Astral microtubules determine the final division axis of cells confined on anisotropic surface topography

AbstractIt has been well studied that the surface topography affects the growth and development of neurons. However, the precise mechanism that the surface topography leads to cellular changes remains unknown. In this study, we created an anisotropic surface using nanodiamonds and discovered this surface topography accelerates the development of primary neurons from both the central and peripheral nervous systems. Using RNA sequencing technology, a previously uncharacterized microRNA (miR6236) was found to exhibit significant and the most substantial decrease when neurons are cultured on this nanodiamond surface. Gain- and loss-of-function assays confirm that miR6236 is the predominant molecule responsible for converting the surface topography into biological responses. We further demonstrate that the depletion of miR6236 can enhance neuroregeneration on inhibitory substrate, uncovering its therapeutic potential for promoting central nervous system regeneration.

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Fractal Analysis of AFM Data Characterizing Strongly Isotropic and Anisotropic Surface Topography

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.203-204.86 ◽

2013 ◽

Vol 203-204 ◽

pp. 86-89 ◽

Cited By ~ 22

Author(s):

Miroslaw Bramowicz ◽

Slawomir Kulesza ◽

Tomasz Lipiński ◽

Pawel Szabracki ◽

Pawel Piatkowski

Keyword(s):

Atomic Force Microscopy ◽

Surface Topography ◽

Fractal Analysis ◽

Calibration Standards ◽

Force Microscopy ◽

Anisotropic Surface ◽

Atomic Force ◽

Fractal Parameters

This study discusses changes in the value of fractal parameters determined based on functions of structure S(t), generated in different directions of anisotropy of the examined surfaces. The analyzed material consisted of AFM calibration standards TGT1, PG and TGZ1 which were used as models of strongly isotropic and anisotropic surfaces. The topography of the examined surfaces was imaged by atomic force microscopy. The obtained results indicate that all surfaces can be described mathematically to identify fractal parameters in any anisotropic direction.

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Coalescence of water films on carbon-based substrates: the role of the interfacial properties and anisotropic surface topography

Physical Chemistry Chemical Physics ◽

10.1039/c4cp06081d ◽

2015 ◽

Vol 17 (17) ◽

pp. 11284-11291 ◽

Cited By ~ 7

Author(s):

Hongru Ren ◽

Xiongying Li ◽

Hui Li ◽

Leining Zhang ◽

Weikang Wu

Keyword(s):

Surface Topography ◽

Liquid Bridge ◽

Rapid Growth ◽

Early Time ◽

Interfacial Properties ◽

Anisotropic Surface ◽

Water Films ◽

Carbon Based

The typical early-time coalescence evolution of identical water films on carbon-based substrates with the rapid growth of a liquid bridge connecting two films.

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New Insight on the Friction of Natural Fibers. Effect of Sliding Angle and Anisotropic Surface Topography

Langmuir ◽

10.1021/la400468f ◽

2013 ◽

Vol 29 (19) ◽

pp. 5857-5862 ◽

Cited By ~ 8

Author(s):

Hiroyasu Mizuno ◽

Gustavo S. Luengo ◽

Mark W. Rutland

Keyword(s):

Surface Topography ◽

Natural Fibers ◽

Sliding Angle ◽

Anisotropic Surface

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The Ultrastructure of the Nuclear Events of Binary Fission in Paramecium bursaria and the Effects of Colchicine on Cell Division

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051396 ◽

1974 ◽

Vol 32 ◽

pp. 276-277

Author(s):

L. M. Lewis

Keyword(s):

Cell Division ◽

Nuclear Envelope ◽

Condensed Chromatin ◽

Binary Fission ◽

Paramecium Bursaria ◽

Nuclear Events ◽

Division Axis

The effects of colchicine on extranuclear microtubules associated with the macronucleus of Paramecium bursaria were studied to determine the possible role that these microtubules play in controlling the shape of the macronucleus. In the course of this study, the ultrastructure of the nuclear events of binary fission in control cells was also studied.During interphase in control cells, the micronucleus contains randomly distributed clumps of condensed chromatin and microtubular fragments. Throughout mitosis the nuclear envelope remains intact. During micronuclear prophase, cup-shaped microfilamentous structures appear that are filled with condensing chromatin. Microtubules are also present and are parallel to the division axis.

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The Broad Applications of the Scanning Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100062002 ◽

1969 ◽

Vol 27 ◽

pp. 20-21

Author(s):

C. T. Nightingale ◽

S. E. Summers ◽

T. P. Turnbull

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Light Microscopy ◽

Surface Topography ◽

Great Depth ◽

Resolving Power ◽

Depth Of Field ◽

Pictorial Representations ◽

Scanning Electron

The ease of operation of the scanning electron microscope has insured its wide application in medicine and industry. The micrographs are pictorial representations of surface topography obtained directly from the specimen. The need to replicate is eliminated. The great depth of field and the high resolving power provide far more information than light microscopy.

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Effects of Ion Beam Milling on Surface Topography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070862 ◽

1973 ◽

Vol 31 ◽

pp. 84-85

Author(s):

P.G. Pawar ◽

P. Duhamel ◽

G.W. Monk

Keyword(s):

Surface Topography ◽

Ion Beam ◽

Solid Material ◽

Beam Current ◽

Atomic Mass ◽

Micro Milling ◽

Ion Milling ◽

Controlled Atmospheres ◽

Milling Operations ◽

Sufficient Energy

A beam of ions of mass greater than a few atomic mass units and with sufficient energy can remove atoms from the surface of a solid material at a useful rate. A system used to achieve this purpose under controlled atmospheres is called an ion miliing machine. An ion milling apparatus presently available as IMMI-III with a IMMIAC was used in this investigation. Unless otherwise stated, all the micro milling operations were done with Ar+ at 6kv using a beam current of 100 μA for each of the two guns, with a specimen tilt of 15° from the horizontal plane.It is fairly well established that ion bombardment of the surface of homogeneous materials can produce surface topography which resembles geological erosional features.

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Low-Loss Images in a Stem/Tem Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009244x ◽

1976 ◽

Vol 34 ◽

pp. 496-497 ◽

Cited By ~ 1

Author(s):

David C. Joy ◽

Dennis M. Maher

Keyword(s):

High Resolution ◽

Surface Topography ◽

Beam Direction ◽

Low Loss ◽

Specimen Holder ◽

Glancing Angle ◽

High Resolution Images ◽

Set Up ◽

Conventional Manner ◽

Objective Type

High-resolution images of the surface topography of solid specimens can be obtained using the low-loss technique of Wells. If the specimen is placed inside a lens of the condenser/objective type, then it has been shown that the lens itself can be used to collect and filter the low-loss electrons. Since the probeforming lenses in TEM instruments fitted with scanning attachments are of this type, low-loss imaging should be possible.High-resolution, low-loss images have been obtained in a JEOL JEM 100B fitted with a scanning attachment and a thermal, fieldemission gun. No modifications were made to the instrument, but a wedge-shaped, specimen holder was made to fit the side-entry, goniometer stage. Thus the specimen is oriented initially at a glancing angle of about 30° to the beam direction. The instrument is set up in the conventional manner for STEM operation with all the lenses, including the projector, excited.

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A procedure for cross-sectioning materials for TEM analysis without ion milling

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176848 ◽

1990 ◽

Vol 48 (4) ◽

pp. 742-743

Author(s):

J.P. Benedict ◽

Ron Anderson ◽

S. J. Klepeis

Keyword(s):

Surface Topography ◽

Milling Time ◽

Specimen Preparation ◽

Ion Milling ◽

Cleaning Operation ◽

Tem Analysis ◽

Platinum Silicide ◽

Surface Alteration ◽

Polishing Damage ◽

Tools And Methods

Traditional specimen preparation procedures for non-biological samples, especially cross section preparation procedures, involves subjecting the specimen to ion milling for times ranging from minutes to tens of hours. Long ion milling time produces surface alteration, atomic number and rough-surface topography artifacts, and high temperatures. The introduction of new tools and methods in this laboratory improved our ability to mechanically thin specimens to a point where ion milling time was reduced to one to ten minutes. Very short ion milling times meant that ion milling was more of a cleaning operation than a thinning operation. The preferential thinning and the surface topography that still existed in briefly ion milled samples made the study of interfaces between materials such as platinum silicide and silicon difficult. These two problems can be eliminated by completely eliminating the ion milling step and mechanically polishing the sample to TEM transparency with the procedure outlined in this communication. Previous successful efforts leading to mechanically thinned specimens have shown that problems center on tool tilt control, removal of polishing damage, and specimen cleanliness.

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