摘要:

The purpose of this study was to modify the gold chloride procedure for studies of total innervation in corneal whole mounts to provide a decrease in nonspecific background staining and to eliminate the progressively deteriorating stain quality of standard gold chloride techniques. Modifications included use of cryo-protective agents, mechanical removal of Descemet's membrane-endothelium complex prior to fixation, treatment with alpha amylase, and halting the reduction of gold chloride to metallic gold using Kodak rapid fixer with hardener. Rat corneas were stored at-70 C in O. C.T. compound. The Descemet's membrane-endothelium complex was removed after thawing, and corneas were fixed in 4% NaPO4-buffered paraformaldehyde with 8% sucrose. Fixed corneas were incubated in NaPO4-buffered saline containing alpha amylase, placed in 100% lemon juice, then in 1% gold chloride solution, transferred to glacial acidic acid, placed in rapid fixer, rinsed in NaPO4-buffered saline, and dehydrated in graded alcohols. Flat mounts of whole corneas were examined using contralateral corneas as controls. Freezing corneas in O. C.T. compound, removal of the Descemet's membrane-endothelium complex, and treatment with alpha amylase reduced nonspecific background staining compared to controls. Treatment with Kodak rapid fixer prevented the deterioration of staining quality for at least 8 months. These improvements allow the gold chloride technique to be used with immunohisto-chemical procedures where the reaction products would be obscured by background staining.

ISSN:1052-0295    

DOI:10.3109/10520299509108333

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor

摘要:

Standardized postembedding immunoelectron microscopy was performed to demonstrate glial fibrillary acidic protein (GFAP) and vimentin in individual intermediate filaments to determine the diagnostic value of demonstrating ultrastructural and immunophenotypic characteristics of intermediate filaments in routine brain biopsy specimens. Dual expression of GFAP and vimentin was observed in the astroblastoma and astrocytes of Alexander's disease. The antigen availability for vimentin, however, was too low to allow reliable assessment of the GFAP:vimentin ratio in individual intermediate filaments and/or filament bundles. In meningioma, only vimentin positive intermediate filaments were found. GFAP positive intermediate filaments were present in all other specimens except the oligodendroglial components of the mixed glioma, which were devoid of intermediate filaments. GFAP positivity in the filamentous periphery and electron-dense core of Rosenthal fibers was demonstrated. Technical and tissue processing factors had a significant effect on particle density values obtained for individual specimens. Although the number, distribution, and density of glial intermediate filaments varies in different astroglial entities, correlation of particle density values determined by immunoelectron microscopy with relative GFAP concentrations in different lesions requires utmost caution. Nevertheless, application of the postembedding approach to routinely fixed biopsy specimens indicated an association of different entities with the exclusive presence of GFAP and/or vimentin in individual intermediate filaments, thus emphasizing the diagnostic value of intermediate filament typing for pathological characterization.

ISSN:1052-0295    

DOI:10.3109/10520299509108334

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor

摘要:

Fluorescence microscopy of caudal epididymal spermatozoa stained with 3, 3′dihexyloxacarbocyanine iodide (DiOC6(3)) showed intense fluorescence along the concave surface of the apical hook of spermatozoa ofRattusspecies and along the upper concave margin of the sperm head inMus musculusIn the spermatozoa ofHydromys chrysogaster, Melomys cervinipes, andPseudomys australis, the two ventral processes also fluoresced brightly. InP. australis, fluorescence in the apical hook of sperm heads was largely localized to its upper and lower surfaces. The sperm ofN. alexisdid not show consistent positive fluorescence. The localization of fluorescence in these spermatozoa after staining with DiOC6(3) was mainly restricted to regions where a large accumulation of perinuclear theca material lies beneath the plasmalemma. The reason for this remains to be determined, but DiOC6(3) may be useful for quickly demonstrating areas of abundant perinuclear thecal material in sperm heads of eutherian mammals by light microscopy.

ISSN:1052-0295    

DOI:10.3109/10520299509108335

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor

摘要:

Simple methods for preparing large numbers of grids exhibiting excellent coverage of intact replicas on mixed cellulose ester or polycarbonate membrane filters are described. The techniques ensure that grids and carbon replicas receive identical treatment and are not rearranged or lost during processing. The techniques permit grids and filter sections to be handled en masse rather than individually. Also, replica section squares remain centered on the grids. A temporary grid storage method (“grid- pad”) is also described, which facilitates grid identification and handling.

ISSN:1052-0295    

DOI:10.3109/10520299509108336

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor

摘要:

Silver staining of nucleolar organizing regions (NOR) is common, but a standard protocol is lacking. A modification of a rapid silver nitrate staining technique for NORs is presented here. Advantages of the modified technique include reliability, speed, cost and the fact that it can be carried out in the light.

ISSN:1052-0295    

DOI:10.3109/10520299509108337

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor