Cross-linking and silanization of clay-based multilayer films for improved corrosion protection of steel

Calcium ions in the concentration range 5-100 mM inhibit auxin-induced cell elongation and wall extensibility of plant stems. Inhibition of wall extensibility requires that the tissue be living; growth inhibition cannot be explained on the basis of cross-linking of carboxyl groups of cell wall uronides by calcium ions. In this study, ultrastructural evidence was sought for an interaction of calcium ions with some component other than the wall at the cell surface of soybean (Glycine max (L.) Merr.) hypocotyls.

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Embedding Procedure for Water Swollen Samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006951x ◽

1970 ◽

Vol 28 ◽

pp. 504-505

Author(s):

Ann M. Thomas ◽

Virginia Shemeley

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Ion Exchange ◽

Structural Changes ◽

Cross Linking ◽

Ion Exchange Resins ◽

Transmission Electron ◽

First Pass ◽

Exchange Resins

Those samples which swell rapidly when exposed to water are, at best, difficult to section for transmission electron microscopy. Some materials literally burst out of the embedding block with the first pass by the knife, and even the most rapid cutting cycle produces sections of limited value. Many ion exchange resins swell in water; some undergo irreversible structural changes when dried. We developed our embedding procedure to handle this type of sample, but it should be applicable to many materials that present similar sectioning difficulties.The purpose of our embedding procedure is to build up a cross-linking network throughout the sample, while it is in a water swollen state. Our procedure was suggested to us by the work of Rosenberg, where he mentioned the formation of a tridimensional structure by the polymerization of the GMA biproduct, triglycol dimethacrylate.

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The Current Situation in Chemical Stabilization of Biological Materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100093912 ◽

1972 ◽

Vol 30 ◽

pp. 132-133

Author(s):

John H. Luft

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Osmium Tetroxide ◽

Molecular Level ◽

Cross Linking ◽

Chemical Stabilization ◽

Specimen Preparation ◽

Sufficient Condition ◽

Radio Telescopes

With information processing devices such as radio telescopes, microscopes or hi-fi systems, the quality of the output often is limited by distortion or noise introduced at the input stage of the device. This analogy can be extended usefully to specimen preparation for the electron microscope; fixation, which initiates the processing sequence, is the single most important step and, unfortunately, is the least well understood. Although there is an abundance of fixation mixtures recommended in the light microscopy literature, osmium tetroxide and glutaraldehyde are favored for electron microscopy. These fixatives react vigorously with proteins at the molecular level. There is clear evidence for the cross-linking of proteins both by osmium tetroxide and glutaraldehyde and cross-linking may be a necessary if not sufficient condition to define fixatives as a class.

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Parathyroid gland before and after cisplatin treatment

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128584 ◽

1987 ◽

Vol 45 ◽

pp. 860-861

Author(s):

S.K. Aggarwal ◽

J.M. Fadool

Keyword(s):

Parathyroid Gland ◽

Wistar Rats ◽

Antitumor Agent ◽

The Body ◽

Cross Linking ◽

Limiting Factor ◽

Hormonal Changes ◽

Primary Mechanism ◽

Before And After ◽

Dna Strands

Cisplatin (CDDP) a potent antitumor agent suffers from severe toxic side effects with nephrotoxicity being the major dose-limiting factor, The primary mechanism of its action has been proposed to be through its cross-linking DNA strands. It has also been shown to inactivate various transport enzymes and induce hypocalcemia and hypomagnesemia that may be the underlying cause for some of its toxicities. The present is an effort to study its influence on the parathyroid gland for any hormonal changes that control calcium levels in the body.Male Swiss Wistar rats (Crl: (WI) BR) weighing 200-300 g and of 60 days in age were injected (ip) with cisplatin (7mg/kg in normal saline). The controls received saline injections only. The animals were injected (iv) with calcium (0.5 ml of 10% calcium gluconate/day) and were killed by decapitation on day 1 through 5. Trunk blood was collected in heparinized tubes.

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