Sound and vibration sensitivity of VIIIth nerve fibers in the grassfrog, Rana temporaria

The High Voltage Electron Microscope Laboratory at the University of Wisconsin has been in operation a little over one year. I would like to give a progress report about our experience with this new technique. The achievement of good resolution with thick specimens has been mainly exploited so far. A cold stage which will allow us to look at frozen specimens and a hydration stage are now being installed in our microscope. This will soon make it possible to study undehydrated specimens, a particularly exciting application of the high voltage microscope.Some of the problems studied at the Madison facility are: Structure of kinetoplast and flagella in trypanosomes (J. Paulin, U. of Georgia); growth cones of nerve fibers (R. Hannah, U. of Georgia Medical School); spiny dendrites in cerebellum of mouse (Scott and Guillery, Anatomy, U. of Wis.); spindle of baker's yeast (Joan Peterson, Madison) spindle of Haemanthus (A. Bajer, U. of Oregon, Eugene) chromosome structure (Hans Ris, U. of Wisconsin, Madison). Dr. Paulin and Dr. Hanna are reporting their work separately at this meeting and I shall therefore not discuss it here.

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Fine Structure of Planarian Neuroglial Cell

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090920 ◽

1976 ◽

Vol 34 ◽

pp. 188-189 ◽

Cited By ~ 1

Author(s):

Michio Morita ◽

Jay Boyd Best

Keyword(s):

Endoplasmic Reticulum ◽

Ventral Nerve Cord ◽

Osmium Tetroxide ◽

Golgi Body ◽

Nerve Fibers ◽

Neuroglial Cell ◽

Glutaraldehyde Solution ◽

Deep Indentation ◽

Cytoplasmic Processes ◽

Longitudinal Nerve

The species of the planarian Dugesia dorotocephala was used as the experimental animal to study a neuroglial cell in the ventral nerve cord. Animals were fixed with 3% buffered glutaraldehyde solution and postfixed with 1% buffered osmium tetroxide.The neuroglial cell is multipolar, expanding into three or four cytoplasmic processes with many daughter branches. Some neuroglial processes are found to extend perpendicular to the longitudinal nerve fibers, whereas others are seen to be parallel to them. The nucleus of the neuroglial cell is irregular in shape and frequently has a deep indentation. Convex portions of the nucleus seem to be related to the areas from which cytoplasmic processes are extended. Granular endoplasmic reticulum (Fig. 4), Golgi body (Fig. 2), mitochondria (Figs. 1 and 2), microtubules (Fig. 4), and many glycogen granules are observable in the electron dense neuroglial cytoplasm. Neuroglial cells are also observed to contain various sizes of phagosomes and lipids (Fig. 2).

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Interpreting HVEM of muscle-cell impulse networks

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012103x ◽

1992 ◽

Vol 50 (1) ◽

pp. 126-127

Author(s):

Paul DeCosta ◽

Kyugon Cho ◽

Stephen Shemlon ◽

Heesung Jun ◽

Stanley M. Dunn

Keyword(s):

Structural Analysis ◽

Muscle Cell ◽

Electron Micrographs ◽

Relative Size ◽

Automatic Classification ◽

Nerve Fibers ◽

Analysis Algorithm ◽

Structural Networks

Introduction: The analysis and interpretation of electron micrographs of cells and tissues, often requires the accurate extraction of structural networks, which either provide immediate 2D or 3D information, or from which the desired information can be inferred. The images of these structures contain lines and/or curves whose orientation, lengths, and intersections characterize the overall network.Some examples exist of studies that have been done in the analysis of networks of natural structures. In, Sebok and Roemer determine the complexity of nerve structures in an EM formed slide. Here the number of nodes that exist in the image describes how dense nerve fibers are in a particular region of the skin. Hildith proposes a network structural analysis algorithm for the automatic classification of chromosome spreads (type, relative size and orientation).

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The innervation of toad lymph hearts: An ultrastructural study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124896 ◽

1992 ◽

Vol 50 (1) ◽

pp. 898-899

Author(s):

A.M. Pucci ◽

C. Fruschelli ◽

A. Rebuffat ◽

M. Guarna ◽

C. Alessandrini ◽

...

Keyword(s):

Ultrastructural Study ◽

Neuromuscular Junctions ◽

Nerve Fibers ◽

Lack Of Information ◽

Lymph Heart ◽

Muscular Pump ◽

Structure And Ultrastructure ◽

Heart Wall

Amphibians have paired muscular pump organs, called “lymph heart”, which rhythmically pump back the lymph from the large subcutaneous lymph sacs into the veins. The structure and ultrastructure of these organs is well known but to date there is a lack of information about the innervation of lymph hearts. Therefore has been carried out an ultrastructural study in order to study the distribution of the nerve fibers, and the morphology of the neuromuscular junctions in the lymph heart wall.

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Innervation of endoneurial microvessels in human sural nerve

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125002 ◽

1992 ◽

Vol 50 (1) ◽

pp. 920-921

Author(s):

John L. Beggs ◽

Peter C. Johnson ◽

Astrid G. Olafsen ◽

C. Jane Watkins

Keyword(s):

Blood Flow ◽

Blood Vessels ◽

Blood Supply ◽

Peripheral Nerves ◽

Sural Nerve ◽

Nerve Fibers ◽

Arterial Supply ◽

Autonomic Nerve ◽

Vasa Nervorum ◽

Endoneurial Blood Flow

The blood supply (vasa nervorum) to peripheral nerves is composed of an interconnected dual circulation. The endoneurium of nerve fascicles is maintained by the intrinsic circulation which is composed of microvessels primarily of capillary caliber. Transperineurial arterioles link the intrinsic circulation with the extrinsic arterial supply located in the epineurium. Blood flow in the vasa nervorum is neurogenically influenced (1,2). Although a recent hypothesis proposes that endoneurial blood flow is controlled by the action of autonomic nerve fibers associated with epineurial arterioles (2), our recent studies (3) show that in addition to epineurial arterioles other segments of the vasa nervorum are also innervated. In this study, we examine blood vessels of the endoneurium for possible innervation.

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Computer-Assisted Analysis of Multi-Color Confocal Microscopic Datasets: Automated Light Microscopic Discrimination of Synaptic Relationships

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163885 ◽

1996 ◽

Vol 54 ◽

pp. 284-285

Author(s):

M Wessendorf ◽

A Beuning ◽

D Cameron ◽

J Williams ◽

C Knox

Keyword(s):

Nerve Fibers ◽

Confocal Scanning Laser Microscopy ◽

Computer Assisted ◽

Nerve Terminals ◽

Neuronal Somata ◽

Scanning Laser Microscopy ◽

Confocal Scanning ◽

Entire Cell ◽

Confocal Scanning Laser ◽

Assisted Analysis

Multi-color confocal scanning-laser microscopy (CSLM) allows examination of the relationships between neuronal somata and the nerve fibers surrounding them at sub-micron resolution in x,y, and z. Given these properties, it should be possible to use multi-color CSLM to identify relationships that might be synapses and eliminate those that are clearly too distant to be synapses. In previous studies of this type, pairs of images (e.g., red and green images for tissue stained with rhodamine and fluorescein) have been merged and examined for nerve terminals that appose a stained cell (see, for instance, Mason et al.). The above method suffers from two disadvantages, though. First, although it is possible to recognize appositions in which the varicosity abuts the cell in the x or y axes, it is more difficult to recognize them if the apposition is oriented at all in the z-axis—e.g., if the varicosity lies above or below the neuron rather than next to it. Second, using this method to identify potential appositions over an entire cell is time-consuming and tedious.

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