Deficiency of autotaxin/lysophospholipase D results in head cavity formation in mouse embryos through the LPA receptor-Rho-ROCK pathway

Although the outlines of human adenovirus entry and uncoating in HeLa cells has been clarified in recent electron microscope studies, several details remain unclear or controversial. Furthermore, morphological features of early interactions of human adenovirus with non-permissive mouse cells have not been extensively documented. In the course of studies on the effects of human adenoviruses type 5 (AD-5) and type 12 on cultured preimplantation mouse embryos we have examined virus attachment, entry and uncoating. Here we present the ultrastructural findings for AD-5.AD-5 was grown in HeLa cells and purified by successive velocity gradient and equilibrium density gradient centrifugations in CsCl. After dialysis against PBS, virus was sedimented and resuspended in embryo culture medium. Embryos were placed in culture at the 2-cell stage in Brinster's medium.

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Preplate neurons in embryonic mouse cortex: Ultrastructural observations using photoconversion of the fluorescent lipophilic dye dil

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124938 ◽

1992 ◽

Vol 50 (1) ◽

pp. 906-907

Author(s):

Linda C. Hassinger ◽

James E. Crandall

Keyword(s):

Mouse Embryos ◽

Embryonic Mouse ◽

Cortical Afferents ◽

Mouse Cortex ◽

Carbocyanine Dye ◽

Increased Sensitivity

We have begun to look directly at small numbers of afferent axons to early generated neurons that form the preplate in the developing mouse cortex. The carbocyanine dye Dil (1’1, dioctadecyl-3,3,3’3’-tetramethyl-indocarbocyanine) has proved especially useful for this goal. DiI labels axons and their terminals with greater sensitivity and without some of the disadvantages of axon filling with HRP. The increased sensitivity provided by labeling embryonic axons with DiI has given us new insights into the development of cortical afferents. For instance, we reported originally that afferents from the thalamus were present below the cortex as early as embryonic day 15 (E15) based on HRP injections into mouse embryos. By using DiI placements into the thalamus in aldehyde-fixed brains, we now know that thalamic fibers reach the cortex 24 hrs earlier.

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A TEM study of the effect of oxygen on nanocavity formation and precipitation in rapid - solidified Fe-16Ni-9Cr stainless steels

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100171237 ◽

1994 ◽

Vol 52 ◽

pp. 700-701

Author(s):

S. Wisutmethangoon ◽

T. F. Kelly ◽

J.E. Flinn

Keyword(s):

Stainless Steels ◽

High Mobility ◽

Hot Extrusion ◽

Extrusion Ratio ◽

Gas Atomization ◽

Cavity Formation ◽

Nucleation Sites ◽

Heat Treated ◽

Different Types ◽

Effect Of Oxygen

Vacancies are introduced into the crystal phase during quenching of rapid solidified materials. Cavity formation occurs because of the coalescence of the vacancies into a cluster. However, because of the high mobility of vacancies at high temperature, most of them will diffuse back into the liquid phase, and some will be lost to defects such as dislocations. Oxygen is known to stabilize cavities by decreasing the surface energy through a chemisorption process. These stabilized cavities, furthermore, act as effective nucleation sites for precipitates to form during aging. Four different types of powders with different oxygen contents were prepared by gas atomization processing. The atomized powders were then consolidated by hot extrusion at 900 °C with an extrusion ratio 10,5:1. After consolidation, specimens were heat treated at 1000 °C for 1 hr followed by water quenching. Finally, the specimens were aged at 600 °C for about 800 hrs. TEM samples were prepared from the gripends of tensile specimens of both unaged and aged alloys.

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“Cavity” formation in superplastically deformed aluminium alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177921 ◽

1990 ◽

Vol 48 (4) ◽

pp. 958-959

Author(s):

A. Cziráki ◽

E. Ková-csetényi ◽

T. Torma ◽

T. Turmezey

Keyword(s):

Grain Boundaries ◽

Aluminium Alloys ◽

Superplastic Deformation ◽

Volume Fraction ◽

Superplastic Forming ◽

Polished Surface ◽

Cavity Formation ◽

Stress Concentrations ◽

Electron Microscopic ◽

Commercial Aluminium

It is known that the formation of cavities during superplastic deformation can be correlated with the development of stress concentrations at irregularities along grain boundaries such as particles, ledges and triple points. In commercial aluminium alloys Al-Fe-Si particles or other coarse constituents may play an important role in cavity formation.Cavity formation during superplastic deformation was studied by optical metallography and transmission scanning electron microscopic investigations on Al-Mg-Si and Al-Mg-Mn alloys. The structure of particles was characterized by selected area diffraction and X-ray micro analysis. The volume fraction of “voids” was determined on mechanically polished surface.It was found by electron microscopy that strongly deformed regions are formed during superplastic forming at grain boundaries and around coarse particles.According to electron diffraction measurements these areas consist of small micro crystallized regions. See Fig.l.Comparing the volume fraction and morphology of cavities found by optical microscopy a good correlation was established between that of micro crystalline regions.

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Localization of Intracisternal a Particle Antigens in Neoplastic Cells and Preimplantation Mouse Embryos

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600003044 ◽

1980 ◽

Vol 38 ◽

pp. 696-697

Author(s):

Thomas T.F. Huang ◽

Patricia G. Calarco

Keyword(s):

Endoplasmic Reticulum ◽

Normal Development ◽

Mouse Embryos ◽

Neoplastic Cells ◽

Large Numbers ◽

Preimplantation Mouse Embryos ◽

Preimplantation Mouse ◽

Intracisternal A Particle ◽

Normal Feature

The stage specific appearance of a retravirus, termed the Intracisternal A particle (IAP) is a normal feature of early preimplantation development. To date, all feral and laboratory strains of Mus musculus and even Asian species such as Mus cervicolor and Mus pahari express the particles during the 2-8 cell stages. IAP form by budding into the endoplasmic reticulum and appear singly or as groups of donut-shaped particles within the cisternae (fig. 1). IAP are also produced in large numbers in several neoplastic cells such as certain plasmacytomas and rhabdomyosarcomas. The role of IAP, either in normal development or in neoplastic behavior, is unknown.

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