Effects of varenicline on lung tissue in the animal model

Gonadotroph cell adenomas of the pituitary are infrequent in human patients and are not invariably associated with altered gonadal function. To date, no animal model of this tumor type exists. Herein, we describe spontaneous gonadotroph cell adenomas in old male and female Sprague-Dawley rats by histology, immunocytology and electron microscopy.The material consisted of the pituitaries of 27 male and 38 female Sprague Dawley rats, all 26 months of age or older, removed at routine autopsy. Sections of formal in-fixed, paraffin-embedded tissue were stained with hematoxylin-phloxine-saffron (HPS), the PAS method and the Gordon-Sweet technique for the demonstration of reticulin fibers. For immunostaining, sections were exposed to anti-rat β-LH, anti-ratβ-TSH, anti-rat PRL, anti-rat GH and anti-rat ACTH 1-39. For electron microscopy, tissue was fixed in 2.5% glutaraldehyde, postfixed in 1% OsO4 and embedded in epoxy-resin. Tissue fixed in 10% formalin, embedded in epoxy resin without osmification, was used for immunoelectron microscopy.

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Electron Microscopic Detection and Characterization of Nonhuman Primate Enteric Viruses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054145 ◽

1982 ◽

Vol 40 ◽

pp. 306-307

Author(s):

G. C. Smith ◽

R. L. Heberling ◽

S. S. Kalter

Keyword(s):

Electron Microscopy ◽

Animal Model ◽

Nonhuman Primate ◽

Clinical Condition ◽

Intestinal Tract ◽

Enteric Viruses ◽

Electron Microscopic ◽

Microscopic Detection

A number of viral agents are recognized as and suspected of causing the clinical condition “gastroenteritis.” In our attempts to establish an animal model for studies of this entity, we have been examining the nonhuman primate to ascertain what viruses may be found in the intestinal tract of “normal” animals as well as animals with diarrhea. Several virus types including coronavirus, adenovirus, herpesvirus, and picornavirus (Table I) were detected in our colony; however, rotavirus, astrovirus, and calicivirus have not yet been observed. Fecal specimens were prepared for electron microscopy by procedures reported previously.

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Isolation of Asbestos from Lung Tissue and Sputum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054261 ◽

1982 ◽

Vol 40 ◽

pp. 330-331

Author(s):

M. G. Williams ◽

C. Corn ◽

R. F. Dodson ◽

G. A. Hurst

Keyword(s):

Sodium Hypochlorite ◽

Lung Tissue ◽

Body Fluids ◽

Unknown Etiology ◽

The Past

During this century, interest in the particulate content of the organs and body fluids of those individuals affected by pneumoconiosis, cancer, or other diseases of unknown etiology developed and concern was further prompted with the increasing realization that various foreign particles were associated with or caused disease. Concurrently particularly in the past two decades, a number of methods were devised for isolating particulates from tissue. These methods were recently reviewed by Vallyathan et al. who concluded sodium hypochlorite digestion was both simple and superior to other digestion procedures.

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In situ microprobe quantitation of inorganic particle burden in paraffin sections of lung tissue

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107010 ◽

1988 ◽

Vol 46 ◽

pp. 990-991

Author(s):

Jerrold L. Abraham

Keyword(s):

Lung Tissue ◽

Quantitative Information ◽

Particulate Material ◽

Paraffin Sections ◽

Tissue Samples ◽

Qualitative And Quantitative ◽

The Past ◽

Quantitative Analyses ◽

Data Result

Inorganic particulate material of diverse types is present in the ambient and occupational environment, and exposure to such materials is a well recognized cause of some lung disease. To investigate the interaction of inhaled inorganic particulates with the lung it is necessary to obtain quantitative information on the particulate burden of lung tissue in a wide variety of situations. The vast majority of diagnostic and experimental tissue samples (biopsies and autopsies) are fixed with formaldehyde solutions, dehydrated with organic solvents and embedded in paraffin wax. Over the past 16 years, I have attempted to obtain maximal analytical use of such tissue with minimal preparative steps. Unique diagnostic and research data result from both qualitative and quantitative analyses of sections. Most of the data has been related to inhaled inorganic particulates in lungs, but the basic methods are applicable to any tissues. The preparations are primarily designed for SEM use, but they are stable for storage and transport to other laboratories and several other instruments (e.g., for SIMS techniques).

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Neurofilaments and Paired Helical Filaments

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120357 ◽

1985 ◽

Vol 43 ◽

pp. 740-743

Author(s):

J. Metuzals

Keyword(s):

Animal Model ◽

Posttranslational Modifications ◽

Posttranslational Modification ◽

Giant Axon ◽

Paired Helical Filaments ◽

Squid Giant Axon ◽

In Vitro Experiments ◽

Thin Sections ◽

Structural Relationships

It has been demonstrated that the neurofibrillary tangles in biopsies of Alzheimer patients, composed of typical paired helical filaments (PHF), consist also of typical neurofilaments (NF) and 15nm wide filaments. Close structural relationships, and even continuity between NF and PHF, have been observed. In this paper, such relationships are investigated from the standpoint that the PHF are formed through posttranslational modifications of NF. To investigate the validity of the posttranslational modification hypothesis of PHF formation, we have identified in thin sections from frontal lobe biopsies of Alzheimer patients all existing conformations of NF and PHF and ordered these conformations in a hypothetical sequence. However, only experiments with animal model preparations will prove or disprove the validity of the interpretations of static structural observations made on patients. For this purpose, the results of in vitro experiments with the squid giant axon preparations are compared with those obtained from human patients. This approach is essential in discovering etiological factors of Alzheimer's disease and its early diagnosis.

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Membrane-associated microtubular areays induced in proximal myelinated processes of dorsal root ganglia by large doses of vitamin B6

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143468 ◽

1986 ◽

Vol 44 ◽

pp. 368-369

Author(s):

V.J. Montpetit ◽

S. Dancea ◽

L. Tryphonas ◽

D.F. Clapin

Keyword(s):

Animal Model ◽

Endoplasmic Reticulum ◽

Dorsal Root Ganglia ◽

Rough Endoplasmic Reticulum ◽

Dorsal Root ◽

Vitamin B6 ◽

Morphological Changes ◽

Model System ◽

Sensory Nerves ◽

Peripheral Sensory

Very large doses of pyridoxine (vitamin B6) are neurotoxic in humans, selectively affecting the peripheral sensory nerves. We have undertaken a study of the morphological and biochemical aspects of pyridoxine neurotoxicity in an animal model system. Early morphological changes in dorsal root ganglia (DRG) associated with pyridoxine megadoses include proliferation of neurofilaments, ribosomes, rough endoplasmic reticulum, and Golgi complexes. We present in this report evidence of the formation of unique aggregates of microtubules and membranes in the proximal processes of DRG which are induced by high levels of pyridoxine.

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Paired helical filaments (PHF) in rats: An experimental animal model for Alzheimer's disease

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128493 ◽

1987 ◽

Vol 45 ◽

pp. 842-843

Author(s):

V.J.A. Montpetit ◽

S. Dancea ◽

S.W. French ◽

D.F. Clapin

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Animal Model ◽

Paired Helical Filaments ◽

Ethanol Intoxication ◽

Drg Neurons ◽

Critical Difference ◽

Suitable Animal Model ◽

The Central Nervous System ◽

Chronic Ethanol Intoxication

A continuing problem in Alzheimer research is the lack of a suitable animal model for the disease. The absence of neurofibrillary tangles of paired helical filaments is the most critical difference in the processes by which the central nervous system ages in most species other than man. However, restricting consideration to single phenomena, one may identify animal models for specific aspects of Alzheimer's disease. Abnormal fibers resembling PHF have been observed in dorsal root ganglia (DRG) neurons of rats in a study of chronic ethanol intoxication and spontaneously in aged rats. We present in this report evidence that PHF-like filaments occur in ethanol-treated rats of young age. In control animals lesions similar in some respects to our observations of cytoskeletal pathology in pyridoxine induced neurotoxicity were observed.Male Wistar BR rats (Charles River Labs) weighing 350 to 400 g, were implanted with a single gastrostomy cannula and infused with a liquid diet containing 30% of total calories as fat plus ethanol or isocaloric dextrose.

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The Identification of Phospholipid Micelles in Glutaraldehyde-Urea Embedded Tissue

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116097 ◽

1975 ◽

Vol 33 ◽

pp. 494-495

Author(s):

Daniel C. Pease

Keyword(s):

Electron Micrographs ◽

Lung Tissue ◽

Osmium Tetroxide ◽

Uranyl Acetate ◽

Type Ii ◽

Lead Citrate ◽

Phospholipid Micelles ◽

Type Ii Pneumocytes ◽

Ultrathin Sections ◽

Polar Water

It is reasonable to think that phospholipid micelles should be visible and identifiable in electron micrographs of ultrathin sections if only they can be preserved throughout the embedding process. The development of highly polar, water-containing, aminoplastic embedments has made this a likely possibility. With this in mind, an investigation of the lecithin-secreting, Type II pneumocytes of the lung is underway.Initially it has been easiest to recognize phospholipid micelles in lung tissue fixed first with glutaraldehyde, and then secondarily exposed to osmium tetroxide. However, the latter is not a necessary concomitant for micellar preservation. Conventional uranyl acetate and lead citrate staining is finally applied. Importantly, though, the micelles have been most easily seen in tissue embedded in 507. glutaraldehyde polymerized with urea, as described in detail by D.C. Pease and R.G. Peterson (J. Ultra- struct. Res., 41, 133, 1972). When oriented appropriately, the micellar units are seen as tiny, bilayer plates.

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