Effect of various inhibitors on several enzymes and other biochemical substances in chick embryo explants

Earlier studies in our laboratory indicated the predominance of pentose cycle activity in early embryos (Jolley, Cheldelin & Newburgh, 1959; Coffey, 1963). In addition a correlation was demonstrated between enzymes generating reduced triphosphopyridine nucleotide and lipid synthesis (Bieber, Cheldelin & Newburgh, 1962; Baker & Newburgh, 1963). Since several of the biosynthetic pathways involve this compound, it is conceivable that in a rapidly growing system such as the early chick embryo enzymes generating TPNH may play a major rôle. We have chosen to use explants of chick embryos in an attempt to gain insight into the relation of changes of these enzymes with other chemical changes which may more directly relate to differentiation. These latter changes include synthesis of such macromolecules as DNA, RNA, hemoglobin, collagen and myosin. This method permits the addition of certain chemicals to the media such as substrates or inhibitors (Hayashi et al., 1959), allowing easy manipulation of the environment.

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An electrosurgical technique for the production of localized tissue ablations in the early chick embryo

Development ◽

10.1242/dev.26.1.21 ◽

1971 ◽

Vol 26 (1) ◽

pp. 21-29

Author(s):

R. K. Jordan

Keyword(s):

Chick Embryo ◽

Low Frequency ◽

Alternating Current ◽

Chick Embryos ◽

Operating Microscope ◽

Young Chick ◽

Early Chick Embryo ◽

Electrolytic Corrosion ◽

Tungsten Metal

The passage of low-frequency alternating current was found superior to other methods considered for the production of small, discrete, electrolytic ablations in young chick embryos. Active electrodes of tungsten metal less than 5 µm in diameter were prepared by controlled electrolytic corrosion. These gave reproducible, discrete foci of destruction of the required size, with currents less than 2 mA. The identification of destroyed tissue areas was immediately apparent under the operating microscope and confirmed histologically. Preliminary studies on bilateral extirpation of the ultimobranchial primordia show the absence of the ultimobranchial bodies 6 days after destruction of the primordia at 96 h of incubation.

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Misexpression of BRE gene in the developing chick neural tube affects neurulation and somitogenesis

Molecular Biology of the Cell ◽

10.1091/mbc.e14-06-1144 ◽

2015 ◽

Vol 26 (5) ◽

pp. 978-992 ◽

Cited By ~ 7

Author(s):

Guang Wang ◽

Yan Li ◽

Xiao-Yu Wang ◽

Manli Chuai ◽

John Yeuk-Hon Chan ◽

...

Keyword(s):

Chick Embryo ◽

Embryonic Development ◽

Neural Crest ◽

Embryo Development ◽

Neural Tube ◽

Neural Crest Cells ◽

Chick Embryos ◽

Early Chick Embryo

This is the first study of the role of BRE in embryonic development using early chick embryos. BRE is expressed in the developing neural tube, neural crest cells, and somites. BRE thus plays an important role in regulating neurogenesis and indirectly somitogenesis during early chick embryo development.

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The Localization of β-Glucuronidase in the Early Chick Embryo

Development ◽

10.1242/dev.6.1.52 ◽

1958 ◽

Vol 6 (1) ◽

pp. 52-56

Author(s):

F. Billett ◽

Leela Mulherkar

Keyword(s):

Drosophila Melanogaster ◽

Chick Embryo ◽

Embryonic Development ◽

Xenopus Laevis ◽

Mouse Liver ◽

Histochemical Method ◽

Toxic Compounds ◽

Early Chick Embryo ◽

Early Embryos ◽

Drosophila Embryos

In vertebrate tissues there appears to be a connexion between β-glucuronidase and the proliferation of cells. This connexion was first noticed by Levvy, Kerr, & Campbell (1948) when they were investigating the effect of toxic compounds on mouse-liver glucuronidase. The early stages of embryonic development are characterized by rapid proliferations of cells and it is, therefore, of some interest to study the localization of β-glucuronidase during these stages. Small amounts of β-glucuronidase can be detected in the early embryos of Xenopus laevis (Billett, 1956) and in those of Drosophila melanogaster (Billett & Counce, unpublished). In these embryos no marked increase in the enzyme can be associated with the proliferation of cells. The large amount of yolk in the Xenopus and Drosophila embryos was a complicating factor in the above experiments. It was not possible to localize the enzyme in these embryos with a histochemical method.

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Responses of the early chick embryo to external cAMP sources

Development ◽

10.1242/dev.53.1.353 ◽

1979 ◽

Vol 53 (1) ◽

pp. 353-365

Author(s):

Alan R. Gingle ◽

Anthony Robertson

Keyword(s):

Chick Embryo ◽

Concentration Dependence ◽

Ventral Surface ◽

Embryonic Axis ◽

Chick Embryos ◽

Early Chick Embryo ◽

Local Sources ◽

Characteristic Concentration

Early chick embryos were stimulated with local sources of cAMP. Three major effects were observed: bending of the embryonic axis, attraction of cells on the ventral surface of the embryo, and disruption of the blastodisc. Each had a characteristic concentration dependence. These results are compared with those from studies of cells disaggregated from similar embryos.

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The participation of Palestinian-Israeli politicians in public and commercial television and radio in Israel as capability

International Communication Gazette ◽

10.1177/1748048521990565 ◽

2021 ◽

pp. 174804852199056

Author(s):

Baruch Shomron ◽

Amit Schejter

Keyword(s):

Capabilities Approach ◽

Media Representations ◽

Community Members ◽

Commercial Television ◽

Radio Stations ◽

Modes Of Representation ◽

Current Affairs ◽

Different Types ◽

The Media ◽

Insight Into

This study examines how media representations of Palestinian-Israeli politicians, can help community members realize their capabilities. The study’s database is comprised of 1,207 interviews conducted with Palestinian-Israeli politicians on news and current affairs programs on the three national television channels and the two national radio stations in Israel, for 24 months (2016-2017). We identified and analyzed the differences in the modes of representation between national and local Palestinian-Israeli politicians and between Palestinian-Israeli parliament members in the Joint List and Palestinian-Israeli parliament members in Zionist parties, all through the capabilities prism. In this study, we demonstrated how different types of Palestinian-Israeli politicians may potentially affect the realization of different political functions and capabilities. Analyzing political representations in the media through the theoretical framework of the ‘capabilities approach’ contributes to a more comprehensive insight into the roles the media can play promoting people’s wellbeing and human rights, relative to traditional media theories.

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Media Coverage and Solidarity after Tragedies: The Reporting of School Shootings in Two Nations

Comparative Sociology ◽

10.1163/15691330-12341248 ◽

2012 ◽

Vol 11 (6) ◽

pp. 845-874 ◽

Cited By ~ 14

Author(s):

James Hawdon ◽

Atte Oksanen ◽

James Hawdon ◽

Atte Oksanen ◽

...

Keyword(s):

New York ◽

Media Coverage ◽

New York Times ◽

Virginia Tech ◽

School Shootings ◽

Considerable Research ◽

National Comparison ◽

The Media ◽

Insight Into ◽

Cross National

Abstract Although considerable research analyzes the media coverage of school shootings, there is a lack of cross-national comparative studies. Yet, a cross-national comparison of the media coverage of school shootings can provide insight into how this coverage can affect communities. Our research focuses on the reporting of the school shootings at Virginia Tech in the U.S. and Jokela and Kauhajoki in Finland. Using 491 articles from the New York Times and Helsingin Sanomat published within a month of each shooting we investigate how reports vary between the nations and among the tragedies. We investigate if one style of framing a tragedy, the use of a “tragic frame,” may contribute to differences in the communities’ response to the events.

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