The staining pattern of collagen fibrils. Improved correlation with sequence data.

Epiphyseal cartilage matrix contains fibrils and particles of at least 5 different types: 1. Banded collagen fibrils, present throughout the matrix, but not seen in the lacunae. 2. Non-periodic fine fibrils <100Å in diameter (Fig. 1), which are most notable in the lacunae, and may represent immature collagen. 3. Electron dense matrix granules (Fig. 1) which are often attached to fine fibrils and collagen fibrils, and probably contain protein-polysaccharide although the possibility of a mineral content has not been excluded. 4. Matrix vesicles (Fig. 2) which show a selective distribution throughout the epiphysis, and may play a role in calcification. 5. Needle-like apatite crystals (Fig. 2).Blocks of formalin-fixed epiphysis from weanling mice were digested with the following agents in 0.1M phosphate buffer: a) 5% ethylenediaminetetraacetate (EDTA) at pH 8.3, b) 0.015% bovine testicular hyaluronidase (Sigma, type IV, 750 units/mg) at pH 5.5, and c) 0.1% collagenase (Worthington, chromatograhically pure, 200 units/mg) at pH 7.4. All digestions were carried out at 37°C overnight. Following digestion tissues were examined by light and electron microscopy to determine changes in the various fibrils and particles of the matrix.

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Banded Structures in the Connective Tissue of Meningioma

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100091159 ◽

1976 ◽

Vol 34 ◽

pp. 234-235

Author(s):

C. N. Sun ◽

H. J. White

Keyword(s):

Connective Tissue ◽

Osmium Tetroxide ◽

Uranyl Acetate ◽

Collagen Fibrils ◽

Lead Citrate ◽

Connective Tissues ◽

Native Collagen ◽

Routine Procedures

Previously, we have reported on extracellular cross-striated banded structures in human connective tissues of a variety of organs (1). Since then, more material has been examined and other techniques applied. Recently, we studied a fibrocytic meningioma of the falx. After the specimen was fixed in 4% buffered glutaraldehyde and post-fixed in 1% buffered osmium tetroxide, other routine procedures were followed for embedding in Epon 812. Sections were stained with uranyl acetate and lead citrate. There were numerous cross striated banded structures in aggregated bundle forms found in the connecfive tissue of the tumor. The banded material has a periodicity of about 450 Å and where it assumes a filamentous arrangement, appears to be about 800 Å in diameter. In comparison with the vicinal native collagen fibrils, the banded material Is sometimes about twice the diameter of native collagen.

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Scanning electron microscopic study of collagen fibrillogenesis and extracellular compartmentalization in the chick embryo tendon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142669 ◽

1986 ◽

Vol 44 ◽

pp. 208-209

Author(s):

Grace C.H. Yang

Keyword(s):

Chick Embryo ◽

Extracellular Space ◽

Fibroblast Cell ◽

Collagen Fibrils ◽

Electron Microscopic ◽

Voltage Electron ◽

Scanning Electron Microscopic Study ◽

Microscopic Studies ◽

And Function

The size and organization of collagen fibrils in the extracellular matrix is an important determinant of tissue structure and function. The synthesis and deposition of collagen involves multiple steps which begin within the cell and continue in the extracellular space. High-voltage electron microscopic studies of the chick embryo cornea and tendon suggested that the extracellular space is compartmentalized by the fibroblasts for the regulation of collagen fibril, bundle, and tissue specific macroaggregate formation. The purpose of this study is to gather direct evidence regarding the association of the fibroblast cell surface with newly formed collagen fibrils, and to define the role of the fibroblast in the control and the precise positioning of collagen fibrils, bundles, and macroaggregates during chick tendon development.

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The staining pattern of the tropomyosin sequence is displayed in a new paracrystal

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142372 ◽

1986 ◽

Vol 44 ◽

pp. 150-151

Author(s):

M.K. Lamvik ◽

L.L. Klatt

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Staining Pattern ◽

Banding Patterns ◽

Mass Thickness ◽

New Form

Tropomyosin paracrystals have been used extensively as test specimens and magnification standards due to their clear periodic banding patterns. The paracrystal type discovered by Ohtsuki1 has been of particular interest as a test of unstained specimens because of alternating bands that differ by 50% in mass thickness. While producing specimens of this type, we came across a new paracrystal form. Since this new form displays aligned tropomyosin molecules without the overlaps that are characteristic of the Ohtsuki-type paracrystal, it presents a staining pattern that corresponds to the amino acid sequence of the molecule.

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Platelet Adhesion to Native Collagens Involves Proteoglycans and May Be a Two-Step Process

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645970 ◽

1987 ◽

Vol 58 (02) ◽

pp. 786-789 ◽

Cited By ~ 5

Author(s):

O Behnke

Keyword(s):

Electron Microscope ◽

Platelet Adhesion ◽

Close Contact ◽

Blood Platelets ◽

Collagen Fibrils ◽

Platelet Membrane ◽

Step Process ◽

Rat Blood ◽

Wide Gap ◽

Rat Tail

SummaryAdhesion of rat blood platelets to native rat tail collagen fibrils was studied in the electron microscope under conditions that preserved collagen-associated proteoglycans (CAPG). The CAPG molecules were aligned in chain-like configurations that encircled the fibrils with a 65 nm period; they appeared to coat the fibrils completely and extended 60-100 nm away from the fibril. The initial platelet-fibril contact occurred between the platelet glycocalyx and the CAPG of the fibrils i.e. between two surfaces with net-negative charges. When close contact was established between the fibril surface proper and the platelet membrane, CAPG were not identified in the area of contact, and the collagen-platelet distance was reduced to a ~10-12 nm wide gap traversed by delicate links in register with fibril periodicities.

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