Disease relevance of Freeze Substitution

• After moderately severe edema, diagnosed on chest radiographs and with decreasing arterial pO2, lobes were fixed with glutaraldehyde and formaldehyde or by freeze substitution [1].
• The peroxidase-antiperoxidase (PAP) technique has been used to demonstrate oncomodulin in sections of Morris rat hepatomas 5123D, 5123tc, 7288Ctc, and 7777 fixed with Bouin's or Carnoy's fixatives, or using freeze substitution [2].
• The highest labeling density appeared after GA (15 min) and physical dehydration, in particular after freeze substitution [3].

High impact information on Freeze Substitution

• The glutamate transporters GLT-1 and GLAST were studied by immunogold labeling on ultrathin sections of rat brain tissue embedded in acrylic resins at low temperature after freeze substitution [4].
• Labeling with a well defined mAb and protein A-gold after freeze-substitution and low temperature embedding in Lowicryl HM20 of aldehyde-fixed and cryoprotected cells, resulted in high levels of specific labeling and excellent retention of cellular ultrastructure compared to ultra-thin cryosections [5].
• The extracellular matrix of epiphyseal cartilage tissue was preserved in a state believed to resemble closely that of native tissue following processing by high pressure freezing, freeze substitution, and low temperature embedding (HPF/FS) [6].
• To address concerns about using chemical fixation to study the membrane-bound transport of cationized ferritin, protoplasts were fixed both by conventional glutaraldehyde fixation and by rapid freezing in a Balzers high-pressure freezing apparatus (followed by freeze substitution) [7].
• Rapid freezing followed by freeze-substitution has been used to study the ultrastructure of the myosin filaments of live and demembranated frog sartorius muscle in the states of relaxation and rigor [8].

Biological context of Freeze Substitution

• Aldehyde fixation causes membrane vesiculation during platelet exocytosis: a freeze-substitution study [9].

Anatomical context of Freeze Substitution

• With tannic acid mordant after aldehyde-osmium fixation or rapid freezing and freeze-substitution, it is possible to demonstrate subtle electron-dense specializations of the astrocytic membranes and extracellular matrix in thin-sections which correspond to the sites of polygonal particle junctions [10].
• These structures are well preserved in macrophages that are physically fixed by rapid-freezing and subsequent freeze-substitution in osmium-acetone [11].
• In order to test the ability of freeze substitution to accurately preserve the ultrastructure of the actin component of the cytoskeleton, the structure of rotary shadowed actin filaments was compared following preparation by glutaraldehyde fixation and freeze etch or freeze substitution [12].
• Fluid dynamics of the excretory flow of zymogenic and mucin contents in rat gastric gland processed by high-pressure freezing/freeze substitution [13].
• Disc formation of rod photoreceptor cells in developing BALB/c mice retinas was studied by rapid freeze, freeze-substitution, freeze-etching, immunocytochemistry, and myosin S-1 decoration methods [14].

Associations of Freeze Substitution with chemical compounds

• We developed a new procedure, which entails application of high-pressure freezing followed by freeze-substitution with acetone containing uranyl acetate, followed by low temperature embedding in HM20 [15].
• Portions of muscle containing the activated spindles were quick-frozen, fixed in absolute ethanol during freeze-substitution, and then embedded in paraffin wax [16].
• To address this concern we examined activated frog nodes processed by three different methods: (i) rapid freezing/freeze-substitution, (ii) direct osmication, and (iii) primary fixation in a mixture of aldehydes and osmium [17].
• Ultrarapid freezing, followed by freeze-fracture and freeze substitution, has confirmed aspects of the proposed exocytotic sequence, suggesting that this release is not due to the application of tannic acid, and these techniques also produced further evidence for the existence of the granule-core coat [18].
• Olfactory bulbs were examined using freeze substitution, silver trapping of chloride and intensification techniques at light and electron microscopic level [19].

Gene context of Freeze Substitution

• Immuno-gold-labelling of CUT-1, CUT-2 and cuticlin epitopes in Caenorhabditis elegans and Heterorhabditis sp. processed by high pressure freezing and freeze-substitution [20].
• After vitrification, freeze-substitution and embedding of the platelets, annexin V was located on ultra thin sections, as detected by an anti-annexin V antibody and gold labelled protein A. Upon activation, the platelets show two different forms; irregular platelets with unchanged cytoplasm and round cells with apparently diluted cytoplasm [21].
• We have compared the measurement of sodium, potassium, and chloride contents in a salt tolerant unicellular alga, Dunaliella parva, following either freeze-substitution (using two different resins) or molecular distillation drying [22].
• METHODS: Thin slices of the parallel, tightly packed capillary bed of the eel rete mirabile were cryofixed and prepared for conventional TEM by freeze-substitution [23].
• In this study, we have re-examined the AA amyloid fibrils with advanced methods of cryofixation and freeze substitution which are known to retain ultrastructural detail as close as possible to the living state [24].

Analytical, diagnostic and therapeutic context of Freeze Substitution

• We conclude that freeze-substitution electron microscopy is effective in the visualization of LPS morphotypes [25].
• Cryofixation followed by freeze substitution in osmium tetroxide was evaluated as a method for preparing biological specimens for immunoelectronmicroscopy [26].
• Ciliated and microvillous structures of rat olfactory and nasal respiratory epithelia. A study using ultra-rapid cryo-fixation followed by freeze-substitution or freeze-etching [27].
• Immunoelectron microscopy of acetylcholine receptors and 43 KD protein after rapid freezing, freeze-substitution, and low-temperature embedding in lowicryl K11M [28].
• The freeze-substitution procedure yielded better chloride retention while with aldehyde fixation tissue preservation was more appropriate [29].

References