Floral ontogeny and an interpretation of the inferior ovary in Agave parryi

1969 ◽  
Vol 47 (1) ◽  
pp. 23-26 ◽  
Author(s):  
H. Lloyd Mogensen
Keyword(s):  
Three Dimensional ◽  
Serial Sections ◽  
Floral Ontogeny ◽  
Inferior Ovary ◽  
Floral Primordia ◽  
Floral Vasculature

A study of the histogenesis of the flower of Agave parryi was made using serial sections as well as three-dimensional views of dissected floral primordia. It is shown that floral ontogeny supports the appendicular interpretation of the inferior ovary of Agave parryi in that the flower parts do not arise from a smooth, ring-like meristem located at the tip of the pedicel but, rather, the flower parts arise as separate primordia. This study corroborates an investigation by Kaplan which shows that ontogeny can be used to support, rather than contradict, floral vasculature in interpreting the appendicular nature of the inferior ovary.

Three-Dimensional Reconstruction Using Stereo Pairs from Serial Thick Sections

1977 ◽  
Vol 35 ◽  
pp. 562-563
Author(s):  
Robert Glaeser ◽  
Thomas Bauer ◽  
David Grano
Keyword(s):  
Three Dimensional ◽  
Dimensional Structure ◽  
Serial Sections ◽  
Thin Sections ◽  
3 Dimensional ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Dimensional Reconstruction ◽  
Stereo Imagery ◽  
Whole Mounts

In transmission electron microscopy, the 3-dimensional structure of an object is usually obtained in one of two ways. For objects which can be included in one specimen, as for example with elements included in freeze- dried whole mounts and examined with a high voltage microscope, stereo pairs can be obtained which exhibit the 3-D structure of the element. For objects which can not be included in one specimen, the 3-D shape is obtained by reconstruction from serial sections. However, without stereo imagery, only detail which remains constant within the thickness of the section can be used in the reconstruction; consequently, the choice is between a low resolution reconstruction using a few thick sections and a better resolution reconstruction using many thin sections, generally a tedious chore. This paper describes an approach to 3-D reconstruction which uses stereo images of serial thick sections to reconstruct an object including detail which changes within the depth of an individual thick section.

Correlated Studies of Cellular Interactions Using TEM, Freeze Etching, and SEM

1974 ◽  
Vol 32 ◽  
pp. 320-321
Author(s):  
J. P. Revel
Keyword(s):  
Developmental Stages ◽  
Three Dimensional ◽  
Cell Movement ◽  
Cellular Interactions ◽  
Serial Sections ◽  
Cell Sheets ◽  
Freeze Etching ◽  
Early Developmental

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.

Application of stereological analysis of cell volume to isolated myocytes in culture with and without adrenergic innervation

1990 ◽  
Vol 48 (3) ◽  
pp. 416-417
Author(s):  
Jane K. Rosenthal ◽  
Dianne L. Atkins ◽  
William J. Marvin ◽  
Penny A. Krumm
Keyword(s):  
Cardiac Myocytes ◽  
Structural Changes ◽  
Three Dimensional ◽  
Adrenergic Innervation ◽  
Culture Cell ◽  
Serial Sections ◽  
Newborn Rats ◽  
Primary Culture Cell ◽  
Biological Studies ◽  
Cell Volumes

To comprehend structural changes in cardiac myocytes accompanying adrenergic innervation, it is essential that a three dimensional analysis be performed. To date, biological studies which utilize stereological methods have been limited to cells in tissue and in organs. Our laboratory has utilized current stereological techniques for measuring absolute volumes of individual myocytes in primary culture. Cell volumes are calculated for two distinct groups of cells at 96 hours in culture: isolated myocytes and myocytes innervated with adrenergic neurons (Figure 1).Cardiac myocytes are cultured from the ventricular apices of newborn rats. Cells are plated directly onto tissue culture dishes with or without preplated explants from the paravertebral thoracolumbar sympathetic chain. On day four cultures are photographed and marked for one-to-one cell location. Following conventional fixation and embeddment in eponate-12, the cells are relocated and mounted for microtomy. The cells are completely sectioned at 120nm in their parallel orientation to the surface of the dish (Figure 2). Serial sections are collected on formvar coated slotted grids and are recorded in sequence.

scholarly journals Anatomical basis for cell transplantation into mouse seminiferous tubules

Reproduction ◽  
2012 ◽  
Vol 144 (3) ◽  
pp. 385-392 ◽  
Author(s):  
Unai Silván ◽  
Juan Aréchaga
Keyword(s):  
Electron Microscopy ◽  
Cell Transplantation ◽  
Soft Tissues ◽  
Partial Information ◽  
Three Dimensional ◽  
Seminiferous Tubules ◽  
Serial Sections ◽  
Pathological Conditions ◽  
Anatomical Basis ◽  
Scanning Electron

Cell transplantation into the seminiferous tubules is a useful technique for the study of physiological and pathological conditions affecting the testis. However, the precise three-dimensional organization and, particularly, the complex connectivity of the seminiferous network have not yet been thoroughly characterized. To date, the technical approaches to address these issues have included manual dissection under the stereomicroscope, reconstruction of histological serial sections, and injection of contrast dyes, but all of them have yielded only partial information. Here, using an approach based on the microinjection of a self-polymerizing resin followed by chemical digestion of the surrounding soft tissues, we reveal fine details of the seminiferous tubule scaffold and its connections. These replicas of the testis seminiferous network were studied by scanning electron microscopy. The present results not only establish a morphological basis for more precise microinjection into the mouse seminiferous tubules but also enable a more profound investigation of physiological and embryological features of the testis.

scholarly journals Three-dimensional ultrastructure of a unicellular cyanobacterium.

1983 ◽  
Vol 97 (3) ◽  
pp. 713-722 ◽  
Author(s):  
S A Nierzwicki-Bauer ◽  
D L Balkwill ◽  
S E Stevens
Keyword(s):  
Inclusion Bodies ◽  
Cytoplasmic Membrane ◽  
Three Dimensional ◽  
Thylakoid Membranes ◽  
Serial Sections ◽  
Unicellular Cyanobacterium ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
Inner Surface ◽  
Computer Aided

The first complete three-dimensional ultrastructural reconstruction of a cyanobacterium was accomplished with high-voltage electron microscopy and computer-aided assembly of serial sections. The precise arrangement of subcellular features within the cell body was very consistent from one cell to another. Specialized inclusion bodies always occupied specific intracellular locations. The photosynthetic thylakoid membranes entirely surrounded the central portion of the cytoplasm, thereby compartmentalizing it from the rest of the cell. The thylakoid membranes formed an interconnecting network of concentric shells, merging only at the inner surface of the cytoplasmic membrane. The thylakoids were in contact with the cytoplasmic membrane at several locations, apparently to maintain the overall configuration of the thylakoid system. These results clarified several unresolved issues regarding structure-function relationships in cyanobacteria.

scholarly journals ULTRASTRUCTURAL INTERRELATIONSHIPS OF NERVE PROCESSES AND SMOOTH MUSCLE CELLS IN THREE DIMENSIONS

1966 ◽  
Vol 28 (1) ◽  
pp. 37-49 ◽  
Author(s):  
J. C. Thaemert
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Osmium Tetroxide ◽  
Three Dimensional ◽  
Muscle Cells ◽  
Uranyl Acetate ◽  
Intestinal Wall ◽  
Three Dimensions ◽  
Serial Sections ◽  
Muscularis Externa

The muscularis externa of the intestinal wall of frogs was fixed in osmium tetroxide, embedded in Vestopal-W, serially sectioned for electron microscopy, and stained with uranyl acetate. A method to obtain individually mounted and properly positioned serial sections is described. The three-dimensional techniques used during the course of this investigation demonstrate that it is possible to examine carefully relatively large areas of tissue on individual serial sections with the electron microscope and subsequently to construct montages of electron micrographs of pertinent areas from each section. Several carefully rendered interrelationships of nerve processes and smooth muscle cells in three dimensions are exhibited and described. Recent studies of other neuro-effector relationships are discussed in relation to the present status of the nature and organization of the autonomic nervous system in visceral organs.

scholarly journals Microtubular apparatus of melanophores: three dimensional organization

1978 ◽  
Vol 76 (3) ◽  
pp. 605-614 ◽  
Author(s):  
M Schliwa
Keyword(s):  
Three Dimensional ◽  
Cell Process ◽  
Serial Sections ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Cell Region ◽  
Thin Sectioning ◽  
A Cell ◽  
Central Apparatus ◽  
Pterophyllum Scalare

Microtubular organization in the melanophores of the angelfish, Pterophyllum scalare, has been studied by serial thin sectioning. The course of microtubules has been followed in sets of transverse serial sections taken from the centrosphere and a segment of a cell process, respectively. Microtubules arise from a prominent zone in the cell center, the central apparatus, which is composed of numerous, small, electron-dense aggregates. the number of these loosely distributed densities is highest in the center of the centrosphere, but they may also be found at its periphery. Microtubules insert into, or becomes part of, the dense material, or at least start in its vicinity. Dense aggregates may be separated from centrioles by several micrometers rather than only being closely associated with these organelles. At some distance from the organizing zone, most of the microtubules gradually assume a cortical arrangement, i.e., take a course within about 100 nm of the limiting membrane. Serial sections were used to trace all microtubules within a 6μm-long segment of a cell process. 94 percent of the microtubules observed in this segment run its entire length; it is conceivable, therefore that a considerable number of microtubules extend between the initiating site in the centrosphere and the outermost cell region. A three-dimensional model of the 6μm-long segment reveals that, despite changes in the cell process outline, microtubules maintain a strictly cortical arrangement which gives the impression of a microtubule "palisade" lining the cortex of the cell process. The features of the microtubular apparatus of angelfish melanophores are discussed in relation to factors controlling microtubule initiation and distribution.

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