Freeze-fracture characterization of cell types at the surface of the taste organ of the frog,Rana esculenta

1993 ◽  
Vol 22 (2) ◽  
pp. 118-128 ◽  
Author(s):  
A. Sbarbati ◽  
C. Zancanaro ◽  
P. Ferrara ◽  
F. Franceschini ◽  
C. Accordini ◽  
...  
Keyword(s):  
Freeze Fracture ◽  
Cell Types ◽  
Rana Esculenta ◽  
Fracture Characterization ◽  
Taste Organ

Freeze-fracture characterization of ‘young’ and ‘old’ human erythrocytes

1982 ◽  
Vol 685 (2) ◽  
pp. 207-210 ◽  
Author(s):  
Kenneth H. Fischbeck ◽  
Eduardo Bonilla ◽  
Donald L. Schotland
Keyword(s):  
Freeze Fracture ◽  
Human Erythrocytes ◽  
Fracture Characterization

Characterization of germ cell nuclei in freeze-fracture replicas using seminiferous tubules isolated by transillumination

1990 ◽  
Vol 48 (3) ◽  
pp. 74-75
Author(s):  
Alfonsina Morales ◽  
Juan C. Cavicchia
Keyword(s):  
Germ Cell ◽  
Basal Lamina ◽  
Freeze Fracture ◽  
Cell Types ◽  
Pore Distribution ◽  
Seminiferous Tubules ◽  
Nuclear Pore ◽  
Cell Nuclei ◽  
Adult Rats

The present investigation was under taken, combining the identification of specific germ cell types present in a particular stage of the seminiferous wave with freeze-fracture techniques to follow the changing pattern of their nuclear pore distribution during spermatogenesis. Male albino adult rats were used. Segments of seminiferous tubules were separated (stages VII-VIII; IX-XI; XII-XIV) by a technique described by Parvinen and Vanha-Perttula where the stages of the cycle were recognized and isolated by transillumination under a dissecting microscope. The tubular segments were immediately fixed in glutaraldehyde, immersed in glycerol, freeze-fractured in a Balzers BAF 301 apparatus at-110°C and examined under a Siemens Elmiskop I EM. The only spermatogonia located in the studied stages (type A) are ovalcells in contact with the basal lamina. Pore distribution is non-random with a relatively in conspicuous aggregation. Preleptotene spermatocytes (stages VII-VIII) are easily identified by being numerous, their location over the basal lamina and the irrelatively small size. They exhibit a striking clustering of pores, in groups of 15-30 separated by pore-free areas (fig.1). Leptotenes (fig.2, 3) (stages IX-XI) and zygotenes (fig.4) (XII-XIII) change the pattern to a more even distributional though clearly maintaining some degree of clustering.

Freeze-fracture characterization of isolated myelin and axolemma membrane fractions

1981 ◽  
Vol 229 (2) ◽  
pp. 311-322 ◽  
Author(s):  
Michael J. Cullen ◽  
George H. De Vries ◽  
Henry deF. Webster
Keyword(s):  
Freeze Fracture ◽  
Fracture Characterization

Cryomicroscopy of multiphase latices

1991 ◽  
Vol 49 ◽  
pp. 1060-1061
Author(s):  
O. L. Shaffer ◽  
M.S. El-Aasser ◽  
C. L. Zhao ◽  
M. A. Winnik ◽  
R. R. Shivers
Keyword(s):  
Electron Microscopy ◽  
Radiation Damage ◽  
Freeze Fracture ◽  
Particle Morphology ◽  
Second Stage ◽  
Transmission Electron ◽  
Important Approach ◽  
Carbon Coated ◽  
Preparation Techniques

Transmission electron microscopy is an important approach to the characterization of the morphology of multiphase latices. Various sample preparation techniques have been applied to multiphase latices such as OsO4, RuO4 and CsOH stains to distinguish the polymer phases or domains. Radiation damage by an electron beam of latices imbedded in ice has also been used as a technique to study particle morphology. Further studies have been developed in the use of freeze-fracture and the effect of differential radiation damage at liquid nitrogen temperatures of the latex particles embedded in ice and not embedded.Two different series of two-stage latices were prepared with (1) a poly(methyl methacrylate) (PMMA) seed and poly(styrene) (PS) second stage; (2) a PS seed and PMMA second stage. Both series have varying amounts of second-stage monomer which was added to the seed latex semicontinuously. A drop of diluted latex was placed on a 200-mesh Formvar-carbon coated copper grid.

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