation of Mammalian Viruses and Bacteriophages

    PubMed Central

    Costa, Liliana; Faustino, Maria Amparo F.; Neves, Maria Graça P. M. S.; Cunha, Ângela; Almeida, Adelaide

    2012-01-01

    Photodynamic inactivation (PDI) has been used to inactivate microorganisms through the use of photosensitizers. The inactivation of mammalian viruses and bacteriophages by photosensitization has been applied with success since the first decades of the last century. Due to the fact that mammalian viruses are known to pose a threat to public health and that bacteriophages are frequently used as models of mammalian viruses, it is important to know and understand the mechanisms and photodynamic procedures involved in their photoinactivation. The aim of this review is to (i) summarize the main approaches developed until now for the photodynamic inactivation of bacteriophages and mammalian viruses and, (ii) discuss and compare the present state of the art of mammalian viruses PDI with phage photoinactivation, with special focus on the most relevant mechanisms, molecular targets and factors affecting the viral inactivation process. PMID:22852040

  2. Chaos, Poverty, and Parenting: Predictors of Early Language Development

    ERIC Educational Resources Information Center

    Vernon-Feagans, Lynne; Garrett-Peters, Patricia; Willoughby, Michael; Mills-Koonce, Roger

    2012-01-01

    Studies have shown that distal family risk factors like poverty and maternal education are strongly related to children's early language development. Yet, few studies have examined these risk factors in combination with more proximal day-to-day experiences of children that might be critical to understanding variation in early language. Young…

  3. Childhood Immunization: A Key Component of Early Childhood Development

    ERIC Educational Resources Information Center

    Messonnier, Nancy

    2017-01-01

    Physical health is a key component of early childhood development and school readiness. By keeping children healthy and decreasing the chances of disease outbreaks, immunizations help early childhood programs create a safe environment for children. While overall vaccination rates are high nationally for most vaccines routinely recommended for…

  4. Online Professional Development: Choices for Early Childhood Educators

    ERIC Educational Resources Information Center

    Olsen, Heather; Donaldson, Ana J.; Hudson, Susan D.

    2010-01-01

    Early childhood educators are responsible for providing young children with the best possible early care and education. Research on child care workers' education has shown that professional preparation makes a significant impact on children's cognitive and emotional development (National Association for the Education of Young Children [NAEYC],…

  5. Alberta Learning: Early Development Instrument Pilot Project Evaluation.

    ERIC Educational Resources Information Center

    Meaney, Wanda; Harris-Lorenze, Elayne

    The Early Development Instrument (EDI) was designed by McMaster University to measure the outcomes of childrens early years as they influence their readiness to learn at school. The EDI was piloted in several Canadian cities in recent years through two national initiatives. Building on these initiatives, Alberta Learning piloted the EDI as a…

  6. Activities for Career Development in Early Childhood Curriculum.

    ERIC Educational Resources Information Center

    Yawkey, Thomas Daniels; Aronin, Eugene L.

    The book presents career education activities and approaches for use by teachers, administrators, counselors, and students involved in early childhood education (ages three through eight). Part One stresses the importance of and rationale for career development in the early childhood curriculum. Research support for the approach to career…

  7. Family Strategies to Support and Develop Resilience in Early Childhood

    ERIC Educational Resources Information Center

    Taket, A. R.; Nolan, A.; Stagnitti, K.

    2014-01-01

    Early childhood is an important time for the development of resilience. A recently completed study has followed three cohorts of resilient children and young people living in disadvantaged areas in Victoria, Australia, through different transitions in their educational careers. This paper focuses on the early childhood cohort, where we have…

  8. Developing Prosocial Behaviors in Early Adolescence with Reactive Aggression

    ERIC Educational Resources Information Center

    Fung, Annis L. C.

    2008-01-01

    Despite the alarming rise of early adolescence aggression in Hong Kong, it is the pioneer evidence-based outcome study on Anger Coping Training (ACT) program for early adolescence with reactive aggression to develop their prosocial behaviors. This research program involved experimental and control groups with pre- and post-comparison using a …

  9. Early Speech Motor Development: Cognitive and Linguistic Considerations

    ERIC Educational Resources Information Center

    Nip, Ignatius S. B.; Green, Jordan R.; Marx, David B.

    2009-01-01

    This longitudinal investigation examines developmental changes in orofacial movements occurring during the early stages of communication development. The goals were to identify developmental trends in early speech motor performance and to determine how these trends differ across orofacial behaviors thought to vary in cognitive and linguistic…

  10. ECR-MAPK regulation in liver early development.

    PubMed

    Zhao, Xiu-Ju; Zhuo, Hexian

    2014-01-01

    Early growth is connected to a key link between embryonic development and aging. In this paper, liver gene expression profiles were assayed at postnatal day 22 and week 16 of age. Meanwhile another independent animal experiment and cell culture were carried out for validation. Significance analysis of microarrays, qPCR verification, drug induction/inhibition assays, and metabonomics indicated that alpha-2u globulin (extracellular region)-socs2 (-SH2-containing signals/receptor tyrosine kinases)-ppp2r2a/pik3c3 (MAPK signaling)-hsd3b5/cav2 (metabolism/organization) plays a vital role in early development. Taken together, early development of male rats is ECR and MAPK-mediated coordination of cancer-like growth and negative regulations. Our data represent the first comprehensive description of early individual development, which could be a valuable basis for understanding the functioning of the gene interaction network of infant development.

  11. Reading Development Subtypes and Their Early Characteristics

    ERIC Educational Resources Information Center

    Torppa, Minna; Tolvanen, Asko; Poikkeus, Anna-Maija; Eklund, Kenneth; Lerkkanen, Marja-Kristiina; Leskinen, Esko; Lyytinen, Heikki

    2007-01-01

    The present findings are drawn from the Jyvaskyla Longitudinal Study of Dyslexia (JLD), in which approximately 100 children with familial risk of dyslexia and 100 control children have been followed from birth. In this paper we report data on the reading development of the JLD children and their classmates, a total of 1,750 children from four…

  12. Developing an Engineering Identity in Early Childhood

    ERIC Educational Resources Information Center

    Pantoya, Michelle L.; Aguirre-Munoz, Zenaida; Hunt, Emily M.

    2015-01-01

    This project describes a strategy to introduce young children to engineering in a way that develops their engineering identity. The targeted age group is 3-7 year old students because they rarely experience purposeful engineering instruction. The curriculum was designed around an engineering storybook and included interactive academic discussions…

  13. Early developments in solar cooling equipment

    NASA Technical Reports Server (NTRS)

    Price, J. M.

    1978-01-01

    A brief description of a development program to design, fabricate and field test a series of solar operated or driven cooling devices, undertaken by the Marshall Space Flight Center in the context of the Solar Heating and Cooling Demonstration Act of 1974, is presented. Attention is given to two basic design concepts: the Rankine cycle principle and the use of a dessicant for cooling.

  14. School Building in Early Development. Part 2.

    ERIC Educational Resources Information Center

    Dijkgraaf, C.; Giertz, L. M.

    1975-01-01

    Development is characterized by urbanization. New settlements grow either as enlargements of existing ones or as new population concentrations. Three periods may be distinguished in the growth of a settlement: (1) the wild period of first settling, (2) the consolidation period, and (3) the stabilized society. The number of school-aged children per…

  15. Economic Deprivation and Early Childhood Development.

    ERIC Educational Resources Information Center

    Duncan, Greg J.; And Others

    1994-01-01

    Examined the relationship between poverty and children's developmental outcomes, the effects of the timing and duration of poverty, and the effects of poverty at the family and neighborhood level, analyzing data from two longitudinal surveys. Found that poverty status was strongly related to low levels of cognitive development, even after…

  16. The Early Development of Programmable Machinery.

    ERIC Educational Resources Information Center

    Collins, Martin D.

    1985-01-01

    Programmable equipment innovations, precursors of today's technology, are examined, including the development of the binary code and feedback control systems, such as temperature sensing devices, interchangeable parts, punched cards carrying instructions, continuous flow oil refining process, assembly lines for mass production, and the…

  17. The cellular code for mammalian thermosensation.

    PubMed

    Pogorzala, Leah A; Mishra, Santosh K; Hoon, Mark A

    2013-03-27

    Mammalian somatosenory neurons respond to thermal stimuli and allow animals to reliably discriminate hot from cold and to select their preferred environments. Previously, we generated mice that are completely insensitive to temperatures from noxious cold to painful heat (-5 to 55°C) by ablating several different classes of nociceptor early in development. In the present study, we have adopted a selective ablation strategy in adult mice to study this phenotype and have demonstrated that separate populations of molecularly defined neurons respond to hot and cold. TRPV1-expressing neurons are responsible for all behavioral responses to temperatures between 40 and 50°C, whereas TRPM8 neurons are required for cold aversion. We also show that more extreme cold and heat activate additional populations of nociceptors, including cells expressing Mrgprd. Therefore, although eliminating Mrgprd neurons alone does not affect behavioral responses to temperature, when combined with ablation of TRPV1 or TRPM8 cells, it significantly decreases responses to extreme heat and cold, respectively. Ablation of TRPM8 neurons distorts responses to preferred temperatures, suggesting that the pleasant thermal sensation of warmth may in fact just reflect reduced aversive input from TRPM8 and TRPV1 neurons. As predicted by this hypothesis, mice lacking both classes of thermosensor exhibited neither aversive nor attractive responses to temperatures between 10 and 50°C. Our results provide a simple cellular basis for mammalian thermosensation whereby two molecularly defined classes of sensory neurons detect and encode both attractive and aversive cues.

  18. Plasticity during Early Brain Development Is Determined by Ontogenetic Potential.

    PubMed

    Krägeloh-Mann, Ingeborg; Lidzba, Karen; Pavlova, Marina A; Wilke, Marko; Staudt, Martin

    2017-04-01

    Two competing hypotheses address neuroplasticity during early brain development: the "Kennard principle" describes the compensatory capacities of the immature developing CNS as superior to those of the adult brain, whereas the "Hebb principle" argues that the young brain is especially sensitive to insults. We provide evidence that these principles are not mutually exclusive. Following early brain lesions that are unilateral, the brain can refer to homotopic areas of the healthy hemisphere. This potential for reorganization is unique to the young brain but available only when, during ontogenesis of brain development, these areas have been used for the functions addressed. With respect to motor function, ipsilateral motor tracts can be recruited, which are only available during early brain development. Language can be reorganized to the right after early left hemispheric lesions, as the representation of the language network is initially bilateral. However, even in these situations, compensatory capacities of the developing brain are found to have limitations, probably defined by early determinants. Thus, plasticity and adaptivity are seen only within ontogenetic potential; that is, axonal or cortical structures cannot be recruited beyond early developmental possibilities. The young brain is probably more sensitive and vulnerable to lesions when these are bilateral. This is shown here for bilateral periventricular white matter lesions that clearly have an impact on cortical architecture and function, thus probably interfering with early network building. Georg Thieme Verlag KG Stuttgart · New York.

  19. Mammalian faunal response to the Early Eocene Climatic Optimum (~53.5-48.5 mya) and a new terrestrial record of the associated carbon isotope excursion from Raven Ridge in the Uinta Basin, Colorado-Utah

    NASA Astrophysics Data System (ADS)

    Dutchak, A. R.

    2010-12-01

    Raven Ridge straddles the Colorado-Utah border on the northeastern edge of the Uinta Basin and consists of intertonguing units of the fluvial Colton and lacustrine Green River Formations. Fossil vertebrate localities along the ridge have produced a diverse mammalian fauna comprising 64 genera in 34 families. Included are the index taxa Smilodectes, Omomys, Heptodon, and Lambdotherium which suggest an age range of mid-Wasatchian (Wa5, ~53.5mya) through mid Bridgerian (Br2, ~48.5mya) for the Raven Ridge fauna. Others have shown that this time interval coincides with the onset, peak, and decline of the Early Eocene Climatic Optimum (EECO), an extended interval of globally warm temperatures following the Paleocene-Eocene Thermal Maximum (PETM) that is coincident with a large negative carbon excursion. The Raven Ridge fauna provides an excellent opportunity to investigate the effects of a lengthy interval of global warmth on mammalian diversity and ecosystem structure. To study changes in the mammalian fauna that occurred during the EECO, it was necessary to constrain the onset, peak, and decline of the EECO at Raven Ridge through chemostratigraphic correlation with established marine isotope curves. This was accomplished by analysis of approximately 300 sediment samples for Total Organic Carbon (TOC) content. TOC has been used successfully in the Bighorn Basin to identify the stratigraphic occurrence of the Carbon Isotope Excursion (CIE) associated with the PETM, which has roughly the same amplitude as the negative excursion associated with the EECO. The Raven Ridge TOC data show a large negative carbon excursion that starts during the Wa6 biochron, peaks during the Wa7 biochron, and is followed by a positive excursion near the Wa-Br boundary. This terrestrial δ13C pattern is consistent with results seen in established marine isotope curves across the EECO interval. The minimum δ13C value of the negative excursion is -29.67‰, which is comparable to the Bighorn CIE

  20. Human transgenerational responses to early-life experience: potential impact on development, health and biomedical research

    PubMed Central

    Pembrey, Marcus; Saffery, Richard; Bygren, Lars Olov

    2014-01-01

    Mammalian experiments provide clear evidence of male line transgenerational effects on health and development from paternal or ancestral early-life exposures such as diet or stress. The few human observational studies to date suggest (male line) transgenerational effects exist that cannot easily be attributed to cultural and/or genetic inheritance. Here we summarise relevant studies, drawing attention to exposure sensitive periods in early life and sex differences in transmission and offspring outcomes. Thus, variation, or changes, in the parental/ancestral environment may influence phenotypic variation for better or worse in the next generation(s), and so contribute to common, non-communicable disease risk including sex differences. We argue that life-course epidemiology should be reframed to include exposures from previous generations, keeping an open mind as to the mechanisms that transmit this information to offspring. Finally, we discuss animal experiments, including the role of epigenetic inheritance and non-coding RNAs, in terms of what lessons can be learnt for designing and interpreting human studies. This review was developed initially as a position paper by the multidisciplinary Network in Epigenetic Epidemiology to encourage transgenerational research in human cohorts. PMID:25062846

  1. New Postcranial Material of the Early Caseid Casea broilii Williston, 1910 (Synapsida: Caseidae) with a Review of the Evolution of the Sacrum in Paleozoic Non-Mammalian Synapsids

    PubMed Central

    LeBlanc, Aaron R. H.; Reisz, Robert R.

    2014-01-01

    Here we use the description of a new specimen of the small caseid synapsid Casea broilii that preserves the sacral, pelvic and hind limb regions in great detail and in three dimensions, as a unique opportunity to reevaluate the early stages in the evolution of the sacrum in the lineage that led to mammals. We place this new material in the context of sacral evolution in early caseid synapsids and conclude that the transition from two to three sacral vertebrae occurred in small-bodied species, suggesting that it was not an adaptation to heavy weight bearing. Furthermore, we compare descriptions of sacral anatomy among known early synapsids, including caseids, ophiacodontids, edaphosaurids, varanopids, and sphenacodontians and review sacral evolution in early synapsids. Based on the descriptions of new species of caseids, edaphosaurids, and varanopids over the past several decades, it is clear that a sacrum consisting of three vertebrae evolved independently at least four times in synapsids during the Late Carboniferous and Early Permian. Furthermore, similarities in the morphologies of the sacral vertebrae and ribs of these early synapsids lead us to conclude that an anterior caudal vertebra had been incorporated into the sacral series convergently in these groups. Given the repeated acquisition of a three-vertebra sacrum in early synapsids and no apparent link to body size, we argue that this sacral anatomy was related to more efficient terrestrial locomotion than to increased weight bearing. PMID:25545624

  2. Resource Prospector (RP) - Early Prototyping and Development

    NASA Technical Reports Server (NTRS)

    Andrews, D.; Colaprete, A.; Quinn, J.; Bluethmann, B.; Trimble, J.

    2015-01-01

    The Resource Prospector (RP) is an In-Situ Resource Utilization (ISRU) technology demonstration mission under study by the NASA Human Exploration and Operations Mission Directorate's (HEOMD) Advanced Exploration Systems (AES) Division. The mission, currently planned to launch in 2020, will demonstrate extraction of oxygen from lunar regolith to validate ISRU capability. The mission will address key Strategic Knowledge Gaps (SKGs) for robotic and human exploration to the Moon, Near Earth Asteroids (NEAs), and ultimately Mars, as well as meet the strategic goals of the Global Exploration Roadmap (GER), offered by the International Space Exploration Coordination Group (ISECG). In this roadmap, the use of local resources is specifically addressed relating to human exploration. RP will provide knowledge to inform the selection of future mission destinations, support the development of exploration systems, and reduce the risk associated with human exploration. Expanding human presence beyond low-Earth orbit to asteroids and Mars will require the maximum possible use of local materials, so-called in-situ resources. The moon presents a unique destination to conduct robotic investigations that advance ISRU capabilities, as well as providing significant exploration and science value. Lunar regolith contains useful resources such as oxygen, water, silicon, and light metals, like aluminum and titanium. Oxygen can be separated from the regolith for life support (breathable air), or used to create rocket propellant (oxidizer). Regolith can be used to protect against radiation exposure, be processed into solar cells, or used to manufacture construction materials such as bricks and glass. RP will characterize the constituents and distribution of water and other volatiles at the poles of the Moon, enabling innovative uses of local resources, in addition to validating ISRU capabilities. This capability, as well as a deeper understanding of regolith, will be valuable in the

  3. Early intestinal growth and development in poultry.

    PubMed

    Lilburn, M S; Loeffler, S

    2015-07-01

    While there are many accepted "facts" within the field of poultry science that are in truth still open for discussion, there is little debate with respect to the tremendous genetic progress that has been made with commercial broilers and turkeys (Havenstein et al., 2003, 2007). When one considers the changes in carcass development in poultry meat strains, these genetic "improvements" have not always been accompanied by correlated changes in other physiological systems and this can predispose some birds to developmental anomalies (i.e. ascites; Pavlidis et al., 2007; Wideman et al., 2013). Over the last decade, there has been increased interest in intestinal growth/health as poultry nutritionists have attempted to adopt new approaches to deal with the broader changes in the overall nutrition landscape. This landscape includes not only the aforementioned genetic changes but also a raft of governmental policies that have focused attention on the environment (phosphorus and nitrogen excretion), consumer pressure on the use of antibiotics, and renewable biofuels with its consequent effects on ingredient costs. Intestinal morphology has become a common research tool for assessing nutritional effects on the intestine but it is only one metric among many that can be used and histological results can often be interpreted in a variety of ways. This study will address the broader body of research on intestinal growth and development in commercial poultry and will attempt to integrate the topics of the intestinal: microbial interface and the role of the intestine as an immune tissue under the broad umbrella of intestinal physiology. © 2015 Poultry Science Association Inc.

  4. Advancing Early Childhood Development: from Science to Scale 1

    PubMed Central

    Black, Maureen M; Walker, Susan P; Fernald, Lia C H; Andersen, Christopher T; DiGirolamo, Ann M; Lu, Chunling; McCoy, Dana C; Fink, Günther; Shawar, Yusra R; Shiffman, Prof Jeremy; Devercelli, Amanda E; Wodon, Quentin T; Vargas-Barón, Emily; Grantham-McGregor, Sally

    2018-01-01

    Early childhood development programmes vary in coordination and quality, with inadequate and inequitable access, especially for children younger than 3 years. New estimates, based on proxy measures of stunting and poverty, indicate that 250 million children (43%) younger than 5 years in low-income and middle-income countries are at risk of not reaching their developmental potential. There is therefore an urgent need to increase multisectoral coverage of quality programming that incorporates health, nutrition, security and safety, responsive caregiving, and early learning. Equitable early childhood policies and programmes are crucial for meeting Sustainable Development Goals, and for children to develop the intellectual skills, creativity, and wellbeing required to become healthy and productive adults. In this paper, the first in a three part Series on early childhood development, we examine recent scientific progress and global commitments to early childhood development. Research, programmes, and policies have advanced substantially since 2000, with new neuroscientific evidence linking early adversity and nurturing care with brain development and function throughout the life course. PMID:27717614

  5. Mammalian meat allergy following a tick bite: a case report

    PubMed Central

    2018-01-01

    Abstract The alpha-gal allergy is an emerging IgE-mediated reaction against the galactose-alpha-1,3-galactose carbohydrate found in mammalian meats. Patients with this condition will develop anaphylactic symptoms 3–6 h after the ingestion of mammalian meat food products such as beef, pork or lamb. The prevalence of this allergy is drastically increasing and severe reactions including anaphylactic shock have been reported, yet many patients experience symptoms for years before a diagnosis is made. We describe the presentation, diagnosis and management of a patient with the alpha-gal allergy in attempt to improve early recognition and management of patients with this condition. PMID:29492269

  6. Apoptosis of Oligodendrocytes during Early Development Delays Myelination and Impairs Subsequent Responses to Demyelination

    PubMed Central

    Caprariello, Andrew V.; Batt, Courtney E.; Zippe, Ingrid; Romito-DiGiacomo, Rita R.; Karl, Molly

    2015-01-01

    During mammalian development, myelin-forming oligodendrocytes are generated and axons ensheathed according to a tightly regulated sequence of events. Excess premyelinating oligodendrocytes are eliminated by apoptosis and the timing of the onset of myelination in any specific CNS region is highly reproducible. Although the developing CNS recovers more effectively than the adult CNS from similar insults, it is unknown whether early loss of oligodendrocyte lineage cells leads to long-term functional deficits. To directly assess whether the loss of oligodendrocytes during early postnatal spinal cord development impacted oligodendrogenesis, myelination, and remyelination, transgenic mouse lines were generated in which a modified caspase-9 molecule allowed spatial and temporal control of the apoptotic pathway specifically in mature, myelin basic protein expressing oligodendrocytes (MBP-iCP9). Activating apoptosis in MBP+ cells of the developing spinal cord during the first postnatal week inhibited myelination. This inhibition was transient, and the levels of myelination largely returned to normal after 2 weeks. Despite robust developmental plasticity, MBP-iCP9-induced oligodendrocyte apoptosis compromised the rate and extent of adult remyelination. Remyelination failure correlated with a truncated proliferative response of oligodendrocyte progenitor cells, suggesting that depleting the oligodendrocyte pool during critical developmental periods compromises the regenerative response to subsequent demyelinating lesions. SIGNIFICANCE STATEMENT This manuscript demonstrates that early insults leading to oligodendrocyte apoptosis result in the impairment of recovery from demyelinating diseases in the adult. These studies begin to provide an initial understanding of the potential failure of recovery in insults, such as periventricular leukomalacia and multiple sclerosis. PMID:26468203

  7. 45 CFR 1304.21 - Education and early childhood development.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... as art, music, movement, and dialogue; (iii) Promoting interaction and language use among children... DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND... early childhood development. (a) Child development and education approach for all children. (1) In order...

  8. 45 CFR 1304.21 - Education and early childhood development.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... as art, music, movement, and dialogue; (iii) Promoting interaction and language use among children... DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND... early childhood development. (a) Child development and education approach for all children. (1) In order...

  9. 45 CFR 1304.21 - Education and early childhood development.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... as art, music, movement, and dialogue; (iii) Promoting interaction and language use among children... DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND... early childhood development. (a) Child development and education approach for all children. (1) In order...

  10. 45 CFR 1304.21 - Education and early childhood development.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... as art, music, movement, and dialogue; (iii) Promoting interaction and language use among children... DEVELOPMENT SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES THE ADMINISTRATION FOR CHILDREN, YOUTH AND... early childhood development. (a) Child development and education approach for all children. (1) In order...

  11. Early development of an enterprise health data warehouse.

    PubMed

    Househ, Mowafa Said; Al-Tuwaijri, Majid

    2011-01-01

    The purpose of this study is to describe early development challenges of an enterprise data warehouse within a Saudi Arabian academic healthcare facility. An action case research method was selected for this paper. The study took place between December 2009 and February 2010. Data collection included interviews, meeting observations, and meeting minutes. Early development challenges centered on the development of clear contracts with vendors; development of a clear project plan; a need to fast-track bureaucracy; and educate clinicians and staff about the project; and lack of data standardization.

  12. Reverse Genetics for Mammalian Orthoreovirus.

    PubMed

    Stuart, Johnasha D; Phillips, Matthew B; Boehme, Karl W

    2017-01-01

    Reverse genetics allows introduction of specific alterations into a viral genome. Studies performed with mutant viruses generated using reverse genetics approaches have contributed immeasurably to our understanding of viral replication and pathogenesis, and also have led to development of novel vaccines and virus-based vectors. Here, we describe the reverse genetics system that allows for production and recovery of mammalian orthoreovirus, a double-stranded (ds) RNA virus, from plasmids that encode the viral genome.

  13. Early Brain and Child Development: Connections to Early Education and Child Care

    ERIC Educational Resources Information Center

    Romano, Judith T.

    2013-01-01

    The vast majority of young children spend time in settings outside of the home, and the nature of those settings directly impacts the child's health and development. The ecobiodevelopmental framework of early brain and child development serve as the backdrop for establishing quality. This article describes the use of quality rating systems,…

  14. Integrated and Early Childhood Education: Preparation for Social Development. Theme A: Relevant Provision for Early Childhood.

    ERIC Educational Resources Information Center

    Axton, J. H. M.

    Factors which influence child development are listed and briefly discussed. These factors are (1) mother's childhood, (2) mother's age, (3) care during pregnancy and delivery, (4) early neonatal factors, (5) birth interval, (6) effect of repeated infection and malnutrition on brain growth and intellectual development, and (7) home environment. The…

  15. Getting an Early Start on Early Child Development. Education Notes. 30194

    ERIC Educational Resources Information Center

    Young, Mary Eming; Dunkelberg, Erika

    2004-01-01

    The children born this year--2004--will be eleven years old in 2015--the age of primary school completion in most countries. This is the MDG (Millennium Development Goal) generation--for whom the international community has pledged that by 2015, all children will be able to complete primary schooling. Ensuring good early child development is the…

  16. Responses to Cell Loss Become Restricted as the Supporting Cells in Mammalian Vestibular Organs Grow Thick Junctional Actin Bands That Develop High Stability

    PubMed Central

    Burns, Joseph C.

    2014-01-01

    Sensory hair cell (HC) loss is a major cause of permanent hearing and balance impairments for humans and other mammals. Yet, fish, amphibians, reptiles, and birds readily replace HCs and recover from such sensory deficits. It is unknown what prevents replacement in mammals, but cell replacement capacity declines contemporaneously with massive postnatal thickening of F-actin bands at the junctions between vestibular supporting cells (SCs). In non-mammals, SCs can give rise to regenerated HCs, and the bands remain thin even in adults. Here we investigated the stability of the F-actin bands between SCs in ears from chickens and mice and Madin-Darby canine kidney cells. Pharmacological experiments and fluorescence recovery after photobleaching (FRAP) of SC junctions in utricles from mice that express a γ-actin–GFP fusion protein showed that the thickening F-actin bands develop increased resistance to depolymerization and exceptional stability that parallels a sharp decline in the cell replacement capacity of the maturing mammalian ear. The FRAP recovery rate and the mobile fraction of γ-actin–GFP both decreased as the bands thickened with age and became highly stabilized. In utricles from neonatal mice, time-lapse recordings in the vicinity of dying HCs showed that numerous SCs change shape and organize multicellular actin purse strings that reseal the epithelium. In contrast, adult SCs appeared resistant to deformation, with resealing responses limited to just a few neighboring SCs that did not form purse strings. The exceptional stability of the uniquely thick F-actin bands at the junctions of mature SCs may play an important role in restricting dynamic repair responses in mammalian vestibular epithelia. PMID:24478379

  17. Responses to cell loss become restricted as the supporting cells in mammalian vestibular organs grow thick junctional actin bands that develop high stability.

    PubMed

    Burns, Joseph C; Corwin, Jeffrey T

    2014-01-29

    Sensory hair cell (HC) loss is a major cause of permanent hearing and balance impairments for humans and other mammals. Yet, fish, amphibians, reptiles, and birds readily replace HCs and recover from such sensory deficits. It is unknown what prevents replacement in mammals, but cell replacement capacity declines contemporaneously with massive postnatal thickening of F-actin bands at the junctions between vestibular supporting cells (SCs). In non-mammals, SCs can give rise to regenerated HCs, and the bands remain thin even in adults. Here we investigated the stability of the F-actin bands between SCs in ears from chickens and mice and Madin-Darby canine kidney cells. Pharmacological experiments and fluorescence recovery after photobleaching (FRAP) of SC junctions in utricles from mice that express a γ-actin-GFP fusion protein showed that the thickening F-actin bands develop increased resistance to depolymerization and exceptional stability that parallels a sharp decline in the cell replacement capacity of the maturing mammalian ear. The FRAP recovery rate and the mobile fraction of γ-actin-GFP both decreased as the bands thickened with age and became highly stabilized. In utricles from neonatal mice, time-lapse recordings in the vicinity of dying HCs showed that numerous SCs change shape and organize multicellular actin purse strings that reseal the epithelium. In contrast, adult SCs appeared resistant to deformation, with resealing responses limited to just a few neighboring SCs that did not form purse strings. The exceptional stability of the uniquely thick F-actin bands at the junctions of mature SCs may play an important role in restricting dynamic repair responses in mammalian vestibular epithelia.

  18. Promoting equity through integrated early child development and nutrition interventions.

    PubMed

    Black, Maureen M; Dewey, Kathryn G

    2014-01-01

    Sustainable development, a foundation of the post-2015 global agenda, depends on healthy and productive citizens. The origins of adult health begin early in life, stemming from genetic-environmental interactions that include adequate nutrition and opportunities for responsive learning. Inequities associated with inadequate nutrition and early learning opportunities can undermine children's health and development, thereby compromising their productivity and societal contributions. Transactional theory serves as a useful framework for examining the associations that link early child development and nutrition because it emphasizes the interplay that occurs between children and the environment, mediated through caregiver interactions. Although single interventions targeting early child development or nutrition can be effective, there is limited evidence on the development, implementation, evaluation, and scaling up of integrated interventions. This manuscript introduces a special edition of papers on six topics central to integrated child development/nutrition interventions: (1) review of integrated interventions; (2) methods and topics in designing integrated interventions; (3) economic considerations related to integrated interventions; (4) capacity-building considerations; (5) examples of integrated interventions; and (6) policy implications of integrated interventions. Ensuring the health and development of infants and young children through integrated child development/nutrition interventions promotes equity, a critical component of sustainable development. © 2014 New York Academy of Sciences.

  19. Early childhood traumatic development and its impact on gender identity.

    PubMed

    Cohen, Y

    2001-03-01

    The author clarifies issues of gender identity typical to contemporary Western societies. Nowadays, we tend to emphasize self-autonomy as the main target of the individual's development. In adolescence this may cause many questions as to the adolescent's conception of his or her gender and sexual identity. These questions are the outcome of early development, and thus early traumas may impact the entire gender development. In this context, trauma includes not only major violations such as sexual abuse, terror attacks, and so forth, but also comprises events heretofore considered minor.

  20. Early Learning and Development: Cultural-Historical Concepts in Play

    ERIC Educational Resources Information Center

    Fleer, Marilyn

    2010-01-01

    "Early Learning and Development" provides a unique synthesis of cultural-historical theory from Vygotsky, Elkonin and Leontiev in the 20th century to the ground-breaking research of scholars such as Siraj-Blatchford, Kratsova and Hedegaard today. It demonstrates how development and learning are culturally embedded and institutionally defined, and…

  1. Child Development, Early Childhood Education and Family Life: A Bibliography.

    ERIC Educational Resources Information Center

    Reardon, Beverly, Comp.

    This bibliographical listing of approximately 2500 books on child development, early childhood education and family life was compiled as a resource for parents and students. Books are listed alphabetically by author and are grouped according to the following categories: child development; observation of children; adolescence; language…

  2. Helping Families Connect Early Literacy with Social-Emotional Development

    ERIC Educational Resources Information Center

    Santos, Rosa Milagros; Fettig, Angel; Shaffer, LaShorage

    2012-01-01

    Early childhood educators know that home is a child's first learning environment. From birth, children are comforted by hearing and listening to their caregivers' voices. The language used by families supports young children's development of oral language skills. Exposure to print materials in the home also supports literacy development. Literacy…

  3. Aesthetic Experience and Early Language and Literacy Development

    ERIC Educational Resources Information Center

    Johnson, Helen L.

    2007-01-01

    The present paper explores the connections between theory and research in language development and aesthetic education and their implications for early childhood classroom practice. The present paper posits that arts experiences make a unique and vital contribution to the child's development of language and literacy, as well as to the sense of…

  4. Professional development session for early career scientists at SITC 2012

    PubMed Central

    2013-01-01

    The Society for Immunotherapy of Cancer (SITC) 2012 Professional Development Session was held as part of the SITC 27th Annual Meeting, Washington, DC, on October 24, 2012. The session was designed as a new opportunity for early career investigators to learn about relevant career development topics in a didactic setting. PMID:25742323

  5. Promising Directions for Research and Development in Early Childhood Education.

    ERIC Educational Resources Information Center

    Elliott, David L.

    A survey of research and development studies currently needed in early childhood education stresses child development and its relation to instruction. Topics which have been discussed are perception, oral language, concept formation, learning set, motivation, and the psychology of learning. Universities and public school systems working together…

  6. Instructional Development for Early Career Academics: An Overview of Impact

    ERIC Educational Resources Information Center

    Stes, Ann; Van Petegem, Peter

    2011-01-01

    Background: Over the past decades, the issue of improving teaching in higher education has been seriously addressed. Centres for instructional development, aimed at enhancing teaching, have been set up in many countries. Instructional development for early career academics is perceived to be of particular importance. Given the considerable…

  7. Early Markers of Vulnerable Language Skill Development in Galactosaemia

    ERIC Educational Resources Information Center

    Lewis, Fiona M.; Coman, David J.; Syrmis, Maryanne

    2014-01-01

    There are no known biomedical or genetic markers to identify which infants with galactosaemia (GAL) are most at risk of poor language skill development, yet pre-linguistic communicative "red flag" behaviours are recognised as early identifiers of heightened vulnerability to impaired language development. We report on pre-linguistic…

  8. Understanding Emotional Development: Helping Early Childhood Providers Better Support Families

    ERIC Educational Resources Information Center

    Edwards, Nicole Megan

    2012-01-01

    This article is intended to provide early childhood providers with a concise overview of emerging emotional development in young children (birth-5), the important role of primary caregivers, and the link between parenting, emotional development, and behavior. Specific suggestions that have been shared with urban Head Start mothers are offered,…

  9. Culture and Early Language Development: Implications for Assessment and Intervention

    ERIC Educational Resources Information Center

    Parada, Patricia M.

    2013-01-01

    The purpose of this qualitative study--"Culture and Early Language Development: Implications for Assessment and Intervention"--was to explore and describe the perceptions and beliefs of Salvadoran mothers of low socioeconomic status regarding the language development of their young children in order to identify cultural variations in…

  10. Bioenergetics of Mammalian Sperm Capacitation

    PubMed Central

    Ferramosca, Alessandra; Zara, Vincenzo

    2014-01-01

    After ejaculation, the mammalian male gamete must undergo the capacitation process, which is a prerequisite for egg fertilization. The bioenergetics of sperm capacitation is poorly understood despite its fundamental role in sustaining the biochemical and molecular events occurring during gamete activation. Glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) are the two major metabolic pathways producing ATP which is the primary source of energy for spermatozoa. Since recent data suggest that spermatozoa have the ability to use different metabolic substrates, the main aim of this work is to present a broad overview of the current knowledge on the energy-producing metabolic pathways operating inside sperm mitochondria during capacitation in different mammalian species. Metabolism of glucose and of other energetic substrates, such as pyruvate, lactate, and citrate, is critically analyzed. Such knowledge, besides its obvious importance for basic science, could eventually translate into the development of novel strategies for treatment of male infertility, artificial reproduction, and sperm selection methods. PMID:24791005

  11. Bioenergetics of mammalian sperm capacitation.

    PubMed

    Ferramosca, Alessandra; Zara, Vincenzo

    2014-01-01

    After ejaculation, the mammalian male gamete must undergo the capacitation process, which is a prerequisite for egg fertilization. The bioenergetics of sperm capacitation is poorly understood despite its fundamental role in sustaining the biochemical and molecular events occurring during gamete activation. Glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) are the two major metabolic pathways producing ATP which is the primary source of energy for spermatozoa. Since recent data suggest that spermatozoa have the ability to use different metabolic substrates, the main aim of this work is to present a broad overview of the current knowledge on the energy-producing metabolic pathways operating inside sperm mitochondria during capacitation in different mammalian species. Metabolism of glucose and of other energetic substrates, such as pyruvate, lactate, and citrate, is critically analyzed. Such knowledge, besides its obvious importance for basic science, could eventually translate into the development of novel strategies for treatment of male infertility, artificial reproduction, and sperm selection methods.

  12. Confocal Imaging of Early Heart Development in Xenopus laevis

    PubMed Central

    Kolker, Sandra J.; Tajchman, Urszula; Weeks, Daniel L.

    2013-01-01

    Xenopus laevis provides a number of advantages for studies on cardiovascular development. The embryos are fairly large, easy to obtain, and can develop at ambient temperature in simple buffer solutions. Although classic descriptions of heart development exist, the ability to use whole mount immunohistochemical methods and confocal microscopy may enhance the ability to understand both normal and experimentally perturbed cardiovascular development. We have started to examine the early stages of cardiac development in Xenopus, seeking to identify antibodies and fixatives that allow easy examination of the developing heart. We have used monoclonal antibodies (mAbs) raised against bovine cardiac troponin T and chicken tropomyosin to visualize cardiac muscle, a goat antibody recognizing bovine type VI collagen to stain the lining of vessels, and the JB3 mAb raised against chicken fibrillin which allows the visualization of a variety of cardiovascular tissues during early development. Results from embryonic stages 24–46 are presented. PMID:10644411

  13. Challenges in early clinical development of adjuvanted vaccines.

    PubMed

    Della Cioppa, Giovanni; Jonsdottir, Ingileif; Lewis, David

    2015-06-08

    A three-step approach to the early development of adjuvanted vaccine candidates is proposed, the goal of which is to allow ample space for exploratory and hypothesis-generating human experiments and to select dose(s) and dosing schedule(s) to bring into full development. Although the proposed approach is more extensive than the traditional early development program, the authors suggest that by addressing key questions upfront the overall time, size and cost of development will be reduced and the probability of public health advancement enhanced. The immunogenicity end-points chosen for early development should be critically selected: an established immunological parameter with a well characterized assay should be selected as primary end-point for dose and schedule finding; exploratory information-rich end-points should be limited in number and based on pre-defined hypothesis generating plans, including system biology and pathway analyses. Building a pharmacodynamic profile is an important aspect of early development: to this end, multiple early (within 24h) and late (up to one year) sampling is necessary, which can be accomplished by sampling subgroups of subjects at different time points. In most cases the final target population, even if vulnerable, should be considered for inclusion in early development. In order to obtain the multiple formulations necessary for the dose and schedule finding, "bed-side mixing" of various components of the vaccine is often necessary: this is a complex and underestimated area that deserves serious research and logistical support. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Zebrafish Craniofacial Development: A Window into Early Patterning

    PubMed Central

    Mork, Lindsey; Crump, Gage

    2016-01-01

    The formation of the face and skull involves a complex series of developmental events mediated by cells derived from the neural crest, endoderm, mesoderm, and ectoderm. Although vertebrates boast an enormous diversity of adult facial morphologies, the fundamental signaling pathways and cellular events that sculpt the nascent craniofacial skeleton in the embryo have proven to be highly conserved from fish to man. The zebrafish Danio rerio, a small freshwater cyprinid fish from eastern India, has served as a popular model of craniofacial development since the 1990s. Unique strengths of the zebrafish model include a simplified skeleton during larval stages, access to rapidly developing embryos for live imaging, and amenability to transgenesis and complex genetics. In this chapter, we describe the anatomy of the zebrafish craniofacial skeleton; its applications as models for the mammalian jaw, middle ear, palate, and cranial sutures; the superior imaging technology available in fish that has provided unprecedented insights into the dynamics of facial morphogenesis; the use of the zebrafish to decipher the genetic underpinnings of craniofacial biology; and finally a glimpse into the most promising future applications of zebrafish craniofacial research. PMID:26589928

  15. Development of Early Measures of Comprehension: Innovation in Individual Growth and Development Indicators

    ERIC Educational Resources Information Center

    Wackerle-Hollman, Alisha K.; Rodriguez, Megan I.; Bradfield, Tracy A.; Rodriguez, Michael C.; McConnell, Scott R.

    2015-01-01

    Early comprehension is an important, but not well-understood, contribution to early literacy and language development. Specifically, research regarding the nature of skills representative of early comprehension, including how they contribute to later reading success, is needed to support best practices to adequately prepare students. This article…

  16. Simplified Bioreactor For Growing Mammalian Cells

    NASA Technical Reports Server (NTRS)

    Spaulding, Glenn F.

    1995-01-01

    Improved bioreactor for growing mammalian cell cultures developed. Designed to support growth of dense volumes of mammalian cells by providing ample, well-distributed flows of nutrient solution with minimal turbulence. Cells relatively delicate and, unlike bacteria, cannot withstand shear forces present in turbulent flows. Bioreactor vessel readily made in larger sizes to accommodate greater cell production quantities. Molding equipment presently used makes cylinders up to 30 centimeters long. Alternative sintered plastic techniques used to vary pore size and quantity, as necessary.

  17. The effect of exposure to hypergravity on pregnant rat dams, pregnancy outcome and early neonatal development

    NASA Astrophysics Data System (ADS)

    Ladd, B.; Nguon, K.; Sajdel-Sulkowska, E. M.

    2006-01-01

    We previously reported that hypergravity exposure affects food intake and mass gain during pregnancy. In the present study, we explored the hypothesis that changes in maternal body mass in hypergravity-exposed pregnant rat dams affect pregnancy outcome and early offspring development. Furthermore, we hypothesized that the changes observed at 1.5G will be magnified at higher gravity and by exposure during critical developmental periods. To test this hypothesis, we compared maternal body mass gain, food consumption, birth outcome and early offspring development between Sprague Dawley rat dams exposed to graded (1.5 1.75G) chronic hypergravity (HG) or rotation (rotational control, RC) on a 24-ft centrifuge for 22.5 h starting on gestational day (G) 10 with dams housed under identical conditions but not exposed to hypergravity (SC). We also compared maternal body mass, food consumption, birth outcome and early offspring development between rat dams exposed to 1.65G during different stages of pregnancy and nursing. Exposure to hypergravity resulted in transient loss in body mass and prolonged decrease in food consumption in HG dams, but the changes observed at 1.5G were not magnified at 1.65G or 1.75G. On the other hand RC dams gained more mass and consumed more food than SC dams. Exposure to hypergravity also affected pregnancy outcome as evidenced by decreased litter size, lowered neonatal mass at birth, and higher neonatal mortality; pregnancy outcome was not affected in RC dams. Neonatal changes evidenced by impaired righting response observed at 1.5G was magnified at higher gravity and was dependent on the period of hypergravity exposure. On the other hand, righting response was improved in RC neonates. Hypergravity exposure during early postpartum affected the food consumption of nursing mothers and affected early survival of their offspring. The changes observed in dams and neonates appear to be due to hypergravity exposure since animals exposed to the rotation

  18. The development of self-regulation across early childhood.

    PubMed

    Montroy, Janelle J; Bowles, Ryan P; Skibbe, Lori E; McClelland, Megan M; Morrison, Frederick J

    2016-11-01

    The development of early childhood self-regulation is often considered an early life marker for later life successes. Yet little longitudinal research has evaluated whether there are different trajectories of self-regulation development across children. This study investigates the development of behavioral self-regulation between the ages of 3 and 7 years, with a direct focus on possible heterogeneity in the developmental trajectories, and a set of potential indicators that distinguish unique behavioral self-regulation trajectories. Across 3 diverse samples, 1,386 children were assessed on behavioral self-regulation from preschool through first grade. Results indicated that majority of children develop self-regulation rapidly during early childhood, and that children follow 3 distinct developmental patterns of growth. These 3 trajectories were distinguishable based on timing of rapid gains, as well as child gender, early language skills, and maternal education levels. Findings highlight early developmental differences in how self-regulation unfolds, with implications for offering individualized support across children. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  19. The Development of Self-Regulation across Early Childhood

    PubMed Central

    Montroy, Janelle J.; Bowles, Ryan P.; Skibbe, Lori E.; McClelland, Megan M.; Morrison, Frederick J.

    2016-01-01

    The development of early childhood self-regulation is often considered an early life marker for later life successes. Yet little longitudinal research has evaluated whether there are different trajectories of self-regulation development across children. This study investigates the development of behavioral self-regulation between the ages of three and seven, with a direct focus on possible heterogeneity in the developmental trajectories, and a set of potential indicators that distinguish unique behavioral self-regulation trajectories. Across three diverse samples, 1,386 children were assessed on behavioral self-regulation from preschool through first grade. Results indicated that majority of children develop self-regulation rapidly during early childhood, and that children follow three distinct developmental patterns of growth. These three trajectories were distinguishable based on timing of rapid gains, as well as child gender, early language skills, and maternal education levels. Findings highlight early developmental differences in how self-regulation unfolds with implications for offering individualized support across children. PMID:27709999

  20. The mammalian blastema: regeneration at our fingertips

    PubMed Central

    Simkin, Jennifer; Sammarco, Mimi C.; Dawson, Lindsay A.; Schanes, Paula P.; Yu, Ling

    2015-01-01

    Abstract In the mouse, digit tip regeneration progresses through a series of discrete stages that include inflammation, histolysis, epidermal closure, blastema formation, and redifferentiation. Recent studies reveal how each regenerative stage influences subsequent stages to establish a blastema that directs the successful regeneration of a complex mammalian structure. The focus of this review is on early events of healing and how an amputation wound transitions into a functional blastema. The stepwise formation of a mammalian blastema is proposed to provide a model for how specific targeted treatments can enhance regenerative performance in humans. PMID:27499871

  1. Mammalian pre-implantation chromosomal instability: species comparison, evolutionary considerations, and pathological correlations.

    PubMed

    Carbone, Lucia; Chavez, Shawn L

    2015-01-01

    Pre-implantation embryo development in mammals begins at fertilization with the migration and fusion of the maternal and paternal pro-nuclei, followed by the degradation of inherited factors involved in germ cell specification and the activation of embryonic genes required for subsequent cell divisions, compaction, and blastulation. The majority of studies on early embryogenesis have been conducted in the mouse or non-mammalian species, often requiring extrapolation of the findings to human development. Given both conserved similarities and species-specific differences, however, even comparison between closely related mammalian species may be challenging as certain aspects, including susceptibility to chromosomal aberrations, varies considerably across mammals. Moreover, most human embryo studies are limited to patient samples obtained from in vitro fertilization (IVF) clinics and donated for research, which are generally of poorer quality and produced with germ cells that may be sub-optimal. Recent technical advances in genetic, epigenetic, chromosomal, and time-lapse imaging analyses of high quality whole human embryos have greatly improved our understanding of early human embryogenesis, particularly at the single embryo and cell level. This review summarizes the major characteristics of mammalian pre-implantation development from a chromosomal perspective, in addition to discussing the technological achievements that have recently been developed to obtain this data. We also discuss potential translation to clinical applications in reproductive medicine and conclude by examining the broader implications of these findings for the evolution of mammalian species and cancer pathology in somatic cells.

  2. Temperament, Executive Control, and ADHD across Early Development

    PubMed Central

    Rabinovitz, Beth B.; O’Neill, Sarah; Rajendran, Khushmand; Halperin, Jeffrey M.

    2015-01-01

    Research examining factors linking early temperament and later ADHD is limited by cross-sectional approaches and having the same informant rate both temperament and psychopathology. We used multi-informant/multi-method longitudinal data to test the hypothesis that negative emotionality during preschool is positively associated with ADHD symptom severity in middle childhood, but developing executive control mediates this relation. Children (N=161) with and without ADHD were evaluated three times: Parent and teacher temperament ratings and NEPSY Visual Attention at ages 3–4 years; WISC-IV Working Memory Index and NEPSY Response Set at age 6 years; and ADHD symptoms using the Kiddie-SADS at age 7 years. Parent and teacher ratings of preschoolers’ temperament were combined to form an Anger/Frustration composite. Similarly, an Executive Functioning composite was derived from age 6 measures. Bootstrapping was used to determine whether age 6 Executive Functioning mediated the relation between early Anger/Frustration and later ADHD symptom severity, while controlling for early executive functioning. Preschoolers’ Anger/Frustration was significantly associated with later ADHD symptoms, with this relation partially mediated by age 6 Executive Functioning. Developing executive control mediates the relation between early Anger/Frustration and later ADHD symptom severity, suggesting that Anger/Frustration influences ADHD symptom severity through its impact on developing executive control. Early interventions targeting the harmful influences of negative emotionality or enhancing executive functioning may diminish later ADHD severity. PMID:26854505

  3. Embedded Professional Development and Classroom-Based Early Reading Intervention: Early Diagnostic Reading Intervention through Coaching

    ERIC Educational Resources Information Center

    Amendum, Steven J.

    2014-01-01

    The purpose of the current mixed-methods study was to investigate a model of professional development and classroom-based early reading intervention implemented by the 1st-grade teaching team in a large urban/suburban school district in the southeastern United States. The intervention provided teachers with ongoing embedded professional…

  4. New Hampshire Early Childhood Professional Development System: Guide to Early Childhood Careers.

    ERIC Educational Resources Information Center

    McDonnell, Tessa, Ed.

    The community of child care providers in New Hampshire has adopted the Early Childhood Professional Development System as an initial step toward assuring quality care and education for children. This guide describes the components of that system and is presented in eight sections. Section 1 of the guide introduces the system based on a set of two…

  5. The Australian Early Development Index: Reshaping Family-Child Relationships in Early Childhood Education

    ERIC Educational Resources Information Center

    Peers, Chris

    2011-01-01

    This article addresses the cultural significance of the Australian Early Development Index (AEDI) and discusses changes that the discourse of this instrument makes to the way in which the child is conceptualised. It analyses the technological function of the AEDI to examine how it makes the child a universal resource for human capital. The article…

  6. Early Learning Foundations. Indiana's Early Learning Development Framework Aligned to the Indiana Academic Standards, 2014

    ERIC Educational Resources Information Center

    Indiana Department of Education, 2015

    2015-01-01

    The "Foundations" (English/language arts, mathematics, social emotional skills, approaches to play and learning, science, social studies, creative arts, and physical health and growth) are Indiana's early learning development framework and are aligned to the 2014 Indiana Academic Standards. This framework provides core elements that…

  7. Early onset and differential temporospatial expression of melanopsin isoforms in the developing chicken retina.

    PubMed

    Verra, Daniela M; Contín, Maria Ana; Hicks, David; Guido, Mario E

    2011-07-07

    Retinal ganglion cells (RGCs) expressing the photopigment melanopsin (Opn4) display intrinsic photosensitivity. In this study, the presence of nonvisual phototransduction cascade components in the developing chicken retina and primary RGCs cultures was investigated, focusing on the two Opn4 genes: the Xenopus (Opn4x) and the mammalian (Opn4m) orthologs. Retinas were dissected at different embryonic (E) and postnatal (P) days, and primary RGC cultures were obtained at E8 and kept for 1 hour to 5 days. Samples were processed for RT-PCR and immunochemistry. Embryonic retinas expressed the master eye gene Pax6, the prospective RGC specification gene Brn3, and components of the nonvisual phototransduction cascade, such as Opn4m and the G protein q (Gq) mRNAs at very early stages (E4-E5). By contrast, expression of photoreceptor cell markers (CRX, red-opsin, rhodopsin, and α-transducin) was observed from E7 to E12. Opn4m protein was visualized in the whole retina as early as E4 and remained elevated from E6 to the postnatal days, whereas Opn4x was weakly detected at E8 and highly expressed after E11. RGC cultures expressed Gq mRNA, as well as both Opn4 mRNAs and proteins. Opn4m was restricted exclusively to the GC layer at all ages, whereas Opn4x was limited to the forming GC layer and optic nerve at E8, but by E15, its expression was mostly in Prox1(+) horizontal cells. The early expression onset of nonvisual phototransduction molecules could confer premature photosensitivity to RGCs, while the appearance of Opn4x expression in horizontal cells suggests the identification of a novel type of photosensitive cell in birds.

  8. Exploring the read-write genome: mobile DNA and mammalian adaptation.

    PubMed

    Shapiro, James A

    2017-02-01

    The read-write genome idea predicts that mobile DNA elements will act in evolution to generate adaptive changes in organismal DNA. This prediction was examined in the context of mammalian adaptations involving regulatory non-coding RNAs, viviparous reproduction, early embryonic and stem cell development, the nervous system, and innate immunity. The evidence shows that mobile elements have played specific and sometimes major roles in mammalian adaptive evolution by generating regulatory sites in the DNA and providing interaction motifs in non-coding RNA. Endogenous retroviruses and retrotransposons have been the predominant mobile elements in mammalian adaptive evolution, with the notable exception of bats, where DNA transposons are the major agents of RW genome inscriptions. A few examples of independent but convergent exaptation of mobile DNA elements for similar regulatory rewiring functions are noted.

  9. Early childhood obesity is associated with compromised cerebellar development.

    PubMed

    Miller, Jennifer L; Couch, Jessica; Schwenk, Krista; Long, Michelle; Towler, Stephen; Theriaque, Douglas W; He, Guojun; Liu, Yijun; Driscoll, Daniel J; Leonard, Christiana M

    2009-01-01

    As part of a study investigating commonalities between Prader-Willi syndrome (PWS-a genetic imprinting disorder) and early-onset obesity of unknown etiology (EMO) we measured total cerebral and cerebellar volume on volumetric magnetic resonance imaging (MRI) images. Individuals with PWS (N = 16) and EMO (N = 12) had smaller cerebellar volumes than a control group of 15 siblings (p = .02 control vs. EMO; p = .0005 control vs. PWS), although there was no difference among the groups in cerebral volume. Individuals with PWS and EMO also had impaired cognitive function: general intellectual ability (GIA): PWS 65 +/- 25; EMO 81 +/- 19; and Controls 112 +/- 13 (p < .0001 controls vs. PWS and controls vs. EMO). As both conditions are characterized by early-onset obesity and slowed cognitive development, these results raise the possibility that early childhood obesity retards both cerebellar and cognitive development.

  10. Fermitins, the Orthologs of Mammalian Kindlins, Regulate the Development of a Functional Cardiac Syncytium in Drosophila melanogaster

    PubMed Central

    Catterson, James H.; Heck, Margarete M. S.; Hartley, Paul S.

    2013-01-01

    The vertebrate Kindlins are an evolutionarily conserved family of proteins critical for integrin signalling and cell adhesion. Kindlin-2 (KIND2) is associated with intercalated discs in mice, suggesting a role in cardiac syncytium development; however, deficiency of Kind2 leads to embryonic lethality. Morpholino knock-down of Kind2 in zebrafish has a pleiotropic effect on development that includes the heart. It therefore remains unclear whether cardiomyocyte Kind2 expression is required for cardiomyocyte junction formation and the development of normal cardiac function. To address this question, the expression of Fermitin 1 and Fermitin 2 (Fit1, Fit2), the two Drosophila orthologs of Kind2, was silenced in Drosophila cardiomyocytes. Heart development was assessed in adult flies by immunological methods and videomicroscopy. Silencing both Fit1 and Fit2 led to a severe cardiomyopathy characterised by the failure of cardiomyocytes to develop as a functional syncytium and loss of synchrony between cardiomyocytes. A null allele of Fit1 was generated but this had no impact on the heart. Similarly, the silencing of Fit2 failed to affect heart function. In contrast, the silencing of Fit2 in the cardiomyocytes of Fit1 null flies disrupted syncytium development, leading to severe cardiomyopathy. The data definitively demonstrate a role for Fermitins in the development of a functional cardiac syncytium in Drosophila. The findings also show that the Fermitins can functionally compensate for each other in order to control syncytium development. These findings support the concept that abnormalities in cardiomyocyte KIND2 expression or function may contribute to cardiomyopathies in humans. PMID:23690969

  11. Activated ovarian endothelial cells promote early follicular development and survival.

    PubMed

    Kedem, Alon; Aelion-Brauer, Anate; Guo, Peipei; Wen, Duancheng; Ding, Bi-Sen; Lis, Raphael; Cheng, Du; Sandler, Vladislav M; Rafii, Shahin; Rosenwaks, Zev

    2017-09-19

    New data suggests that endothelial cells (ECs) elaborate essential "angiocrine factors". The aim of this study is to investigate the role of activated ovarian endothelial cells in early in-vitro follicular development. Mouse ovarian ECs were isolated using magnetic cell sorting or by FACS and cultured in serum free media. After a constitutive activation of the Akt pathway was initiated, early follicles (50-150 um) were mechanically isolated from 8-day-old mice and co-cultured with these activated ovarian endothelial cells (AOEC) (n = 32), gel (n = 24) or within matrigel (n = 27) in serum free media for 14 days. Follicular growth, survival and function were assessed. After 6 passages, flow cytometry showed 93% of cells grown in serum-free culture were VE-cadherin positive, CD-31 positive and CD 45 negative, matching the known EC profile. Beginning on day 4 of culture, we observed significantly higher follicular and oocyte growth rates in follicles co-cultured with AOECs compared with follicles on gel or matrigel. After 14 days of culture, 73% of primary follicles and 83% of secondary follicles co-cultured with AOEC survived, whereas the majority of follicles cultured on gel or matrigel underwent atresia. This is the first report of successful isolation and culture of ovarian ECs. We suggest that co-culture with activated ovarian ECs promotes early follicular development and survival. This model is a novel platform for the in vitro maturation of early follicles and for the future exploration of endothelial-follicular communication. In vitro development of early follicles necessitates a complex interplay of growth factors and signals required for development. Endothelial cells (ECs) may elaborate essential "angiocrine factors" involved in organ regeneration. We demonstrate that co-culture with ovarian ECs enables culture of primary and early secondary mouse ovarian follicles.

  12. BDNF regulates the translation of a select group of mRNAs by a mammalian target of rapamycin-phosphatidylinositol 3-kinase-dependent pathway during neuronal development.

    PubMed

    Schratt, Gerhard M; Nigh, Elizabeth A; Chen, Wen G; Hu, Linda; Greenberg, Michael E

    2004-08-18

    Local regulation of mRNA translation plays an important role in axon guidance, synaptic development, and neuronal plasticity. Little is known, however, regarding the mechanisms that control translation in neurons, and only a few mRNAs have been identified that are locally translated within axon and dendrites. Using Affymetrix gene arrays to identify mRNAs that are newly associated with polysomes after exposure to BDNF, we identified subsets of mRNAs for which translation is enhanced in neurons at different developmental stages. In mature neurons, many of these mRNAs encode proteins that are known to function at synapses, including CamKIIalpha, NMDA receptor subunits, and the postsynaptic density (PSD) scaffolding protein Homer2. BDNF regulates the translation of Homer2 locally in the synaptodendritic compartment by activating translational initiation via a mammalian target of rapamycin-phosphatidylinositol 3-kinase-dependent pathway. These findings suggest that BDNF likely regulates synaptic function by inducing the local synthesis of numerous synaptic proteins. The local translation of the cytoskeleton-associated protein Homer2 in particular might have important implications for growth cone dynamics and dendritic spine development.

  13. Early development of synchrony in cortical activations in the human.

    PubMed

    Koolen, N; Dereymaeker, A; Räsänen, O; Jansen, K; Vervisch, J; Matic, V; Naulaers, G; De Vos, M; Van Huffel, S; Vanhatalo, S

    2016-05-13

    Early intermittent cortical activity is thought to play a crucial role in the growth of neuronal network development, and large scale brain networks are known to provide the basis for higher brain functions. Yet, the early development of the large scale synchrony in cortical activations is unknown. Here, we tested the hypothesis that the early intermittent cortical activations seen in the human scalp EEG show a clear developmental course during the last trimester of pregnancy, the period of intensive growth of cortico-cortical connections. We recorded scalp EEG from altogether 22 premature infants at post-menstrual age between 30 and 44 weeks, and the early cortical synchrony was quantified using recently introduced activation synchrony index (ASI). The developmental correlations of ASI were computed for individual EEG signals as well as anatomically and mathematically defined spatial subgroups. We report two main findings. First, we observed a robust and statistically significant increase in ASI in all cortical areas. Second, there were significant spatial gradients in the synchrony in fronto-occipital and left-to-right directions. These findings provide evidence that early cortical activity is increasingly synchronized across the neocortex. The ASI-based metrics introduced in our work allow direct translational comparison to in vivo animal models, as well as hold promise for implementation as a functional developmental biomarker in future research on human neonates. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Regulation of early Xenopus development by ErbB signaling

    PubMed Central

    Nie, Shuyi; Chang, Chenbei

    2008-01-01

    ErbB signaling has long been implicated in cancer formation and progression and is shown to regulate cell division, migration and death during tumorigenesis. The functions of the ErbB pathway during early vertebrate embryogenesis, however, are not well understood. Here we report characterization of ErbB activities during early frog development. Gain-of-function analyses show that EGFR, ErbB2 and ErbB4 induce ectopic tumor-like cell mass that contains increased numbers of mitotic cells. Both the muscle and the neural markers are expressed in these ectopic protrusions. ErbBs also induce mesodermal markers in ectodermal explants. Loss-of-function studies using carboxyl terminal-truncated dominant-negative ErbB receptors demonstrate that blocking ErbB signals leads to defective gastrulation movements and malformation of the embryonic axis with a reduction in the head structures in early frog embryos. These data, together with the observation that ErbBs are expressed early during frog embryogenesis, suggest that ErbBs regulate cell proliferation, movements and embryonic patterning during early Xenopus development. PMID:16258939

  15. Family Concepts in Early Learning and Development Standards

    ERIC Educational Resources Information Center

    Walsh, Bridget A.; Sanchez, Claudia; Lee, Angela M.; Casillas, Nicole; Hansen, Caitlynn

    2016-01-01

    This exploratory study investigated the use of concepts related to families, parents, and the home in 51 state-level early learning and development standards documents. Guidelines from six national family involvement, engagement, and school-partnership models were used to create the Family Involvement Models Analysis Chart (FIMAC), which served as…

  16. Regionalism and Development in Early Nineteenth Century Spanish America.

    ERIC Educational Resources Information Center

    Friedman, Douglas

    An understanding of regionalism in early 19th century Spanish America is crucial to any understanding of this region's economic development. Regionalism became the barrier to the kind of integrated national economy that some writers claim could have been implemented had it not been for the imposition of dependency by external forces. This…

  17. Starting Smart: How Early Experiences Affect Brain Development. Second Edition.

    ERIC Educational Resources Information Center

    Hawley, Theresa

    Based on recent research, it is now believed that brain growth is highly dependent upon children's early experiences. Neurons allow communication and coordinated functioning among various brain areas. Brain development after birth consists of an ongoing process of wiring and rewiring the connections among neurons. The forming and breaking of…

  18. Applying cognitive training to target executive functions during early development.

    PubMed

    Wass, Sam V

    2015-01-01

    Developmental psychopathology is increasingly recognizing the importance of distinguishing causal processes (i.e., the mechanisms that cause a disease) from developmental outcomes (i.e., the symptoms of the disorder as it is eventually diagnosed). Targeting causal processes early in disordered development may be more effective than waiting until outcomes are established and then trying to reverse the pathogenic process. In this review, I evaluate evidence suggesting that neural and behavioral plasticity may be greatest at very early stages of development. I also describe correlational evidence suggesting that, across a number of conditions, early emerging individual differences in attentional control and working memory may play a role in mediating later-developing differences in academic and other forms of learning. I review the currently small number of studies that applied direct and indirect cognitive training targeted at young individuals and discuss methodological challenges associated with targeting this age group. I also discuss a number of ways in which early, targeted cognitive training may be used to help us understand the developmental mechanisms subserving typical and atypical cognitive development.

  19. The Ecology of Early Reading Development for Children in Poverty

    ERIC Educational Resources Information Center

    Kainz, Kirsten; Vernon-Feagans, Lynne

    2007-01-01

    In this study we investigated reading development from kindergarten to third grade for 1,913 economically disadvantaged children from the Early Childhood Longitudinal Study-Kindergarten Cohort. Characteristics of the child, the family, classroom instruction, and school composition were used to model influences from multiple levels of children's…

  20. Rethinking Early Learning and Development Standards in the Ugandan Context

    ERIC Educational Resources Information Center

    Ejuu, Godfrey

    2013-01-01

    Concerns that the African child is being tailored to be a "global child," alongside other homogenizing and dominating projections, such as early learning and development standards (ELDS), have increased. African communities need to be assured that global standards and global indicators will not further homogenize nations and thereby risk…

  1. Changing the Perspective on Early Development of Rett Syndrome

    ERIC Educational Resources Information Center

    Marschik, Peter B.; Kaufmann, Walter E.; Sigafoos, Jeff; Wolin, Thomas; Zhang, Dajie; Bartl-Pokorny, Katrin D.; Pini, Giorgio; Zappella, Michele; Tager-Flusberg, Helen; Einspieler, Christa; Johnston, Michael V.

    2013-01-01

    We delineated the achievement of early speech-language milestones in 15 young children with Rett syndrome ("MECP2" positive) in the first two years of life using retrospective video analysis. By contrast to the commonly accepted concept that these children are normal in the pre-regression period, we found markedly atypical development of…

  2. Model of Early Support of Child Development in Poland

    ERIC Educational Resources Information Center

    Czyz, Anna Katarzyna

    2018-01-01

    The development of a child, especially a child with a disability, is conditional upon the initiation of rehabilitation measures immediately after the problem has been identified. The quality of the reaction is conditioned by the functioning of the therapeutic team. The main purpose of the research was the diagnosis of early support system for…

  3. Identification of the Social Development in Early Childhood in Pakistan

    ERIC Educational Resources Information Center

    Malik, Asif; Sarwar, Muhammad; Khan, Naeemullah

    2010-01-01

    This study was conducted to identify the social development in early childhood years. It was delimited to eight private schools of Lahore City from the area of Faisal Town and Shadman. Forty students (male and female) were randomly selected as the sample. Five students from Nursery, Prep and grade one were selected from each school. A checklist…

  4. The Use of Electrophysiology in the Study of Early Development

    ERIC Educational Resources Information Center

    Szucs, Denes

    2005-01-01

    Electrophysiology is a timely and important tool in the study of early cognitive development. This commentary polishes the definition of event-related potential (ERP) components; often interpreted as expressions of mental processes. Further, attention is drawn to time-frequency analysis of the electroencephalogram (EEG) which conveys much more…

  5. Development of the Life Story in Early Adolescence

    ERIC Educational Resources Information Center

    Steiner, Kristina L.; Pillemer, David B.

    2018-01-01

    Life span developmental psychology proposes that the ability to create a coherent life narrative does not develop until early adolescence. Using a novel methodology, 10-, 12-, and 14-year-old participants were asked to tell their life stories aloud to a researcher. Later, participants separated their transcribed narratives into self-identified…

  6. MAMMARY GLAND DEVELOPMENT: EARLY LIFE EFFECTS FROM THE ENVIRONMENT

    EPA Science Inventory

    Mammary Gland Development: Early Life Effects from the Environment

    S.E. Fenton. Reproductive Toxicology Division, National Health and Environmental Effects Laboratory, ORD, U.S. EPA, Research Triangle Park, NC 27711.

    As signs of precocious puberty in girls reach ...

  7. Predictors of Early versus Later Spelling Development in Danish

    ERIC Educational Resources Information Center

    Nielsen, Anne-Mette Veber; Juul, Holger

    2016-01-01

    The present study examined phoneme awareness, phonological short term memory, letter knowledge, rapid automatized naming (RAN), and visual-verbal paired associate learning (PAL) as longitudinal predictors of spelling skills in an early phase (Grade 2) and a later phase (Grade 5) of development in a sample of 140 children learning to spell in the…

  8. Career Planning and Development for Early-Career Scientists

    EPA Science Inventory

    Early career development can be looked at as being of two major phases. The first phase is the formal educational process leading to an awarded degree, postdoctoral training, and potentially formal certification in a scientific discipline. The second phase is the informal educa...

  9. Early Intervention and Its Effects on Maternal and Child Development.

    ERIC Educational Resources Information Center

    Slaughter, Diana T.

    1983-01-01

    The longitudinal study reported used an intervention strategy to test the thesis that sociocultural background, mediated by maternal attitudes and behaviors, influences Black children's early development in educationally significant ways. Two models of parent education were contrasted: the Levenstein toy demonstration program and the…

  10. Developing Early Undergraduate Research at a Two-Year College

    ERIC Educational Resources Information Center

    Sibbernsen, Kendra

    2013-01-01

    Two-year college (TYC) physics teachers are not often required to provide student research experiences as a part of their contracted duties. However, some TYC physics faculty members are interested in developing research opportunities for their freshman- and sophomore-level students, often called "early undergraduate research" (EUR).…

  11. Applying cognitive training to target executive functions during early development

    PubMed Central

    Wass, Sam V.

    2015-01-01

    Developmental psychopathology is increasingly recognizing the importance of distinguishing causal processes (i.e., the mechanisms that cause a disease) from developmental outcomes (i.e., the symptoms of the disorder as it is eventually diagnosed). Targeting causal processes early in disordered development may be more effective than waiting until outcomes are established and then trying to reverse the pathogenic process. In this review, I evaluate evidence suggesting that neural and behavioral plasticity may be greatest at very early stages of development. I also describe correlational evidence suggesting that, across a number of conditions, early emerging individual differences in attentional control and working memory may play a role in mediating later-developing differences in academic and other forms of learning. I review the currently small number of studies that applied direct and indirect cognitive training targeted at young individuals and discuss methodological challenges associated with targeting this age group. I also discuss a number of ways in which early, targeted cognitive training may be used to help us understand the developmental mechanisms subserving typical and atypical cognitive development. PMID:24511910

  12. Guidelines for Making a Video Presentation on Early Development.

    ERIC Educational Resources Information Center

    Cooper, Carolyn S.; And Others

    This paper discusses the production of videotape recordings illustrating developmental milestones of early childhood to serve as a reference point in working with parents or staff caring for young children who have disabilities. Procedures for making a video presentation include the following steps: select a topic (such as motor development,…

  13. Approaches to Developing Health in Early Years Settings

    ERIC Educational Resources Information Center

    Mooney, Ann; Boddy, Janet; Statham, June; Warwick, Ian

    2008-01-01

    Purpose: The purpose of the paper is to consider the opportunities and difficulties in developing health-promotion work in early years settings in the UK. Design/methodology/approach: As the first study of its kind conducted in the UK, a multi-method approach was adopted involving: an overview of health-related guidance and of effective…

  14. Formative Evaluation of the Early Development Instrument: Progress and Prospects

    ERIC Educational Resources Information Center

    Keating, Daniel P.

    2007-01-01

    This article is a commentary for the special issue on the Early Development Instrument (EDI), a community tool to assess children's school readiness and developmental outcomes at a group level. The EDI is administered by kindergarten teachers, who assess their kindergarten students on 5 developmental domains: physical health and well-being, social…

  15. State Guide to Developing Successful Early Childhood Data Systems

    ERIC Educational Resources Information Center

    ICF International (NJ1), 2012

    2012-01-01

    Early education leaders--inside and outside of government--are looking for new ways to improve quality, accountability, and efficiency across many different programs serving young children and their families, and they see investment in data systems as a pivotal part of that effort. However, it can be challenging to develop and implement effective…

  16. Towards Sustainable National Development through Well Managed Early Childhood Education

    ERIC Educational Resources Information Center

    Abraham, Nath M.

    2012-01-01

    This paper discusses issues relating to sustainable development and effective management of early childhood education. The child is the "owner" of the future. The problems that confront the current generation are complex and serious that cannot be addressed in the same way they were created. But they can be addressed. The concept of…

  17. More Alike than Different: Early Childhood Professional Development in Guatemala

    ERIC Educational Resources Information Center

    Hardin, Belinda J.; Vardell, Rosemarie; de Castaneda, Albertina

    2008-01-01

    This article describes an early childhood professional development project that took place in the summer of 2005 in Guatemala City. Located in Central America, Guatemala has a population of approximately 12.3 million people, including more than two million children under the age of 5 (UNESCO Institute for Statistics, 2007; UNICEF, 2004). Events…

  18. Black Female Faculty Success and Early Career Professional Development

    ERIC Educational Resources Information Center

    Jones, Tamara Bertrand; Osborne-Lampkin, La'Tara

    2013-01-01

    In recent years, a number of Black female junior scholars have participated in an early career professional development program designed to address socialization issues through individual and small group mentoring. This descriptive qualitative study investigated scholars' perceptions of the importance and effectiveness of a research…

  19. HIV Infection: Transmission, Effects on Early Development, and Interventions.

    ERIC Educational Resources Information Center

    Lowenthal, Barbara

    1997-01-01

    Describes the modes of transmission of HIV and the course of the disease in infants and toddlers. Information is provided on its effects on early development, medical screening and treatments, therapies, psychosocial assistance, and interventions, including nutritional therapy, occupational and physical therapies, and speech and language therapy.…

  20. Cholinergic Mechanisms, Early Brain Development, and Risk for Schizophrenia

    PubMed Central

    Ross, Randal G; Stevens, Karen E; Proctor, William R; Leonard, Sherry; Kisley, Michael A; Hunter, Sharon K; Freedman, Robert; Adams, Catherine E

    2009-01-01

    Neuropsychiatric diseases are complex illnesses where the onset of diagnostic symptomology is often the end result of a decades-long process of aberrant brain development. The identification of novel treatment strategies aimed at normalizing early brain development and preventing mental illness should be a major therapeutic goal; however, there are few models for how this goal might be achieved. This report uses the attentional deficits of schizophrenia as an example and reviews data from genetic, anatomical, physiological, and pharmacologic studies to hypothesize a developmental model with translational primary prevention implications. Specifically, the model suggests that an early interaction between α7 nicotinic receptor density and choline availability may contribute to the development of schizophrenia-associated attentional deficits. Translational implications, including perinatal dietary choline supplementation, are discussed. It is hoped that presentation of this model will stimulate other efforts to develop empirically-driven primary prevention strategies. PMID:19925602

  1. Developing International Collaborations for Early Career Researchers in Psychology

    PubMed Central

    Flanagan, Julianne C.; Barrett, Emma L.; Crome, Erica; Forbes, Miriam

    2015-01-01

    International collaboration is becoming increasingly vital as the emphasis on unmet need for mental health across cultures and nations grows. Opportunities exist for early career researchers to engage in international collaboration. However, little information is provided about such opportunities in most current psychology training models. The authors are early career researchers in psychology from U.S. and Australia who have developed a collaborative relationship over the past two years. Our goal is to increase awareness of funding opportunities to support international research and to highlight the benefits and challenges associated with international collaboration based on our experience. PMID:27453624

  2. Early development of Xenopus embryos is affected by simulated gravity

    NASA Technical Reports Server (NTRS)

    Yokota, Hiroki; Neff, Anton W.; Malacinski, George M.

    1994-01-01

    Early amphibian (Xenopus laevis) development under clinostat-simulated weightlessness and centrifuge-simulated hypergravity was studied. The results revealed significant effects on (i) 'morphological patterning' such as the cleavage furrow pattern in the vegetal hemisphere at the eight-cell stage and the shape of the dorsal lip in early gastrulae and (ii) 'the timing of embryonic events' such as the third cleavage furrow completion and the dorsal lip appearance. Substantial variations in sensitivity to simulated force fields were observed, which should be considered in interpreting spaceflight data.

  3. On the role of germ cells in mammalian gonad development: quiet passengers or back-seat drivers?

    PubMed

    Rios-Rojas, Clarissa; Bowles, Josephine; Koopman, Peter

    2015-04-01

    In addition to their role as endocrine organs, the gonads nurture and protect germ cells, and regulate the formation of gametes competent to convey the genome to the following generation. After sex determination, gonadal somatic cells use several known signalling pathways to direct germ cell development. However, the extent to which germ cells communicate back to the soma, the molecular signals they use to do so and the significance of any such signalling remain as open questions. Herein, we review findings arising from the study of gonadal development and function in the absence of germ cells in a range of organisms. Most published studies support the view that germ cells are unimportant for foetal gonadal development in mammals, but later become critical for stabilisation of gonadal function and somatic cell phenotype. However, the lack of consistency in the data, and clear differences between mammals and other vertebrates and invertebrates, suggests that the story may not be so simple and would benefit from more careful analysis using contemporary molecular, cell biology and imaging tools. © 2015 Society for Reproduction and Fertility.

  4. Effects of early life stress on amygdala and striatal development

    PubMed Central

    Fareri, Dominic S.; Tottenham, Nim

    2016-01-01

    Species-expected caregiving early in life is critical for the normative development and regulation of emotional behavior, the ability to effectively evaluate affective stimuli in the environment, and the ability to sustain social relationships. Severe psychosocial stressors early in life (early life stress; ELS) in the form of the absence of species expected caregiving (i.e., caregiver deprivation), can drastically impact one’s social and emotional success, leading to the onset of internalizing illness later in life. Development of the amygdala and striatum, two key regions supporting affective valuation and learning, is significantly affected by ELS, and their altered developmental trajectories have important implications for cognitive, behavioral and socioemotional development. However, an understanding of the impact of ELS on the development of functional interactions between these regions and subsequent behavioral effects is lacking. In this review, we highlight the roles of the amygdala and striatum in affective valuation and learning in maturity and across development. We discuss their function separately as well as their interaction. We highlight evidence across species characterizing how ELS induced changes in the development of the amygdala and striatum mediate subsequent behavioral changes associated with internalizing illness, positing a particular import of the effect of ELS on their interaction. PMID:27174149

  5. Effects of early life stress on amygdala and striatal development.

    PubMed

    Fareri, Dominic S; Tottenham, Nim

    2016-06-01

    Species-expected caregiving early in life is critical for the normative development and regulation of emotional behavior, the ability to effectively evaluate affective stimuli in the environment, and the ability to sustain social relationships. Severe psychosocial stressors early in life (early life stress; ELS) in the form of the absence of species expected caregiving (i.e., caregiver deprivation), can drastically impact one's social and emotional success, leading to the onset of internalizing illness later in life. Development of the amygdala and striatum, two key regions supporting affective valuation and learning, is significantly affected by ELS, and their altered developmental trajectories have important implications for cognitive, behavioral and socioemotional development. However, an understanding of the impact of ELS on the development of functional interactions between these regions and subsequent behavioral effects is lacking. In this review, we highlight the roles of the amygdala and striatum in affective valuation and learning in maturity and across development. We discuss their function separately as well as their interaction. We highlight evidence across species characterizing how ELS induced changes in the development of the amygdala and striatum mediate subsequent behavioral changes associated with internalizing illness, positing a particular import of the effect of ELS on their interaction. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Fathers' sensitive parenting and the development of early executive functioning.

    PubMed

    Towe-Goodman, Nissa R; Willoughby, Michael; Blair, Clancy; Gustafsson, Hanna C; Mills-Koonce, W Roger; Cox, Martha J

    2014-12-01

    Using data from a diverse sample of 620 families residing in rural, predominately low-income communities, this study examined longitudinal links between fathers' sensitive parenting in infancy and toddlerhood and children's early executive functioning, as well as the contribution of maternal sensitive parenting. After accounting for the quality of concurrent and prior parental care, children's early cognitive ability, and other child and family factors, fathers' and mothers' sensitive and supportive parenting during play at 24 months predicted children's executive functioning at 3 years of age. In contrast, paternal parenting quality during play at 7 months did not make an independent contribution above that of maternal care, but the links between maternal sensitive and supportive parenting and executive functioning seemed to operate in similar ways during infancy and toddlerhood. These findings add to prior work on early experience and children's executive functioning, suggesting that both fathers and mothers play a distinct and complementary role in the development of these self-regulatory skills.

  7. Three-dimensional analysis of nuclear heterochromatin distribution during early development in the rabbit.

    PubMed

    Bonnet-Garnier, Amélie; Kiêu, Kiên; Aguirre-Lavin, Tiphaine; Tar, Krisztina; Flores, Pierre; Liu, Zichuan; Peynot, Nathalie; Chebrout, Martine; Dinnyés, András; Duranthon, Véronique; Beaujean, Nathalie

    2018-04-18

    Changes to the spatial organization of specific chromatin domains such as constitutive heterochromatin have been studied extensively in somatic cells. During early embryonic development, drastic epigenetic reprogramming of both the maternal and paternal genomes, followed by chromatin remodeling at the time of embryonic genome activation (EGA), have been observed in the mouse. Very few studies have been performed in other mammalian species (human, bovine, or rabbit) and the data are far from complete. During this work, we studied the three-dimensional organization of pericentromeric regions during the preimplantation period in the rabbit using specific techniques (3D-FISH) and tools (semi-automated image analysis). We observed that the pericentromeric regions (identified with specific probes for Rsat I and Rsat II genomic sequences) changed their shapes (from pearl necklaces to clusters), their nuclear localizations (from central to peripheral), as from the 4-cell stage. This reorganization goes along with histone modification changes and reduced amount of interactions with nucleolar precursor body surface. Altogether, our results suggest that the 4-cell stage may be a crucial window for events necessary before major EGA, which occurs during the 8-cell stage in the rabbit.

  8. Hepatocyte Growth Factor-c-MET Signaling Mediates the Development of Nonsensory Structures of the Mammalian Cochlea and Hearing.

    PubMed

    Shibata, Shumei; Miwa, Toru; Wu, Hsiao-Huei; Levitt, Pat; Ohyama, Takahiro

    2016-08-03

    The stria vascularis is a nonsensory structure that is essential for auditory hair cell function by maintaining potassium concentration of the scala media. During mouse embryonic development, a subpopulation of neural crest cell-derived melanocytes migrates and incorporates into a subregion of the cochlear epithelium, forming the intermediate cell layer of the stria vascularis. The relation of this developmental process to stria vascularis function is currently unknown. In characterizing the molecular differentiation of developing peripheral auditory structures, we discovered that hepatocyte growth factor (Hgf) is expressed in the future stria vascularis of the cochlear epithelium. Its receptor tyrosine kinase, c-Met, is expressed in the cochlear epithelium and melanocyte-derived intermediate cells in the stria vascularis. Genetic dissection of HGF signaling via c-MET reveals that the incorporation of the melanocytes into the future stria vascularis of the cochlear duct requires c-MET signaling. In addition, inactivation of either the ligand or receptor developmentally resulted in a profound hearing loss at young adult stages. These results suggest a novel connection between HGF signaling and deafness via melanocyte deficiencies. We found the roles of hepatocyte growth factor (HGF) signaling in stria vascularis development for the first time and that lack of HGF signaling in the inner ear leads to profound hearing loss in the mouse. Our findings reveal a novel mechanism that may underlie human deafness DFNB39 and DFNB97. Our findings reveal an additional example of context-dependent c-MET signaling diversity, required here for proper cellular invasion developmentally that is essential for specific aspects of auditory-related organogenesis. Copyright © 2016 the authors 0270-6474/16/368200-10$15.00/0.

  9. Hepatocyte Growth Factor–c-MET Signaling Mediates the Development of Nonsensory Structures of the Mammalian Cochlea and Hearing

    PubMed Central

    Shibata, Shumei; Miwa, Toru; Wu, Hsiao-Huei; Levitt, Pat

    2016-01-01

    The stria vascularis is a nonsensory structure that is essential for auditory hair cell function by maintaining potassium concentration of the scala media. During mouse embryonic development, a subpopulation of neural crest cell-derived melanocytes migrates and incorporates into a subregion of the cochlear epithelium, forming the intermediate cell layer of the stria vascularis. The relation of this developmental process to stria vascularis function is currently unknown. In characterizing the molecular differentiation of developing peripheral auditory structures, we discovered that hepatocyte growth factor (Hgf) is expressed in the future stria vascularis of the cochlear epithelium. Its receptor tyrosine kinase, c-Met, is expressed in the cochlear epithelium and melanocyte-derived intermediate cells in the stria vascularis. Genetic dissection of HGF signaling via c-MET reveals that the incorporation of the melanocytes into the future stria vascularis of the cochlear duct requires c-MET signaling. In addition, inactivation of either the ligand or receptor developmentally resulted in a profound hearing loss at young adult stages. These results suggest a novel connection between HGF signaling and deafness via melanocyte deficiencies. SIGNIFICANCE STATEMENT We found the roles of hepatocyte growth factor (HGF) signaling in stria vascularis development for the first time and that lack of HGF signaling in the inner ear leads to profound hearing loss in the mouse. Our findings reveal a novel mechanism that may underlie human deafness DFNB39 and DFNB97. Our findings reveal an additional example of context-dependent c-MET signaling diversity, required here for proper cellular invasion developmentally that is essential for specific aspects of auditory-related organogenesis. PMID:27488639

  10. Development of a new screening assay to identify proteratogenic substances using zebrafish danio rerio embryo combined with an exogenous mammalian metabolic activation system (mDarT).

    PubMed

    Busquet, François; Nagel, Roland; von Landenberg, Friedrich; Mueller, Stefan O; Huebler, Nicole; Broschard, Thomas H

    2008-07-01

    The assessment of teratogenic effects of chemicals is generally performed using in vivo teratogenicity assays, for example, in rats or rabbits. We have developed an in vitro teratogenicity assay using the zebrafish Danio rerio embryo combined with an exogenous mammalian metabolic activation system (MAS), able to biotransform proteratogenic compounds. Cyclophosphamide (CPA) and ethanol were used as proteratogens to test the efficiency of this assay. Briefly, the zebrafish embryos were cocultured at 2 hpf (hours postfertilization) with the test material at varying concentrations, induced male rat liver microsomes and nicotinamide adenine dinucleotide phosphate (reduced) for 60 min at 32 degrees C under moderate agitation in Tris-buffer. The negative control (test material alone) and the MAS control (MAS alone) were incubated in parallel. For each test group, 20 eggs were used for statistical robustness. Afterward fish embryos were transferred individually into 24-well plates filled with fish medium for 48 h at 26 degrees C with a 12-h light cycle. Teratogenicity was scored after 24 and 48 hpf using morphological endpoints. No teratogenic effects were observed in fish embryos exposed to the proteratogens alone, that is, without metabolic activation. In contrast, CPA and ethanol induced abnormalities in fish embryos when coincubated with microsomes. The severity of malformations increased with increasing concentrations of the proteratogens. We conclude that the application of microsomes will improve and refine the D. rerio teratogenicity assay as a predictive and valuable alternative method to screen teratogenic substances.

  11. Non-muscle myosin IIB (Myh10) is required for epicardial function and coronary vessel formation during mammalian development

    PubMed Central

    Mitchell, Karen; Al-Anbaki, Ali; Shaikh Qureshi, Wasay Mohiuddin; Tenin, Gennadiy; Lu, Yinhui; Clowes, Christopher; Robertson, Abigail; Barnes, Emma; Wright, Jayne A.; Keavney, Bernard; Lovell, Simon C.

    2017-01-01

    The coronary vasculature is an essential vessel network providing the blood supply to the heart. Disruptions in coronary blood flow contribute to cardiac disease, a major cause of premature death worldwide. The generation of treatments for cardiovascular disease will be aided by a deeper understanding of the developmental processes that underpin coronary vessel formation. From an ENU mutagenesis screen, we have isolated a mouse mutant displaying embryonic hydrocephalus and cardiac defects (EHC). Positional cloning and candidate gene analysis revealed that the EHC phenotype results from a point mutation in a splice donor site of the Myh10 gene, which encodes NMHC IIB. Complementation testing confirmed that the Myh10 mutation causes the EHC phenotype. Characterisation of the EHC cardiac defects revealed abnormalities in myocardial development, consistent with observations from previously generated NMHC IIB null mouse lines. Analysis of the EHC mutant hearts also identified defects in the formation of the coronary vasculature. We attribute the coronary vessel abnormalities to defective epicardial cell function, as the EHC epicardium displays an abnormal cell morphology, reduced capacity to undergo epithelial-mesenchymal transition (EMT), and impaired migration of epicardial-derived cells (EPDCs) into the myocardium. Our studies on the EHC mutant demonstrate a requirement for NMHC IIB in epicardial function and coronary vessel formation, highlighting the importance of this protein in cardiac development and ultimately, embryonic survival. PMID:29084269

  12. Early development of physical aggression and early risk factors for chronic physical aggression in humans.

    PubMed

    Tremblay, Richard E

    2014-01-01

    This chapter describes the state of knowledge on the development of physical aggression from early childhood to adulthood, the long term outcomes of chronic physical aggression during childhood and the risk factors for chronic physical aggression. Unraveling the development of physical aggression is important to understand when and why humans start using physical aggression, to understand why some humans suffer from chronic physical aggression and to understand how to prevent the development of this disorder which causes much distress to the aggressors and their victims. The study of the developmental origins of aggression also sheds light on the reasons why situational prevention of aggression is important at all ages and in all cultures.

  13. Alternatives to the fish early life-stage test: Developing a conceptual model for early fish development

    EPA Science Inventory

    Chronic fish toxicity is a key parameter for hazard classification and environmental risk assessment of chemicals, and the OECD 210 fish early life-stage (FELS) test is the primary guideline test used for various international regulatory programs. There exists a need to develop ...

  14. Gross Motor Development, Movement Abnormalities, and Early Identification of Autism

    PubMed Central

    Young, Gregory S.; Goldring, Stacy; Greiss-Hess, Laura; Herrera, Adriana M.; Steele, Joel; Macari, Suzanne; Hepburn, Susan; Rogers, Sally J.

    2015-01-01

    Gross motor development (supine, prone, rolling, sitting, crawling, walking) and movement abnormalities were examined in the home videos of infants later diagnosed with autism (regression and no regression subgroups), developmental delays (DD), or typical development. Group differences in maturity were found for walking, prone, and supine, with the DD and Autism-No Regression groups both showing later developing motor maturity than typical children. The only statistically significant differences in movement abnormalities were in the DD group; the two autism groups did not differ from the typical group in rates of movement abnormalities or lack of protective responses. These findings do not replicate previous investigations suggesting that early motor abnormalities seen on home video can assist in early identification of autism. PMID:17805956

  15. Early stress and human behavioral development: emerging evolutionary perspectives.

    PubMed

    Del Giudice, M

    2014-08-01

    Stress experienced early in life exerts a powerful, lasting influence on development. Converging empirical findings show that stressful experiences become deeply embedded in the child's neurobiology, with an astonishing range of long-term effects on cognition, emotion, and behavior. In contrast with the prevailing view that such effects are the maladaptive outcomes of 'toxic' stress, adaptive models regard them as manifestations of evolved developmental plasticity. In this paper, I offer a brief introduction to adaptive models of early stress and human behavioral development, with emphasis on recent theoretical contributions and emerging concepts in the field. I begin by contrasting dysregulation models of early stress with their adaptive counterparts; I then introduce life history theory as a unifying framework, and review recent work on predictive adaptive responses (PARs) in human life history development. In particular, I discuss the distinction between forecasting the future state of the environment (external prediction) and forecasting the future state of the organism (internal prediction). Next, I present the adaptive calibration model, an integrative model of individual differences in stress responsivity based on life history concepts. I conclude by examining how maternal-fetal conflict may shape the physiology of prenatal stress and its adaptive and maladaptive effects on postnatal development. In total, I aim to show how theoretical work from evolutionary biology is reshaping the way we think about the role of stress in human development, and provide researchers with an up-to-date conceptual map of this fascinating and rapidly evolving field.

  16. Recent advances in the development and function of type II spiral ganglion neurons in the mammalian inner ear

    PubMed Central

    Zhang, Kaidi D.; Coate, Thomas M.

    2016-01-01

    In hearing, mechanically sensitive hair cells (HCs) in the cochlea release glutamate onto spiral ganglion neurons (SGNs) to relay auditory information to the central nervous system (CNS). There are two main SGN subtypes, which differ in morphology, number, synaptic targets, innervation patterns and firing properties. About 90-95% of SGNs are the type I SGNs, which make a single bouton connection with inner hair cells (IHCs) and have been well described in the canonical auditory pathway for sound detection. However, less attention has been given to the type II SGNs, which exclusively innervate outer hair cells (OHCs). In this review, we emphasize recent advances in the molecular mechanisms that control how type II SGNs develop and form connections with OHCs, and exciting new insights into the function of type II SGNs. PMID:27760385

  17. BMP-Mediated Functional Cooperation between Dlx5;Dlx6 and Msx1;Msx2 during Mammalian Limb Development

    PubMed Central

    Vieux-Rochas, Maxence; Bouhali, Kamal; Mantero, Stefano; Garaffo, Giulia; Provero, Paolo; Astigiano, Simonetta; Barbieri, Ottavia; Caratozzolo, Mariano F.; Tullo, Apollonia; Guerrini, Luisa; Lallemand, Yvan; Robert, Benoît

    2013-01-01

    The Dlx and Msx homeodomain transcription factors play important roles in the control of limb development. The combined disruption of Msx1 and Msx2, as well as that of Dlx5 and Dlx6, lead to limb patterning defects with anomalies in digit number and shape. Msx1;Msx2 double mutants are characterized by the loss of derivatives of the anterior limb mesoderm which is not observed in either of the simple mutants. Dlx5;Dlx6 double mutants exhibit hindlimb ectrodactyly. While the morphogenetic action of Msx genes seems to involve the BMP molecules, the mode of action of Dlx genes still remains elusive. Here, examining the limb phenotypes of combined Dlx and Msx mutants we reveal a new Dlx-Msx regulatory loop directly involving BMPs. In Msx1;Dlx5;Dlx6 triple mutant mice (TKO), beside the expected ectrodactyly, we also observe the hallmark morphological anomalies of Msx1;Msx2 double mutants suggesting an epistatic role of Dlx5 and Dlx6 over Msx2. In Msx2;Dlx5;Dlx6 TKO mice we only observe an aggravation of the ectrodactyly defect without changes in the number of the individual components of the limb. Using a combination of qPCR, ChIP and bioinformatic analyses, we identify two Dlx/Msx regulatory pathways: 1) in the anterior limb mesoderm a non-cell autonomous Msx-Dlx regulatory loop involves BMP molecules through the AER and 2) in AER cells and, at later stages, in the limb mesoderm the regulation of Msx2 by Dlx5 and Dlx6 occurs also cell autonomously. These data bring new elements to decipher the complex AER-mesoderm dialogue that takes place during limb development and provide clues to understanding the etiology of congenital limb malformations. PMID:23382810

  18. BMP-mediated functional cooperation between Dlx5;Dlx6 and Msx1;Msx2 during mammalian limb development.

    PubMed

    Vieux-Rochas, Maxence; Bouhali, Kamal; Mantero, Stefano; Garaffo, Giulia; Provero, Paolo; Astigiano, Simonetta; Barbieri, Ottavia; Caratozzolo, Mariano F; Tullo, Apollonia; Guerrini, Luisa; Lallemand, Yvan; Robert, Benoît; Levi, Giovanni; Merlo, Giorgio R

    2013-01-01

    The Dlx and Msx homeodomain transcription factors play important roles in the control of limb development. The combined disruption of Msx1 and Msx2, as well as that of Dlx5 and Dlx6, lead to limb patterning defects with anomalies in digit number and shape. Msx1;Msx2 double mutants are characterized by the loss of derivatives of the anterior limb mesoderm which is not observed in either of the simple mutants. Dlx5;Dlx6 double mutants exhibit hindlimb ectrodactyly. While the morphogenetic action of Msx genes seems to involve the BMP molecules, the mode of action of Dlx genes still remains elusive. Here, examining the limb phenotypes of combined Dlx and Msx mutants we reveal a new Dlx-Msx regulatory loop directly involving BMPs. In Msx1;Dlx5;Dlx6 triple mutant mice (TKO), beside the expected ectrodactyly, we also observe the hallmark morphological anomalies of Msx1;Msx2 double mutants suggesting an epistatic role of Dlx5 and Dlx6 over Msx2. In Msx2;Dlx5;Dlx6 TKO mice we only observe an aggravation of the ectrodactyly defect without changes in the number of the individual components of the limb. Using a combination of qPCR, ChIP and bioinformatic analyses, we identify two Dlx/Msx regulatory pathways: 1) in the anterior limb mesoderm a non-cell autonomous Msx-Dlx regulatory loop involves BMP molecules through the AER and 2) in AER cells and, at later stages, in the limb mesoderm the regulation of Msx2 by Dlx5 and Dlx6 occurs also cell autonomously. These data bring new elements to decipher the complex AER-mesoderm dialogue that takes place during limb development and provide clues to understanding the etiology of congenital limb malformations.

  19. Conditions on Early Mars Might Have Fostered Rapid and Early Development of Life

    NASA Technical Reports Server (NTRS)

    Gibson, Everett K.; McKay, David S.; Thomas-Keprta, Kathie L.; Clemett, Simon J.; Wentworth, Susan J.

    2007-01-01

    The exploration of Mars during the past decades has begun to unveil the history of the planet. The combinations of remote sensing, in situ geochemical compositional measurements and photographic observations from both above and on the surface have shown Mars to have a dynamic and active geologic evolution. Mars geologic evolution clearly had conditions that were suitable for supporting life. For a planet to be able to be habitable, it must have water, carbon sources, energy sources and a dynamic geologic past. Mars meets all of these requirements. The first 600 My of Martian history were ripe for life to develop because of the abundance of (i) Water-carved canyons and oceans or lakes with the early presence of near surface water shown by precipitated carbonates in ALH84001 well-dated at approx.3.9 Gy., (ii) Energy from the original accretional processes, a molten core which generated a strong magnetic field leaving a permanent record in the early crust, early active volcanism continuing throughout Martian history, and, and continuing impact processes, (iii) Carbon and water from possibly extensive volcanic outgassing (i.e. H2O, CO2, CH4, CO, O2, N2, H2S, SO2, etc.) and (iv) some crustal tectonics as revealed by faulting and possible plate movement reflected by the magnetic pattern in the crust. The question arises: "Why would life not evolve from these favorable conditions on early Mars in its first 600 My?" During this period, it seems likely that environmental near-surface conditions on Mars were more favorable to life than at any later time. Standing bodies of water, precipitation and flowing surface water, and possibly abundant hydrothermal energy would all favor the formation of early life. Even if life developed elsewhere (on Earth, Venus, or on other solar systems) and was transported to Mars, the surface conditions were likely very hospitable for that introduced life to multiply and evolve.

  20. Characteristics of effective professional development for early career science teachers

    NASA Astrophysics Data System (ADS)

    Simon, Shirley; Campbell, Sandra; Johnson, Sally; Stylianidou, Fani

    2011-04-01

    The research reported here set out to investigate the features in schools and science departments that were seen as effective in contributing to the continuing professional development (CPD) of early career science teachers. Ten schools took part in the study, selected on the basis of their reputation for having effective CPD practices. To gain different perspectives from within the organisations we conducted interviews with senior members of staff, heads of science departments and early career teachers. A thematic analysis of the interviews is presented, drawing on findings from across the 10 schools, and exemplified in more detail by a vignette to show specific features of effective CPD practice. The study has revealed a wealth of practice across the 10 schools, which included a focus on broadening experience beyond the classroom, having an open, sharing, non-threatening culture and systemic procedures for mentoring and support that involved ring-fenced budgets. The schools also deployed staff judiciously in critical roles that model practice and motivate early career science teachers. Early career teachers were concerned primarily with their overall development as teachers, though some science specific examples such as observing practical work and sessions to address subject knowledge were seen as important.

  1. Endosperm turgor pressure decreases during early Arabidopsis seed development.

    PubMed

    Beauzamy, Léna; Fourquin, Chloé; Dubrulle, Nelly; Boursiac, Yann; Boudaoud, Arezki; Ingram, Gwyneth

    2016-09-15

    In Arabidopsis, rapid expansion of the coenocytic endosperm after fertilisation has been proposed to drive early seed growth, which is in turn constrained by the seed coat. This hypothesis implies physical heterogeneity between the endosperm and seed coat compartments during early seed development, which to date has not been demonstrated. Here, we combine tissue indentation with modelling to show that the physical properties of the developing seed are consistent with the hypothesis that elevated endosperm-derived turgor pressure drives early seed expansion. We provide evidence that whole-seed turgor is generated by the endosperm at early developmental stages. Furthermore, we show that endosperm cellularisation and seed growth arrest are associated with a drop in endosperm turgor pressure. Finally, we demonstrate that this decrease is perturbed when the function of POLYCOMB REPRESSIVE COMPLEX 2 is lost, suggesting that turgor pressure changes could be a target of genomic imprinting. Our results indicate a developmental role for changes in endosperm turgor pressure in the Arabidopsis seed. © 2016. Published by The Company of Biologists Ltd.

  2. The early development and evolution of the human brain.

    PubMed

    Crawford, M A

    1990-01-01

    THE CHEMISTRY OF THE BRAIN: The brain and nervous system is characterised by a heavy investment in lipid chemistry which accounts for up to 60% of its structural material. In the different mammalian species so far studied, only the 20 and 22 carbon chain length polyenoic fatty acids were present and the balance of the n-3 to n-6 fatty acids was consistently 1:1. The difference observed between species, was not in the chemistry but in the extent to which the brain is developed. This paper discusses the possibility that essential fatty acids may have played a part in it evolution. THE ORIGIN OF AIR BREATHING ANIMALS: The first phase of the planet's existence indulged in high temperature reactions in which oxygen combined with everything feasible: from silicon to make rocks to hydrogen to make water. Once the planet's temperature dropped to a point at which water could condense on the surface allowing chemical reactions to take place in it. The atmosphere was at that time devoid of oxygen so life evolved in a reducing atmosphere. Oxygen was liberated by photolysis of water and as a by-product of the blue-green algae through photosynthesis. When the point was reached at which oxidative metabolism became thermodynamically possible, animal life evolved with all the principle phyla establishing themselves within a relatively short space of geological time. (Bernal 1973). DHA and nerve cell membranes DHA AND NERVE CELL MEMBRANES: From the chemistry of contemporary algae it is likely that animal life evolved in an n-3 rich environment although not exclusively so as smaller amounts of n-6 fatty acids would have been present. A key feature of the first animals was the evolution of the photoreceptor: in examples of marine, amphibian and modern mammalian species, it has been found to use docosahexaenoic acid (DHA) as the principle membrane fatty acid in the phosphoglycerides. It is likely that the first animals did so as well. Coincidentally, the synaptic membranes involved in

  3. Tubulointerstitial nephritis antigen: an extracellular matrix protein that selectively regulates tubulogenesis vs. glomerulogenesis during mammalian renal development.

    PubMed

    Kanwar, Y S; Kumar, A; Yang, Q; Tian, Y; Wada, J; Kashihara, N; Wallner, E I

    1999-09-28

    Tubulointerstitial nephritis antigen (TIN-ag) is an extracellular matrix protein and is expressed in the renal tubular basement membranes. Its role in metanephric development was investigated. TIN-ag cDNA, isolated from the newborn mouse library, had an ORF of 1,425 nucleotides, a putative signal sequence, and an ATP/GTP-binding site. The translated sequence had approximately 80% identity with rabbit TIN-ag. Among various tissues, TIN-ag mRNA was primarily expressed in the newborn kidney. In the embryonic metanephros, TIN-ag expression was confined to the distal convolution or pole of the S-shaped body, the segment of the nascent nephron that is the progenitor of renal tubules. Treatment with TIN-ag antisense oligodeoxynucleotide induced dysmorphogenesis of the embryonic metanephroi, malformation of the S-shaped body, and a decrease in the tubular population, whereas the glomeruli were unaffected. Treatment also led to a decrease of TIN-Ag mRNA, de novo synthesis of TIN-ag protein, and its antibody reactivity. The mRNA expression of glomerular epithelial protein 1 (a marker for renal podocytes), anti-heparan-sulfate-proteoglycan antibody reactivity, and wheat germ agglutinin lectin staining of the metanephros were unaffected. The anti-TIN-ag antibody treatment also caused deformation of the S-shaped body and a reduction in the tubular population, whereas the glomeruli were unchanged. The data suggest that the TIN-ag, unlike other basement membrane proteins, selectively regulates tubulogenesis, whereas glomerulogenesis is largely unaffected.

  4. Dietary L-arginine supplementation improves the intestinal development through increasing mucosal Akt and mammalian target of rapamycin signals in intra-uterine growth retarded piglets.

    PubMed

    Wang, Yuanxiao; Zhang, Lili; Zhou, Genlai; Liao, Zhiyong; Ahmad, Hussain; Liu, Wenbin; Wang, Tian

    2012-10-28

    Intra-uterine growth retardation (IUGR) impairs postnatal growth and development of the small intestine (SI) in neonatal pigs and infants. L-Arginine (Arg), a critical amino acid involved in promoting growth and metabolism in young mammals, is more deficient in IUGR fetuses. However, little is known whether dietary Arg supplementation would accelerate the impaired development of the SI induced by IUGR in piglets. In the present study, a total of six litters of newborn piglets were used. In each litter, one normal and two IUGR littermates were obtained. Piglets were fed milk-based diets supplemented with 0 (Normal), 0 (IUGR) and 0·60% Arg (IUGR+Arg) from 7 to 14 d of age, respectively. Compared with Normal piglets at 14 d of age, IUGR decreased (P < 0·05) the growth performance, entire SI weight, and villus height in the jejunum and ileum. IUGR piglets had lower (P < 0·05) mucosal concentrations of Arg, insulin, insulin growth factor 1, as well as phosphorylated Akt, mammalian target of rapamycin (mTOR) and p70 S6 kinase but higher (P < 0·05) enterocyte apoptosis index (AI). After Arg treatment in IUGR piglets, the growth performance, weight of entire SI and mucosa, and villus height in the jejunum and ileum were increased (P < 0·05). Diet supplemented with Arg also increased (P < 0·05) the levels of Arg, insulin, phosphorylated Akt and mTOR in SI mucosa of IUGR piglets, and decreased (P < 0·05) the AI and caspase-3 activity. In conclusion, Arg has a beneficiary effect in improving the impaired SI development in IUGR piglets via regulating cell apoptosis and activating Akt and mTOR signals in SI mucosa.

  5. [Dental caries and early childhood development: a pilot study].

    PubMed

    Núñez, F Loreto; Sanz, B Javier; Mejía, L Gloria

    2015-01-01

    To investigate the association between dental caries and early childhood development in 3-year-olds from Talca, Chile. A pilot study with a convenience sample of 3-year-olds from Talca (n = 39) who attend public healthcare centers. Child development was measured by the Psychomotor Development Index (PDI), a screening tool used nationally among pre-school children to assess language development, fine motor skills and coordination areas. Dental caries prevalence was evaluated by decayed, missing, filled teeth (DFMT) and decayed, missing, filled tooth surfaces (DFMS) ceo-d and ceo-s indexes. The children were divided into two groups according to the PDIscore: those with a score of 40 or more were considered developmentally normal (n = 32), and those with a score below 40 were considered as having impaired development (n = 7). The severity of caries (DMFT) was negatively correlated with PDI (r = -0.82), and children with the lowest TEPSI score had the highest DFMT values. The average DMFT in children with normal development was 1.31, and 3.57 for those with impaired development. This pilot study indicates that the severity of dental caries is correlated with early childhood development. Copyright © 2015. Publicado por Elsevier España, S.L.U.

  6. The early Cambrian fossil embryo Pseudooides is a direct-developing cnidarian, not an early ecdysozoan

    PubMed Central

    2017-01-01

    Early Cambrian Pseudooides prima has been described from embryonic and post-embryonic stages of development, exhibiting long germ-band development. There has been some debate about the pattern of segmentation, but this interpretation, as among the earliest records of ecdysozoans, has been generally accepted. Here, we show that the ‘germ band’ of P. prima embryos separates along its mid axis during development, with the transverse furrows between the ‘somites’ unfolding into the polar aperture of the ten-sided theca of Hexaconularia sichuanensis, conventionally interpreted as a scyphozoan cnidarian; co-occurring post-embryonic remains of ecdysozoans are unrelated. We recognize H. sichuanensis as a junior synonym of P. prima as a consequence of identifying these two form-taxa as distinct developmental stages of the same organism. Direct development in P. prima parallels the co-occuring olivooids Olivooides, and Quadrapyrgites and Bayesian phylogenetic analysis of a novel phenotype dataset indicates that, despite differences in their tetra-, penta- and pseudo-hexa-radial symmetry, these hexangulaconulariids comprise a clade of scyphozoan medusozoans, with Arthrochites and conulariids, that all exhibit direct development from embryo to thecate polyp. The affinity of hexangulaconulariids and olivooids to extant scyphozoan medusozoans indicates that the prevalence of tetraradial symmetry and indirect development are a vestige of a broader spectrum of body-plan symmetries and developmental modes that was manifest in their early Phanerozoic counterparts. PMID:29237861

  7. The early Cambrian fossil embryo Pseudooides is a direct-developing cnidarian, not an early ecdysozoan.

    PubMed

    Duan, Baichuan; Dong, Xi-Ping; Porras, Luis; Vargas, Kelly; Cunningham, John A; Donoghue, Philip C J

    2017-12-20

    Early Cambrian Pseudooides prima has been described from embryonic and post-embryonic stages of development, exhibiting long germ-band development. There has been some debate about the pattern of segmentation, but this interpretation, as among the earliest records of ecdysozoans, has been generally accepted. Here, we show that the 'germ band' of P. prima embryos separates along its mid axis during development, with the transverse furrows between the 'somites' unfolding into the polar aperture of the ten-sided theca of Hexaconularia sichuanensis , conventionally interpreted as a scyphozoan cnidarian; co-occurring post-embryonic remains of ecdysozoans are unrelated. We recognize H. sichuanensis as a junior synonym of P. prima as a consequence of identifying these two form-taxa as distinct developmental stages of the same organism. Direct development in P. prima parallels the co-occuring olivooids Olivooides, and Quadrapyrgites and Bayesian phylogenetic analysis of a novel phenotype dataset indicates that, despite differences in their tetra-, penta- and pseudo-hexa-radial symmetry, these hexangulaconulariids comprise a clade of scyphozoan medusozoans, with Arthrochites and conulariids, that all exhibit direct development from embryo to thecate polyp. The affinity of hexangulaconulariids and olivooids to extant scyphozoan medusozoans indicates that the prevalence of tetraradial symmetry and indirect development are a vestige of a broader spectrum of body-plan symmetries and developmental modes that was manifest in their early Phanerozoic counterparts. © 2017 The Authors.

  8. Social conversational skills development in early implanted children.

    PubMed

    Guerzoni, Letizia; Murri, Alessandra; Fabrizi, Enrico; Nicastri, Maria; Mancini, Patrizia; Cuda, Domenico

    2016-09-01

    Social conversational skills are a salient aspect of early pragmatic development in young children. These skills include two different abilities, assertiveness and responsiveness. This study investigated the development of these abilities in early implanted children and their relationships with lexical development and some language-sensitive variables. Prospective, observational, nonrandomized study. Participants included 28 children with congenital profound sensorineural hearing loss. The mean age at device activation was 13.3 months (standard deviation [SD] ±4.2). The Social-Conversational Skills Rating Scale was used to evaluate assertiveness and responsiveness. The MacArthur-Bates Communicative Development Inventory (Words and Sentences form) was used to analyze the lexical development. The device experience was 12 months for each child, and the mean age at testing was 25.9 months (SD ±4.6). Assertiveness and responsiveness scores were within the normal range of normal-hearing age-matched peers. Age at cochlear implant activation exerted a significant impact, with the highest scores associated to the youngest patients. The residual correlations between assertiveness and responsiveness with the lexical development were positive and strongly significant (r = 0.69 and 0.73, respectively). Preoperative hearing threshold demonstrated an associated significant coefficient on the assertiveness score. Age at diagnosis and maternal education level were not correlated with the social conversational skills. Early-implanted children developed social conversational skills that are similar to normal-hearing peers matched for age 1 year after device activation. Social conversational skills and lexical development were strongly correlated, but the present study design cannot specify the direction of this relationship. Children with better preoperative residual hearing exhibited better assertive ability. 4 Laryngoscope, 126:2098-2105, 2016. © 2015 The American Laryngological

  9. [Recent contributions to the establishment of the axes of the mammalian embryo].

    PubMed

    Catala, M

    2002-06-01

    The study of the establishment of embryonic axes during early development has shown that this process is a very early event (occurRing either during ovogenesis or during fertilization) for invertebrates and for lower vertebrates. In mammals, it was considered that this establishment appears late during development because of the great plasticity of blastomeres. Recent data in the mouse embryon show that the mammalian ovocyte is a polarized cell, the polar body corresponding to the animal pole of this cell. The blastomeres that are generated by the zygote divide asynchronously. The first that divides is the one which inherits the plasma cell membrane where fertilization takes place. This blastomere will preferentially give rise to the cells of the embryonic pole of the blastocyst whereas the other yields the cells of the abembryonic pole. The mammalian ovocyte is thus a polarized cell with an already established animal-vegetal axis. The point of sperm entry will determine the embryonic-abembryonic axis.

  10. Relationship between the neighbourhood built environment and early child development.

    PubMed

    Christian, Hayley; Ball, Stephen J; Zubrick, Stephen R; Brinkman, Sally; Turrell, Gavin; Boruff, Bryan; Foster, Sarah

    2017-11-01

    The relationship between features of the neighbourhood built environment and early child development was investigated using area-level data from the Australian Early Development Census. Overall 9.0% of children were developmentally vulnerable on the Physical Health and Well-being domain, 8.1% on the Social Competence domain and 8.1% on the Emotional Maturity domain. After adjustment for socio-demographic factors, Local Communities with the highest quintile of home yard space had significantly lower odds of developmental vulnerability on the Emotional Maturity domain. Residing in a Local Community with fewer main roads was associated with a decrease in the proportion of children developmentally vulnerable on the Social Competence domain. Overall, sociodemographic factors were more important than aspects of the neighbourhood physical environment for explaining variation between Local Communities in the developmental vulnerability of children. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Lexically-based learning and early grammatical development.

    PubMed

    Lieven, E V; Pine, J M; Baldwin, G

    1997-02-01

    Pine & Lieven (1993) suggest that a lexically-based positional analysis can account for the structure of a considerable proportion of children's early multiword corpora. The present study tests this claim on a second, larger sample of eleven children aged between 1;0 and 3;0 from a different social background, and extends the analysis to later in development. Results indicate that the positional analysis can account for a mean of 60% of all the children's multiword utterances and that the great majority of all other utterances are defined as frozen by the analysis. Alternative explanations of the data based on hypothesizing underlying syntactic or semantic relations are investigated through analyses of pronoun case marking and of verbs with prototypical agent-patient roles. Neither supports the view that the children's utterances are being produced on the basis of general underlying rules and categories. The implications of widespread distributional learning in early language development are discussed.

  12. Hazards to Early Development: The Biological Embedding of Early Life Adversity.

    PubMed

    Nelson, Charles A

    2017-10-11

    The number of children under 18 years of age has increased worldwide over the past decade. This growth spurt is due, in part, to remarkable progress in child survival. Alas, surviving early hazards, like prematurity or infectious disease, does not guarantee that children's development will not be compromised by other hazards as they grow older. Throughout the world, children continue to be confronted with a large number of biological and psychosocial challenges that greatly limit their developmental potential. The focus of this article is how such adverse experiences impact the developing brain. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Wnt signalling pathway parameters for mammalian cells.

    PubMed

    Tan, Chin Wee; Gardiner, Bruce S; Hirokawa, Yumiko; Layton, Meredith J; Smith, David W; Burgess, Antony W

    2012-01-01

    Wnt/β-catenin signalling regulates cell fate, survival, proliferation and differentiation at many stages of mammalian development and pathology. Mutations of two key proteins in the pathway, APC and β-catenin, have been implicated in a range of cancers, including colorectal cancer. Activation of Wnt signalling has been associated with the stabilization and nuclear accumulation of β-catenin and consequential up-regulation of β-catenin/TCF gene transcription. In 2003, Lee et al. constructed a computational model of Wnt signalling supported by experimental data from analysis of time-dependent concentration of Wnt signalling proteins in Xenopus egg extracts. Subsequent studies have used the Xenopus quantitative data to infer Wnt pathway dynamics in other systems. As a basis for understanding Wnt signalling in mammalian cells, a confocal live cell imaging measurement technique is developed to measure the cell and nuclear volumes of MDCK, HEK293T cells and 3 human colorectal cancer cell lines and the concentrations of Wnt signalling proteins β-catenin, Axin, APC, GSK3β and E-cadherin. These parameters provide the basis for formulating Wnt signalling models for kidney/intestinal epithelial mammalian cells. There are significant differences in concentrations of key proteins between Xenopus extracts and mammalian whole cell lysates. Higher concentrations of Axin and lower concentrations of APC are present in mammalian cells. Axin concentrations are greater than APC in kidney epithelial cells, whereas in intestinal epithelial cells the APC concentration is higher than Axin. Computational simulations based on Lee's model, with this new data, suggest a need for a recalibration of the model.A quantitative understanding of Wnt signalling in mammalian cells, in particular human colorectal cancers requires a detailed understanding of the concentrations of key protein complexes over time. Simulations of Wnt signalling in mammalian cells can be initiated with the parameters

  14. Early zebrafish development: It’s in the maternal genes

    PubMed Central

    Abrams, Elliott W.; Mullins, Mary C.

    2009-01-01

    Summary The earliest stages of embryonic development in all animals examined rely on maternal gene products that are generated during oogenesis and supplied to the egg. The period of maternal control of embryonic development varies among animals according to the onset of zygotic transcription and the persistence of maternal gene products. This maternal regulation has been little studied in vertebrates, due to the difficulty in manipulating maternal gene function and lack of basic molecular information. However, recent maternal-effect screens in the zebrafish have generated more than 40 unique mutants that are providing new molecular entry points to the maternal control of early vertebrate development. Here we discuss recent studies of 12 zebrafish mutant genes that illuminate the maternal molecular controls on embryonic development, including advances in the regulation of animal-vegetal polarity, egg activation, cleavage development, body plan formation, tissue morphogenesis, microRNA function and germ cell development. PMID:19608405

  15. Reading Instruction Affects the Cognitive Skills Supporting Early Reading Development

    ERIC Educational Resources Information Center

    McGeown, Sarah P.; Johnston, Rhona S.; Medford, Emma

    2012-01-01

    This study examined the cognitive skills associated with early reading development when children were taught by different types of instruction. Seventy-nine children (mean age at pre-test 4;10 (0.22 S.D.) and post-test 5;03 (0.21 S.D.)) were taught to read either by an eclectic approach which included sight-word learning, guessing from context and…

  16. Dynamic Self-Organization and Early Lexical Development in Children

    ERIC Educational Resources Information Center

    Li, Ping; Zhao, Xiaowei; Whinney, Brian Mac

    2007-01-01

    In this study we present a self-organizing connectionist model of early lexical development. We call this model DevLex-II, based on the earlier DevLex model. DevLex-II can simulate a variety of empirical patterns in children's acquisition of words. These include a clear vocabulary spurt, effects of word frequency and length on age of acquisition,…

  17. Early Life Growth Predicts Pubertal Development in South African Adolescents.

    PubMed

    Lundeen, Elizabeth A; Norris, Shane A; Martorell, Reynaldo; Suchdev, Parminder S; Mehta, Neil K; Richter, Linda M; Stein, Aryeh D

    2016-03-01

    Given global trends toward earlier onset of puberty and the adverse psychosocial consequences of early puberty, it is important to understand the childhood predictors of pubertal timing and tempo. We examined the association between early growth and the timing and tempo of puberty in adolescents in South Africa. We analyzed prospectively collected data from 1060 boys and 1135 girls participating in the Birth-to-Twenty cohort in Soweto, South Africa. Height-for-age z scores (HAZs) and body mass index-for-age z scores (BMIZs) were calculated based on height (centimeters) and body mass index (kilograms per meter squared) at ages 5 y and 8 y. The development of genitals, breasts, and pubic hair was recorded annually from 9 to 16 y of age with the use of the Tanner sexual maturation scale (SMS). We used latent class growth analysis to identify pubertal trajectory classes and also characterized children as fast or slow developers based on the SMS score at 12 y of age. We used multinomial logistic regression to estimate associations of HAZ and BMIZ at ages 5 and 8 y with pubertal development. We identified 3 classes for pubic hair development (for both girls and boys) and 4 classes for breast (for girls) and genital (for boys) development. In girls, both HAZ and BMIZ at age 5 y were positively associated with pubic hair development [relative risk ratio (RRR): 1.57, P < 0.001 and RRR: 1.51, P < 0.01, respectively], as was BMI at age 8 y (RRR: 2.06, P = 0.03); similar findings were observed for breast development. In boys, HAZ and BMIZ at age 5 y were positively associated with pubic hair development (RRR: 1.78, P < 0.001 and RRR: 1.43, P < 0.01, respectively); HAZ at age 5 y was associated with development of genitals (RRR: 2.19, P < 0.01). In boys and girls, both height and body mass index in early childhood predicted the trajectory of pubertal development. This may provide a tool to identify children at risk of early pubertal onset.

  18. Biased gene expression in early honeybee larval development

    PubMed Central

    2013-01-01

    Background Female larvae of the honeybee (Apis mellifera) develop into either queens or workers depending on nutrition. This nutritional stimulus triggers different developmental trajectories, resulting in adults that differ from each other in physiology, behaviour and life span. Results To understand how these trajectories are established we have generated a comprehensive atlas of gene expression throughout larval development. We found substantial differences in gene expression between worker and queen-destined larvae at 6 hours after hatching. Some of these early changes in gene expression are maintained throughout larval development, indicating that caste-specific developmental trajectories are established much earlier than previously thought. Within our gene expression data we identified processes that potentially underlie caste differentiation. Queen-destined larvae have higher expression of genes involved in transcription, translation and protein folding early in development with a later switch to genes involved in energy generation. Using RNA interference, we were able to demonstrate that one of these genes, hexamerin 70b, has a role in caste differentiation. Both queen and worker developmental trajectories are associated with the expression of genes that have alternative splice variants, although only a single variant of a gene tends to be differentially expressed in a given caste. Conclusions Our data, based on the biases in gene expression early in development together with published data, supports the idea that caste development in the honeybee consists of two phases; an initial biased phase of development, where larvae can still switch to the other caste by differential feeding, followed by commitment to a particular developmental trajectory. PMID:24350621

  19. Mammalian touch catches up

    PubMed Central

    Walsh, Carolyn M.; Bautista, Diana M.; Lumpkin, Ellen A.

    2015-01-01

    An assortment of touch receptors innervate the skin and encode different tactile features of the environment. Compared with invertebrate touch and other sensory systems, our understanding of the molecular and cellular underpinnings of mammalian touch lags behind. Two recent breakthroughs have accelerated progress. First, an arsenal of cell-type-specific molecular markers allowed the functional and anatomical properties of sensory neurons to be matched, thereby unraveling a cellular code for touch. Such markers have also revealed key roles of non-neuronal cell types, such as Merkel cells and keratinocytes, in touch reception. Second, the discovery of Piezo genes as a new family of mechanically activated channels has fueled the discovery of molecular mechanisms that mediate and mechanotransduction in mammalian touch receptors. PMID:26100741

  20. Homogenization of Mammalian Cells.

    PubMed

    de Araújo, Mariana E G; Lamberti, Giorgia; Huber, Lukas A

    2015-11-02

    Homogenization is the name given to the methodological steps necessary for releasing organelles and other cellular constituents as a free suspension of intact individual components. Most homogenization procedures used for mammalian cells (e.g., cavitation pump and Dounce homogenizer) rely on mechanical force to break the plasma membrane and may be supplemented with osmotic or temperature alterations to facilitate membrane disruption. In this protocol, we describe a syringe-based homogenization method that does not require specialized equipment, is easy to handle, and gives reproducible results. The method may be adapted for cells that require hypotonic shock before homogenization. We routinely use it as part of our workflow to isolate endocytic organelles from mammalian cells. © 2015 Cold Spring Harbor Laboratory Press.

  1. Developing an Early Childhood Teacher Workforce Development Strategy for Rural and Remote Communities

    ERIC Educational Resources Information Center

    Price, Anne; Jackson-Barrett, Elizabeth

    2009-01-01

    The North West Early Childhood and Primary Teacher Workforce Development Strategy offers students in the Pilbara and Kimberley the opportunity to enrol in a Western Australian University's fully accredited Bachelor of Education (Early Childhood and Primary) part time and externally--so they can continue to live and work in their communities. The…

  2. Early mathematics development and later achievement: Further evidence

    NASA Astrophysics Data System (ADS)

    Aubrey, Carol; Godfrey, Ray; Dahl, Sarah

    2006-05-01

    There is a growing international recognition of the importance of the early years of schooling as well as an interest being shown in the relationship of early education to later achievement. This article focuses on a cohort of English pupils who have been tracked through primary school during the first five years of the new National Numeracy Strategy. It reports a limited longitudinal study of young children's early mathematical development, initially within three testing cycles: at the mid-point and towards the end of their reception year (at five years-of-age) and again at the mid-point of Year 1 (at six years-ofage). These cycles were located within the broader context of progress through to the end of Key Stage 1 (at seven years) and Key Stage 2 (at eleven years) on the basis of national standardised assessment tests (SATs). Results showed that children who bring into school early mathematical knowledge do appear to be advantaged in terms of their mathematical progress through primary school. Numerical attainment increases in importance across the primary years and practical problem solving remains an important element of this. This finding is significant given the current emphasis on numerical calculation in the English curriculum. It is concluded that without active intervention, it is likely that children with little mathematical knowledge at the beginning of formal schooling will remain low achievers throughout their primary years and, probably, beyond.

  3. The Mammalian Cervical Vertebrae Blueprint Depends on the T (brachyury) Gene

    PubMed Central

    Kromik, Andreas; Ulrich, Reiner; Kusenda, Marian; Tipold, Andrea; Stein, Veronika M.; Hellige, Maren; Dziallas, Peter; Hadlich, Frieder; Widmann, Philipp; Goldammer, Tom; Baumgärtner, Wolfgang; Rehage, Jürgen; Segelke, Dierck; Weikard, Rosemarie; Kühn, Christa

    2015-01-01

    A key common feature of all but three known mammalian genera is the strict seven cervical vertebrae blueprint, suggesting the involvement of strong conserving selection forces during mammalian radiation. This is further supported by reports indicating that children with cervical ribs die before they reach reproductive age. Hypotheses were put up, associating cervical ribs (homeotic transformations) to embryonal cancer (e.g., neuroblastoma) or ascribing the constraint in cervical vertebral count to the development of the mammalian diaphragm. Here, we describe a spontaneous mutation c.196A > G in the Bos taurus T gene (also known as brachyury) associated with a cervical vertebral homeotic transformation that violates the fundamental mammalian cervical blueprint, but does not preclude reproduction of the affected individual. Genome-wide mapping, haplotype tracking within a large pedigree, resequencing of target genome regions, and bioinformatic analyses unambiguously confirmed the mutant c.196G allele as causal for this previously unknown defect termed vertebral and spinal dysplasia (VSD) by providing evidence for the mutation event. The nonsynonymous VSD mutation is located within the highly conserved T box of the T gene, which plays a fundamental role in eumetazoan body organization and vertebral development. To our knowledge, VSD is the first unequivocally approved spontaneous mutation decreasing cervical vertebrae number in a large mammal. The spontaneous VSD mutation in the bovine T gene is the first in vivo evidence for the hypothesis that the T protein is directly involved in the maintenance of the mammalian seven-cervical vertebra blueprint. It therefore furthers our knowledge of the T-protein function and early mammalian notochord development. PMID:25614605

  4. Rheotaxis guides mammalian sperm

    PubMed Central

    Miki, Kiyoshi; Clapham, David E

    2013-01-01

    Background In sea urchins, spermatozoan motility is altered by chemotactic peptides, giving rise to the assumption that mammalian eggs also emit chemotactic agents that guide spermatozoa through the female reproductive tract to the mature oocyte. Mammalian spermatozoa indeed undergo complex adaptations within the female (the process of capacitation) that are initiated by agents ranging from pH to progesterone, but these factors are not necessarily taxic. Currently, chemotaxis, thermotaxis, and rheotaxis have not been definitively established in mammals. Results Here, we show that positive rheotaxis, the ability of organisms to orient and swim against the flow of surrounding fluid, is a major taxic factor for mouse and human sperm. This flow is generated within 4 hours of sexual stimulation and coitus in female mice; prolactin-triggered oviductal fluid secretion clears the oviduct of debris, lowers viscosity, and generates the stream that guides sperm migration in the oviduct. Rheotaxic movement is demonstrated in capacitated and uncapacitated spermatozoa in low and high viscosity medium. Finally, we show that a unique sperm motion we quantify using the sperm head's rolling rate reflects sperm rotation that generates essential force for positioning the sperm in the stream. Rotation requires CatSper channels, presumably by enabling Ca2+ influx. Conclusions We propose that rheotaxis is a major determinant of sperm guidance over long distances in the mammalian female reproductive tract. Coitus induces fluid flow to guide sperm in the oviduct. Sperm rheotaxis requires rotational motion during CatSper channel-dependent hyperactivated motility. PMID:23453951

  5. Reflections on the early development of poxvirus vectors.

    PubMed

    Moss, Bernard

    2013-09-06

    Poxvirus expression vectors were described in 1982 and quickly became widely used for vaccine development as well as research in numerous fields. Advantages of the vectors include simple construction, ability to accommodate large amounts of foreign DNA and high expression levels. Numerous poxvirus-based veterinary vaccines are currently in use and many others are in human clinical trials. The early reports of poxvirus vectors paved the way for and stimulated the development of other viral vectors and recombinant DNA vaccines. Published by Elsevier Ltd.

  6. Early career professional development issues for military academic psychiatrists.

    PubMed

    Warner, Christopher H; Bobo, William V; Flynn, Julianne

    2005-01-01

    Academically motivated graduates of military psychiatric residency programs confront serious challenges. In this article, the authors present a junior faculty development model organized around four overlapping domains: mentorship, scholarship, research, and career planning/development. Using these four domains as a platform for discussion, the authors focus on challenges facing academically oriented early-career military psychiatrists and provide guidance. The authors believe that a proactive stance, skillful mentoring, self-awareness through conscious planning and effort, ability to capitalize on existing opportunities for growth, and attention to detail are all vital to the junior military psychiatrist.

  7. Development of an assisting detection system for early infarct diagnosis

    SciTech Connect

    Sim, K. S.; Nia, M. E.; Ee, C. S.

    2015-04-24

    In this paper, a detection assisting system for early infarct detection is developed. This new developed method is used to assist the medical practitioners to diagnose infarct from computed tomography images of brain. Using this assisting system, the infarct could be diagnosed at earlier stages. The non-contrast computed tomography (NCCT) brain images are the data set used for this system. Detection module extracts the pixel data from NCCT brain images, and produces the colourized version of images. The proposed method showed great potential in detecting infarct, and helps medical practitioners to make earlier and better diagnoses.

  8. Early childhood development: impact of national human development, family poverty, parenting practices and access to early childhood education.

    PubMed

    Tran, T D; Luchters, S; Fisher, J

    2017-05-01

    This study was to describe and quantify the relationships among family poverty, parents' caregiving practices, access to education and the development of children living in low- and middle-income countries (LAMIC). We conducted a secondary analysis of data collected in UNICEF's Multiple Indicator Cluster Surveys (MICS). Early childhood development was assessed in four domains: language-cognitive, physical, socio-emotional and approaches to learning. Countries were classified into three groups on the basis of the Human Development Index (HDI). Overall, data from 97 731 children aged 36 to 59 months from 35 LAMIC were included in the after analyses. The mean child development scale score was 4.93 out of a maximum score of 10 (95%CI 4.90 to 4.97) in low-HDI countries and 7.08 (95%CI 7.05 to 7.12) in high-HDI countries. Family poverty was associated with lower child development scores in all countries. The total indirect effect of family poverty on child development score via attending early childhood education, care for the child at home and use of harsh punishments at home was -0.13 SD (77.8% of the total effect) in low-HDI countries, -0.09 SD (23.8% of the total effect) in medium-HDI countries and -0.02 SD (6.9% of the total effect) in high-HDI countries. Children in the most disadvantaged position in their societies and children living in low-HDI countries are at the greatest risk of failing to reach their developmental potential. Optimizing care for child development at home is essential to reduce the adverse effects of poverty on children's early development and subsequent life. © 2016 John Wiley & Sons Ltd.

  9. [The mammalian oviduct revisited].

    PubMed

    Halter, S; Reynaud, K; Tahir, Z; Thoumire, S; Chastant-Maillard, S; Saint-Dizier, M

    2011-11-01

    The oviducts, or uterine tubes, support the transport and final maturation of gametes, and harbour fertilization and early embryo development. The oviduct environment is finely regulated by ovarian steroids as well as by gametes and embryos that interact with it. Previously regarded as a simple transit zone, the oviduct is now regarded as a complex organ with multiple functions in these various processes. The tubal fluid, now better characterized, is to be regarded as the first interface between the mother and the embryo. It may play a major role in the quality of the conceptus. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

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

    PubMed

    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. Early Intravascular Events are Associated with Development of ARDS.

    PubMed

    Abdulnour, Raja-Elie E; Gunderson, Tina; Barkas, Ioanna; Timmons, Jack Y; Barnig, Cindy; Gong, Michelle; Kor, Daryl J; Gajic, Ognjen; Talmor, Daniel; Carter, Rickey E; Levy, Bruce D

    2018-05-21

    The acute respiratory distress syndrome (ARDS) is a devastating illness with limited therapeutic options. A better understanding of early biochemical and immunological events in ARDS could inform the development of new preventive and treatment strategies. To determine select peripheral blood lipid mediator and leukocyte responses in patients at-risk for ARDS. Patients at risk for ARDS were randomized as part of a multicenter, double-blind clinical trial of aspirin versus placebo (LIPS-A; NCT01504867). Plasma thromboxane B2 (TxB2), 15-epi-LXA4 (aspirin-triggered lipoxin A4, ATL), and peripheral blood leukocyte number and activation were determined upon enrollment and after treatment with either aspirin or placebo. Thirty-three of 367 subjects (9.0%) developed ARDS after randomization. Baseline ATL levels, total monocyte counts, intermediate monocyte (IntMo) counts, and Mo-PA were associated with the development of ARDS. Peripheral blood neutrophil count and monocyte-platelet aggregates significantly decreased over time. Of note, 9 subjects developed ARDS after randomization yet prior to study drug initiation, including 7 subjects assigned to aspirin treatment. Subjects without ARDS at the time of first dose demonstrated a lower incidence of ARDS with aspirin treatment. Compared with placebo, aspirin significantly decreased TxB2 and increased the ATL/TxB2 ratio. Biomarkers of intravascular monocyte activation in at-risk patients were associated with development of ARDS. The potential clinical benefit of early aspirin for prevention of ARDS remains uncertain. Together, results of the biochemical and immunological analyses provide a window into the early pathogenesis of human ARDS, and represent potential vascular biomarkers of ARDS risk.

  12. Illinois Early Learning Project Tip Sheets: Physical Development and Health.

    ERIC Educational Resources Information Center

    2003

    The Illinois Early Learning Project (IEL) is funded by the Illinois State Board of Education to provide information resources on early learning and training related to implementing the Illinois Early Learning Standards for parents and for early childhood personnel in all settings. The IEL tip sheets offer suggestions to parents and early childhood…

  13. Excess iron: considerations related to development and early growth.

    PubMed

    Wessling-Resnick, Marianne

    2017-12-01

    What effects might arise from early life exposures to high iron? This review considers the specific effects of high iron on the brain, stem cells, and the process of erythropoiesis and identifies gaps in our knowledge of what molecular damage may be incurred by oxidative stress that is imparted by high iron status in early life. Specific areas to enhance research on this topic include the following: longitudinal behavioral studies of children to test associations between iron exposures and mood, emotion, cognition, and memory; animal studies to determine epigenetic changes that reprogram brain development and metabolic changes in early life that could be followed through the life course; and the establishment of human epigenetic markers of iron exposures and oxidative stress that could be monitored for early origins of adult chronic diseases. In addition, efforts to understand how iron exposure influences stem cell biology could be enhanced by establishing platforms to collect biological specimens, including umbilical cord blood and amniotic fluid, to be made available to the research community. At the molecular level, there is a need to better understand stress erythropoiesis and changes in iron metabolism during pregnancy and development, especially with respect to regulatory control under high iron conditions that might promote ineffective erythropoiesis and iron-loading anemia. These investigations should focus not only on factors such as hepcidin and erythroferrone but should also include newly identified interactions between transferrin receptor-2 and the erythropoietin receptor. Finally, despite our understanding that several key micronutrients (e.g., vitamin A, copper, manganese, and zinc) support iron's function in erythropoiesis, how these nutrients interact remains, to our knowledge, unknown. It is necessary to consider many factors when formulating recommendations on iron supplementation. © 2017 American Society for Nutrition.

  14. Regulation of bone morphogenetic proteins in early embryonic development

    NASA Astrophysics Data System (ADS)

    Yamamoto, Yukiyo; Oelgeschläger, Michael

    2004-11-01

    Bone morphogenetic proteins (BMPs), a large subgroup of the TGF-β family of secreted growth factors, control fundamental events in early embryonic development, organogenesis and adult tissue homeostasis. The plethora of dose-dependent cellular processes regulated by BMP signalling demand a tight regulation of BMP activity. Over the last decade, a number of proteins have been identified that bind BMPs in the extracellular space and regulate the interaction of BMPs with their cognate receptors, including the secreted BMP antagonist Chordin. In the early vertebrate embryo, the localized secretion of BMP antagonists from the dorsal blastopore lip establishes a functional BMP signalling gradient that is required for the determination of the dorsoventral or back to belly body axis. In particular, inhibition of BMP activity is essential for the formation of neural tissue in the development of vertebrate and invertebrate embryos. Here we review recent studies that have provided new insight into the regulation of BMP signalling in the extracellular space. In particular, we discuss the recently identified Twisted gastrulation protein that modulates, in concert with metalloproteinases of the Tolloid family, the interaction of Chordin with BMP and a family of proteins that share structural similarities with Chordin in the respective BMP binding domains. In addition, genetic and functional studies in zebrafish and frog provide compelling evidence that the secreted protein Sizzled functionally interacts with the Chd BMP pathway, despite being expressed ventrally in the early gastrula-stage embryo. These intriguing discoveries may have important implications, not only for our current concept of early embryonic patterning, but also for the regulation of BMP activity at later developmental stages and tissue homeostasis in the adult.

  15. Early somatosensory processing in individuals at risk for developing psychoses.

    PubMed

    Hagenmuller, Florence; Heekeren, Karsten; Theodoridou, Anastasia; Walitza, Susanne; Haker, Helene; Rössler, Wulf; Kawohl, Wolfram

    2014-01-01

    Human cortical somatosensory evoked potentials (SEPs) allow an accurate investigation of thalamocortical and early cortical processing. SEPs reveal a burst of superimposed early (N20) high-frequency oscillations around 600 Hz. Previous studies reported alterations of SEPs in patients with schizophrenia. This study addresses the question whether those alterations are also observable in populations at risk for developing schizophrenia or bipolar disorders. To our knowledge to date, this is the first study investigating SEPs in a population at risk for developing psychoses. Median nerve SEPs were investigated using multichannel EEG in individuals at risk for developing bipolar disorders (n = 25), individuals with high-risk status (n = 59) and ultra-high-risk status for schizophrenia (n = 73) and a gender and age-matched control group (n = 45). Strengths and latencies of low- and high-frequency components as estimated by dipole source analysis were compared between groups. Low- and high-frequency source activity was reduced in both groups at risk for schizophrenia, in comparison to the group at risk for bipolar disorders. HFO amplitudes were also significant reduced in subjects with high-risk status for schizophrenia compared to healthy controls. These differences were accentuated among cannabis non-users. Reduced N20 source strengths were related to higher positive symptom load. These results suggest that the risk for schizophrenia, in contrast to bipolar disorders, may involve an impairment of early cerebral somatosensory processing. Neurophysiologic alterations in schizophrenia precede the onset of initial psychotic episode and may serve as indicator of vulnerability for developing schizophrenia.

  16. Early somatosensory processing in individuals at risk for developing psychoses

    PubMed Central

    Hagenmuller, Florence; Heekeren, Karsten; Theodoridou, Anastasia; Walitza, Susanne; Haker, Helene; Rössler, Wulf; Kawohl, Wolfram

    2014-01-01

    Human cortical somatosensory evoked potentials (SEPs) allow an accurate investigation of thalamocortical and early cortical processing. SEPs reveal a burst of superimposed early (N20) high-frequency oscillations around 600 Hz. Previous studies reported alterations of SEPs in patients with schizophrenia. This study addresses the question whether those alterations are also observable in populations at risk for developing schizophrenia or bipolar disorders. To our knowledge to date, this is the first study investigating SEPs in a population at risk for developing psychoses. Median nerve SEPs were investigated using multichannel EEG in individuals at risk for developing bipolar disorders (n = 25), individuals with high-risk status (n = 59) and ultra-high-risk status for schizophrenia (n = 73) and a gender and age-matched control group (n = 45). Strengths and latencies of low- and high-frequency components as estimated by dipole source analysis were compared between groups. Low- and high-frequency source activity was reduced in both groups at risk for schizophrenia, in comparison to the group at risk for bipolar disorders. HFO amplitudes were also significant reduced in subjects with high-risk status for schizophrenia compared to healthy controls. These differences were accentuated among cannabis non-users. Reduced N20 source strengths were related to higher positive symptom load. These results suggest that the risk for schizophrenia, in contrast to bipolar disorders, may involve an impairment of early cerebral somatosensory processing. Neurophysiologic alterations in schizophrenia precede the onset of initial psychotic episode and may serve as indicator of vulnerability for developing schizophrenia. PMID:25309363

  17. The Proteomic Signature of Aspergillus fumigatus During Early Development*

    PubMed Central

    Cagas, Steven E.; Jain, Mohit Raja; Li, Hong; Perlin, David S.

    2011-01-01

    Aspergillus fumigatus is a saprophytic fungus that causes a range of diseases in humans including invasive aspergillosis. All forms of disease begin with the inhalation of conidia, which germinate and develop. Four stages of early development were evaluated using the gel free system of isobaric tagging for relative and absolute quantitation to determine the full proteomic profile of the pathogen. A total of 461 proteins were identified at 0, 4, 8, and 16 h and fold changes for each were established. Ten proteins including the hydrophobin rodlet protein RodA and a protein involved in melanin synthesis Abr2 were found to decrease relative to conidia. To generate a more comprehensive view of early development, a whole genome microarray analysis was performed comparing conidia to 8 and 16 h of growth. A total of 1871 genes were found to change significantly at 8 h with 1001 genes up-regulated and 870 down-regulated. At 16 h, 1235 genes changed significantly with 855 up-regulated and 380 down-regulated. When a comparison between the proteomics and microarray data was performed at 8 h, a total of 22 proteins with significant changes also had corresponding genes that changed significantly. When the same comparison was performed at 16 h, 12 protein and gene combinations were found. This study, the most comprehensive to date, provides insights into early pathways activated during growth and development of A. fumigatus. It reveals a pathogen that is gearing up for rapid growth by building translation machinery, generating ATP, and is very much committed to aerobic metabolism. PMID:21825280

  18. Clinical assessment of early language development: a simplified short form of the Mandarin communicative development inventory.

    PubMed

    Soli, Sigfrid D; Zheng, Yun; Meng, Zhaoli; Li, Gang

    2012-09-01

    The purpose of this study was to develop a practical mean for clinical evaluation of early pediatric language development by establishing developmental trajectories for receptive and expressive vocabulary growth in children between 6 and 32 months of age using a simple, time-efficient assessment tool. Simplified short form versions of the Words and Gestures and Words and Sentences vocabulary inventories in the Mandarin Communicative Development Inventory [1] were developed and used to assess early language development in developmentally normal children from 6 to 32 months of age during routine health checks. Developmental trajectories characterizing the rate of receptive and expressive vocabulary growth between 6 and 32 months of age are reported. These trajectories allow the equivalent age corresponding to a score to be determined after a brief structured interview with the child's parents that can be conducted in a busy clinical setting. The simplified short forms of the Mandarin Communicative Development Inventories can serve as a clinically useful tool to assess early child language development, providing a practical mean of objectively assessing early language development following early interventions to treat young children with hearing impairment as well as speech and language delays. Objective evidence of language development is essential for achievement of effective (re)habilitation outcomes. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  19. Toward an Integrated View of Early Language and Communication Development and Socioemotional Development.

    ERIC Educational Resources Information Center

    Prizant, Barry M.; Wetherby, Amy M.

    1990-01-01

    The article reviews literature on the integrated nature of early communication and socioemotional development in children. It discusses two models, one addressing the role of the development of mutual (interactive) and self-regulatory capacities in young children's socioemotional development, and a transactional model conceptualizing the complex…

  20. Chaos, Poverty, and Parenting: Predictors of Early Language Development

    PubMed Central

    Vernon-Feagans, Lynne; Garrett-Peters, Patricia; Willoughby, Mike; Mills-Koonce, Roger

    2011-01-01

    Studies have shown that distal family risk factors like poverty and maternal education are strongly related to children's early language development. Yet, few studies have examined these risk factors in combination with more proximal day-to-day experiences of children that might be critical to understanding variation in early language. Young children's exposure to a chronically chaotic household may be one critical experience that is related to poorer language, beyond the contribution of SES and other demographic variables. In addition, it is not clear whether parenting might mediate the relationship between chaos and language. The purpose of this study was to understand how multiple indicators of chaos over children's first three years of life, in a representative sample of children living in low wealth rural communities, were related to child expressive and receptive language at 36 months. Factor analysis of 10 chaos indicators over five time periods suggested two factors that were named household disorganization and instability. Results suggested that after accounting for thirteen covariates like maternal education and poverty, one of two chaos composites (household disorganization) accounted for significant variance in receptive and expressive language. Parenting partially mediated this relationship although household disorganization continued to account for unique variance in predicting early language. PMID:23049162

  1. Macrosomia has its roots in early placental development

    PubMed Central

    Schwartz, Nadav; Quant, Hayley S.; Sammel, Mary D.; PARRY, Samuel

    2014-01-01

    Introduction We sought to determine if early placental size, as measured by 3-dimensional ultrasonography, is associated with an increased risk of delivering a macrosomic or large-for-gestational age (LGA) infant. Methods We prospectively collected 3-dimensional ultrasound volume sets of singleton pregnancies at 11–14 weeks and 18–24 weeks. Birth weights were collected from the medical records. After delivery, the ultrasound volume set were used to measure the placental volume (PV) and placental quotient (PQ=PV/gestational age), as well as the mean placental and chorionic diameters (MPD and MCD, respectively). Placental measures were analyzed as predictors of macrosomia (birth weight ≥4000 grams) and LGA (birth weight ≥90th percentile). Results The 578 pregnancies with first trimester volumes included 44 (7.6%) macrosomic and 43 (7.4%) LGA infants. 373 subjects also had second trimester volumes available. A higher PV and PQ were both significantly associated with macrosomia and LGA in both the first and second trimesters. Second trimester MPD was significantly associated with both outcomes as well, while second trimester MCD was only associated with LGA. The above associations remained significant after adjusting for maternal demographic variables such as race, ethnicity, age and diabetes. Adjusted models yielded moderate prediction of macrosomia and LGA (AUC: 0.71–0.77). Conclusions Sonographic measurement of the early placenta can identify pregnancies at greater risk of macrosomia and LGA. Macrosomia and LGA are already determined in part by early placental growth and development. PMID:25064071

  2. Fathers’ Sensitive Parenting and the Development of Early Executive Functioning

    PubMed Central

    Towe-Goodman, Nissa R.; Willoughby, Michael; Blair, Clancy; Gustafsson, Hanna C.; Mills-Koonce, W. Roger; Cox, Martha J.

    2014-01-01

    Using data from a diverse sample of 620 families residing in rural, predominately low-income communities, this study examined longitudinal links between fathers’ sensitive parenting in infancy and toddlerhood and children’s early executive functioning, as well as the contribution of maternal sensitive parenting. After accounting for the quality of concurrent and prior parental care, children’s early cognitive ability, and other child and family factors, fathers’ and mothers’ sensitive and supportive parenting during play at 24-months predicted children’s executive functioning at 3-years of age. In contrast, paternal parenting quality during play at 7-months did not make an independent contribution above that of maternal care, but the links between maternal sensitive and supportive parenting and executive functioning seemed to operate in similar ways during infancy and toddlerhood. These findings add to prior work on early experience and children’s executive functioning, suggesting that both fathers and mothers play a distinct and complementary role in the development of these self-regulatory skills. PMID:25347539

  3. Regulation of endoderm formation and left-right asymmetry by miR-92 during early zebrafish development

    PubMed Central

    Li, Nan; Wei, Chunyao; Olena, Abigail F.; Patton, James G.

    2011-01-01

    microRNAs (miRNAs) are a family of 21-23 nucleotide endogenous non-coding RNAs that post-transcriptionally regulate gene expression in a sequence-specific manner. Typically, miRNAs downregulate target genes by recognizing and recruiting protein complexes to 3′UTRs, followed by translation repression or mRNA degradation. miR-92 is a well-studied oncogene in mammalian systems. Here, using zebrafish as a model system, we uncovered a novel tissue-inductive role for miR-92 during early vertebrate development. Overexpression resulted in reduced endoderm formation during gastrulation with consequent cardia and viscera bifida. By contrast, depletion of miR-92 increased endoderm formation, which led to abnormal Kupffer's vesicle development and left-right patterning defects. Using target prediction algorithms and reporter constructs, we show that gata5 is a target of miR-92. Alteration of gata5 levels reciprocally mirrored the effects of gain and loss of function of miR-92. Moreover, genetic epistasis experiments showed that miR-92-mediated defects could be substantially suppressed by modulating gata5 levels. We propose that miR-92 is a critical regulator of endoderm formation and left-right asymmetry during early zebrafish development and provide the first evidence for a regulatory function for gata5 in the formation of Kupffer's vesicle and left-right patterning. PMID:21447552

  4. Diversification of intrinsic motoneuron electrical properties during normal development and botulinum toxin-induced muscle paralysis in early postnatal mice.

    PubMed

    Nakanishi, S T; Whelan, P J

    2010-05-01

    During early postnatal development, between birth and postnatal days 8-11, mice start to achieve weight-bearing locomotion. In association with the progression of weight-bearing locomotion there are presumed developmental changes in the intrinsic electrical properties of spinal -motoneurons. However, these developmental changes in the properties of -motoneuron properties have not been systematically explored in mice. Here, data are presented documenting the developmental changes of selected intrinsic motoneuron electrical properties, including statistically significant changes in action potential half-width, intrinsic excitability and diversity (quantified as coefficient of variation) of rheobase current, afterhyperpolarization half-decay time, and input resistance. In various adult mammalian preparations, the maintenance of intrinsic motoneuron electrical properties is dependent on activity and/or transmission-sensitive motoneuron-muscle interactions. In this study, we show that botulinum toxin-induced muscle paralysis led to statistically significant changes in the normal development of intrinsic motoneuron electrical properties in the postnatal mouse. This suggests that muscle activity during early neonatal life contributes to the development of normal motoneuron electrical properties.

  5. Regional early development and eruption of permanent teeth: case report.

    PubMed

    Al Mullahi, A M; Bakathir, A; Al Jahdhami, S

    2017-02-01

    Early development and eruption of permanent teeth are rarely reported in scientific literature. Early eruption of permanent teeth has been reported to occur due to local factors such as trauma or dental abscesses in primary teeth, and in systemic conditions. Congenital diffuse infiltrating facial lipomatosis (CDIFL) is a rare condition that belongs to a group of lipomatosis tumours. In this disorder, the mature adipocytes invade adjacent soft and hard tissues in the facial region. Accelerated tooth eruption is one of the dental anomalies associated with CDIFL. A 3-year-old boy presented with a swelling of the lower lip localised early development and eruption of permanent teeth and dental caries involving many primary teeth. The planned treatment included biopsy of the swollen lower lip to confirm the diagnosis, surgical reduction and reconstruction of lip aesthetics. The management of the carious primary teeth included preventative and comprehensive dental care and extractions. These procedures were completed under general anaesthesia due to the child's young age and poor cooperation. The lip biopsy showed features of CDIFL such as the presence of infiltrating adipose tissue, prominent number of nerve bundles and thickened vessels. The high recurrence rate of CDIFL mandates long-term monitoring during the facial growth period of the child. Follow-up care by the paediatric dentist and maxillofacial surgeon has been required to manage all aspects of this congenital malformation. This rare disorder has many implications affecting child's facial aesthetics, psychological well being, developing occlusion and risk of dental caries. A multi-disciplinary approach is needed for management of this condition.

  6. Environmental estrogens alter early development in Xenopus laevis.

    PubMed

    Bevan, Cassandra L; Porter, Donna M; Prasad, Anita; Howard, Marthe J; Henderson, Leslie P

    2003-04-01

    A growing number of environmental toxicants found in pesticides, herbicides, and industrial solvents are believed to have deleterious effects on development by disrupting hormone-sensitive processes. We exposed Xenopus laevis embryos at early gastrula to the commonly encountered environmental estrogens nonylphenol, octylphenol, and methoxychlor, the antiandrogen, p,p-DDE, or the synthetic androgen, 17 alpha-methyltestosterone at concentrations ranging from 10 nM to 10 microM and examined them at tailbud stages (approximately 48 hr of treatment). Exposure to the three environmental estrogens, as well as to the natural estrogen 17 beta-estradiol, increased mortality, induced morphologic deformations, increased apoptosis, and altered the deposition and differentiation of neural crest-derived melanocytes in tailbud stage embryos. Although neural crest-derived melanocytes were markedly altered in embryos treated with estrogenic toxicants, expression of the early neural crest maker Xslug, a factor that regulates both the induction and subsequent migration of neural crest cells, was not affected, suggesting that the disruption induced by these compounds with respect to melanocyte development may occur at later stages of their differentiation. Co-incubation of embryos with the pure antiestrogen ICI 182,780 blocked the ability of nonylphenol to induce abnormalities in body shape and in melanocyte differentiation but did not block the effects of methoxychlor. Our data indicate not only that acute exposure to these environmental estrogens induces deleterious effects on early vertebrate development but also that different environmental estrogens may alter the fate of a specific cell type via different mechanisms. Finally, our data suggest that the differentiation of neural crest-derived melanocytes may be particularly sensitive to the disruptive actions of these ubiquitous chemical contaminants.

  7. Development of a GNSS-Enhanced Tsunami Early Warning System

    NASA Astrophysics Data System (ADS)

    Bawden, G. W.; Melbourne, T. I.; Bock, Y.; Song, Y. T.; Komjathy, A.

    2015-12-01

    The past decade has witnessed a terrible loss of life and economic disruption caused by large earthquakes and resultant tsunamis impacting coastal communities and infrastructure across the Indo-Pacific region. NASA has funded the early development of a prototype real-time Global Navigation Satellite System (RT-GNSS) based rapid earthquake and tsunami early warning (GNSS-TEW) system that may be used to enhance seismic tsunami early warning systems for large earthquakes. This prototype GNSS-TEW system geodetically estimates fault parameters (earthquake magnitude, location, strike, dip, and slip magnitude/direction on a gridded fault plane both along strike and at depth) and tsunami source parameters (seafloor displacement, tsunami energy scale, and 3D tsunami initials) within minutes after the mainshock based on dynamic numerical inversions/regressions of the real-time measured displacements within a spatially distributed real-time GNSS network(s) spanning the epicentral region. It is also possible to measure fluctuations in the ionosphere's total electron content (TEC) in the RT-GNSS data caused by the pressure wave from the tsunami. This TEC approach can detect if a tsunami has been triggered by an earthquake, track its waves as they propagate through the oceanic basins, and provide upwards of 45 minutes early warning. These combined real-time geodetic approaches will very quickly address a number of important questions in the immediate minutes following a major earthquake: How big was the earthquake and what are its fault parameters? Could the earthquake have produced a tsunami and was a tsunami generated?

  8. Gross motor development is delayed following early cardiac surgery.

    PubMed

    Long, Suzanne H; Harris, Susan R; Eldridge, Beverley J; Galea, Mary P

    2012-10-01

    To describe the gross motor development of infants who had undergone cardiac surgery in the neonatal or early infant period. Gross motor performance was assessed when infants were 4, 8, 12, and 16 months of age with the Alberta Infant Motor Scale. This scale is a discriminative gross motor outcome measure that may be used to assess infants from birth to independent walking. Infants were videotaped during the assessment and were later evaluated by a senior paediatric physiotherapist who was blinded to each infant's medical history, including previous clinical assessments. Demographic, diagnostic, surgical, critical care, and medical variables were considered with respect to gross motor outcomes. A total of 50 infants who underwent elective or emergency cardiac surgery at less than or up to 8 weeks of age, between July 2006 and January 2008, were recruited to this study and were assessed at 4 months of age. Approximately, 92%, 84%, and 94% of study participants returned for assessment at 8, 12, and 16 months of age, respectively. Study participants had delayed gross motor development across all study time points; 62% of study participants did not have typical gross motor development during the first year of life. Hospital length of stay was associated with gross motor outcome across infancy. Active gross motor surveillance of all infants undergoing early cardiac surgery is recommended. Further studies of larger congenital heart disease samples are required, as are longitudinal studies that determine the significance of these findings at school age and beyond.

  9. Early anther ablation triggers parthenocarpic fruit development in tomato.

    PubMed

    Medina, Mónica; Roque, Edelín; Pineda, Benito; Cañas, Luis; Rodriguez-Concepción, Manuel; Beltrán, José Pío; Gómez-Mena, Concepción

    2013-08-01

    Fruit set and fruit development in tomato is largely affected by changes in environmental conditions, therefore autonomous fruit set independent of fertilization is a highly desirable trait in tomato. Here, we report the production and characterization of male-sterile transgenic plants that produce parthenocarpic fruits in two tomato cultivars (Micro-Tom and Moneymaker). We generated male-sterility using the cytotoxic gene barnase targeted to the anthers with the PsEND1 anther-specific promoter. The ovaries of these plants grew in the absence of fertilization producing seedless, parthenocarpic fruits. Early anther ablation is essential to trigger the developing of the transgenic ovaries into fruits, in the absence of the signals usually generated during pollination and fertilization. Ovaries are fully functional and can be manually pollinated to obtain seeds. The transgenic plants obtained in the commercial cultivar Moneymaker show that the parthenocarpic development of the fruit does not have negative consequences in fruit quality. Throughout metabolomic analyses of the tomato fruits, we have identified two elite lines which showed increased levels of several health promoting metabolites and volatile compounds. Thus, early anther ablation can be considered a useful tool to promote fruit set and to obtain seedless and good quality fruits in tomato plants. These plants are also useful parental lines to be used in hybrid breeding approaches. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  10. Early Numeracy Assessment: The Development of the Preschool Numeracy Scales

    PubMed Central

    Purpura, David J.; Lonigan, Christopher J.

    2015-01-01

    Research Findings The focus of this study was to construct and validate twelve brief early numeracy assessment tasks that measure the skills and concepts identified as key to early mathematics development by the National Council of Teachers of Mathematics (2006) and the National Mathematics Advisory Panel (2008)—as well as critical developmental precursors to later mathematics skill by the Common Core State Standards (CCSS; 2010). Participants were 393 preschool children ages 3 to 5 years old. Measure development and validation occurred through three analytic phases designed to ensure that the measures were brief, reliable, and valid. These measures included: one-to-one counting, cardinality, counting subsets, subitizing, number comparison, set comparison, number order, numeral identification, set-to-numerals, story problems, number combinations, and verbal counting. Practice or Policy Teachers have extensive demands on their time, yet, they are tasked with ensuring that all students’ academic needs are met. To identify individual instructional needs and measure progress, they need to be able to efficiently assess children’s numeracy skills. The measures developed in this study are not only reliable and valid, but also easy to use and can be utilized for measuring the effects of targeted instruction on individual numeracy skills. PMID:25709375

  11. APECS: A Network for Polar Early Career Scientist Professional Development

    NASA Astrophysics Data System (ADS)

    Enderlin, E. M.

    2014-12-01

    The Association of Polar Early Career Researchers (APECS) is an international and interdisciplinary organization for undergraduate and graduate students, postdoctoral researchers, early faculty members, educators and others with interests in the polar regions, alpine regions and the wider Cryosphere. APECS is a scientific, non-profit organization with free individual membership that aims to stimulate research collaborations and develop effective future leaders in polar research, education, and outreach. APECS grew out of the 4th International Polar Year (2007-08), which emphasized the need to stimulate and nurture the next generation of scientists in order to improve the understanding and communication of the polar regions and its global connections. The APECS organizational structure includes a Council and an elected Executive Committee that are supported by a Directorate. These positions are open to all individual members through a democratic process. The APECS Directorate is funded by the Norwegian Research Council, the University of Tromsø and the Norwegian Polar Institute and is hosted by the University of Tromsø. Early career scientists benefit from a range of activities hosted/organized by APECS. Every year, numerous activities are run with partner organizations and in conjunction with major polar conferences and meetings. In-person and online panels and workshops focus on a range of topics, from developing field skills to applying for a job after graduate school. Career development webinars are hosted each fall and topical research webinars are hosted throughout the year and archived online (http://www.apecs.is). The APECS website also contains abundant information on polar news, upcoming conferences and meetings, and job postings for early career scientists. To better respond to members' needs, APECS has national/regional committees that are linked to the international overarching organization. Many of these committees organize regional meetings or

  12. Mammalian Cell Tissue Culture.

    PubMed

    Phelan, Katy; May, Kristin M

    2017-07-11

    Cultured mammalian cells are used extensively in the field of human genetics. It requires a number of special skills in order to be able to preserve the structure, function, behavior, and biology of the cells in culture. This unit describes the basic skills required to maintain and preserve cell cultures: maintaining aseptic technique, preparing media with the appropriate characteristics, passaging, freezing and storage, recovering frozen stocks, and counting viable cells. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  13. Mammalian diversity: gametes, embryos and reproduction.

    PubMed

    Behringer, Richard R; Eakin, Guy S; Renfree, Marilyn B

    2006-01-01

    The class Mammalia is composed of approximately 4800 extant species. These mammalian species are divided into three subclasses that include the monotremes, marsupials and eutherians. Monotremes are remarkable because these mammals are born from eggs laid outside of the mother's body. Marsupial mammals have relatively short gestation periods and give birth to highly altricial young that continue a significant amount of 'fetal' development after birth, supported by a highly sophisticated lactation. Less than 10% of mammalian species are monotremes or marsupials, so the great majority of mammals are grouped into the subclass Eutheria, including mouse and human. Mammals exhibit great variety in morphology, physiology and reproduction. In the present article, we highlight some of this remarkable diversity relative to the mouse, one of the most widely used mammalian model organisms, and human. This diversity creates challenges and opportunities for gamete and embryo collection, culture and transfer technologies.

  14. Odor Coding by a Mammalian Receptor Repertoire

    PubMed Central

    Saito, Harumi; Chi, Qiuyi; Zhuang, Hanyi; Matsunami, Hiro; Mainland, Joel D.

    2009-01-01

    Deciphering olfactory encoding requires a thorough description of the ligands that activate each odorant receptor (OR). In mammalian systems, however, ligands are known for fewer than 50 of over 1400 human and mouse ORs, greatly limiting our understanding of olfactory coding. We performed high-throughput screening of 93 odorants against 464 ORs expressed in heterologous cells and identified agonists for 52 mouse and 10 human ORs. We used the resulting interaction profiles to develop a predictive model relating physicochemical odorant properties, OR sequences, and their interactions. Our results provide a basis for translating odorants into receptor neuron responses and unraveling mammalian odor coding. PMID:19261596

  15. Medical students' professional identity development in an early nursing attachment.

    PubMed

    Helmich, Esther; Derksen, Els; Prevoo, Mathieu; Laan, Roland; Bolhuis, Sanneke; Koopmans, Raymond

    2010-07-01

    The importance of early clinical experience for medical training is well documented. However, to our knowledge there are no studies that assess the influence of very early nursing attachments on the professional development and identity construction of medical students. Working as an assistant nurse while training to be a doctor may offer valuable learning experiences, but may also present the student with difficulties with respect to identity and identification issues. The aim of the present study was to describe first-year medical students' perceptions of nurses, doctors and their own future roles as doctors before and after a nursing attachment. A questionnaire containing open questions concerning students' perceptions of nurses, doctors and their own future roles as doctors was administered to all Year 1 medical students (n=347) before and directly after a 4-week nursing attachment in hospitals and nursing homes. We carried out two confirmatory focus group interviews. We analysed the data using qualitative and quantitative content analyses. The questionnaire was completed by 316 students (response rate 91%). Before starting the attachment students regarded nurses as empathic, communicative and responsible. After the attachment students reported nurses had more competencies and responsibilities than they had expected. Students' views of doctors were ambivalent. Before and after the attachment, doctors were seen as interested and reliable, but also as arrogant, detached and insensible. However, students maintained positive views of their own future roles as doctors. Students' perceptions were influenced by age, gender and place of attachment. An early nursing attachment engenders more respect for the nursing profession. The ambivalent view of doctors needs to be explored further in relation to students' professional development. It would seem relevant to attune supervision to the age and gender differences revealed in this study.

  16. Early Childhood Development and Iranian Parents' Knowledge: A Qualitative Study.

    PubMed

    Habibi, Elham; Sajedi, Firouzeh; Afzali, Hosein Malek; Hatamizadeh, Nikta; Shahshahanipour, Soheila; Glascoe, Frances Page

    2017-01-01

    Early childhood is the most important step throughout the lifespan and it is a critical period continuing to the end of 8-year-old. Mothers' knowledge is one of the important aspects of child development. The goals of this study were to determine the situation of knowledge in Iranian parents about the concept and the importance of early childhood development (ECD) and determining the sources of parental knowledge about ECD from the perspective of parents and grandparents. This qualitative study was conducted based on the directional content analysis in 2016. The purposive sampling method is utilized to select 24 participants among parents and grandparents in Tehran. The inclusion criteria consisted of speaking in Persian and having a child or grandchild <3-year-old. Data were collected through four focus group discussions and four individual interviews. Iranian parental knowledge about integrative ECD is not enough, their knowledge about motor development and speech and language are relatively better, about cognitive development is little and socialemotional is very little. They said parents and other caregivers influence the process of children's development. Parents' knowledge resources about ECD included human resources, physical resources, virtual space, and the media. According to the majority of participants, "pediatricians are the most reliable source of parents' knowledge about ECD" even though the main focus of pediatricians is on treating diseases, physical health, and growth of children. According to the results, the knowledge of Iranian parent is not enough about ECD; therefore, actions must be taken to increase their knowledge in these domains. Parents look for reliable and valid sources to enhance their knowledge and they rely the most on pediatricians in this regard. Therefore, more studies on assessing parents' knowledge in community and the practical methods for knowledge promotion in this field is recommended.

  17. Early-stage aeolian protodune development and migration

    NASA Astrophysics Data System (ADS)

    Nield, J. M.; Baddock, M. C.; Wiggs, G.

    2017-12-01

    Early-stage bedforms, or protodunes, can be observed to form on sandy beaches, desert gravels or superimposed on the surfaces of larger dunes and can develop topography of 0.1 m or more over several hours. These protodunes are the precursors to embryo and eventually mature dunes, and so it is important to understand how feedbacks between flow, transport and form contribute to this development sequence. Whilst theory and conceptual models have offered some explanation for protodune existence and development, we know surprisingly little about how these bedforms initiate and migrate because it is difficult to measure small changes in form (millimetres; seconds) on highly active surfaces of limited topographic expression. Here, we employ terrestrial laser scanning (TLS) to measure morphological change at the high frequency and spatial resolution (sub-millimetre) required to gain new insights into protodune behaviour. Along with TLS derived saltation and surface moisture, additional sediment flux and windspeed measurements help to elucidate how the protodune topography interacts with airflow and sand transport. We focus on a number of coastal bedforms in various development stages including a 0.06 m high protodune which grew vertically by 0.005 m in two hours with the switch from erosion to deposition identified to occur at a point 0.07 m upwind of the crest. This growth was associated with a reduction in time-averaged sediment flux of 18% over the crestal region. We also observed a decline in lower stoss slope steepness (by 3°) and a steepening of the lee slope, indicating a reshaping of initial protodune form towards the morphology of a more mature dune. Our findings highlight the crucial role of form-flow feedbacks, even on very small bedforms, in driving early-stage bedform growth and development, and show how the use of high resolution TLS to measure both surface topography and grains moving above the surface, can offer new insights into a long standing deficiency

  18. Determinants of early child development in rural Tanzania.

    PubMed

    Ribe, Ingeborg G; Svensen, Erling; Lyngmo, Britt A; Mduma, Estomih; Hinderaker, Sven G

    2018-01-01

    It has been estimated that more than 200 million children under the age of five do not reach their full potential in cognitive development. Much of what we know about brain development is based on research from high-income countries. There is limited evidence on the determinants of early child development in low-income countries, especially rural sub-Saharan Africa. The present study aimed to identify the determinants of cognitive development in children living in villages surrounding Haydom, a rural area in north-central Tanzania. This cohort study is part of the MAL-ED (The Interactions of Malnutrition & Enteric Infections: Consequences for Child Health and Development) multi-country consortium studying risk factors for ill health and poor development in children. Descriptive analysis and linear regression analyses were performed. Associations between nutritional status, socio-economic status, and home environment at 6 months of age and cognitive outcomes at 15 months of age were studied. The third edition of the Bayley Scales for Infant and Toddler Development was used to assess cognitive, language and motor development. There were 262 children enrolled into the study, and this present analysis included the 137 children with data for 15-month Bayley scores. Univariate regression analysis, weight-for-age and weight-for-length z-scores at 6 months were significantly associated with 15-month Bayley gross motor score, but not with other 15-month Bayley scores. Length-for-age z-scores at 6 months were not significantly associated with 15-month Bayley scores. The socio-economic status, measured by a set of assets and monthly income was significantly associated with 15-month Bayley cognitive score, but not with language, motor, nor total 15-month Bayley scores. Other socio-economic variables were not significantly associated with 15-month Bayley scores. No significant associations were found between the home environment and 15-month Bayley scores. In multivariate

  19. Downregulation of ribosome biogenesis during early forebrain development

    PubMed Central

    Chau, Kevin F; Shannon, Morgan L; Fame, Ryann M; Fonseca, Erin; Mullan, Hillary; Johnson, Matthew B; Sendamarai, Anoop K; Springel, Mark W; Laurent, Benoit

    2018-01-01

    Forebrain precursor cells are dynamic during early brain development, yet the underlying molecular changes remain elusive. We observed major differences in transcriptional signatures of precursor cells from mouse forebrain at embryonic days E8.5 vs. E10.5 (before vs. after neural tube closure). Genes encoding protein biosynthetic machinery were strongly downregulated at E10.5. This was matched by decreases in ribosome biogenesis and protein synthesis, together with age-related changes in proteomic content of the adjacent fluids. Notably, c-MYC expression and mTOR pathway signaling were also decreased at E10.5, providing potential drivers for the effects on ribosome biogenesis and protein synthesis. Interference with c-MYC at E8.5 prematurely decreased ribosome biogenesis, while persistent c-MYC expression in cortical progenitors increased transcription of protein biosynthetic machinery and enhanced ribosome biogenesis, as well as enhanced progenitor proliferation leading to subsequent macrocephaly. These findings indicate large, coordinated changes in molecular machinery of forebrain precursors during early brain development. PMID:29745900

  20. Early Development of the Gut Microbiota and Immune Health

    PubMed Central

    Francino, M. Pilar

    2014-01-01

    In recent years, the increase in human microbiome research brought about by the rapidly evolving “omic” technologies has established that the balance among the microbial groups present in the human gut, and their multipronged interactions with the host, are crucial for health. On the other hand, epidemiological and experimental support has also grown for the ‘early programming hypothesis’, according to which factors that act in utero and early in life program the risks for adverse health outcomes later on. The microbiota of the gut develops during infancy, in close interaction with immune development, and with extensive variability across individuals. It follows that the specific process of gut colonization and the microbe-host interactions established in an individual during this period have the potential to represent main determinants of life-long propensity to immune disease. Although much remains to be learnt on the progression of events by which the gut microbiota becomes established and initiates its intimate relationships with the host, and on the long-term repercussions of this process, recent works have advanced significatively in this direction. PMID:25438024

  1. Dihydroartemisinin promotes angiogenesis during the early embryonic development of zebrafish

    PubMed Central

    Ba, Qian; Duan, Juan; Tian, Jia-qiang; Wang, Zi-liang; Chen, Tao; Li, Xiao-guang; Chen, Pei-zhan; Wu, Song-jie; Xiang, Li; Li, Jing-quan; Chu, Rui-ai; Wang, Hui

    2013-01-01

    Aim: To investigate the embryotoxicity of dihydroartemisinin (DHA), the main active metabolite of artemisinin, in zebrafish, and explore the corresponding mechanisms. Methods: The embryos of wild type and TG (flk1:GFP) transgenic zebrafish were exposed to DHA. Developmental phenotypes of the embryos were observed. Development of blood vessels was directly observed in living embryos of TG (flk1:GFP) transgenic zebrafish under fluorescence microscope. The expression of angiogenesis marker genes vegfa, flk1, and flt1 in the embryos was detected using real-time PCR and RNA in situ hybridization assays. Results: Exposure to DHA (1–10 mg/L) dose-dependently caused abnormal zebrafish embryonic phenotypes in the early developmental stage. Furthermore, exposure to DHA (10 mg/L) resulted in more pronounced embryonic angiogenesis in TG (flk1:GFP) zebrafish line. Exposure to DHA (10 mg/L) significantly increased the mRNA expression of vegfa, flk1, and flt1 in the embryos. Knockdown of the flk1 protein partially blocked the effects of DHA on embryogenesis. Conclusion: DHA causes abnormal embryonic phenotypes and promotes angiogenesis in zebrafish early embryonic development, demonstrating the potential embryotoxicity of DHA. PMID:23708556

  2. Early lexical development in Spanish-speaking infants and toddlers.

    PubMed

    Jackson-Maldonado, D; Thal, D; Marchman, V; Bates, E; Gutierrez-Clellen, V

    1993-10-01

    This paper describes the early lexical development of a group of 328 normal Spanish-speaking children aged 0;8 to 2;7. First the development and structure of a new parent report instrument, Inventario del Desarollo de Habilidades Communicativas is described. Then five studies carried out with the instrument are presented. In the first study vocabulary development of Spanish-speaking infants and toddlers is compared to that of English-speaking infants and toddlers. The English data were gathered using a comparable parental report, the MacArthur Communicative Development Inventories. In the second study the general characteristics of Spanish language acquisition, and the effects of various demographic factors on that process, are examined. Study 3 examines the differential effects of three methods of collecting the data (mail-in, personal interview, and clinic waiting room administration). Studies 4 and 5 document the reliability and validity of the instrument. Results show that the trajectories of development are very similar for Spanish- and English-speaking children in this age range, that children from varying social groups develop similarly, and that mail-in and personal interview administration techniques produce comparable results. Inventories administered in a medical clinic waiting room, on the other hand, produced lower estimates of toddler vocabulary than the other two models.

  3. Altered Gravity and Early Heart Development in Culture

    NASA Technical Reports Server (NTRS)

    Wiens, Darrell J.; Lwigale, P.; Denning, J.

    1996-01-01

    The macromolecules comprising the cytoskeleton and extracellular matrix of cells may be sensitive to gravitation. Since early development of organs depends on dynamic interactions across cell surfaces, altered gravity may disturb development. We investigated this possibility for heart development. Previous studies showed that the extracellular matrix glycoprotein fibronectin (Fn) is necessary for normal heart development. We cultured precardiac tissue explants in a high aspect ratio bioreactor vessel (HARV) to simulate microgravity. We observed tissue morphology, contraction, and Fn distribution by immunolocalization in HARV rotated and control (lxg) explants, cultured 18 hr. We also measured Fn amount by immunoassay. Explants in HARV were rotated at 6 rpm to achieve continuous freefall. Thirty-five of 37 control, but only 1 of 37 matched rotated explants exhibited contractions. Tissue architecture was identical. Immunolocalization of Fn showed remarkable differences which may be related to the development of contractions. The Fn staining in the HARV explants was less intense in all areas. Areas of linear staining along epithelia were present but shorter, and there was less intercellular staining in both mesenchymal tissue and myocardium. Initial immunoassay results of 5 matched pairs of explants showed a 22% reduction in total tissue Fn in the HARV rotated samples. Our results indicate that altered gravity in the HARV reduced the amount and distribution of Fn, as assessed by two independent criteria. This was correlated with a reduction in the development of contractile activity.

  4. Cultured normal mammalian tissue and process

    NASA Technical Reports Server (NTRS)

    Goodwin, Thomas J. (Inventor); Prewett, Tacey L. (Inventor); Wolf, David A. (Inventor); Spaulding, Glenn F. (Inventor)

    1993-01-01

    Normal mammalian tissue and the culturing process has been developed for the three groups of organ, structural and blood tissue. The cells are grown in vitro under microgravity culture conditions and form three dimensional cell aggregates with normal cell function. The microgravity culture conditions may be microgravity or simulated microgravity created in a horizontal rotating wall culture vessel.

  5. Electrical Interactions between Mammalian Cortical Neutons

    DTIC Science & Technology

    1990-05-24

    direct responses to acetyl- the entire mammalian central nervous sys- choline and nicotine. Deadvyler and col- teni (19, 32).’The development of...BERT J. (1985) Neurotoxic lesion ; of the athmic neurons recorded near the par-anterior hypothalamus disrupt the JoSentricular in vitro. Brain Res. Bull

  6. Modeling and managing risk early in software development

    NASA Technical Reports Server (NTRS)

    Briand, Lionel C.; Thomas, William M.; Hetmanski, Christopher J.

    1993-01-01

    In order to improve the quality of the software development process, we need to be able to build empirical multivariate models based on data collectable early in the software process. These models need to be both useful for prediction and easy to interpret, so that remedial actions may be taken in order to control and optimize the development process. We present an automated modeling technique which can be used as an alternative to regression techniques. We show how it can be used to facilitate the identification and aid the interpretation of the significant trends which characterize 'high risk' components in several Ada systems. Finally, we evaluate the effectiveness of our technique based on a comparison with logistic regression based models.

  7. Development of a model describing regulation of casein synthesis by the mammalian target of rapamycin (mTOR) signaling pathway in response to insulin, amino acids, and acetate.

    PubMed

    Castro, J J; Arriola Apelo, S I; Appuhamy, J A D R N; Hanigan, M D

    2016-08-01

    To improve dietary protein use efficiency in lactating cows, mammary protein synthesis responses to AA, energy substrates, and hormones must be better understood. These entities exert their effects through stimulation of mRNA translation via control of initiation and elongation rates at the cellular level. A central protein kinase of this phenomenon is the mammalian target of rapamycin (mTOR), which transfers the nutritional and hormonal stimuli onto a series of proteins downstream through a cascade of phosphorylation reactions that ultimately affect protein synthesis. The objective of this work was to further develop an existing mechanistic model of mTOR phosphorylation responses to insulin and total essential AA to include the effects of specific essential AA and acetate mediated by signaling proteins including protein kinase B (Akt), adenosine monophosphate activated protein kinase (AMPK), and mTOR and to add a representation of milk protein synthesis. Data from 6 experiments in MAC-T cells and mammary tissue slices previously conducted in our laboratory were assembled and used to parameterize the dynamic system of differential equations representing Akt, AMPK, and mTOR in their phosphorylated and dephosphorylated states and the resulting regulation of milk protein synthesis. The model predicted phosphorylated Akt, mTOR, AMPK, and casein synthesis rates with root mean square prediction errors of 16.8, 28.4, 33.0, and 54.9%, respectively. All other dependent variables were free of mean and slope bias, indicating an adequate representation of the data. Whereas mTOR was not very sensitive to changes in insulin or acetate levels, it was highly sensitive to leucine and isoleucine, and this signal appeared to be effectively transduced to casein synthesis. Although prior work had observed a relationship with additional essential AA, and data supporting those conclusions were present in the data set, we were unable to derive significant relationships with any essential

  8. Development of two bacterial artificial chromosome shuttle vectors for a recombination-based cloning and regulated expression of large genes in mammalian cells.

    PubMed

    Hong, Y K; Kim, D H; Beletskii, A; Lee, C; Memili, E; Strauss, W M

    2001-04-01

    Most conditional expression vectors designed for mammalian cells have been valuable systems for studying genes of interest by regulating their expressions. The available vectors, however, are reliable for the short-length cDNA clones and not optimal for relatively long fragments of genomic DNA or long cDNAs. Here, we report the construction of two bacterial artificial chromosome (BAC) vectors, capable of harboring large inserts and shuttling among Escherichia coli, yeast, and mammalian cells. These two vectors, pEYMT and pEYMI, contain conditional expression systems which are designed to be regulated by tetracycline and mouse interferons, respectively. To test the properties of the vectors, we cloned in both vectors the green fluorescence protein (GFP) through an in vitro ligation reaction and the 17.8-kb-long X-inactive-specific transcript (Xist) cDNA through homologous recombination in yeast. Subsequently, we characterized their regulated expression properties using real-time quantitative RT-PCR (TaqMan) and RNA-fluorescent in situ hybridization (FISH). We demonstrate that these two BAC vectors are good systems for recombination-based cloning and regulated expression of large genes in mammalian cells. Copyright 2001 Academic Press.

  9. Brain Development and Early Learning: Research on Brain Development. Quality Matters. Volume 1, Winter 2007

    ERIC Educational Resources Information Center

    Edie, David; Schmid, Deborah

    2007-01-01

    For decades researchers have been aware of the extraordinary development of a child's brain during the first five years of life. Recent advances in neuroscience have helped crystallize earlier findings, bringing new clarity and understanding to the field of early childhood brain development. Children are born ready to learn. They cultivate 85…

  10. Development of a Human Neurovascular Unit Organotypic Systems Model of Early Brain Development

    EPA Science Inventory

    The inability to model human brain and blood-brain barrier development in vitro poses a major challenge in studies of how chemicals impact early neurogenic periods. During human development, disruption of thyroid hormone (TH) signaling is related to adverse morphological effects ...

  11. Deuterostome evolution: early development in the enteropneust hemichordate, Ptychodera flava

    NASA Technical Reports Server (NTRS)

    Henry, J. Q.; Tagawa, K.; Martindale, M. Q.

    2001-01-01

    Molecular and morphological comparisons indicate that the Echinodermata and Hemichordata represent closely related sister-phyla within the Deuterostomia. Much less is known about the development of the hemichordates compared to other deuterostomes. For the first time, cell lineage analyses have been carried out for an indirect-developing representative of the enteropneust hemichordates, Ptychodera flava. Single blastomeres were iontophoretically labeled with Dil at the 2- through 16-cell stages, and their fates followed through development to the tornaria larval stage. The early cleavage pattern of P. flava is similar to that of the direct-developing hemichordate, Saccoglossus kowalevskii, as well as that displayed by indirect-developing echinoids. The 16-celled embryo contains eight animal "mesomeres," four slightly larger "macromeres," and four somewhat smaller vegetal "micromeres." The first cleavage plane was not found to bear one specific relationship relative to the larval dorsoventral axis. Although individual blastomeres generate discrete clones of cells, the appearance and exact locations of these clones are variable with respect to the embryonic dorsoventral and bilateral axes. The eight animal mesomeres generate anterior (animal) ectoderm of the larva, which includes the apical organ; however, contributions to the apical organ were found to be variable as only a subset of the animal blastomeres end up contributing to its formation and this varies from embryo to embryo. The macromeres generate posterior larval ectoderm, and the vegetal micromeres form all the internal, endomesodermal tissues. These blastomere contributions are similar to those found during development of the only other hemichordate studied, the direct-developing enteropneust, S. kowalevskii. Finally, isolated blastomeres prepared at either the two- or the four-cell stage are capable of forming normal-appearing, miniature tornaria larvae. These findings indicate that the fates of these

  12. GATA-3 is required for early T lineage progenitor development

    PubMed Central

    Hosoya, Tomonori; Kuroha, Takashi; Moriguchi, Takashi; Cummings, Dustin; Maillard, Ivan; Lim, Kim-Chew

    2009-01-01

    Most T lymphocytes appear to arise from very rare early T lineage progenitors (ETPs) in the thymus, but the transcriptional programs that specify ETP generation are not completely known. The transcription factor GATA-3 is required for the development of T lymphocytes at multiple late differentiation steps as well as for the development of thymic natural killer cells. However, a role for GATA-3 before the double-negative (DN) 3 stage of T cell development has to date been obscured both by the developmental heterogeneity of DN1 thymocytes and the paucity of ETPs. We provide multiple lines of in vivo evidence through the analysis of T cell development in Gata3 hypomorphic mutant embryos, in irradiated mice reconstituted with Gata3 mutant hematopoietic cells, and in mice conditionally ablated for the Gata3 gene to show that GATA-3 is required for ETP generation. We further show that Gata3 loss does not affect hematopoietic stem cells or multipotent hematopoietic progenitors. Finally, we demonstrate that Gata3 mutant lymphoid progenitors exhibit neither increased apoptosis nor diminished cell-cycle progression. Thus, GATA-3 is required for the cell-autonomous development of the earliest characterized thymic T cell progenitors. PMID:19934022

  13. Changes in Acetyl CoA Levels during the Early Embryonic Development of Xenopus laevis

    PubMed Central

    Tsuchiya, Yugo; Pham, Uyen; Hu, Wanzhou; Ohnuma, Shin-ichi; Gout, Ivan

    2014-01-01

    Coenzyme A (CoA) is a ubiquitous and fundamental intracellular cofactor. CoA acts as a carrier of metabolically important carboxylic acids in the form of CoA thioesters and is an obligatory component of a multitude of catabolic and anabolic reactions. Acetyl CoA is a CoA thioester derived from catabolism of all major carbon fuels. This metabolite is at a metabolic crossroads, either being further metabolised as an energy source or used as a building block for biosynthesis of lipids and cholesterol. In addition, acetyl CoA serves as the acetyl donor in protein acetylation reactions, linking metabolism to protein post-translational modifications. Recent studies in yeast and cultured mammalian cells have suggested that the intracellular level of acetyl CoA may play a role in the regulation of cell growth, proliferation and apoptosis, by affecting protein acetylation reactions. Yet, how the levels of this metabolite change in vivo during the development of a vertebrate is not known. We measured levels of acetyl CoA, free CoA and total short chain CoA esters during the early embryonic development of Xenopus laevis using HPLC. Acetyl CoA and total short chain CoA esters start to increase around midblastula transition (MBT) and continue to increase through stages of gastrulation, neurulation and early organogenesis. Pre-MBT embryos contain more free CoA relative to acetyl CoA but there is a shift in the ratio of acetyl CoA to CoA after MBT, suggesting a metabolic transition that results in net accumulation of acetyl CoA. At the whole-embryo level, there is an apparent correlation between the levels of acetyl CoA and levels of acetylation of a number of proteins including histones H3 and H2B. This suggests the level of acetyl CoA may be a factor, which determines the degree of acetylation of these proteins, hence may play a role in the regulation of embryogenesis. PMID:24831956

  14. Short National Early Warning Score - Developing a Modified Early Warning Score.

    PubMed

    Luís, Leandro; Nunes, Carla

    2017-12-11

    Early Warning Score (EWS) systems have been developed for detecting hospital patients clinical deterioration. Many studies show that a National Early Warning Score (NEWS) performs well in discriminating survival from death in acute medical and surgical hospital wards. NEWS is validated for Portugal and is available for use. A simpler EWS system may help to reduce the risk of error, as well as increase clinician compliance with the tool. The aim of the study was to evaluate whether a simplified NEWS model will improve use and data collection. We evaluated the ability of single and aggregated parameters from the NEWS model to detect patients' clinical deterioration in the 24h prior to an outcome. There were 2 possible outcomes: Survival vs Unanticipated intensive care unit admission or death. We used binary logistic regression models and Receiver Operating Characteristic Curves (ROC) to evaluate the parameters' performance in discriminating among the outcomes for a sample of patients from 6 Portuguese hospital wards. NEWS presented an excellent discriminating capability (Area under the Curve of ROC (AUCROC)=0.944). Temperature and systolic blood pressure (SBP) parameters did not contribute significantly to the model. We developed two different models, one without temperature, and the other by removing temperature and SBP (M2). Both models had an excellent discriminating capability (AUCROC: 0.965; 0.903, respectively) and a good predictive power in the optimum threshold of the ROC curve. The 3 models revealed similar discriminant capabilities. Although the use of SBP is not clearly evident in the identification of clinical deterioration, it is recognized as an important vital sign. We recommend the use of the first new model, as its simplicity may help to improve adherence and use by health care workers. Copyright © 2017 Australian College of Critical Care Nurses Ltd. Published by Elsevier Ltd. All rights reserved.

  15. Early motor development and cognitive abilities among Mexican preschoolers.

    PubMed

    Osorio-Valencia, Erika; Torres-Sánchez, Luisa; López-Carrillo, Lizbeth; Rothenberg, Stephen J; Schnaas, Lourdes

    2017-07-18

    Psychomotricity plays a very important role in children's development, especially for learning involving reading-writing and mathematical calculations. Evaluate motor development in children 3 years old and its relationship with their cognitive abilities at the age of 5 years. Based on a cohort study, we analyzed the information about motor performance evaluated at 3 years old by Peabody Motor Scale and cognitive abilities at 5 years old. The association was estimated using linear regression models adjusted by mother's intelligence quotient, sex, Bayley mental development index at 18 months, and quality of the environment at home (HOME scale). 148 children whose motor performance was determined at age 3 and was evaluated later at age 5 to determine their cognitive abilities. Cognitive abilities (verbal, quantitative, and memory) measured by McCarthy Scales. Significant positive associations were observed between stationary balance at age 3 with verbal abilities (β = 0.67, p = .04) and memory (β = 0.81, p = .02) at 5 years. Grasping and visual-motor integration were significant and positively associated with quantitative abilities (β = 0.74, p = .005; β = 0.61, p = .01) and memory (β = 2.11, p = .001; β = 1.74, p = .004). The results suggest that early motor performance contributes to the establishment of cognitive abilities at 5 years. Evaluation and early motor stimulation before the child is faced with formal learning likely helps to create neuronal networks that facilitate the acquisition of academic knowledge.

  16. Development of Mechanochemically Active Polymers for Early Damage Detection

    NASA Astrophysics Data System (ADS)

    Zou, Jin

    Identification of early damage in polymer composite materials is of significant importance so that preventative measures can be taken before the materials reach catastrophic failure. Scientists have been developing damage detection technologies over many years and recently, mechanophore-based polymers, in which mechanical energy is translated to activate a chemical transformation, have received increasing attention. More specifically, the damage can be made detectable by mechanochromic polymers, which provide a visible color change upon the scission of covalent bonds under stress. This dissertation focuses on the study of a novel self-sensing framework for identifying early and in-situ damage by employing unique stress-sensing mechanophores. Two types of mechanophores, cyclobutane and cyclooctane, were utilized, and the former formed from cinnamoyl moeities and the latter formed from anthracene upon photodimerization. The effects on the thermal and mechanical properties with the addition of the cyclobutane-based polymers into epoxy matrices were investigated. The emergence of cracks was detected by fluorescent signals at a strain level right after the yield point of the polymer blends, and the fluorescence intensified with the accumulation of strain. Similar to the mechanism of fluorescence emission from the cleavage of cyclobutane, the cyclooctane moiety generated fluorescent emission with a higher quantum yield upon cleavage. The experimental results also demonstrated the success of employing the cyclooctane type mechanophore as a potential force sensor, as the fluorescence intensification was correlated with the strain increase.

  17. Investigational drugs in early development for treating dengue infection.

    PubMed

    Beesetti, Hemalatha; Khanna, Navin; Swaminathan, Sathyamangalam

    2016-09-01

    Dengue has emerged as the most significant arboviral disease of the current century. A drug for dengue is an urgent unmet need. As conventional drug discovery efforts have not produced any promising clinical candidates, there is a shift toward re-positioning pre-existing drugs for dengue to fast-track dengue drug development. This article provides an update on the current status of recently completed and ongoing dengue drug trials. All dengue drug trials described in this article were identified from a list of >230 trials that were returned upon searching the World Health Organization's International Clinical Trials Registry Platform web portal using the search term 'dengue' on December 31(st), 2015. None of the handful of drugs tested so far has yielded encouraging results. Early trial experience has served to emphasize the challenge of drug testing in the short therapeutic time window available, the need for tools to predict 'high-risk' patients early on and the limitations of the existing pre-clinical model systems. Significant investment of efforts and resources is a must before the availability of a safe, effective and inexpensive dengue drug becomes a reality. Currently, supportive fluid therapy remains the only option available for dengue treatment.

  18. Measuring the implementation of early childhood development programs.

    PubMed

    Aboud, Frances E; Prado, Elizabeth L

    2018-05-01

    In this paper we describe ways to measure variables of interest when evaluating the implementation of a program to improve early childhood development (ECD). The variables apply to programs delivered to parents in group sessions and home or clinic visits, as well as in early group care for children. Measurements for four categories of variables are included: training and assessment of delivery agents and supervisors; program features such as quality of delivery, reach, and dosage; recipients' acceptance and enactment; and stakeholders' engagement. Quantitative and qualitative methods are described, along with when measures might be taken throughout the processes of planning, preparing, and implementing. A few standard measures are available, along with others that researchers can select and modify according to their goals. Descriptions of measures include who might collect the information, from whom, and when, along with how information might be analyzed and findings used. By converging on a set of common methods to measure implementation variables, investigators can work toward improving programs, identifying gaps that impede the scalability and sustainability of programs, and, over time, ascertain program features that lead to successful outcomes. © 2018 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals, Inc. on behalf of New York Academy of Sciences.

  19. Early Miocene sequence development across the New Jersey margin

    USGS Publications Warehouse

    Monteverde, D.H.; Mountain, Gregory S.; Miller, K.G.

    2008-01-01

    Sequence stratigraphy provides an understanding of the interplay between eustasy, sediment supply and accommodation in the sedimentary construction of passive margins. We used this approach to follow the early to middle Miocene growth of the New Jersey margin and analyse the connection between relative changes of sea level and variable sediment supply. Eleven candidate sequence boundaries were traced in high-resolution multi-channel seismic profiles across the inner margin and matched to geophysical log signatures and lithologic changes in ODP Leg 150X onshore coreholes. Chronologies at these drill sites were then used to assign ages to the intervening seismic sequences. We conclude that the regional and global correlation of early Miocene sequences suggests a dominant role of global sea-level change but margin progradation was controlled by localized sediment contribution and that local conditions played a large role in sequence formation and preservation. Lowstand deposits were regionally restricted and their locations point to both single and multiple sediment sources. The distribution of highstand deposits, by contrast, documents redistribution by along shelf currents. We find no evidence that sea level fell below the elevation of the clinoform rollover, and the existence of extensive lowstand deposits seaward of this inflection point indicates efficient cross-shelf sediment transport mechanisms despite the apparent lack of well-developed fluvial drainage. ?? 2008 The Authors. Journal compilation ?? 2008 Blackwell Publishing.

  20. Producing Newborn Synchronous Mammalian Cells

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R.; Helmstetter, Charles E.; Thornton, Maureen

    2008-01-01

    A method and bioreactor for the continuous production of synchronous (same age) population of mammalian cells have been invented. The invention involves the attachment and growth of cells on an adhesive-coated porous membrane immersed in a perfused liquid culture medium in a microgravity analog bioreactor. When cells attach to the surface divide, newborn cells are released into the flowing culture medium. The released cells, consisting of a uniform population of synchronous cells are then collected from the effluent culture medium. This invention could be of interest to researchers investigating the effects of the geneotoxic effects of the space environment (microgravity, radiation, chemicals, gases) and to pharmaceutical and biotechnology companies involved in research on aging and cancer, and in new drug development and testing.

  1. Asymmetrical Interhemispheric Connections Develop in Cat Visual Cortex after Early Unilateral Convergent Strabismus: Anatomy, Physiology, and Mechanisms

    PubMed Central

    Bui Quoc, Emmanuel; Ribot, Jérôme; Quenech’Du, Nicole; Doutremer, Suzette; Lebas, Nicolas; Grantyn, Alexej; Aushana, Yonane; Milleret, Chantal

    2011-01-01

    In the mammalian primary visual cortex, the corpus callosum contributes to the unification of the visual hemifields that project to the two hemispheres. Its development depends on visual experience. When this is abnormal, callosal connections must undergo dramatic anatomical and physiological changes. However, data concerning these changes are sparse and incomplete. Thus, little is known about the impact of abnormal postnatal visual experience on the development of callosal connections and their role in unifying representation of the two hemifields. Here, the effects of early unilateral convergent strabismus (a model of abnormal visual experience) were fully characterized with respect to the development of the callosal connections in cat visual cortex, an experimental model for humans. Electrophysiological responses and 3D reconstruction of single callosal axons show that abnormally asymmetrical callosal connections develop after unilateral convergent strabismus, resulting from an extension of axonal branches of specific orders in the hemisphere ipsilateral to the deviated eye and a decreased number of nodes and terminals in the other (ipsilateral to the non-deviated eye). Furthermore this asymmetrical organization prevents the establishment of a unifying representation of the two visual hemifields. As a general rule, we suggest that crossed and uncrossed retino-geniculo-cortical pathways contribute successively to the development of the callosal maps in visual cortex. PMID:22275883

  2. Longitudinal development of prefrontal function during early childhood.

    PubMed

    Moriguchi, Yusuke; Hiraki, Kazuo

    2011-04-01

    This is a longitudinal study on development of prefrontal function in young children. Prefrontal areas have been observed to develop dramatically during early childhood. To elucidate this development, we gave children cognitive shifting tasks related to prefrontal function at 3 years of age (Time 1) and 4 years of age (Time 2). We then monitored developmental changes in behavioral performance and examined prefrontal activation using near infrared spectroscopy. We found that children showed better behavioral performance and significantly stronger inferior prefrontal activation at Time 2 than they did at Time 1. Moreover, we demonstrated individual differences in prefrontal activation for the same behavioral tasks. Children who performed better in tasks at Time 1 showed significant activation of the right inferior prefrontal regions at Time 1 and significant activation of the bilateral inferior prefrontal regions at Time 2. Children who showed poorer performance at Time 1 exhibited no significant inferior prefrontal activation at Time 1 but significant left inferior prefrontal activation at Time 2. These results indicate the importance of the longitudinal method to address the link between cognitive and neural development. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. The development of phonological skills in late and early talkers

    PubMed Central

    KEHOE, Margaret; CHAPLIN, Elisa; MUDRY, Pauline; FRIEND, Margaret

    2016-01-01

    This study examined the relationship between phonological and lexical development in a group of French-speaking children (n=30), aged 29 months. The participants were divided into three sub-groups based on the number of words in their expressive vocabulary : low vocabulary (below the 15th percentile) (<< late-talkers >>) ; average-sized vocabulary (40-60th percentile) (<< middle group >>) and advanced vocabulary (above the 90th percentile) (<< precocious >> or “early talkers”). The phonological abilities (e.g., phonemic inventory, percentage of correct consonants, and phonological processes) of the three groups were compared. The comparison was based on analyses of spontaneous language samples. Most findings were consistent with previous results found in English-speaking children, indicating that the phonological abilities of late talkers are less well developed than those of children with average-sized vocabularies which in turn are less well-developed than those of children with advanced vocabularies. Nevertheless, several phonological measures were not related to vocabulary size, in particular those concerning syllable-final position. These findings differ from those obtained in English. The article finally discusses the clinical implications of the findings for children with delayed language development. PMID:26924855

  4. Oligodendrocytes as Regulators of Neuronal Networks during Early Postnatal Development

    PubMed Central

    Ramos, Maria; Ikrar, Taruna; Kinoshita, Chisato; De Mei, Claudia; Tirotta, Emanuele; Xu, Xiangmin; Borrelli, Emiliana

    2011-01-01

    Oligodendrocytes are the glial cells responsible for myelin formation. Myelination occurs during the first postnatal weeks and, in rodents, is completed during the third week after birth. Myelin ensures the fast conduction of the nerve impulse; in the adult, myelin proteins have an inhibitory role on axon growth and regeneration after injury. During brain development, oligodendrocytes precursors originating in multiple locations along the antero-posterior axis actively proliferate and migrate to colonize the whole brain. Whether the initial interactions between oligodendrocytes and neurons might play a functional role before the onset of myelination is still not completely elucidated. In this article, we addressed this question by transgenically targeted ablation of proliferating oligodendrocytes during cerebellum development. Interestingly, we show that depletion of oligodendrocytes at postnatal day 1 (P1) profoundly affects the establishment of cerebellar circuitries. We observed an impressive deregulation in the expression of molecules involved in axon growth, guidance and synaptic plasticity. These effects were accompanied by an outstanding increase of neurofilament staining observed 4 hours after the beginning of the ablation protocol, likely dependent from sprouting of cerebellar fibers. Oligodendrocyte ablation modifies localization and function of ionotropic glutamate receptors in Purkinje neurons. These results show a novel oligodendrocyte function expressed during early postnatal brain development, where these cells participate in the formation of cerebellar circuitries, and influence its development. PMID:21589880

  5. Brain anatomical networks in early human brain development.

    PubMed

    Fan, Yong; Shi, Feng; Smith, Jeffrey Keith; Lin, Weili; Gilmore, John H; Shen, Dinggang

    2011-02-01

    Recent neuroimaging studies have demonstrated that human brain networks have economic small-world topology and modular organization, enabling efficient information transfer among brain regions. However, it remains largely unknown how the small-world topology and modular organization of human brain networks emerge and develop. Using longitudinal MRI data of 28 healthy pediatric subjects, collected at their ages of 1 month, 1 year, and 2 years, we analyzed development patterns of brain anatomical networks derived from morphological correlations of brain regional volumes. The results show that the brain network of 1-month-olds has the characteristically economic small-world topology and nonrandom modular organization. The network's cost efficiency increases with the brain development to 1 year and 2 years, so does the modularity, providing supportive evidence for the hypothesis that the small-world topology and the modular organization of brain networks are established during early brain development to support rapid synchronization and information transfer with minimal rewiring cost, as well as to balance between local processing and global integration of information. Copyright © 2010. Published by Elsevier Inc.

  6. Mechanical origins of rightward torsion in early chick brain development

    NASA Astrophysics Data System (ADS)

    Chen, Zi; Guo, Qiaohang; Dai, Eric; Taber, Larry

    2015-03-01

    During early development, the neural tube of the chick embryo undergoes a combination of progressive ventral bending and rightward torsion. This torsional deformation is one of the major organ-level left-right asymmetry events in development. Previous studies suggested that bending is mainly due to differential growth, however, the mechanism for torsion remains poorly understood. Since the heart almost always loops rightwards that the brain twists, researchers have speculated that heart looping affects the direction of brain torsion. However, direct evidence is lacking, nor is the mechanical origin of such torsion understood. In our study, experimental perturbations show that the bending and torsional deformations in the brain are coupled and that the vitelline membrane applies an external load necessary for torsion to occur. Moreover, the asymmetry of the looping heart gives rise to the chirality of the twisted brain. A computational model and a 3D printed physical model are employed to help interpret these findings. Our work clarifies the mechanical origins of brain torsion and the associated left-right asymmetry, and further reveals that the asymmetric development in one organ can induce the asymmetry of another developing organ through mechanics, reminiscent of D'Arcy Thompson's view of biological form as ``diagram of forces''. Z.C. is supported by the Society in Science - Branco Weiss fellowship, administered by ETH Zurich. L.A.T acknowledges the support from NIH Grants R01 GM075200 and R01 NS070918.

  7. Probable influence of early Carboniferous (Tournaisian-early Visean) geography on the development of Waulsortian and Waulsortian-like mounds

    NASA Astrophysics Data System (ADS)

    King, David T., Jr.

    1990-07-01

    All of the known Tournaisian-early Visean (ca. 360-348 Ma) age carbonate mud mounds (Waulsortian and Waulsortian-like mounds) developed in low paleolatitudes on the southern shelf margin of Laurussia and in the Laurussian interior seaway. The Tournaisian-early Visean geography probably prevented hurricanes, tropical storms, and winter storms from crossing the shelf margin or interior seaway where these mounds developed. Implications of the lack of storm energy on mound development are discussed.

  8. Investing in the foundation of sustainable development: pathways to scale up for early childhood development.

    PubMed

    Richter, Linda M; Daelmans, Bernadette; Lombardi, Joan; Heymann, Jody; Boo, Florencia Lopez; Behrman, Jere R; Lu, Chunling; Lucas, Jane E; Perez-Escamilla, Rafael; Dua, Tarun; Bhutta, Zulfiqar A; Stenberg, Karin; Gertler, Paul; Darmstadt, Gary L

    2017-01-07

    Building on long-term benefits of early intervention (Paper 2 of this Series) and increasing commitment to early childhood development (Paper 1 of this Series), scaled up support for the youngest children is essential to improving health, human capital, and wellbeing across the life course. In this third paper, new analyses show that the burden of poor development is higher than estimated, taking into account additional risk factors. National programmes are needed. Greater political prioritisation is core to scale-up, as are policies that afford families time and financial resources to provide nurturing care for young children. Effective and feasible programmes to support early child development are now available. All sectors, particularly education, and social and child protection, must play a role to meet the holistic needs of young children. However, health provides a critical starting point for scaling up, given its reach to pregnant women, families, and young children. Starting at conception, interventions to promote nurturing care can feasibly build on existing health and nutrition services at limited additional cost. Failure to scale up has severe personal and social consequences. Children at elevated risk for compromised development due to stunting and poverty are likely to forgo about a quarter of average adult income per year, and the cost of inaction to gross domestic product can be double what some countries currently spend on health. Services and interventions to support early childhood development are essential to realising the vision of the Sustainable Development Goals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Investing in the foundation of sustainable development: pathways to scale up for early childhood development

    PubMed Central

    Richter, Linda M; Daelmans, Bernadette; Lombardi, Joan; Heymann, Jody; Boo, Florencia Lopez; Behrman, Jere R; Lu, Chunling; Lucas, Jane E; Perez-Escamilla, Rafael; Dua, Tarun; Bhutta, Zulfiqar A; Stenberg, Karin; Gertler, Paul; Darmstadt, Gary L

    2018-01-01

    Building on long-term benefits of early intervention (Paper 2 of this Series) and increasing commitment to early childhood development (Paper 1 of this Series), scaled up support for the youngest children is essential to improving health, human capital, and wellbeing across the life course. In this third paper, new analyses show that the burden of poor development is higher than estimated, taking into account additional risk factors. National programmes are needed. Greater political prioritisation is core to scale-up, as are policies that afford families time and financial resources to provide nurturing care for young children. Effective and feasible programmes to support early child development are now available. All sectors, particularly education, and social and child protection, must play a role to meet the holistic needs of young children. However, health provides a critical starting point for scaling up, given its reach to pregnant women, families, and young children. Starting at conception, interventions to promote nurturing care can feasibly build on existing health and nutrition services at limited additional cost. Failure to scale up has severe personal and social consequences. Children at elevated risk for compromised development due to stunting and poverty are likely to forgo about a quarter of average adult income per year, and the cost of inaction to gross domestic product can be double what some countries currently spend on health. Services and interventions to support early childhood development are essential to realising the vision of the Sustainable Development Goals. PMID:27717610

  10. Late Cretaceous-Early Palaeogene tectonic development of SE Asia

    NASA Astrophysics Data System (ADS)

    Morley, C. K.

    2012-10-01

    The Late Cretaceous-Early Palaeogene history of the continental core of SE Asia (Sundaland) marks the time prior to collision of India with Asia when SE Asia, from the Tethys in the west to the Palaeo-Pacific in the east, lay in the upper plate of subduction zones. In Myanmar and Sumatra, subduction was interrupted in the Aptian-Albian by a phase of arc accretion (Woyla and Mawgyi arcs) and in Java, eastern Borneo and Western Sulawesi by collision of continental fragments rifted from northern Australia. Subsequent resumption of subduction in the Myanmar-Thailand sector explains: 1) early creation of oceanic crust in the Andaman Sea in a supra-subduction zone setting ~ 95 Ma, 2) the belt of granite plutons of Late Cretaceous-Early Palaeogene age (starting ~ 88 Ma) in western Thailand and central Myanmar, and 3) amphibolite grade metamorphism between 70 and 80 Ma seen in gneissic outcrops in western and central Thailand, and 4) accretionary prism development in the Western Belt of Myanmar, until glancing collision with the NE corner of Greater India promoted ophiolite obduction, deformation and exhumation of marine sediments in the early Palaeogene. The Ranong strike-slip fault and other less well documented faults, were episodically active during the Late Cretaceous-Palaeogene time. N to NW directed subduction of the Palaeo-Pacific ocean below Southern China, Vietnam and Borneo created a major magmatic arc, associated with rift basins, metamorphic core complexes and strike-slip deformation which continued into the Late Cretaceous. The origin and timing of termination of subduction has recently been explained by collision of a large Luconia continental fragment either during the Late Cretaceous or Palaeogene. Evidence for such a collision is absent from the South China Sea well and seismic reflection record and here collision is discounted. Instead relocation of the subducting margin further west, possibly in response of back-arc extension (which created the Proto

  11. The quantum defect: Early history and recent developments

    SciTech Connect

    Rau, A.R.; Inokuti, M.

    1997-03-01

    The notion of the quantum defect is important in atomic and molecular spectroscopy and also in unifying spectroscopy with collision theory. In the latter context, the quantum defect may be viewed as an ancestor of the phase shift. However, the origin of the term {open_quotes}quantum defect{close_quotes} does not seem to be explained in standard textbooks. It occurred in a 1921 paper by Schr{umlt o}dinger, preceding quantum mechanics, yet giving the correct meaning as an index of the short-range interactions with the core of an atom. We present the early history of the quantum-defect idea, and sketch its recent developments. {copyright}more » {ital 1997 American Association of Physics Teachers.}« less

  12. Nuclear lamins during gametogenesis, fertilization and early development

    NASA Technical Reports Server (NTRS)

    Maul, G. G.; Schatten, G.

    1986-01-01

    The distribution of lamins (described by Gerace, 1978, as major proteins of nuclear envelope) during gametogenesis, fertilization, and early development was investigated in germ cells of a mouse (Mus musculus), an echinoderm (Lytechinus variegatus), and the surf clam (Spisula solidissima) was investigated in order to determine whether the differences detected could be correlated with differences in the function of cells in these stages of the germ cells. In order to monitor the behavior of lamins, the gametes and embryos were labeled with antibodies to lamins A, C, and B extracted from autoimmune sera of patients with scleroderma and Lupus erythematosus. Results indicated that lamin B could be identified in nuclear envelopes on only those nuclei where chromatin is attached and where RNA synthesis takes place.

  13. Exploring Parental Involvement in Early Years Education in China: Development and Validation of the Chinese Early Parental Involvement Scale (CEPIS)

    ERIC Educational Resources Information Center

    Lau, Eva Yi Hung; Li, Hui; Rao, Nirmala

    2012-01-01

    This study developed and validated an instrument, the Chinese Early Parental Involvement Scale (CEPIS), that can be widely used in both local and international contexts to assess Chinese parental involvement in early childhood education. The study was carried out in two stages: (1) focus group interviews were conducted with 41 teachers and 35…

  14. Ethnic Group Differences in Early Head Start Parents Parenting Beliefs and Practices and Links to Children's Early Cognitive Development

    ERIC Educational Resources Information Center

    Keels, Micere

    2009-01-01

    Data from the Early Head Start Research and Evaluation study were used to examine the extent to which several factors mediate between- and within-ethnic-group differences in parenting beliefs and behaviors, and children's early cognitive development (analysis sample of 1198 families). The findings indicate that Hispanic-, European-, and…

  15. The Legacy of Early Experiences in Development: Formalizing Alternative Models of How Early Experiences Are Carried Forward over Time

    ERIC Educational Resources Information Center

    Fraley, R. Chris; Roisman, Glenn I.; Haltigan, John D.

    2013-01-01

    Psychologists have long debated the role of early experience in social and cognitive development. However, traditional approaches to studying this issue are not well positioned to address this debate. The authors present simulations that indicate that the associations between early experiences and later outcomes should approach different…

  16. Documenting with Early Childhood Education Teachers: Pedagogical Documentation as a Tool for Developing Early Childhood Pedagogy and Practises

    ERIC Educational Resources Information Center

    Rintakorpi, Kati

    2016-01-01

    The Finnish social pedagogical curriculum for early childhood education directs early childhood teachers to use documentation to assess and develop pedagogy and practise. This empirical study examines the challenges and benefits a group of Finnish preschool teachers experienced when they learned to document their work. Although the idea of…

  17. Improving Latino Children's Early Language and Literacy Development: Key Features of Early Childhood Education within Family Literacy Programmes

    ERIC Educational Resources Information Center

    Jung, Youngok; Zuniga, Stephen; Howes, Carollee; Jeon, Hyun-Joo; Parrish, Deborah; Quick, Heather; Manship, Karen; Hauser, Alison

    2016-01-01

    Noting the lack of research on how early childhood education (ECE) programmes within family literacy programmes influence Latino children's early language and literacy development, this study examined key features of ECE programmes, specifically teacher-child interactions and child engagement in language and literacy activities and how these…

  18. Crossroads between Bacterial and Mammalian Glycosyltransferases

    PubMed Central

    Brockhausen, Inka

    2014-01-01

    Bacterial glycosyltransferases (GT) often synthesize the same glycan linkages as mammalian GT; yet, they usually have very little sequence identity. Nevertheless, enzymatic properties, folding, substrate specificities, and catalytic mechanisms of these enzyme proteins may have significant similarity. Thus, bacterial GT can be utilized for the enzymatic synthesis of both bacterial and mammalian types of complex glycan structures. A comparison is made here between mammalian and bacterial enzymes that synthesize epitopes found in mammalian glycoproteins, and those found in the O antigens of Gram-negative bacteria. These epitopes include Thomsen–Friedenreich (TF or T) antigen, blood group O, A, and B, type 1 and 2 chains, Lewis antigens, sialylated and fucosylated structures, and polysialic acids. Many different approaches can be taken to investigate the substrate binding and catalytic mechanisms of GT, including crystal structure analyses, mutations, comparison of amino acid sequences, NMR, and mass spectrometry. Knowledge of the protein structures and functions helps to design GT for specific glycan synthesis and to develop inhibitors. The goals are to develop new strategies to reduce bacterial virulence and to synthesize vaccines and other biologically active glycan structures. PMID:25368613

  19. Early Programming by Protein Intake: The Effect of Protein on Adiposity Development and the Growth and Functionality of Vital Organs

    PubMed Central

    Luque, Veronica; Closa-Monasterolo, Ricardo; Escribano, Joaquín; Ferré, Natalia

    2015-01-01

    This article reviews the role of protein intake on metabolic programming early in life. The observations that breastfeeding in infancy reduces the risk of being overweight and obese later in life and the differences in the protein content between formula milk and human milk have generated the early protein hypothesis. The present review focuses on a mechanistic approach to programmed adiposity and the growth and development of other organs by protein intake in infancy, which may be mediated by branched-chain amino acids, insulin, and insulin-like growth factor 1 via the mammalian target of rapamycin. Observational studies and clinical trials have shown that lowering the protein content in infant and follow-on formulas may reduce the risk of becoming obese later in life. The recent body of evidence is currently being translated into new policies. Therefore, the evolution of European regulatory laws and recommendations by expert panels on the protein content of infant and follow-on formulas are also reviewed. Research gaps, such as the critical window for programming adiposity by protein intake, testing formulas with modified amino acids, and the long-term consequences of differences in protein intake on organ functionality among well-nourished infants, have been identified. PMID:27013888

  20. Development of global cortical networks in early infancy.

    PubMed

    Homae, Fumitaka; Watanabe, Hama; Otobe, Takayuki; Nakano, Tamami; Go, Tohshin; Konishi, Yukuo; Taga, Gentaro

    2010-04-07

    Human cognition and behaviors are subserved by global networks of neural mechanisms. Although the organization of the brain is a subject of interest, the process of development of global cortical networks in early infancy has not yet been clarified. In the present study, we explored developmental changes in these networks from several days to 6 months after birth by examining spontaneous fluctuations in brain activity, using multichannel near-infrared spectroscopy. We set up 94 measurement channels over the frontal, temporal, parietal, and occipital regions of the infant brain. The obtained signals showed complex time-series properties, which were characterized as 1/f fluctuations. To reveal the functional connectivity of the cortical networks, we calculated the temporal correlations of continuous signals between all the pairs of measurement channels. We found that the cortical network organization showed regional dependency and dynamic changes in the course of development. In the temporal, parietal, and occipital regions, connectivity increased between homologous regions in the two hemispheres and within hemispheres; in the frontal regions, it decreased progressively. Frontoposterior connectivity changed to a "U-shaped" pattern within 6 months: it decreases from the neonatal period to the age of 3 months and increases from the age of 3 months to the age of 6 months. We applied cluster analyses to the correlation coefficients and showed that the bilateral organization of the networks begins to emerge during the first 3 months of life. Our findings suggest that these developing networks, which form multiple clusters, are precursors of the functional cerebral architecture.

  1. Napping facilitates word learning in early lexical development.

    PubMed

    Horváth, Klára; Myers, Kyle; Foster, Russell; Plunkett, Kim

    2015-10-01

    Little is known about the role that night-time sleep and daytime naps play in early cognitive development. Our aim was to investigate how napping affects word learning in 16-month-olds. Thirty-four typically developing infants were assigned randomly to nap and wake groups. After teaching two novel object-word pairs to infants, we tested their initial performance with an intermodal preferential looking task in which infants are expected to increase their target looking time compared to a distracter after hearing its auditory label. A second test session followed after approximately a 2-h delay. The delay contained sleep for the nap group or no sleep for the wake group. Looking behaviour was measured with an automatic eye-tracker. Vocabulary size was assessed using the Oxford Communicative Development Inventory. A significant interaction between group and session was found in preferential looking towards the target picture. The performance of the nap group increased after the nap, whereas that of the wake group did not change. The gain in performance correlated positively with the expressive vocabulary size in the nap group. These results indicate that daytime napping helps consolidate word learning in infancy. © 2015 European Sleep Research Society.

  2. Recent early clinical drug development for acute kidney injury.

    PubMed

    Gallagher, Kevin M; O'neill, Stephen; Harrison, Ewen M; Ross, James A; Wigmore, Stephen J; Hughes, Jeremy

    2017-02-01

    Despite significant need and historical trials, there are no effective drugs in use for the prevention or treatment of acute kidney injury (AKI). There are several promising agents in early clinical development for AKI and two trials have recently been terminated. There are also exciting new findings in pre-clinical AKI research. There is a need to take stock of current progress in the field to guide future drug development for AKI. Areas covered: The main clinical trial registries, PubMed and pharmaceutical company website searches were used to extract the most recent clinical trials for sterile, transplant and sepsis-associated AKI. We summarise the development of the agents recently in clinical trial, update on their trial progress, consider reasons for failed efficacy of two agents, and discuss new paradigms in pre-clinical targets for AKI. Agents covered include- QPI-1002, THR-184, BB-3, heme arginate, human recombinant alkaline phosphatase (recAP), ciclosporin A, AB103, levosimendan, AC607 and ABT-719. Expert opinion: Due to the heterogenous nature of AKI, agents with the widest pleiotropic effects on multiple pathophysiological pathways are likely to be most effective. Linking preclinical models to clinical indication and improving AKI definition and diagnosis are key areas for improvement in future clinical trials.

  3. The obesogenic effect of high fructose exposure during early development

    PubMed Central

    Goran, Michael I.; Dumke, Kelly; Bouret, Sebastien G.; Kayser, Brandon; Walker, Ryan W.; Blumberg, Bruce

    2016-01-01

    Obesogens are compounds that disrupt the function and development of adipose tissue or the normal metabolism of lipids, leading to an increased risk of obesity and associated diseases. Evidence for the adverse effects of industrial and agricultural obesogens, such as tributyltin, bisphenol A and other organic pollutants is well-established. Current evidence suggests that high maternal consumption of fat promotes obesity and increased metabolic risk in offspring, but less is known about the effects of other potential nutrient obesogens. Widespread increase in dietary fructose consumption over the past 30 years is associated with chronic metabolic and endocrine disorders and alterations in feeding behaviour that promote obesity. In this Perspectives, we examine the evidence linking high intakes of fructose with altered metabolism and early obesity. We review the evidence suggesting that high fructose exposure during critical periods of development of the fetus, neonate and infant can act as an obesogen by affecting lifelong neuroendocrine function, appetite control, feeding behaviour, adipogenesis, fat distribution and metabolic systems. These changes ultimately favour the long-term development of obesity and associated metabolic risk. PMID:23732284

  4. Structural and Maturational Covariance in Early Childhood Brain Development.

    PubMed

    Geng, Xiujuan; Li, Gang; Lu, Zhaohua; Gao, Wei; Wang, Li; Shen, Dinggang; Zhu, Hongtu; Gilmore, John H

    2017-03-01

    Brain structural covariance networks (SCNs) composed of regions with correlated variation are altered in neuropsychiatric disease and change with age. Little is known about the development of SCNs in early childhood, a period of rapid cortical growth. We investigated the development of structural and maturational covariance networks, including default, dorsal attention, primary visual and sensorimotor networks in a longitudinal population of 118 children after birth to 2 years old and compared them with intrinsic functional connectivity networks. We found that structural covariance of all networks exhibit strong correlations mostly limited to their seed regions. By Age 2, default and dorsal attention structural networks are much less distributed compared with their functional maps. The maturational covariance maps, however, revealed significant couplings in rates of change between distributed regions, which partially recapitulate their functional networks. The structural and maturational covariance of the primary visual and sensorimotor networks shows similar patterns to the corresponding functional networks. Results indicate that functional networks are in place prior to structural networks, that correlated structural patterns in adult may arise in part from coordinated cortical maturation, and that regional co-activation in functional networks may guide and refine the maturation of SCNs over childhood development. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  5. The SCL gene specifies haemangioblast development from early mesoderm.

    PubMed

    Gering, M; Rodaway, A R; Göttgens, B; Patient, R K; Green, A R

    1998-07-15

    The SCL gene encodes a basic helix-loop-helix (bHLH) transcription factor that is essential for the development of all haematopoietic lineages. SCL is also expressed in endothelial cells, but its function is not essential for specification of endothelial progenitors and the role of SCL in endothelial development is obscure. We isolated the zebrafish SCL homologue and show that it was co-expressed in early mesoderm with markers of haematopoietic, endothelial and pronephric progenitors. Ectopic expression of SCL mRNA in zebrafish embryos resulted in overproduction of common haematopoietic and endothelial precursors, perturbation of vasculogenesis and concomitant loss of pronephric duct and somitic tissue. Notochord and neural tube formation were unaffected. These results provide the first evidence that SCL specifies formation of haemangioblasts, the proposed common precursor of blood and endothelial lineages. Our data also underline the striking similarities between the role of SCL in haematopoiesis/vasculogenesis and the function of other bHLH proteins in muscle and neural development.

  6. Development of Water Resources Drought Early Warning System

    NASA Astrophysics Data System (ADS)

    Chen, B. P. T.; Chen, C. H.

    2017-12-01

    Signs of impending drought are often vague and result from hydrologic uncertainty. Because of this, determining the appropriate time to enforce water supply restrictions is difficult. This study proposes a drought early warning index (DEWI) that can help water resource managers to anticipate droughts so that preparations can be made to mitigate the impact of water shortages. This study employs the expected-deficit-rate of normal water supply conditions as the drought early warning index. An annual-use-reservoir-based water supply system in southern Taiwan was selected as the case study. The water supply simulation was based on reservoir storage at the evaluation time and the reservoir inflow series to cope with the actual water supply process until the end of the hydrologic year. A variety of deficits could be realized during different hydrologic years of records and assumptions of initial reservoir storage. These deficits are illustrated using the Average Shortage Rate (ASR) and the value of the ASR, namely the DEWI. The ASR is divided into 5 levels according to 5 deficit-tolerance combinations of each kind of annual demand. A linear regression model and a Neuro-Fuzzy Computing Technique model were employed to estimate the DEWI using selected factors deduced from supply-demand traits and available information, including: rainfall, reservoir inflow and storage data. The chosen methods mentioned above are used to explain a significant index is useful for both model development and decision making. Tests in the Tsengwen-Wushantou reservoir system showed this DEWI to perform very well in adopting the proper mitigation policy at the end of the wet season.

  7. Early aspirin use and the development of cardiac allograft vasculopathy.

    PubMed

    Kim, Miae; Bergmark, Brian A; Zelniker, Thomas A; Mehra, Mandeep R; Stewart, Garrick C; Page, Deborah S; Woodcome, Erica L; Smallwood, Jennifer A; Gabardi, Steven; Givertz, Michael M

    2017-12-01

    Cardiac allograft vasculopathy (CAV) remains a leading cause of morbidity and mortality after orthotopic heart transplantation (OHT). Little is known about the influence of aspirin on clinical expression of CAV. We followed 120 patients with OHT at a single center for a median of 7 years and categorized them by the presence or absence of early aspirin therapy post-transplant (aspirin treatment ≥6 months in the first year). The association between aspirin use and time to the primary end-point of angiographic moderate or severe CAV (International Society for Heart and Lung Transplantation grade ≥2) was investigated. Propensity scores for aspirin treatment were estimated using boosting models and applied by inverse probability of treatment weighting (IPTW). Despite a preponderance of risk factors for CAV among patients receiving aspirin (male sex, ischemic heart disease as the etiology of heart failure, and smoking), aspirin therapy was associated with a lower rate of moderate or severe CAV at 5 years. Event-free survival was 95.9% for patients exposed to aspirin compared with 79.6% for patients without aspirin exposure (log-rank p = 0.005). IPTW-weighted Cox regression revealed a powerful inverse association between aspirin use and moderate to severe CAV (adjusted hazard ratio 0.13; 95% confidence interval 0.03-0.59), which was directionally consistent for CAV of any severity (adjusted hazard ratio 0.50; 95% confidence interval 0.23-1.08). This propensity score-based comparative observational analysis suggests that early aspirin exposure may be associated with a reduced risk of development of moderate to severe CAV. These findings warrant prospective validation in controlled investigations. Copyright © 2017 International Society for the Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  8. Impact of Early Postnatal Androgen Exposure on Voice Development

    PubMed Central

    Grisa, Leila; Leonel, Maria L.; Gonçalves, Maria I. R.; Pletsch, Francisco; Sade, Elis R.; Custódio, Gislaine; Zagonel, Ivete P. S.; Longui, Carlos A.; Figueiredo, Bonald C.

    2012-01-01

    Background The impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT) in childhood. Methods The long-term effects of androgen exposure on the fundamental vocal frequency (F0), vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years) and 10 adolescent (13.6 to 17.8 years) female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels. Results Of the 19 subjects, 17 (89%) had been diagnosed with ACT before 4 years of age, 1 (5%) at 8.16 years, and 1 (5%) at 10.75 years. Androgen exposure (2 to 30 months) was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19) of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz) and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz. Conclusions Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors. PMID:23284635

  9. Developing an Early Warning System for Machu Picchu Pueblo, Peru.

    NASA Astrophysics Data System (ADS)

    Bulmer, Mark; Farquhar, Tony

    2010-05-01

    The town of Machu Picchu, Peru, is linked to Ollantaytambo and Cusco by rail and serves as the main station for the 400,000+ tourists visiting Machu Picchu. Due to the tourist industry the town grown threefold in population in the past two decades. Today, due to the limited availability of low-lying ground, construction is occurring higher up on the unstable valley slopes. The town is located at 2000 m asl while the surrounding peaks rise to over 4000 m asl. Slopes range from < 10° on the valley floor to > 70° in the surrounding granite mountains. The town has grown on the downstream right bank of the Vilcanota River, at the confluence of the Alcamayo and the Aguas Calientes Rivers. Broadly, a dry winter season runs from May to August with a rainy summer season running from October to March. The rainy months provide around 80% of the annual rainfall average, which ranges from 1,600 to 2,300 mm. Seasonal temperature variations are considered modest. An assessment of the geohazards in and around the town has been undertaken. Those of particular concern to the town are 1) large rocks falling onto the town and/or the rail line, 2) flash flooding by any one of its three rivers, and 3) mudflows and landslides. To improve the existing municipal warning system a prototype early warning system incorporating suitable technologies that could monitor weather, river flow and slope satability was installed along the Aguas Calientes River in 2009. This has a distributed modular construction allowing most components to be installed, maintained, swapped, salvaged, repaired and/or replaced by local technicians. A diverse set of candidate power, communication and sensor technologies was deployed and evaluated. Most of the candidate technologies had never been deployed in similar terrain, altitude or weather. The successful deployment of the prototype proved that it is technically feasible to develop early warning capacity in the town.

  10. Socioeconomic disadvantage and neural development from infancy through early childhood

    PubMed Central

    Chin-Lun Hung, Galen; Hahn, Jill; Alamiri, Bibi; Buka, Stephen L; Goldstein, Jill M; Laird, Nan; Nelson, Charles A; Smoller, Jordan W; Gilman, Stephen E

    2015-01-01

    Background: Early social experiences are believed to shape neurodevelopment, with potentially lifelong consequences. Yet minimal evidence exists regarding the role of the social environment on children’s neural functioning, a core domain of neurodevelopment. Methods: We analysed data from 36 443 participants in the United States Collaborative Perinatal Project, a socioeconomically diverse pregnancy cohort conducted between 1959 and 1974. Study outcomes included: physician (neurologist or paediatrician)-rated neurological abnormality neonatally and thereafter at 4 months and 1 and 7 years; indicators of neurological hard signs and soft signs; and indicators of autonomic nervous system function. Results: Children born to socioeconomically disadvantaged parents were more likely to exhibit neurological abnormalities at 4 months [odds ratio (OR) = 1.20; 95% confidence interval (CI) = 1.06, 1.37], 1 year (OR = 1.35; CI = 1.17, 1.56), and 7 years (OR = 1.67; CI = 1.48, 1.89), and more likely to exhibit neurological hard signs (OR = 1.39; CI = 1.10, 1.76), soft signs (OR = 1.26; CI = 1.09, 1.45) and autonomic nervous system dysfunctions at 7 years. Pregnancy and delivery complications, themselves associated with socioeconomic disadvantage, did not account for the higher risks of neurological abnormalities among disadvantaged children. Conclusions: Parental socioeconomic disadvantage was, independently from pregnancy and delivery complications, associated with abnormal child neural development during the first 7 years of life. These findings reinforce the importance of the early environment for neurodevelopment generally, and expand knowledge regarding the domains of neurodevelopment affected by environmental conditions. Further work is needed to determine the mechanisms linking socioeconomic disadvantage with children’s neural functioning, the timing of such mechanisms and their potential reversibility. PMID:26675752

  11. Developing Adaptive Systems at Early Stages of Children's Foreign Language Development

    ERIC Educational Resources Information Center

    Espada, Ana Belen Cumbreno; Garcia, Mercedes Rico; Fuentes, Alejandro Curado; Gomez, Eva Ma Dominguez

    2006-01-01

    This paper describes the integration of hypermedia adaptive systems for foreign language learners at an early age. Our research project is concerned with exploring the relationship between language learning and information technology according to six different phases: a preliminary study of the plausible adaptive system; the development of lessons…

  12. Preschoolers Know, but How Do They Know? Developing a Framework for Early Epistemology Development

    ERIC Educational Resources Information Center

    Winsor, Denise L.; Blake, Sally

    2009-01-01

    Two areas that are lacking for the purpose of training high-quality preschool teachers; and constructing developmentally appropriate learning standards and curriculum for preschool children are awareness of early epistemic development (beliefs about knowledge and knowing) and understanding preschoolers' cognitive processes during epistemic…

  13. Origins and early development of human body knowledge.

    PubMed

    Slaughter, Virginia; Heron, Michelle

    2004-01-01

    As a knowable object, the human body is highly complex. Evidence from several converging lines of research, including psychological studies, neuroimaging and clinical neuropsychology, indicates that human body knowledge is widely distributed in the adult brain, and is instantiated in at least three partially independent levels of representation. Sensorimotor body knowledge is responsible for on-line control and movement of one's own body and may also contribute to the perception of others' moving bodies; visuo-spatial body knowledge specifies detailed structural descriptions of the spatial attributes of the human body; and lexical-semantic body knowledge contains language-based knowledge about the human body. In the first chapter of this Monograph, we outline the evidence for these three hypothesized levels of human body knowledge, then review relevant literature on infants' and young children's human body knowledge in terms of the three-level framework. In Chapters II and III, we report two complimentary series of studies that specifically investigate the emergence of visuo-spatial body knowledge in infancy. Our technique is to compare infants'responses to typical and scrambled human bodies, in order to evaluate when and how infants acquire knowledge about the canonical spatial layout of the human body. Data from a series of visual habituation studies indicate that infants first discriminate scrambled from typical human body picture sat 15 to 18 months of age. Data from object examination studies similarly indicate that infants are sensitive to violations of three-dimensional human body stimuli starting at 15-18 months of age. The overall pattern of data supports several conclusions about the early development of human body knowledge: (a) detailed visuo-spatial knowledge about the human body is first evident in the second year of life, (b) visuo-spatial knowledge of human faces and human bodies are at least partially independent in infancy and (c) infants' initial

  14. Infant feeding effects on early neurocognitive development in Asian children.

    PubMed

    Cai, Shirong; Pang, Wei Wei; Low, Yen Ling; Sim, Lit Wee; Sam, Suet Chian; Bruntraeger, Michaela Bianka; Wong, Eric Qinlong; Fok, Doris; Broekman, Birit F P; Singh, Leher; Richmond, Jenny; Agarwal, Pratibha; Qiu, Anqi; Saw, Seang Mei; Yap, Fabian; Godfrey, Keith M; Gluckman, Peter D; Chong, Yap-Seng; Meaney, Michael J; Kramer, Michael S; Rifkin-Graboi, Anne

    2015-02-01

    Breastfeeding has been shown to enhance global measures of intelligence in children. However, few studies have examined associations between breastfeeding and specific cognitive task performance in the first 2 y of life, particularly in an Asian population. We assessed associations between early infant feeding and detailed measures of cognitive development in the first 2 y of life in healthy Asian children born at term. In a prospective cohort study, neurocognitive testing was performed in 408 healthy children (aged 6, 18, and 24 mo) from uncomplicated pregnancies (i.e., birth weight >2500 and <4000 g, gestational age ≥37 wk, and 5-min Apgar score ≥9). Tests included memory (deferred imitation, relational binding, habituation) and attention tasks (visual expectation, auditory oddball) as well as the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III). Children were stratified into 3 groups (low, intermediate, and high) on the basis of breastfeeding duration and exclusivity. After potential confounding variables were controlled for, significant associations and dose-response relations were observed for 4 of the 15 tests. Higher breastfeeding exposure was associated with better memory at 6 mo, demonstrated by greater preferential looking toward correctly matched items during early portions of a relational memory task (i.e., relational binding task: P-trend = 0.015 and 0.050 for the first two 1000-ms time bins, respectively). No effects of breastfeeding were observed at 18 mo. At 24 mo, breastfed children were more likely to display sequential memory during a deferred imitation memory task (P-trend = 0.048), and toddlers with more exposure to breastfeeding scored higher in receptive language [+0.93 (0.23, 1.63) and +1.08 (0.10, 2.07) for intermediate- and high-breastfeeding groups, respectively, compared with the low-breastfeeding group], as well as expressive language [+0.58 (-0.06, 1.23) and +1.22 (0.32, 2.12) for intermediate- and high

  15. Controls on development and diversity of Early Archean stromatolites

    PubMed Central

    Allwood, Abigail C.; Grotzinger, John P.; Knoll, Andrew H.; Burch, Ian W.; Anderson, Mark S.; Coleman, Max L.; Kanik, Isik

    2009-01-01

    The ≈3,450-million-year-old Strelley Pool Formation in Western Australia contains a reef-like assembly of laminated sedimentary accretion structures (stromatolites) that have macroscale characteristics suggestive of biological influence. However, direct microscale evidence of biology—namely, organic microbial remains or biosedimentary fabrics—has to date eluded discovery in the extensively-recrystallized rocks. Recently-identified outcrops with relatively good textural preservation record microscale evidence of primary sedimentary processes, including some that indicate probable microbial mat formation. Furthermore, we find relict fabrics and organic layers that covary with stromatolite morphology, linking morphologic diversity to changes in sedimentation, seafloor mineral precipitation, and inferred microbial mat development. Thus, the most direct and compelling signatures of life in the Strelley Pool Formation are those observed at the microscopic scale. By examining spatiotemporal changes in microscale characteristics it is possible not only to recognize the presence of probable microbial mats during stromatolite development, but also to infer aspects of the biological inputs to stromatolite morphogenesis. The persistence of an inferred biological signal through changing environmental circumstances and stromatolite types indicates that benthic microbial populations adapted to shifting environmental conditions in early oceans. PMID:19515817

  16. Dual odontogenic origins develop at the early stage of rat maxillary incisor development.

    PubMed

    Kriangkrai, Rungarun; Iseki, Sachiko; Eto, Kazuhiro; Chareonvit, Suconta

    2006-03-01

    Developmental process of rat maxillary incisor has been studied through histological analysis and investigation of tooth-related gene expression patterns at initial tooth development. The tooth-related genes studied here are fibroblast growth factor-8 (Fgf-8), pituitary homeobox gene-2 (Pitx-2), sonic hedgehog (Shh), muscle segment homeobox-1 (Msx-1), paired box-9 (Pax-9) and bone morphogenetic protein-4 (Bmp-4). The genes are expressed in oral epithelium and/or ectomesenchyme at the stage of epithelial thickening to the early bud stage of tooth development. Both the histological observation and tooth-related gene expression patterns during early stage of maxillary incisor development demonstrate that dual odontogenic origins aligned medio-laterally in the medial nasal process develop, subsequently only single functional maxillary incisor dental placode forms. The cascade of tooth-related gene expression patterns in rat maxillary incisor studied here is quite similar to those of the previous studies in mouse mandibular molar, even though the origins of oral epithelium and ectomesenchyme involved in development of maxillary incisor and mandibular molar are different. Thus, we conclude that maxillary incisor and mandibular molar share a similar signaling control of Fgf-8, Pitx-2, Shh, Msx-1, Pax-9 and Bmp-4 genes at the stage of oral epithelial thickening to the early bud stage of tooth development.

  17. Flight feather development: its early specialization during embryogenesis.

    PubMed

    Kondo, Mao; Sekine, Tomoe; Miyakoshi, Taku; Kitajima, Keiichi; Egawa, Shiro; Seki, Ryohei; Abe, Gembu; Tamura, Koji

    2018-01-01

    Flight feathers, a type of feather that is unique to extant/extinct birds and some non-avian dinosaurs, are the most evolutionally advanced type of feather. In general, feather types are formed in the second or later generation of feathers at the first and following molting, and the first molting begins at around two weeks post hatching in chicken. However, it has been stated in some previous reports that the first molting from the natal down feathers to the flight feathers is much earlier than that for other feather types, suggesting that flight feather formation starts as an embryonic event. The aim of this study was to determine the inception of flight feather morphogenesis and to identify embryological processes specific to flight feathers in contrast to those of down feathers. We found that the second generation of feather that shows a flight feather-type arrangement has already started developing by chick embryonic day 18, deep in the skin of the flight feather-forming region. This was confirmed by shh gene expression that shows barb pattern, and the expression pattern revealed that the second generation of feather development in the flight feather-forming region seems to start by embryonic day 14. The first stage at which we detected a specific morphology of the feather bud in the flight feather-forming region was embryonic day 11, when internal invagination of the feather bud starts, while the external morphology of the feather bud is radial down-type. The morphogenesis for the flight feather, the most advanced type of feather, has been drastically modified from the beginning of feather morphogenesis, suggesting that early modification of the embryonic morphogenetic process may have played a crucial role in the morphological evolution of this key innovation. Co-optation of molecular cues for axial morphogenesis in limb skeletal development may be able to modify morphogenesis of the feather bud, giving rise to flight feather-specific morphogenesis of traits.

  18. [Early Intervention and Cognitive Development: A Longitudinal Study with Psychologically Stressed Mother-Child-Dyad during Early Childhood].

    PubMed

    Zwönitzer, Annabel; Ziegenhain, Ute; Bovenschen, Ina; Pillhofer, Melanie; Spangler, Gottfried; Gerlach, Jennifer; Gabler, Sandra; Kindler, Heinz; Fegert, Jörg M; Künster, Anne Katrin

    2016-01-01

    Early intervention programs aiming at developing parents’ relationship and parenting skills and supporting young families have become increasingly established in Germany throughout the last decade. The present longitudinal study analyzed 53 children and their mothers receiving early intervention due to their psychosocially highly challenging life situations and personal circumstances. The children were examined at birth and at an age of twelve months as well as between ages two and four. The results revealed that the child’s cognitive development could be predicted by both maternal sensitivity and mother’s psychosocial stress. However, the amount, type, and intensity of early intervention did not have any effect on the child’s development. In terms of the effectiveness of early interventions the results implicate that interventions seems to be offered in an unspecific manner and does not contribute to an improvement of the child’s developmental status.

  19. Mammalian Wax Biosynthesis

    PubMed Central

    Cheng, Jeffrey B.; Russell, David W.

    2009-01-01

    Wax monoesters are synthesized by the esterification of fatty alcohols and fatty acids. A mammalian enzyme that catalyzes this reaction has not been isolated. We used expression cloning to identify cDNAs encoding a wax synthase in the mouse preputial gland. The wax synthase gene is located on the X chromosome and encodes a member of the acyltransferase family of enzymes that synthesize neutral lipids. Expression of wax synthase in cultured cells led to the formation of wax monoesters from straight chain saturated, unsaturated, and polyunsaturated fatty alcohols and acids. Polyisoprenols also were incorporated into wax monoesters by the enzyme. The wax synthase had little or no ability to synthesize cholesteryl esters, diacylglycerols, or triacylglycerols, whereas other acyltransferases, including the acyl-CoA:monoacylglycerol acyltransferase 1 and 2 enzymes and the acyl-CoA:diacylglycerol acyltransferase 1 and 2 enzymes, exhibited modest wax monoester synthesis activities. Confocal light microscopy indicated that the wax synthase was localized in membranes of the endoplasmic reticulum. Wax synthase mRNA was abundant in tissues rich in sebaceous glands such as the preputial gland and eyelid and was present at lower levels in other tissues. Coexpression of cDNAs specifying fatty acyl-CoA reductase 1 and wax synthase led to the synthesis of wax monoesters. The data suggest that wax monoester synthesis in mammals involves a two step biosynthetic pathway catalyzed by fatty acyl-CoA reductase and wax synthase enzymes. PMID:15220349

  20. Stem Cells in Mammalian Gonads.

    PubMed

    Wu, Ji; Ding, Xinbao; Wang, Jian

    Stem cells have great value in clinical application because of their ability to self-renew and their potential to differentiate into many different cell types. Mammalian gonads, including testes for males and ovaries for females, are composed of germline and somatic cells. In male mammals, spermatogonial stem cells maintain spermatogenesis which occurs continuously in adult testis. Likewise, a growing body of evidence demonstrated that female germline stem cells could be found in mammalian ovaries. Meanwhile, prior studies have shown that somatic stem cells exist in both testes and ovaries. In this chapter, we focus on mammalian gonad stem cells and discuss their characteristics as well as differentiation potentials.

  1. Mammalian Evolution May not Be Strictly Bifurcating

    PubMed Central

    Hallström, Björn M.; Janke, Axel

    2010-01-01

    The massive amount of genomic sequence data that is now available for analyzing evolutionary relationships among 31 placental mammals reduces the stochastic error in phylogenetic analyses to virtually zero. One would expect that this would make it possible to finally resolve controversial branches in the placental mammalian tree. We analyzed a 2,863,797 nucleotide-long alignment (3,364 genes) from 31 placental mammals for reconstructing their evolution. Most placental mammalian relationships were resolved, and a consensus of their evolution is emerging. However, certain branches remain difficult or virtually impossible to resolve. These branches are characterized by short divergence times in the order of 1–4 million years. Computer simulations based on parameters from the real data show that as little as about 12,500 amino acid sites could be sufficient to confidently resolve short branches as old as about 90 million years ago (Ma). Thus, the amount of sequence data should no longer be a limiting factor in resolving the relationships among placental mammals. The timing of the early radiation of placental mammals coincides with a period of climate warming some 100–80 Ma and with continental fragmentation. These global processes may have triggered the rapid diversification of placental mammals. However, the rapid radiations of certain mammalian groups complicate phylogenetic analyses, possibly due to incomplete lineage sorting and introgression. These speciation-related processes led to a mosaic genome and conflicting phylogenetic signals. Split network methods are ideal for visualizing these problematic branches and can therefore depict data conflict and possibly the true evolutionary history better than strictly bifurcating trees. Given the timing of tectonics, of placental mammalian divergences, and the fossil record, a Laurasian rather than Gondwanan origin of placental mammals seems the most parsimonious explanation. PMID:20591845

  2. Mammalian evolution may not be strictly bifurcating.

    PubMed

    Hallström, Björn M; Janke, Axel

    2010-12-01

    The massive amount of genomic sequence data that is now available for analyzing evolutionary relationships among 31 placental mammals reduces the stochastic error in phylogenetic analyses to virtually zero. One would expect that this would make it possible to finally resolve controversial branches in the placental mammalian tree. We analyzed a 2,863,797 nucleotide-long alignment (3,364 genes) from 31 placental mammals for reconstructing their evolution. Most placental mammalian relationships were resolved, and a consensus of their evolution is emerging. However, certain branches remain difficult or virtually impossible to resolve. These branches are characterized by short divergence times in the order of 1-4 million years. Computer simulations based on parameters from the real data show that as little as about 12,500 amino acid sites could be sufficient to confidently resolve short branches as old as about 90 million years ago (Ma). Thus, the amount of sequence data should no longer be a limiting factor in resolving the relationships among placental mammals. The timing of the early radiation of placental mammals coincides with a period of climate warming some 100-80 Ma and with continental fragmentation. These global processes may have triggered the rapid diversification of placental mammals. However, the rapid radiations of certain mammalian groups complicate phylogenetic analyses, possibly due to incomplete lineage sorting and introgression. These speciation-related processes led to a mosaic genome and conflicting phylogenetic signals. Split network methods are ideal for visualizing these problematic branches and can therefore depict data conflict and possibly the true evolutionary history better than strictly bifurcating trees. Given the timing of tectonics, of placental mammalian divergences, and the fossil record, a Laurasian rather than Gondwanan origin of placental mammals seems the most parsimonious explanation.

  3. Vocational Preferences of Early Adolescents: Their Development in Social Context.

    ERIC Educational Resources Information Center

    Vondracek, Fred W.; Silbereisen, Rainer K.; Reitzle, Matthias; Wiesner, Margit

    1999-01-01

    This study compared the timing of early vocational preferences in young adolescents from former East Germany and West Germany. Results suggested that as the memory of the Communist system fades and as younger adolescents have had less exposure to it, East-West differences tend to disappear. The formation of early vocational preferences was…

  4. Development of Conceptually Focused Early Numeracy Skill Indicators

    ERIC Educational Resources Information Center

    Methe, Scott A.; Begeny, John C.; Leary, Lemontrel L.

    2011-01-01

    This research was conducted to evaluate the technical properties of a set of early numeracy CBM tests that were designed to operationalize early numeric concepts. Data were collected over the course of a school year from 113 kindergarten and first-grade children using nine separate tests with three alternative forms. In addition, test-retest…

  5. Workforce Development in Early Childhood Education and Care. Research Overview

    ERIC Educational Resources Information Center

    Bretherton, Tanya

    2010-01-01

    The early childhood education and care industry in Australia is undergoing a shift in philosophy. Changes in policy are driving the industry towards a combined early childhood education and care focus, away from one on child care only. This move has implications for the skilling of the child care workforce. This research overview describes the…

  6. How Early Child Care Affects Later Development. Science Briefs

    ERIC Educational Resources Information Center

    National Scientific Council on the Developing Child, 2007

    2007-01-01

    "Science Briefs" summarize the findings and implications of a recent study in basic science or clinical research. This brief reports on the study "Are there Long-Term Effects of Early Child Care?" (J. Belsky, D. L. Vandell, M. Burchinal, K. A. Clarke-Stewart, K. McCartney, M. T. Owen, M. T., and The NICHD Early Child Care Research Network).…

  7. Nga Kaitaunaki Kohungahunga (Early Childhood Development Unit). Annual Report for July 1, 1991-June 30, 1992.

    ERIC Educational Resources Information Center

    Early Childhood Development Unit, Wellington (New Zealand).

    The Early Childhood Development Unit, a government agency located in Aotearoa, New Zealand, promotes and encourages the development and provision of quality, accessible, and culturally appropriate early childhood services. The Unit operates in six activity or output areas. First, to increase access to early childhood education, in 1991-92 the unit…

  8. The Development of Early Childhood Teachers' Language Knowledge in Different Educational Tracks

    ERIC Educational Resources Information Center

    Strohmer, Janina; Mischo, Christoph

    2015-01-01

    Early childhood teachers should have extensive knowledge about language and language development, because these facets of professional knowledge are considered as important requirements for fostering language development in early childhood education settings. It is assumed that early childhood teachers acquire this knowledge during pre-service…

  9. Feasibility of an Online Professional Development Program for Early Intervention Practitioners

    ERIC Educational Resources Information Center

    Kyzar, Kathleen B.; Chiu, Caya; Kemp, Peggy; Aldersey, Heather Michelle; Turnbull, Ann P.; Lindeman, David P.

    2014-01-01

    This article reports findings from 2 studies situated within a larger scope of design research on a professional development program, "Early Years," for Part C early intervention practitioners, working with families in home and community settings. Early Years includes online modules and onsite mentor coaching, and its development has…

  10. Applying Early Systems Engineering: Injecting Knowledge into the Capability Development Process

    DTIC Science & Technology

    2012-10-01

    involves early use of systems engi- neering and technical analyses to supplement the existing operational analysis techniques currently used in...complexity, and costs of systems now being developed require tight coupling between operational requirements stated in the CDD, system requirements...Fleischer » Keywords: Capability Development, Competitive Prototyping, Knowledge Points, Early Systems Engineering Applying Early Systems

  11. Association between sleep position and early motor development.

    PubMed

    Majnemer, Annette; Barr, Ronald G

    2006-11-01

    To compare motor performance in infants sleeping in prone versus supine positions. Healthy 4-month-olds (supine: n = 71, prone: n = 12) and 6-month olds (supine: n = 50, prone: n = 22) were evaluated with the Alberta Infant Motor Scale (AIMS) and Peabody Developmental Motor Scale (PDMS), and parents completed a positioning diary. Infants were reassessed at 15 months. At 4 months, motor scores were lower in the supine group and were less likely to achieve prone extension (P < .05). At 6 months, there were wide discrepancies on the AIMS (supine: 44.5 +/- 21.6, prone: 60.0 +/- 18.8, P = .005) and the gross motor PDMS (supine: 85.7 +/- 7.6, prone: 90.2 +/- 9.5, P = .03). Motor delays were documented in 22% of babies sleeping supine. Prone sleep-positioned infants were more likely to sit and roll. Daily exposure to awake prone positioning was predictive of motor performance in infants sleeping supine. At 15 months, sleep position continued to predict motor performance. Infants sleeping supine may exhibit early motor lags, associated with less time in prone while awake. This has implications for accurate interpretation of assessment of infants at risk and prevention of inappropriate referrals. Rate of infant motor development appears influenced by extrinsic factors such as positioning practices.

  12. The early growth and development study: a prospective adoption design.

    PubMed

    Leve, Leslie D; Neiderhiser, Jenae M; Ge, Xiaojia; Scaramella, Laura V; Conger, Rand D; Reid, John B; Shaw, Daniel S; Reiss, David

    2007-02-01

    The Early Growth and Development Study is a prospective adoption study of birth parents, adoptive parents, and adopted children (N=359 triads) that was initiated in 2003. The primary study aims are to examine how family processes mediate or moderate the expression of genetic influences in order to aid in the identification of specific family processes that could serve as malleable targets for intervention. Participants in the study are recruited through adoption agencies located throughout the United States, following the birth of a child. Assessments occur at 6-month intervals until the child reaches 3 years of age. Data collection includes the following primary constructs: infant and toddler temperament, social behavior, and health; birth and adoptive parent personality characteristics, psychopathology, competence, stress, and substance use; adoptive parenting and marital relations; and prenatal exposure to drugs and maternal stress. Preliminary analyses suggest the representativeness of the sample and minimal confounding effects of current trends in adoption practices, including openness and selective placement. Future plans are described.

  13. Interpersonal Development, Stability, and Change in Early Adulthood

    PubMed Central

    Wright, Aidan G. C.; Pincus, Aaron L.; Lenzenweger, Mark F.

    2011-01-01

    Objective This goal of this research was to explore the development of the interpersonal system mapped by the interpersonal circumplex in early adulthood (Ages 18-22). Method This study uses the Longitudinal Study of Personality Disorders sample (N = 250; 53% Female). Participants completed the Revised Interpersonal Adjective Scales (Wiggins, Trapnell, & Phillips, 1988) in their freshman, sophomore, and senior years of college. Estimates of structural, rank-order, mean, individual, and ipsative stability were calculated for the broad interpersonal dimensions of Dominance and Affiliation, and also the lower-order octant scales. Additionally, the interpersonal profile parameters of differentiation and prototypicality were calculated at each wave and explored longitudinally, and also used as predictors of interpersonal stability. Results We found excellent structural and high rank-order and ipsative stability in the interpersonal scales over this time period. Mean increases on the Affiliation axis, but not on the Dominance axis, were found to mask differential rates of change among the octant scales, along with significant individual variation in the rates of change. Interpersonal differentiation and prototypicality were related to higher stability in overall interpersonal style. Conclusions Results point to evidence of both stability and nuanced change, illuminating some of the features of the structural variables that can be derived from interpersonal circumplex profiles. PMID:22224462

  14. Early experiences in developing and managing the neuroscience gateway.

    PubMed

    Sivagnanam, Subhashini; Majumdar, Amit; Yoshimoto, Kenneth; Astakhov, Vadim; Bandrowski, Anita; Martone, MaryAnn; Carnevale, Nicholas T

    2015-02-01

    The last few decades have seen the emergence of computational neuroscience as a mature field where researchers are interested in modeling complex and large neuronal systems and require access to high performance computing machines and associated cyber infrastructure to manage computational workflow and data. The neuronal simulation tools, used in this research field, are also implemented for parallel computers and suitable for high performance computing machines. But using these tools on complex high performance computing machines remains a challenge because of issues with acquiring computer time on these machines located at national supercomputer centers, dealing with complex user interface of these machines, dealing with data management and retrieval. The Neuroscience Gateway is being developed to alleviate and/or hide these barriers to entry for computational neuroscientists. It hides or eliminates, from the point of view of the users, all the administrative and technical barriers and makes parallel neuronal simulation tools easily available and accessible on complex high performance computing machines. It handles the running of jobs and data management and retrieval. This paper shares the early experiences in bringing up this gateway and describes the software architecture it is based on, how it is implemented, and how users can use this for computational neuroscience research using high performance computing at the back end. We also look at parallel scaling of some publicly available neuronal models and analyze the recent usage data of the neuroscience gateway.

  15. The Early Growth and Development Study: A Prospective Adoption Design

    PubMed Central

    Leve, Leslie D.; Neiderhiser, Jenae M.; Ge, Xiaojia; Scaramella, Laura V.; Conger, Rand D.; Reid, John B.; Shaw, Daniel S.; Reiss, David

    2014-01-01

    The Early Growth and Development Study is a prospective adoption study of birth parents, adoptive parents, and adopted children (N = 350 triads) that was initiated in 2003. The primary study aims are to examine how family processes mediate or moderate the expression of genetic influences in order to aid in the identification of specific family processes that could serve as malleable targets for intervention. Participants in the study were recruited following the birth of the child through adoption agencies located throughout the United States. Assessments occur at 6-month intervals until child age 3 years. Data collection includes the following primary constructs: infant/toddler temperament, social behavior, and health; birth and adoptive parent personality characteristics, psychopathology, competence, stress, and substance use; adoptive parenting and marital relations; and prenatal exposure to drugs and maternal stress. Preliminary analyses suggest the representativeness of the sample and minimal confounding effects of current trends in adoption practices, including openness and selective placement. Future plans are described. PMID:17539368

  16. Early Environment and Neurobehavioral Development Predict Adult Temperament Clusters

    PubMed Central

    Congdon, Eliza; Service, Susan; Wessman, Jaana; Seppänen, Jouni K.; Schönauer, Stefan; Miettunen, Jouko; Turunen, Hannu; Koiranen, Markku; Joukamaa, Matti; Järvelin, Marjo-Riitta; Veijola, Juha; Mannila, Heikki; Paunio, Tiina; Freimer, Nelson B.

    2012-01-01

    Background Investigation of the environmental influences on human behavioral phenotypes is important for our understanding of the causation of psychiatric disorders. However, there are complexities associated with the assessment of environmental influences on behavior. Methods/Principal Findings We conducted a series of analyses using a prospective, longitudinal study of a nationally representative birth cohort from Finland (the Northern Finland 1966 Birth Cohort). Participants included a total of 3,761 male and female cohort members who were living in Finland at the age of 16 years and who had complete temperament scores. Our initial analyses (Wessman et al., in press) provide evidence in support of four stable and robust temperament clusters. Using these temperament clusters, as well as independent temperament dimensions for comparison, we conducted a data-driven analysis to assess the influence of a broad set of life course measures, assessed pre-natally, in infancy, and during adolescence, on adult temperament. Results Measures of early environment, neurobehavioral development, and adolescent behavior significantly predict adult temperament, classified by both cluster membership and temperament dimensions. Specifically, our results suggest that a relatively consistent set of life course measures are associated with adult temperament profiles, including maternal education, characteristics of the family’s location and residence, adolescent academic performance, and adolescent smoking. Conclusions Our finding that a consistent set of life course measures predict temperament clusters indicate that these clusters represent distinct developmental temperament trajectories and that information about a subset of life course measures has implications for adult health outcomes. PMID:22815688

  17. Early experiences in developing and managing the neuroscience gateway

    PubMed Central

    Sivagnanam, Subhashini; Majumdar, Amit; Yoshimoto, Kenneth; Astakhov, Vadim; Bandrowski, Anita; Martone, MaryAnn; Carnevale, Nicholas. T.

    2015-01-01

    SUMMARY The last few decades have seen the emergence of computational neuroscience as a mature field where researchers are interested in modeling complex and large neuronal systems and require access to high performance computing machines and associated cyber infrastructure to manage computational workflow and data. The neuronal simulation tools, used in this research field, are also implemented for parallel computers and suitable for high performance computing machines. But using these tools on complex high performance computing machines remains a challenge because of issues with acquiring computer time on these machines located at national supercomputer centers, dealing with complex user interface of these machines, dealing with data management and retrieval. The Neuroscience Gateway is being developed to alleviate and/or hide these barriers to entry for computational neuroscientists. It hides or eliminates, from the point of view of the users, all the administrative and technical barriers and makes parallel neuronal simulation tools easily available and accessible on complex high performance computing machines. It handles the running of jobs and data management and retrieval. This paper shares the early experiences in bringing up this gateway and describes the software architecture it is based on, how it is implemented, and how users can use this for computational neuroscience research using high performance computing at the back end. We also look at parallel scaling of some publicly available neuronal models and analyze the recent usage data of the neuroscience gateway. PMID:26523124

  18. The development of functional network organization in early childhood and early adolescence: A resting-state fNIRS study.

    PubMed

    Cai, Lin; Dong, Qi; Niu, Haijing

    2018-04-01

    Early childhood (7-8 years old) and early adolescence (11-12 years old) constitute two landmark developmental stages that comprise considerable changes in neural cognition. However, very limited information from functional neuroimaging studies exists on the functional topological configuration of the human brain during specific developmental periods. In the present study, we utilized continuous resting-state functional near-infrared spectroscopy (rs-fNIRS) imaging data to examine topological changes in network organization during development from early childhood and early adolescence to adulthood. Our results showed that the properties of small-worldness and modularity were not significantly different across development, demonstrating the developmental maturity of important functional brain organization in early childhood. Intriguingly, young children had a significantly lower global efficiency than early adolescents and adults, which revealed that the integration of the distributed networks strengthens across the developmental stages underlying cognitive development. Moreover, local efficiency of young children and adolescents was significantly lower than that of adults, while there was no difference between these two younger groups. This finding demonstrated that functional segregation remained relatively steady from early childhood to early adolescence, and the brain in these developmental periods possesses no optimal network configuration. Furthermore, we found heterogeneous developmental patterns in the regional nodal properties in various brain regions, such as linear increased nodal properties in the frontal cortex, indicating increasing cognitive capacity over development. Collectively, our results demonstrated that significant topological changes in functional network organization occurred during these two critical developmental stages, and provided a novel insight into elucidating subtle changes in brain functional networks across development. Copyright

  19. Prenatal PCBs disrupt early neuroendocrine development of the rat hypothalamus

    SciTech Connect

    Dickerson, Sarah M.; Cunningham, Stephanie L.; Gore, Andrea C., E-mail: andrea.gore@mail.utexas.edu

    disrupted sexual differentiation of the POA by prenatal EDC exposures is already evident as early as the day after birth, effects that may change the trajectory of postnatal development and compromise adult reproductive function.« less

  20. Socioeconomic disadvantage and neural development from infancy through early childhood.

    PubMed

    Chin-Lun Hung, Galen; Hahn, Jill; Alamiri, Bibi; Buka, Stephen L; Goldstein, Jill M; Laird, Nan; Nelson, Charles A; Smoller, Jordan W; Gilman, Stephen E

    2015-12-01

    Early social experiences are believed to shape neurodevelopment, with potentially lifelong consequences. Yet minimal evidence exists regarding the role of the social environment on children's neural functioning, a core domain of neurodevelopment. We analysed data from 36 443 participants in the United States Collaborative Perinatal Project, a socioeconomically diverse pregnancy cohort conducted between 1959 and 1974. Study outcomes included: physician (neurologist or paediatrician)-rated neurological abnormality neonatally and thereafter at 4 months and 1 and 7 years; indicators of neurological hard signs and soft signs; and indicators of autonomic nervous system function. Children born to socioeconomically disadvantaged parents were more likely to exhibit neurological abnormalities at 4 months [odds ratio (OR) = 1.20; 95% confidence interval (CI) = 1.06, 1.37], 1 year (OR = 1.35; CI = 1.17, 1.56), and 7 years (OR = 1.67; CI = 1.48, 1.89), and more likely to exhibit neurological hard signs (OR = 1.39; CI = 1.10, 1.76), soft signs (OR = 1.26; CI = 1.09, 1.45) and autonomic nervous system dysfunctions at 7 years. Pregnancy and delivery complications, themselves associated with socioeconomic disadvantage, did not account for the higher risks of neurological abnormalities among disadvantaged children. Parental socioeconomic disadvantage was, independently from pregnancy and delivery complications, associated with abnormal child neural development during the first 7 years of life. These findings reinforce the importance of the early environment for neurodevelopment generally, and expand knowledge regarding the domains of neurodevelopment affected by environmental conditions. Further work is needed to determine the mechanisms linking socioeconomic disadvantage with children's neural functioning, the timing of such mechanisms and their potential reversibility. Published by Oxford University Press on behalf of the International

  1. Highly specialized mammalian skulls from the Late Cretaceous of South America.

    PubMed

    Rougier, Guillermo W; Apesteguía, Sebastián; Gaetano, Leandro C

    2011-11-02

    Dryolestoids are an extinct mammalian group belonging to the lineage leading to modern marsupials and placentals. Dryolestoids are known by teeth and jaws from the Jurassic period of North America and Europe, but they thrived in South America up to the end of the Mesozoic era and survived to the beginnings of the Cenozoic. Isolated teeth and jaws from the latest Cretaceous of South America provide mounting evidence that, at least in western Gondwana, dryolestoids developed into strongly endemic groups by the Late Cretaceous. However, the lack of pre-Late Cretaceous dryolestoid remains made study of their origin and early diversification intractable. Here we describe the first mammalian remains from the early Late Cretaceous of South America, including two partial skulls and jaws of a derived dryolestoid showing dental and cranial features unknown among any other group of Mesozoic mammals, such as single-rooted molars preceded by double-rooted premolars, combined with a very long muzzle, exceedingly long canines and evidence of highly specialized masticatory musculature. On one hand, the new mammal shares derived features of dryolestoids with forms from the Jurassic of Laurasia, whereas on the other hand, it is very specialized and highlights the endemic, diverse dryolestoid fauna from the Cretaceous of South America. Our specimens include only the second mammalian skull known for the Cretaceous of Gondwana, bridging a previous 60-million-year gap in the fossil record, and document the whole cranial morphology of a dryolestoid, revealing an unsuspected morphological and ecological diversity for non-tribosphenic mammals.

  2. Association of Polar Early Career Scientists: a model for experiential learning in professional development for students and early career researchers

    NASA Astrophysics Data System (ADS)

    Bradley, A. C.; Hindshaw, R. S.; Fugmann, G.; Mariash, H.

    2016-12-01

    The Association of Polar Early Career Scientists was established by early career researchers during the 2007-2008 International Polar Year as an organization for early career researchers in the polar and cryospheric sciences. APECS works to promote early career researchers through soft-skills training in both research and outreach activities, through advocating for including early career researchers in all levels of the scientific process and scientific management, and through supporting a world-wide network of researchers in varied fields. APECS is lead by early career researchers; this self-driven model has proved to be an effective means for developing the leadership, management, and communication skills that are essential in the sciences, and has shown to be sustainable even in a community where frequent turn-over is inherent to the members. Since its inception, APECS has reached over 5,500 members in more than 80 countries, and we have placed more than 50 early career researchers on working groups and steering committees with organizations around the world in the last two years alone. The close partnerships that APECS has with national and international organizations exposes members to both academic and alternative career paths, including those at the science-policy interface. This paper describes APECS's approach to experiential learning in professional development and the best practices identified over our nearly ten years as an organization.

  3. Maturation of the mammalian secretome

    PubMed Central

    Simpson, Jeremy C; Mateos, Alvaro; Pepperkok, Rainer

    2007-01-01

    A recent use of quantitative proteomics to determine the constituents of the endoplasmic reticulum and Golgi complex is discussed in the light of other available methodologies for cataloging the proteins associated with the mammalian secretory pathway. PMID:17472737

  4. Autophagy-inducing peptides from mammalian VSV and fish VHSV rhabdoviral G glycoproteins (G) as models for the development of new therapeutic molecules

    PubMed Central

    García-Valtanen, Pablo; Ortega-Villaizán, María del Mar; Martínez-López, Alicia; Medina-Gali, Regla; Pérez, Luis; Mackenzie, Simon; Figueras, Antonio; Coll, Julio M; Estepa, Amparo

    2014-01-01

    It has not been elucidated whether or not autophagy is induced by rhabdoviral G glycoproteins (G) in vertebrate organisms for which rhabdovirus infection is lethal. Our work provides the first evidence that both mammalian (vesicular stomatitis virus, VSV) and fish (viral hemorrhagic septicemia virus, VHSV, and spring viremia carp virus, SVCV) rhabdoviral Gs induce an autophagic antiviral program in vertebrate cell lines. The transcriptomic profiles obtained from zebrafish genetically immunized with either Gsvcv or Gvhsv suggest that autophagy is induced shortly after immunization and therefore, it may be an important component of the strong antiviral immune responses elicited by these viral proteins. Pepscan mapping of autophagy-inducing linear determinants of Gvhsv and Gvsv showed that peptides located in their fusion domains induce autophagy. Altogether these results suggest that strategies aimed at modulating autophagy could be used for the prevention and treatment of rhabdoviral infections such as rabies, which causes thousands of human deaths every year. PMID:25046110

  5. DAX1/NR0B1 was expressed during mammalian gonadal development and gametogenesis before it was recruited to the eutherian X chromosome.

    PubMed

    Stickels, Robert; Clark, Kevin; Heider, Thomas N; Mattiske, Deidre M; Renfree, Marilyn B; Pask, Andrew J

    2015-01-01

    The nuclear receptor subfamily 0, group B, member 1 (NR0B1) gene is an orphan nuclear receptor that is X-linked in eutherian mammals and plays a critical role in the establishment and function of the hypothalamic-pituitary-adrenal-gonadal axis. Duplication or overexpression of NR0B1 in eutherian males causes male to female sex reversal, and mutation and deletions of NR0B1 cause testicular defects. Thus, gene dosage is critical for the function of NR0B1 in normal gonadogenesis. However, NR0B1 is autosomal in all noneutherian vertebrates, including marsupials and monotreme mammals, and two active copies of the gene are compatible with both male and female gonadal development. In the current study, we examined the evolution and expression of autosomal NR0B1 during gonadal development in a marsupial (the tammar wallaby) as compared to the role of its X-linked orthologues in a eutherian (the mouse). We show that NR0B1 underwent rapid evolutionary change when it relocated from its autosomal position in the nonmammalian vertebrates, monotremes, and marsupials to an X-linked location in eutherian mammals. Despite the acquisition of a novel genomic location and a unique N-terminal domain, NR0B1 protein distribution was remarkably similar between mice and marsupials both throughout gonadal development and during gamete formation. A conserved accumulation of NR0B1 protein was observed in developing oocytes, where its function appears to be critical in the early embryo, prior to zygotic genome activation. Together these findings suggest that NR0B1 had a conserved role in gonadogenesis that existed long before it moved to the X chromosome and despite undergoing significant evolutionary change. © 2015 by the Society for the Study of Reproduction, Inc.

  6. Putrescine biosynthesis in mammalian tissues.

    PubMed Central

    Coleman, Catherine S; Hu, Guirong; Pegg, Anthony E

    2004-01-01

    L-ornithine decarboxylase provides de novo putrescine biosynthesis in mammals. Alternative pathways to generate putrescine that involve ADC (L-arginine decarboxylase) occur in non-mammalian organisms. It has been suggested that an ADC-mediated pathway may generate putrescine via agmatine in mammalian tissues. Published evidence for a mammalian ADC is based on (i) assays using mitochondrial extracts showing production of 14CO2 from [1-14C]arginine and (ii) cloned cDNA sequences that have been claimed to represent ADC. We have reinvestigated this evidence and were unable to find any evidence supporting a mammalian ADC. Mitochondrial extracts prepared from freshly isolated rodent liver and kidney using a metrizamide/Percoll density gradient were assayed for ADC activity using L-[U-14C]-arginine in the presence or absence of arginine metabolic pathway inhibitors. Although 14CO2 was produced in substantial amounts, no labelled agmatine or putrescine was detected. [14C]Agmatine added to liver extracts was not degraded significantly indicating that any agmatine derived from a putative ADC activity was not lost due to further metabolism. Extensive searches of current genome databases using non-mammalian ADC sequences did not identify a viable candidate ADC gene. One of the putative mammalian ADC sequences appears to be derived from bacteria and the other lacks several residues that are essential for decarboxylase activity. These results indicate that 14CO2 release from [1-14C]arginine is not adequate evidence for a mammalian ADC. Although agmatine is a known constituent of mammalian cells, it can be transported from the diet. Therefore L-ornithine decarboxylase remains the only established route for de novo putrescine biosynthesis in mammals. PMID:14763899

  7. Early development of Moniliophthora perniciosa basidiomata and developmentally regulated genes

    PubMed Central

    2009-01-01

    second in basidiomata, confirming their distinctiveness. The number of transcripts of the gene for plerototolysin B increased in reddish-pink mycelium and indicated an activation of the initial basidiomata production even at this culturing stage. Expression of the glucose transporter gene increased in mycelium after the stress, coinciding with a decrease of adenylate cyclase gene transcription. This indicated that nutrient uptake can be an important signal to trigger fruiting in this fungus. Conclusion The identification of genes with increased expression in this phase of the life cycle of M. perniciosa opens up new possibilities of controlling fungus spread as well as of genetic studies of biological processes that lead to basidiomycete fruiting. This is the first comparative morphologic study of the early development both in vivo and in vitro of M. perniciosa basidiomata and the first description of genes expressed at this stage of the fungal life cycle. PMID:19653910

  8. Development of an early-stage toll revenue estimation model.

    DOT National Transportation Integrated Search

    2012-05-01

    With agencies and states increasingly considering tolls as a means to finance transportation infrastructure, : there is an increasing need to quickly assess the feasibility of potential tolling projects. In the early stages : of a project when an age...

  9. Mammalian cell cultivation in space

    NASA Astrophysics Data System (ADS)

    Gmünder, Felix K.; Suter, Robert N.; Kiess, M.; Urfer, R.; Nordau, C.-G.; Cogoli, A.

    Equipment used in space for the cultivation of mammalian cells does not meet the usual standard of earth bound bioreactors. Thus, the development of a space worthy bioreactor is mandatory for two reasons: First, to investigate the effect on single cells of the space environment in general and microgravity conditions in particular, and second, to provide researchers on long term missions and the Space Station with cell material. However, expertise for this venture is not at hand. A small and simple device for animal cell culture experiments aboard Spacelab (Dynamic Cell Culture System; DCCS) was developed. It provides 2 cell culture chambers, one is operated as a batch system, the other one as a perfusion system. The cell chambers have a volume of 200 μl. Medium exchange is achieved with an automatic osmotic pump. The system is neither mechanically stirred nor equipped with sensors. Oxygen for cell growth is provided by a gas chamber that is adjacent to the cell chambers. The oxygen gradient produced by the growing cells serves to maintain the oxygen influx by diffusion. Hamster kidney cells growing on microcarriers were used to test the biological performance of the DCCS. On ground tests suggest that this system is feasible.

  10. Early physical and motor development of mouse offspring exposed to valproic acid throughout intrauterine development.

    PubMed

    Podgorac, Jelena; Pešić, Vesna; Pavković, Željko; Martać, Ljiljana; Kanazir, Selma; Filipović, Ljupka; Sekulić, Slobodan

    2016-09-15

    Clinical research has identified developmental delay and physical malformations in children prenatally exposed to the antiepileptic drug (AED) valproic acid (VPA). However, the early signs of neurodevelopmental deficits, their evolution during postnatal development and growth, and the dose effects of VPA are not well understood. The present study aimed to examine the influence of maternal exposure to a wide dose range (50, 100, 200 and 400mg/kg/day) of VPA during breeding and gestation on early physical and neuromotor development in mice offspring. Body weight gain, eye opening, the surface righting reflex (SRR) and tail suspension test (TST) were examined in the offspring at postnatal days 5, 10 and 15. We observed that: (1) all tested doses of VPA reduced the body weight of the offspring and the timing of eye opening; (2) offspring exposed to VPA displayed immature forms of righting and required more time to complete the SRR; (3) latency for the first immobilization in the TST is shorter in offspring exposed to higher doses of VPA; however, mice in all groups exposed to VPA exhibited atypical changes in this parameter during the examined period of maturation; (4) irregularities in swinging and curling activities were observed in animals exposed to higher doses of VPA. This study points to delayed somatic development and postponed maturation of the motor system in all of the offspring prenatally exposed to VPA, with stronger effects observed at higher doses. The results implicate that the strategy of continuous monitoring of general health and achievements in motor milestones during the early postnatal development in prenatally VPA-exposed offspring, irrespectively of the dose applied, could help to recognize early developmental irregularities. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. ATRX has a critical and conserved role in mammalian sexual differentiation.

    PubMed

    Huyhn, Kim; Renfree, Marilyn B; Graves, Jennifer A; Pask, Andrew J

    2011-06-14

    X-linked alpha thalassemia, mental retardation syndrome in humans is a rare recessive disorder caused by mutations in the ATRX gene. The disease is characterised by severe mental retardation, mild alpha-thalassemia, microcephaly, short stature, facial, skeletal, genital and gonadal abnormalities. We examined the expression of ATRX and ATRY during early development and gonadogenesis in two distantly related mammals: the tammar wallaby (a marsupial) and the mouse (a eutherian). This is the first examination of ATRX and ATRY in the developing mammalian gonad and fetus. ATRX and ATRY were strongly expressed in the developing male and female gonad respectively, of both species. In testes, ATRY expression was detected in the Sertoli cells, germ cells and some interstitial cells. In the developing ovaries, ATRX was initially restricted to the germ cells, but was present in the granulosa cells of mature ovaries from the primary follicle stage onwards and in the corpus luteum. ATRX mRNA expression was also examined outside the gonad in both mouse and tammar wallaby whole embryos. ATRX was detected in the developing limbs, craniofacial elements, neural tissues, tail and phallus. These sites correspond with developmental deficiencies displayed by ATR-X patients. There is a complex expression pattern throughout development in both mammals, consistent with many of the observed ATR-X syndrome phenotypes in humans. The distribution of ATRX mRNA and protein in the gonads was highly conserved between the tammar and the mouse. The expression profile within the germ cells and somatic cells strikingly overlaps with that of DMRT1, suggesting a possible link between these two genes in gonadal development. Taken together, these data suggest that ATRX has a critical and conserved role in normal development of the testis and ovary in both the somatic and germ cells, and that its broad roles in early mammalian development and gonadal function have remained unchanged for over 148 million

  12. ATRX has a critical and conserved role in mammalian sexual differentiation

    PubMed Central

    2011-01-01

    Background X-linked alpha thalassemia, mental retardation syndrome in humans is a rare recessive disorder caused by mutations in the ATRX gene. The disease is characterised by severe mental retardation, mild alpha-thalassemia, microcephaly, short stature, facial, skeletal, genital and gonadal abnormalities. Results We examined the expression of ATRX and ATRY during early development and gonadogenesis in two distantly related mammals: the tammar wallaby (a marsupial) and the mouse (a eutherian). This is the first examination of ATRX and ATRY in the developing mammalian gonad and fetus. ATRX and ATRY were strongly expressed in the developing male and female gonad respectively, of both species. In testes, ATRY expression was detected in the Sertoli cells, germ cells and some interstitial cells. In the developing ovaries, ATRX was initially restricted to the germ cells, but was present in the granulosa cells of mature ovaries from the primary follicle stage onwards and in the corpus luteum. ATRX mRNA expression was also examined outside the gonad in both mouse and tammar wallaby whole embryos. ATRX was detected in the developing limbs, craniofacial elements, neural tissues, tail and phallus. These sites correspond with developmental deficiencies displayed by ATR-X patients. Conclusions There is a complex expression pattern throughout development in both mammals, consistent with many of the observed ATR-X syndrome phenotypes in humans. The distribution of ATRX mRNA and protein in the gonads was highly conserved between the tammar and the mouse. The expression profile within the germ cells and somatic cells strikingly overlaps with that of DMRT1, suggesting a possible link between these two genes in gonadal development. Taken together, these data suggest that ATRX has a critical and conserved role in normal development of the testis and ovary in both the somatic and germ cells, and that its broad roles in early mammalian development and gonadal function have remained

  13. Mammalian enamel maturation: Crystallographic changes prior to tooth eruption.

    PubMed

    Kallistová, Anna; Horáček, Ivan; Šlouf, Miroslav; Skála, Roman; Fridrichová, Michaela

    2017-01-01

    Using the distal molar of a minipig as a model, we studied changes in the microstructural characteristics of apatite crystallites during enamel maturation (16-23 months of postnatal age), and their effects upon the mechanical properties of the enamel coat. The slow rate of tooth development in a pig model enabled us to reveal essential heterochronies in particular components of the maturation process. The maturation changes began along the enamel-dentine junction (EDJ) of the trigonid, spreading subsequently to the outer layers of the enamel coat to appear at the surface zone with a 2-month delay. Correspondingly, at the distal part of the tooth the timing of maturation processes is delayed by 3-5 month compared to the mesial part of the tooth. The early stage of enamel maturation (16-20 months), when the enamel coat is composed almost exclusively of radial prismatic enamel, is characterized by a gradual increase in crystallite thickness (by a mean monthly increment of 3.8 nm); and an increase in the prism width and thickness of crystals composed of elementary crystallites. The late stage of maturation (the last two months prior to tooth eruption), marked with the rapid appearance of the interprismatic matrix (IPM) during which the crystals densely infill spaces between prisms, is characterized by an abrupt decrease in microstrain and abrupt changes in the micromechanical properties of the enamel: a rapid increase in its ability to resist long-term load and its considerable hardening. The results suggest that in terms of crystallization dynamics the processes characterizing the early and late stage of mammalian enamel maturation represent distinct entities. In regards to common features with enamel formation in the tribosphenic molar we argue that the separation of these processes could be a common apomorphy of mammalian amelogenetic dynamics in general.

  14. Mammalian enamel maturation: Crystallographic changes prior to tooth eruption

    PubMed Central

    Kallistová, Anna; Horáček, Ivan; Šlouf, Miroslav; Skála, Roman; Fridrichová, Michaela

    2017-01-01

    Using the distal molar of a minipig as a model, we studied changes in the microstructural characteristics of apatite crystallites during enamel maturation (16-23 months of postnatal age), and their effects upon the mechanical properties of the enamel coat. The slow rate of tooth development in a pig model enabled us to reveal essential heterochronies in particular components of the maturation process. The maturation changes began along the enamel-dentine junction (EDJ) of the trigonid, spreading subsequently to the outer layers of the enamel coat to appear at the surface zone with a 2-month delay. Correspondingly, at the distal part of the tooth the timing of maturation processes is delayed by 3-5 month compared to the mesial part of the tooth. The early stage of enamel maturation (16-20 months), when the enamel coat is composed almost exclusively of radial prismatic enamel, is characterized by a gradual increase in crystallite thickness (by a mean monthly increment of 3.8 nm); and an increase in the prism width and thickness of crystals composed of elementary crystallites. The late stage of maturation (the last two months prior to tooth eruption), marked with the rapid appearance of the interprismatic matrix (IPM) during which the crystals densely infill spaces between prisms, is characterized by an abrupt decrease in microstrain and abrupt changes in the micromechanical properties of the enamel: a rapid increase in its ability to resist long-term load and its considerable hardening. The results suggest that in terms of crystallization dynamics the processes characterizing the early and late stage of mammalian enamel maturation represent distinct entities. In regards to common features with enamel formation in the tribosphenic molar we argue that the separation of these processes could be a common apomorphy of mammalian amelogenetic dynamics in general. PMID:28196135

  15. [Psychohygienic problems of development in early childhood (author's transl)].

    PubMed

    Pechstein, J

    1976-01-01

    For a "social environmental protection" as one of the most urgent problems in infantile psychohygiene, the following conclusions should be taken into consideration: 1. In particular during the first years of life the development of the child is, within certain limits, sensitive to influences from the environment and therefore it can be fostered or disturbed from the outside. Congenital, prenatal, perinatal and postnatal injuries to the brain and sensory organs must be given great attention psychohygienically. 2. The social influences exercised on the child by persons of his environment, their availability, their emotional relationships and the development of a durable link predominate psychohygienically. In addition, the material security of young families and their type of accommodation (e.g. granting of loans to help set up a home) must be considered. 3. The possibilities of exercising a positive educational influence on a mentally and psychically sound development of the child as a person and member of society are greatest at the beginning of life and diminish during childhood. The effectiveness of negative educational and social interference factors is also subject to this rule from which again the necessity of adopting psychohygienic measures for the young child is derived. 4. The phenomenon of increasingly imbalanced behaviour of older children and juveniles which cause concern today, are as a rule symptoms of a chiefly environmentally determined disturbance upsetting the personality, which often originates in early childhood. Psychohygienic measures must be concentrated on this. 5. The inadequate care of young children accounting for one third of the population, a phenomenon which can be read in the statistical records and which has risen sharply during the last few years, makes it possible to forecast a further increase in developmental and behavioral disturbances of both an intellectual and psychological nature as well as in infantile and juvenile

  16. Riding the glial monorail: a common mechanism for glial-guided neuronal migration in different regions of the developing mammalian brain.

    PubMed

    Hatten, M E

    1990-05-01

    In vitro studies from our laboratory indicate that granule neurons, purified from early postnatal mouse cerebellum, migrate on astroglial fibers by forming a 'migration junction' with the glial fiber along the length of the neuronal soma and extending a motile 'leading process' in the direction of migration. Similar dynamics are seen for hippocampal neurons migrating along hippocampal astroglial fibers in vitro. In heterotypic recombinations of neurons and glia from mouse cerebellum and rat hippocampus, neurons migrate on astroglial processes with a cytology and neuron-glia relationship identical to that of homotypic neuronal migration in vitro. In all four cases, the migrating neuron presents a stereotyped posture, speed and mode of movement, suggesting that glial fibers provide a generic pathway for neuronal migration in developing brain. Studies on the molecular basis of glial-guided migration suggest that astrotactin, a neuronal antigen that functions as a neuron-glia ligand, is likely to play a crucial role in the locomotion of the neuron along glial fibers. The navigation of neurons from glial fibers into cortical layers, in turn, is likely to involve neuron-neuron adhesion ligands.

  17. Early Childhood Development in the Montreal Study Area (Quebec). Understanding the Early Years

    ERIC Educational Resources Information Center

    Human Resources Development Canada, 2003

    2003-01-01

    Understanding the Early Years (UEY) is a national research initiative. It provides communities with information to enable them to make informed decisions about the best policies and most appropriate programs for Canadian families with young children. This report is based on one of seven communities studied in 2001-2002. Children's outcomes were…

  18. Early Childhood Development in Abbotsford, British Columbia. Understanding the Early Years

    ERIC Educational Resources Information Center

    Human Resources Development Canada, 2003

    2003-01-01

    Understanding the Early Years (UEY) is a national research initiative. It provides communities with information to enable them to make informed decisions about the best policies and most appropriate programs for Canadian families with young children. This report is based on one of seven communities studied in 2001-2002. Children's outcomes were…

  19. Early Childhood Development in Niagara Falls, Ontario. Understanding the Early Years

    ERIC Educational Resources Information Center

    Wilms, Douglas J.

    2003-01-01

    Understanding the Early Years (UEY) is a national research initiative. It provides communities with information to enable them to make informed decisions about the best policies and most appropriate programs for Canadian families with young children. This report is based on one of seven communities studied in 2001-2002. Children's outcomes were…

  20. Early Childhood Development in the Dixie Bloor Community of Mississauga, Ontario. Understanding the Early Years.

    ERIC Educational Resources Information Center

    Human Resources Development Canada, 2003

    2003-01-01

    Understanding the Early Years (UEY) is a national research initiative. It provides communities with information to enable them to make informed decisions about the best policies and most appropriate programs for Canadian families with young children. This report is based on one of seven communities studied in 2001-2002. Children's outcomes were…

  1. Early Childhood Development in Hampton/Sussex, New Brunswick. Understanding the Early Years

    ERIC Educational Resources Information Center

    Willms, J. Douglas

    2003-01-01

    Understanding the Early Years (UEY) is a national research initiative. It provides communities with information to enable them to make informed decisions about the best policies and most appropriate programs for Canadian families with young children. This report is based on one of seven communities studied in 2001-2002. Children's outcomes were…

  2. The Development of Prosocial Behaviour in Early Childhood: Contributions of Early Parenting and Self-Regulation

    ERIC Educational Resources Information Center

    Williams, Kate E.; Berthelsen, Donna

    2017-01-01

    This research considers the role of parenting practices and early self-regulation, on children's prosocial behaviour when they begin school. Data for 4007 children were drawn from "Growing Up in Australia: The Longitudinal Study of Australian Children" (LSAC). The analyses explored relations between self-reported parenting practices for…

  3. Localization of DNA methyltransferase-1 during oocyte differentiation, in vitro maturation and early embryonic development in cow

    PubMed Central

    Lodde, V.; Modina, S.C.; Franciosi, F.; Zuccari, E.; Tessaro, I.; Luciano, A.M.

    2009-01-01

    DNA methyltransferase-1 (Dnmt1) is involved in the maintenance of DNA methylation patterns and is crucial for normal mammalian development. The aim of the present study was to assess the localization of Dnmt1 in cow, during the latest phases of oocyte differentiation and during the early stages of segmentation. Dnmt1 expression and localization were assessed in oocytes according to the chromatin configuration, which in turn provides an important epigenetic mechanism for the control of global gene expression and represents a morphological marker of oocyte differentiation. We found that the initial chromatin condensation was accompanied by a slight increase in the level of global DNA methylation, as assessed by 5-methyl-cytosine immunostaining followed by laser scanning confocal microscopy analysis (LSCM). RT-PCR confirmed the presence of Dnmt1 transcripts throughout this phase of oocyte differentiation. Analogously, Dnmt1 immunodetection and LSCM indicated that the protein was always present and localized in the cytoplasm, regardless the chromatin configuration and the level of global DNA methylation. Moreover, our data indicate that while Dnmt1 is retained in the cytoplasm in metaphase II stage oocytes and zygotes, it enters the nuclei of 8–16 cell stage embryos. As suggested in mouse, the functional meaning of the presence of Dnmt1 in the bovine embryo nuclei could be the maintainement of the methylation pattern of imprinted genes. In conclusion, the present work provides useful elements for the study of Dnmt1 function during the late stage of oocyte differentiation, maturation and early embryonic development in mammals. PMID:22073356

  4. Developing and Validating a Survey of Korean Early Childhood English Teachers' Knowledge

    ERIC Educational Resources Information Center

    Kim, Jung In

    2015-01-01

    The main purpose of this study is to develop and validate a valid measure of the early childhood (EC) English teacher knowledge. Through extensive literature review on second/foreign language (L2/FL) teacher knowledge, early childhood teacher knowledge and early childhood language teacher knowledge, and semi-structured interviews from current…

  5. Mammalian Synthetic Biology: Engineering Biological Systems.

    PubMed

    Black, Joshua B; Perez-Pinera, Pablo; Gersbach, Charles A

    2017-06-21

    The programming of new functions into mammalian cells has tremendous application in research and medicine. Continued improvements in the capacity to sequence and synthesize DNA have rapidly increased our understanding of mechanisms of gene function and regulation on a genome-wide scale and have expanded the set of genetic components available for programming cell biology. The invention of new research tools, including targetable DNA-binding systems such as CRISPR/Cas9 and sensor-actuator devices that can recognize and respond to diverse chemical, mechanical, and optical inputs, has enabled precise control of complex cellular behaviors at unprecedented spatial and temporal resolution. These tools have been critical for the expansion of synthetic biology techniques from prokaryotic and lower eukaryotic hosts to mammalian systems. Recent progress in the development of genome and epigenome editing tools and in the engineering of designer cells with programmable genetic circuits is expanding approaches to prevent, diagnose, and treat disease and to establish personalized theranostic strategies for next-generation medicines. This review summarizes the development of these enabling technologies and their application to transforming mammalian synthetic biology into a distinct field in research and medicine.

  6. Annual Growth of Contract Costs for Major Programs in Development and Early Production

    DTIC Science & Technology

    2016-03-21

    changes, we can identify some underlying drivers and rule out others. Development and Early Production Differences BBP-era drops are driven by dropping...Annual Growth of Contract Costs for Major Programs in Development and Early Production Dan Davis and Philip S...Growth of Contract Costs for Major Programs in Development and Early Production Dan Davis and Philip S. Antón March 21, 2016 SUMMARY Cost is

  7. Development and Evaluation of Metacognition in Early Childhood Education

    ERIC Educational Resources Information Center

    Chatzipanteli, Athanasia; Grammatikopoulos, Vasilis; Gregoriadis, Athanasios

    2014-01-01

    The aim of the present study is to provide information and suggest ways to improve and evaluate metacognition in early childhood. Metacognition is important to learning and knowledge transfer and preparing students to become lifelong learners is a main aim of schooling. The engagement of young students in metacognitive thinking is considered…

  8. Early Development of Graphical Literacy through Knowledge Building

    ERIC Educational Resources Information Center

    Gan, Yongcheng; Scardamalia, Marlene; Hong, Huang-Yao; Zhang, Jianwei

    2010-01-01

    This study examined growth in graphical literacy for students contributing to an online, multimedia, communal environment as they advanced their understanding of biology, history and optics. Their science and history studies started early in Grade 3 and continued to the end of Grade 4; students did not receive instruction in graphics production,…

  9. Discontinuities in Early Development of the Understanding of Physical Causality

    ERIC Educational Resources Information Center

    Aschersleben, Gisa; Henning, Anne; Daum, Moritz M.

    2013-01-01

    Research on early physical reasoning has shown surprising discontinuities in developmental trajectories. Infants possess some skills that seem to disappear and then re-emerge in childhood. It has been suggested that prediction skills required in search tasks might cause these discontinuities (Keen, 2003). We tested 3.5- to 5-year-olds'…

  10. Development and Use of Early Warning Systems. SLDS Spotlight

    ERIC Educational Resources Information Center

    Curtin, Jenny; Hurwitch, Bill; Olson, Tom

    2012-01-01

    An early warning system is a data-based tool that helps predict which students are on the right path towards eventual graduation or other grade-appropriate goals. Through such systems, stakeholders at the school and district levels can view data from a wide range of perspectives and gain a deeper understanding of student data. This "Statewide…

  11. Parametric Cost and Schedule Modeling for Early Technology Development

    DTIC Science & Technology

    2018-04-02

    Best Paper in the Analysis Methods Category and 2017 Best Paper Overall awards. It was also presented at the 2017 NASA Cost and Schedule Symposium... Methods over the Project Life Cycle .............................................................................................. 2 Figure 2. Average...information contribute to the lack of data, objective models, and methods that can be broadly applied in early planning stages. Scientific

  12. Early Prevention of Childhood Disability in Developing Countries.

    ERIC Educational Resources Information Center

    Simeonsson, Rune J.

    1991-01-01

    This paper presents a disability prevention framework for community-based rehabilitation services, by conceptualizing early intervention in terms of primary, secondary, and tertiary levels of prevention. The framework views prevention as the effort to reduce a disability's expression, duration, or extended impact. (Author/JDD)

  13. Sustaining Care: Cultivating Mindful Practice in Early Years Professional Development

    ERIC Educational Resources Information Center

    Taggart, Geoff

    2015-01-01

    The practitioner's own self is a resource in early childhood education and care (ECEC). It is proposed that an experiential training focusing on the "professional self" helps to raise awareness of how psychological dispositions may impair or enhance quality of provision. A key concept in such training is emotional labour, explored with…

  14. Boosting Early Development: The Mixed Effects of Kindergarten Enrollment Age

    ERIC Educational Resources Information Center

    Zhang, Jiahui; Xin, Tao

    2012-01-01

    This study aimed to investigate the effects of kindergarten enrollment age on four-year-old Chinese children's early cognition and problem behavior using multilevel models. The sample comprised of 1,391 pre-school children (the mean age is 4.58 years old) from 74 kindergartens in six different provinces. The results demonstrated curvilinear…

  15. Further Development of Measures of Early Math Performance for Preschoolers

    ERIC Educational Resources Information Center

    VanDerHeyden, Amanda M.; Broussard, Carmen; Cooley, Amanda

    2006-01-01

    The purpose of this study was to examine the progress monitoring and screening accuracy for a set of curriculum-based measures (CBM) of early mathematics skills. Measures included counting objects, selecting numbers, naming numbers, counting, and visual discrimination. Measures were designed to be administered with preschoolers in a short period…

  16. Agency in Early Childhood Learning and Development in Cameroon

    ERIC Educational Resources Information Center

    Nsamenang, A. Bame

    2008-01-01

    This article focuses on agency, as a natural disposition in children to be active and participative. Africa's parenting attitudes and education in African family traditions encourage and foster children's responsible agency in family life, cultural and economic activities, and their own developmental learning from an early, especially within the…

  17. Incremental Validity in the Clinical Assessment of Early Childhood Development

    ERIC Educational Resources Information Center

    Liu, Xin; Zhou, Xiaobin; Lackaff, Julie

    2013-01-01

    The authors demonstrate the increment of clinical validity in early childhood assessment of physical impairment (PI), developmental delay (DD), and autism (AUT) using multiple standardized developmental screening measures such as performance measures and parent and teacher rating scales. Hierarchical regression and sensitivity/specificity analyses…

  18. Do Fine Motor Skills Contribute to Early Reading Development?

    ERIC Educational Resources Information Center

    Suggate, Sebastian; Pufke, Eva; Stoeger, Heidrun

    2018-01-01

    Background: Little is known about how fine motor skills (FMS) relate to early literacy skills, especially over and above cognitive variables. Moreover, a lack of distinction between FMS, grapho-motor and writing skills may have hampered previous work. Method: In Germany, kindergartners (n = 144, aged 6;1) were recruited before beginning formal…

  19. Positive Home Environment and Behaviour Development in Early Adolescents

    ERIC Educational Resources Information Center

    Jayalekshmi, N. B.; Dharma Raja, B. William

    2011-01-01

    Early adolescence is a period of transition when the individual changes physically and psychologically from a child to an adult. This transition involves physical, cognitive and socio- emotional changes. The developmental changes that occur during this period cause varying degree of disturbance. The changes they undergo sometimes results in…

  20. Investing in Kids: Early Childhood Programs and Local Economic Development

    ERIC Educational Resources Information Center

    Bartik, Timothy J.

    2011-01-01

    Early childhood programs, if designed correctly, pay big economic dividends down the road because they increase the skills of their participants. And since many of those participants will remain in the same state or local area as adults, the local economy benefits: more persons with better skills attract business, which provides more and better…