Ultrastructural Immunocytochemistry of Five Rat Pituitary Adenomas

1980 ◽  
Vol 38 ◽  
pp. 724-725
Author(s):  
D. J. McComb ◽  
N. Ryan ◽  
E. Horvath ◽  
K. Kovacs ◽  
E. Nagy ◽  
...  
Keyword(s):  
Pituitary Adenomas ◽  
Pituitary Tumors ◽  
Electron Microscopic ◽  
Electron Microscopic Immunocytochemistry ◽  
Transmission Electron ◽  
Rat Pituitary ◽  
Radiation Induced ◽  
Group 5 ◽  
Group 2 ◽  
Microscopic Techniques

Conventional light and electron microscopic techniques failed to clarify the cellular composition and derivation of spontaneous and induced, intrasellar and transplanted pituitary adenomas in rats (1). In the present work, electron microscopic immunocytochemistry was applied to evaluate five adenohypo-physial tumors using a technique described by Moriarty and Garner (2). Spontaneously occurring pituitary adenomas (group 1) were harvested from aging female Long-Evans rats. R-Amsterdam rats were treated with 2 x 1.0 mg estrone acetate (HogivaI) s.c. weekly for 6 months. Pituitary adenomas in excess of 30 mg were removed from these animals to make up the tumors of group 2. Groups 3 and 4 consisted of estrogen-induced autonomous transplan¬ted pituitary tumors MtT.WlO and MtT.F4. Group 5 was a radiation-induced transplanted autonomous pituitary tumor MtT.W5. The tumors of groups 3,4 and 5 were allowed to proliferate in host rats 6-8 weeks prior to removal for processing. Tissue was processed for transmission electron microscopy (glutaraldehyde fixation, OsO4 postfixation and epoxy resin embedding), and electron microscopic immunocytochemistry (3% paraformaldehyde fixation and Araldite embedding).

scholarly journals Subcellular distribution of secretogranins I and II in GH3 rat tumoral prolactin (PRL) cells as revealed by electron microscopic immunocytochemistry.

1989 ◽  
Vol 37 (9) ◽  
pp. 1329-1336 ◽  
Author(s):  
C Tougard ◽  
L E Nasciutti ◽  
R Picart ◽  
A Tixier-Vidal ◽  
W B Huttner
Keyword(s):  
Electron Microscope ◽  
Secretory Granules ◽  
Hormone Treatment ◽  
Pituitary Cell ◽  
Gh3 Cells ◽  
Cell Models ◽  
Electron Microscopic ◽  
Electron Microscopic Immunocytochemistry ◽  
Normal Cells ◽  
Rat Pituitary

The GH3 rat pituitary cell line which secretes prolactin (PRL) is characterized by the paucity and small size of secretory granules. We looked for the presence, in these cells and in normal PRL cells, of two acidic tyrosine-sulfated proteins which are widely distributed in dense-core secretory granules of endocrine and neuronal cells, secretogranins I and II, using immunofluorescence and electron microscope immunoperoxidase techniques. Both secretogranins were detected in secretory granules of GH3 cells and of normal cells. Moreover, with our pre-embedding approach, secretogranins were localized within some RER cisternae and within all sacules of the Golgi stacks in both PRL cell models. A few small vesicles, large dilated vacuolar or multivesicular structures, and some lysosome-like structures were also immunoreactive. Double localization of secretogranins and PRL performed on GH3 cells by immunofluorescence indicated that all cells contained secretogranins I and II, whereas only 50-70% of the cells contained PRL. Moreover, in the case of hormone treatment known to increase the number of secretory granules, most if not all mature secretory granules were immunoreactive for secretogranins, whereas in certain cells some of the granules were apparently not immunoreactive for PRL. These immunocytochemical observations show that GH3 cells, which under normal conditions form only a small number of secretory granules, produce secretogranins and package them into these granules.

Urinary stone analysis

1988 ◽  
Vol 46 ◽  
pp. 86-87
Author(s):  
Saeed R. Khan
Keyword(s):  
Careful Analysis ◽  
Urinary Stone ◽  
Crystal Nucleation ◽  
Morphological Examination ◽  
Electron Microscopic ◽  
Medical Regimen ◽  
Transmission Electron ◽  
Chemical Conditions ◽  
Sticky Tape ◽  
Microscopic Techniques

Since crystalline composition of a urinary stone is an expression of urinary chemical conditions prevalent at the time of crystal nucleation and growth, a careful analysis of the stone and identification of constituent crystals is necessary for an understanding of the disease and the initiation of a proper medical regimen for the prevention of stone recurrence. Of the number of methods available, analytical electron microscopic techniques including scanning (SEM) and transmission electron microscopy (TEM), x-ray microanalysis (XRMA), and electron diffraction (ED) are gaining in popularity.For SEM, the dried stone is fractured through the middle and small pieces representing different areas of the stone are mounted on a carbon planchet or an aluminum stub using a double sticky tape or graphite paint. The specimen is then sputter coated with silver, gold or gold/palladium; or coated with carbon. For morphological examination alone, the specimen can be coated with any of the available conducting substances, but for XRMA the specimen should either be examined uncoated or be coated with carbon, or with a substance whose peaks in the XRMA spectrum do not interfere with the peaks of the elements of interest.

Immunodetection of G proteins in human pituitary adenomas: evidence for a low expression of proteins of the Gi subfamily

1997 ◽  
pp. 482-489 ◽  
Author(s):  
E Ballare ◽  
S Mantovani ◽  
M Bassetti ◽  
A Lania ◽  
A Spada
Keyword(s):  
G Proteins ◽  
Pituitary Adenomas ◽  
Pituitary Tumors ◽  
Cell Periphery ◽  
Human Pituitary ◽  
Weak Band ◽  
Rat Pituitary ◽  
Normal Human ◽  
Gs Alpha ◽  
Low Expression

G proteins mediate signal transduction in a variety of cell systems. As the expression of these proteins has not yet been investigated in detail in human pituitary tumors, we evaluated the presence of G proteins in a series of tumors including six non-functioning adenomas, five GH-secreting adenomas, three prolactinomas and one TSH-secreting adenoma, using immunoblotting and immunohistochemistry. By immunoblotting, Gi1/2alpha was undetectable in six and barely detectable in nine tumors. A similar pattern of expression was observed by probing with the antibody to Gi3alpha, which detected a very weak band in 11 tumors and no protein in four. In contrast, using large amounts of membrane proteins (40 microg), both Gi1/2alpha and Gi3alpha were detected, although at very low levels, in the negative tumors. The low expression of these proteins appeared to be specific to tumoral tissues, as both Gi1/2alpha and Gi3alpha were abundant in normal human and rat pituitary. In all tumors, Go alpha, the two Gs alpha forms, Gq/11 and G beta were present in significant amounts. Semiquantitative analysis indicated that Gs alpha was clearly detected when 2.5 microg loaded proteins were used, whereas Gi1/2alpha and Gi3alpha were barely detected with 5 microg. By immunofluorescence, all tumors studied were markedly positive for Gs alpha that was immunolocalized at the cell periphery, whereas they showed a weak positivity for Gi1/2alpha and Gi3alpha. The study is the first to provide evidence for a low expression of Gi proteins, which are involved in the transduction of inhibitory signals, in pituitary adenomas.

scholarly journals Effectiveness of different irrigation systems on smear layer removal: A scanning electron microscopic study

2014 ◽  
Vol 08 (01) ◽  
pp. 053-057 ◽  
Author(s):  
Fuat Ahmetoglu ◽  
Ali Keles ◽  
Muhammet Yalcin ◽  
Neslihan Simsek
Keyword(s):  
Irrigation System ◽  
Statistical Significance ◽  
Smear Layer ◽  
Electron Microscopic ◽  
Sem Images ◽  
Group 4 ◽  
Scanning Electron Microscopic Study ◽  
Ultrasonic Irrigation ◽  
Group 5 ◽  
Group 2

ABSTRACT Objectives: To evaluate effectiveness of the apical negative pressure irrigation (EndoVac), passive ultrasonic irrigation (PUI), and conventional needle irrigation (CI) systems on smear layer (SR) removal. Materials and Methods: Sixty single-rooted canines were prepared using NiTi rotary files and subjected to different irrigation regimens: EndoVac with NaOCl (Group 1) or NaOCl/EDTA (Group 2); PUI with NaOCl (Group 3) or NaOCl/EDTA (Group 4); CI with NaOCl (Group 5) or NaOCl/EDTA (Group 6). The roots were split longitudinally. SEM images were taken to evaluate the amount of residual SR. Results: In Groups 1, 3, and 5, there was no removal of SR (P > 0.05). The coronal thirds within Groups 2, 4, and 6 were cleaned completely, but the middle and the apical thirds was achieved partially or completely (P > 0.05). Conclusion: Regardless of which irrigation system was used, the use of NaOCl alone failed to remove the SR. In NaOCl/EDTA combination groups, the SR was removed partially or completely and no statistical significance. This study demonstrated that in order to remove the SR should be used EDTA solution for final irrigation in the root canal, regardless of the technique in each of the three.

THE SIZE OF GROWTH HORMONE GRANULES IN PITUITARY ADENOMAS PRODUCING ACROMEGALY

1977 ◽  
Vol 84 (3) ◽  
pp. 461-469 ◽  
Author(s):  
Alex M. Landolt ◽  
Verena Rothenbühler
Keyword(s):  
Pituitary Adenomas ◽  
Entire Group ◽  
Electron Microscopic ◽  
Retrospective Diagnosis ◽  
Hormone Synthesis ◽  
Large Numbers ◽  
Functional Factors ◽  
The Mean ◽  
Hormone Granules ◽  
Microscopic Techniques

ABSTRACT Measurements of the diameters of large numbers of granules in electron micrographs of pituitary adenomas in cases of acromegaly do not show that a typical size exists which allows of the retrospective diagnosis of the hormone secreted by the tumour. The granule diameters found in single cases show a normal distribution. The average values determined in 19 unselected cases of acromegaly range between 160 and 342 nm. They are also normally distributed about the mean for the entire group which is 238 nm. With histo-immunological electron microscopic techniques hGH can be demonstrated in small, medium and large granules. The size of hormone granules is determined by functional factors such as the speed of hormone synthesis and hormone release but not by the type of hormone secreted.

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