Observations on the Collagen and Proteinpolysaccharide Complex of Rabbit Corneal Stroma

1969 ◽  
Vol 4 (2) ◽  
pp. 421-436
Author(s):  
J. W. SMITH ◽  
J. FRAME
Keyword(s):  
Phosphotungstic Acid ◽  
Corneal Stroma ◽  
Uranyl Acetate ◽  
Collagen Fibrils ◽  
Bismuth Nitrate ◽  
Lead Citrate ◽  
Cross Sectional ◽  
Cross Links ◽  
Beaded Filaments ◽  
Corneal Collagen

The form and interrelationship of the collagen fibrils and proteinpolysaccharide complex of rabbit corneal stroma were studied by electron microscopy. The intact tissue was examined as Araldite sections stained with alkaline lead citrate and uranyl acetate, and the mechanically disintegrated cornea after positive or negative staining with phosphotungstic acid or after treatment with 0.5% bismuth nitrate in 0.1 M nitric acid. The corneal collagen fibrils vary in cross-sectional area from 4.6 to 9.6 x 104 sq. Å and do not exhibit a regular hexagonal distribution. Like tendon fibrils they consist of longitudinal filaments, but their appearance suggests that they lack some of the interfilament cross-links present in tendon. In sections of intact cornea and in negatively stained disintegrated cornea, filaments which are considered to be the protein cores of proteinpolysaccharide macromolecules are evident. They are about 40 Å wide and 2000 Å long. They appear to run an angular course, orthogonal to the collagen fibrils, and to be tangentially attached to several fibrils in the region of the a band. After treatment with bismuth nitrate disintegrated cornea contains coarsely beaded filaments. The filaments are about 2000 Å long and the beads about 70 Å in diameter. It is considered that these are again proteinpolysaccharide macromolecules and that each bead represents one or more polysaccharide chains in coiled configuration.

Electron Microscopy of Wound Healing in Patients with Hernia

1975 ◽  
Vol 33 ◽  
pp. 352-353
Author(s):  
C.N. Sun ◽  
H.J. White ◽  
R.C. Read
Keyword(s):  
Electron Microscopy ◽  
Wound Healing ◽  
Phosphate Buffer ◽  
Osmium Tetroxide ◽  
Phosphotungstic Acid ◽  
Rectus Sheath ◽  
Uranyl Acetate ◽  
Collagen Fibrils ◽  
Lead Citrate ◽  
Native Collagen

Previously we have reported the defect of collagen fibrils from herniated rectus sheath. This presentation includes additional sections from postsurgical incisions (10 days) from both control and hernia patients. Small pieces of rectus sheath were fixed in 3% glutaraldehyde in phosphate buffer (pH 7.2) and post fixed with buffered 2% osmium tetroxide. The tissues were then dehydrated in serially increasing concentrations of alcohol and embedded in Epon 812. Sections were stained with 2.5% phosphotungstic acid or uranyl acetate and lead citrate.Previously we found that collagen fibrils from "non-herniated" rectus sheath have uniform diameters and 640 Å periodicity with seven or more intraperiodic bands resembling typical native collagen fibrils, while the fibrils from fascia obtained from patients with direct herniation show considerable variation in diameter. These variations are often found in the same individual fibers with a range from 300 Å to 3000 Å.

Ultrastructure and Staining of Developing Elastic Tissue

1971 ◽  
Vol 29 ◽  
pp. 244-245
Author(s):  
E. N. Albert
Keyword(s):  
Fine Structure ◽  
Phosphotungstic Acid ◽  
Staining Method ◽  
Rat Aorta ◽  
Uranyl Acetate ◽  
The Other ◽  
Elastic Fibers ◽  
Elastic Tissue ◽  
Lead Citrate ◽  
New Born

Silver tetraphenylporphine sulfonate (Ag-TPPS) was synthesized in this laboratory and used as an electron dense stain for elastic tissue (Fig 1). The procedures for the synthesis of tetraphenylporphine sulfonate and the staining method for mature elastic tissue have been described previously.The fine structure of developing elastic tissue was observed in fetal and new born rat aorta using tetraphenylporphine sulfonate, phosphotungstic acid, uranyl acetate and lead citrate. The newly forming elastica consisted of two morphologically distinct components. These were a central amorphous and a peripheral fibrous. The ratio of the central amorphous and the peripheral fibrillar portion changed in favor of the former with increasing age.It was also observed that the staining properties of the two components were entirely different. The peripheral fibrous component stained with uranyl acetate and/or lead citrate while the central amorphous portion demonstrated no affinity for these stains. On the other hand, the central amorphous portion of developing elastic fibers stained vigorously with silver tetraphenylporphine sulfonate, while the fibrillar part did not (compare figs 2, 3, 4). Based upon the above observations it is proposed that developing elastica consists of two components that are morphologically and chemically different.

Banded Structures in the Connective Tissue of Meningioma

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.

‘Small’-proteoglycan: collagen interactions: Keratan sulphate proteoglycan associates with rabbit corneal collagen fibrils at the ‘a’ and ‘c’ bands

1985 ◽  
Vol 5 (9) ◽  
pp. 765-774 ◽  
Author(s):  
J. E. Scott ◽  
M. Haigh
Keyword(s):  
Binding Sites ◽  
Type I Collagen ◽  
Specific Binding ◽  
Corneal Stroma ◽  
Collagen Fibrils ◽  
Type I ◽  
Keratan Sulphate ◽  
Protein Rich ◽  
Small Proteoglycan ◽  
Corneal Collagen

l. Proteoglycans (PGs) in rabbit corneal stroma and mouse sclera have been stained for electron microscopy with Cupromeronic blue in a critical electrolyte concentration (CEC) mode, with and without prior digestion of the tissue by keratanase or chondroitinase ABC to remove the keratan sulphate (KS) or chondroitin-dermatan sulphates (CS or DS) respectively.2. Two classes of PGs, located orthogonally to the corneal collagen fibrils at either the ‘step’ (band ‘a’ or ‘c’) or gap zone (band ‘d’ or ‘e’) are shown to be KS-PGs or DS-PGs respectively. Four separate and specific PG binding sites on Type I collagen fibrils have thus been identified.3. Rabbit corneal KS and DS PGs each contain two kinds of PG (Gregory JD, Coster L & Damle SP (1982) J. Biol. Chem.257, 6965–6970). We propose that each ‘small’ protein-rich PG is associated with a specific binding site on the collagen fibril.

Observation of microtubule-like structures and crystalline array in Azotobacter vinelandii

1989 ◽  
Vol 47 ◽  
pp. 1040-1041
Author(s):  
M. S. Dobbins ◽  
M. D. Socolofsky
Keyword(s):  
Proteus Mirabilis ◽  
Phosphotungstic Acid ◽  
Azotobacter Vinelandii ◽  
Uranyl Acetate ◽  
Stereo Pair ◽  
Lead Citrate ◽  
Sodium Cacodylate ◽  
Molecule Transport ◽  
Carbon Coated ◽  
Crystalline Array

Many studies have been conducted on microtubules in eukaryotes, including protozoans, but few have dealt with similar structures in bacteria. Microtubule-1ike structures (MT) have been observed in Proteus mirabilis, Azotobacter vinelandii, and some bacterial L-forms . The function of these MT in prokaryotes is as yet undetermined. Microtubules in eukaryotes are involved in cytoskeleton support, cel1 motility, molecule transport, and the separation of chromosomes during mitosis . It has been suggested that A. vinelandii possesses forty chromosomes per cell , so this investigation speculates on the possibility these MT are involved in some form of chromosomal separation. While observing these structures a crystal lattice was noticed which has not been observed in the aforementioned prokaryotes.Cells were fixed for 10-20 min in 2% glutaraldehyde/0.1M sodium cacodylate (pH 7.2), washed with buffer, post-fixed with 1% OsO4, and stained with uranyl acetate. Samples were thin-sectioned, collected on carbon-coated parlodion- reinforced grids, and post-stained with lead citrate. Other preparations involved whole or lysed cells negatively stained with 2% phosphotungstic acid. All specimens exhibiting MT or the crystalline array were photographed in stereo pair.

Type C Virus Associated With a Gibbon APE Lymphocytic Leukemia

1976 ◽  
Vol 34 ◽  
pp. 268-269
Author(s):  
M. J. Walling ◽  
T. Aoki ◽  
R. E. Gallagher ◽  
R. C. Gallo
Keyword(s):  
Young Adult ◽  
Plasma Sample ◽  
Phosphotungstic Acid ◽  
Uranyl Acetate ◽  
Lymphocytic Leukemia ◽  
Myelogenous Leukemia ◽  
Lead Citrate ◽  
Fresh Tissue ◽  
Negative Stain ◽  
Type C

The occurrence in a gibbon ape of a lymphosarcoma and a myelogenous leukemia accompanied by the presence of a type C virus was reported by Kawakami et al. in 1972 (1). The present study was undertaken on another gibbon ape which spontaneously developed lymphosarcoma with lymphocytic leukemia. Fresh tissue was obtained by autopsy from the animal, a 7½ year old (young adult) male. A plasma sample was also taken prior to death. The whole tissue was fixed in 2.5% glutaraldehyde (buffered), postfixed in 0s04(l%) and embedded in Epon. Staining was carried out with uranyl acetate and lead citrate. The plasma was pelleted by ultracentrifugation and processed for negative stain using phosphotungstic acid. Thick sections of the Epon embedded material were taken to determine the exact area studied.

scholarly journals THE FINE STRUCTURE OF ELASTIC FIBERS

1966 ◽  
Vol 30 (1) ◽  
pp. 59-71 ◽  
Author(s):  
Theodore K. Greenlee ◽  
Russell Ross ◽  
Jerry L. Hartman
Keyword(s):  
Fine Structure ◽  
Phosphotungstic Acid ◽  
Elastic Fiber ◽  
Uranyl Acetate ◽  
Collagen Fibrils ◽  
Elastic Fibers ◽  
Specific Staining ◽  
Central Regions

The fine structure of developing elastic fibers in bovine ligamentum nuchae and rat flexor digital tendon was examined. Elastic fibers were found to contain two distinct morphologic components in sections stained with uranyl acetate and lead. These components are 100 A fibrils and a central, almost amorphous nonstaining area. During development, the first identifiable elastic fibers are composed of aggregates of fine fibrils approximately 100 A in diameter. With advancing age, somewhat amorphous regions appear surrounded by these fibrils. These regions increase in prominence until in mature elastic fibers they are the predominant structure surrounded by a mantle of 100 A fibrils. Specific staining characteristics for each of the two components of the elastic fiber as well as for the collagen fibrils in these tissues can be demonstrated after staining with lead, uranyl acetate, or phosphotungstic acid. The 100 A fibrils stain with both uranyl acetate and lead, whereas the central regions of the elastic fibers stain only with phosphotungstic acid. Collagen fibrils stain with uranyl acetate or phosphotungstic acid, but not with lead. These staining reactions imply either a chemical or an organizational difference in these structures. The significance and possible nature of the two morphologic components of the elastic fiber remain to be elucidated.

scholarly journals Polarimetric interferometry to objectively evaluate the optical properties of corneal stroma

2018 ◽  
Vol 2 (2) ◽  
pp. 36-41
Author(s):  
Eugenio Lipari ◽  
Alessandra Sborgia ◽  
Mario Nubile ◽  
Leonardo Mastropasqua ◽  
Giovanni Alessio
Keyword(s):  
Optical Properties ◽  
Early Stage ◽  
Corneal Stroma ◽  
Collagen Fibrils ◽  
New Method ◽  
Strong Impact ◽  
Corneal Disease ◽  
Non Invasive ◽  
Invasive Method ◽  
Corneal Collagen

A new non-invasive method, based on the interferometric analysis of diff ractive and polarizing effects related to the birefringent properties of corneal collagen fibrils, has been developed to objectively evaluate the optical properties of the stroma. The new method shows a relevant impact on corneal surgeries specifically for lamellar transplantation where, due to the polarizing properties of the stroma, the alignment between collagen fibrils of donor corneas with patient collagen fibril orientation has shown an improvement of visual acuity postoperatively. Further studies on the regularity of the corneal isogyre pattern are showing this new method has a strong impact in early-stage diagnosis of corneal disease.

Hepatocyte Alterations in Guinea Pigs FED Polychlorinated Biphenyls (PCBs), Dibenzodioxins (PCDD), AND DIBENZOFURANS (PCDF)

1982 ◽  
Vol 40 ◽  
pp. 56-57
Author(s):  
J. N. Turner ◽  
D. N. Collins
Keyword(s):  
Guinea Pigs ◽  
Room Temperature ◽  
Dose Group ◽  
Methyl Cellulose ◽  
Uranyl Acetate ◽  
Target Organ ◽  
Office Building ◽  
Lead Citrate ◽  
Control Groups ◽  
Cooling Fluid

A fire involving an electric service transformer and its cooling fluid, a mixture of PCBs and chlorinated benzenes, contaminated an office building with a fine soot. Chemical analysis showed PCDDs and PCDFs including the highly toxic tetra isomers. Guinea pigs were chosen as an experimental animal to test the soot's toxicity because of their sensitivity to these compounds, and the liver was examined because it is a target organ. The soot was suspended in 0.75% methyl cellulose and administered in a single dose by gavage at levels of 1,10,100, and 500mgm soot/kgm body weight. Each dose group was composed of 6 males and 6 females. Control groups included 12 (6 male, 6 female) animals fed activated carbon in methyl cellulose, 6 males fed methyl cellulose, and 16 males and 10 females untreated. The guinea pigs were sacrificed at 42 days by suffocation in CO2. Liver samples were immediately immersed and minced in 2% gluteraldehyde in cacadylate buffer at pH 7.4 and 4°C. After overnight fixation, samples were postfixed in 1% OsO4 in cacodylate for 1 hr at room temperature, embedded in epon, sectioned and stained with uranyl acetate and lead citrate.

Membranous alterations in the cytoplasm and nucleus in a primitive neuroectodermal tumor of the brain

1978 ◽  
Vol 36 (2) ◽  
pp. 628-629
Author(s):  
C. N. Sun ◽  
C. Araoz ◽  
H. J. White
Keyword(s):  
Nuclear Envelope ◽  
Tumor Cells ◽  
Osmium Tetroxide ◽  
Primitive Neuroectodermal Tumor ◽  
Uranyl Acetate ◽  
Neuroectodermal Tumor ◽  
Annulate Lamellae ◽  
Lead Citrate ◽  
Thin Sections ◽  
The Brain

The ultrastructure of a cerebral primitive neuroectodermal tumor has been reported previously. In the present case, we will present some unusual previously unreported membranous structures and alterations in the cytoplasm and nucleus of the tumor cells.Specimens were cut into small pieces about 1 mm3 and immediately fixed in 4% glutaraldehyde in phosphate buffer for two hours, then post-fixed in 1% buffered osmium tetroxide for one hour. After dehydration, tissues were embedded in Epon 812. Thin sections were stained with uranyl acetate and lead citrate.In the cytoplasm of the tumor cells, we found paired cisternae (Fig. 1) and annulate lamellae (Fig. 2) noting that the annulate lamellae were sometimes associated with the outer nuclear envelope (Fig. 3). These membranous structures have been reported in other tumor cells. In our case, mitochondrial to nuclear envelope fusions were often noted (Fig. 4). Although this phenomenon was reported in an oncocytoma, their frequency in the present study is quite striking.

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